Well, that went well, not!

[neksmerj]

I'm finally back into restoring my Hercus, and am concentrating on the bed, feet first.

I thought I'd try electrolysis. I found a suitable plastic tub that when filled, would cover both feet.

In the bottom of the tub, I placed a sheet metal plate for the feet to sit on. Around the four walls I placed four more sheet metal plates, all electrically connected.

The electrolyte was water with a handfull of bi-carb soda. The power supply was an Arlec battery charger.

Satisfied all was well, I switched the charger on. The current meter went hard over full immediately, raising a few doubts. Switching off, I rechecked nothing was touching that shouldn't.

Switching back on, we had bubbles, wallah. That lasted about one minute and the Arlec shut down.

As a substitute I had a 24V dc power supply, so hooked that up. That lasted 3 minutes and blew a fuse.

Have I got too many electrode plates? Any other ideas?

Ken

[morrisman]

hi Ken

you need to move the plates away from the lathe bed ..more distance = less current flowing . You might have to find a larger container , the container MUST be non-conductive eg plastic

BTW I use this method to remove rust and paint with caustic soda :2tsup: I have found that the laundry powder from the Warehouse works great as well .

I use a cheap K mart charger that must be 30 years old..you only need around 2-3 Amps .

Mike

[malb]

If the water is fairly shallow to proccess the feet, and you tossed in a handfull of bicarb, the solution may be too strong, allowing excess current. My understanding is that the solution is generally fairly weak, with just enough concentration to allow limited current flow. There is nothing in the system to limit current flow other than electrolyte concentration, overdo the concentration and the solution is a short circuit.

Two suggestions;

1. Make a new solution with a similar amount of water and about a teaspoon of bicarb. Check the current flow and add very small amounts of bicarb til you get the current into the 2A range.

2. Use the existing solutuin and 12V source, but connect with 1 or 2 12V brake lights (parallelled) in series with the bath to limit current to the 2 A range.

[kwijibo99]

Hi Ken,
When you say "In the bottom of the tub, I placed a sheet metal plate for the feet to sit on. Around the four walls I placed four more sheet metal plates, all electrically connected"
Does that mean you had the plate the feet were on connected to your sacrificial anode?
If so then I suspect that's the source of your problem.
Assuming the feet are rusty they will have high resistance to start with but this will drop rapidly as the electolsys progresses.
Put an insulator between the bottom plate and your feet or suspend them with string or wire above it and all should be ok.
When using electrolsys the larger the surface area of what is being cleaned and the anodes the higher the current will be, the strength of the electrolyte usually doesnt matter that much.

If I have misunderstood, my appologies and the best thing would be to reduce the size of your anodes or as Mike said increase the distance between them.
Sheet metal anodes probably wont last long, I use rail bed plates, the things that go betwen railway line and the sleeper, you can usually find some lying along the train lines. Watch out for the big rolling things though.:o
Some people use stainless for the anode but this results in cromium in your used electrolyte which is not a good thing.
Cheers,
Greg.

[neksmerj]

Off to the supermarket to buy some washing soda. In my first attempt at electrolysis, I used bi-carb soda (baking soda). Maybe that's why everything went pear shaped.

The Arlec battery charger is ok, must have tripped out on thermal overload. My 24v dc power supply blew a fuse, that was a quick fix.

I'll try electrolysis again tomorrow using the Arlec switched to low, and ditch the metal plate in the bottom of the tub. Instead I'll connect each foot with a cable directly, and do one at a time.

Negative lead to the work, and positive leads to the electrodes hooked up in series.

Wish me luck.

Ken

[BobL]

Whether it's baking, washing or bicarb soda you need a lot less than you think.

I start off with nothing except water and then slowly add small amounts of concentrated soda solution (mixing it in thoroughly) until the current is around 4 A.

[neksmerj]

Thanks BobL.

I'll give your method a go, the Arlec battery charger has a voltage & current meter on it, so should be a snap.

Watch for the smoke in my area.

Ken

[steran50]

HI:),
Might be to many Electrode Plates as You said. I remember when I used the procedure I had only one Anode and that was a piece of 50mm x 8mm Stainless Flat bar about 350mm long (the anode stood upright in the Container). I have tried it with both Washing Soda and Bi-Carb Soda, I actually seemed to get better results with the Bi-Carb.

[JohnQ]

Ken
Have look at this thread started by BobL april 2011.

http://www.woodworkforums.com/f65/electrolysis-using-old-computer-power-supply-134107/index3.html

Post 45 by Ropetangler suggests the use of stainless steel anodes produce "hexavalent chromium".
Remember the movie "Erin Brockovich"

I've used 2 strips of old lead sheet as anodes in a bucket & washing soda, works well. Try this site aswell =

Rust removal by electrolysis (http://antique-engines.com/electrol.asp#wash-soda)
This site warns about the use of SS aswell.

Regards
JohnQ

[neksmerj]

I'm now using only two ms electrodes, each about 100mm x 100mm, and am attempting to clean both lathe bed feet at the one time.

Initially the current draw was zero until I gradually added some dissolved washing soda (Lectric soda crystals). Steadily the current rose and is now sitting on roughly 3 amps.

Q1. Can I expect this process to remove the paint along with the rust?

Q2. How long will this process take, hours, days, weeks?

I'm getting all the froth and bubbles, so things are cooking.

Had to put a cloth over the tub to stop puss from drinking out of the tub. Didn't know cats like water, mine does.

I'll keep updating as things progress.

There's a couple of snaps just to keep AB from winging that I don't do anything on my Hercus restoration.

Ken

[BobL]

I'm now using only two ms electrodes, each about 100mm x 100mm, and am attempting to clean both lathe bed feet at the one time.

Initially the current draw was zero until I gradually added some dissolved washing soda (Lectric soda crystals). Steadily the current rose and is now sitting on roughly 3 amps.

Q1. Can I expect this process to remove the paint along with the rust?

Q2. How long will this process take, hours, days, weeks?

I'm getting all the froth and bubbles, so things are cooking.

Had to put a cloth over the tub to stop puss from drinking out of the tub. Didn't know cats like water, mine does.

I'll keep updating as things progress.

There's a couple of snaps just to keep AB from winging that I don't do anything on my Hercus restoration.

Ken

If you start with clean surfaces, ie remove all oil and grease and if the rust is only surface rust, using 3 A you should get pretty well all the rust converted to FeO with 24 hours. If you want to be sure you can got to 48 hours. For thick ie mm scale, it can take 3-4 days at 3A - maybe up the A for this level of thickness.

I would be very wary about putting any sort of cover on the container as that may trap some hydrogen and oxygen.
Bubbles should be minimized as they will also trap some hydrogen and oxygen.
A while back I posted about a small [non-lethal] explosion that a poster in Home shop machinist experienced with too many bubbles and a short.
Make sure you disconnect all power etc before moving/removal of objects being treated.
For the information of others, Battery/crocodile clips can easily slip off and make sparks - connect my wires firmly with nuts and bolts so connections can't just slip off (just like you did).

Once it is done have your next treatment phase ready because the raw metal will start re-rusting in minutes.
Boiling in pure distilled water is a a good treatment - water must be ready and boiling furiously when object is put in.

Will it take the paint of , it might - depends on the type of paint and length of time used.

[morrisman]

If you want to strip the paint off, and remove the rust , use Caustic Soda as the electrolyte . But don't get it on exposed skin, it burns .

It also helps to use hot water to begin with, this speeds up any chemical reactions .

Mike

[waxen]

Hi, Just a note about using this process. Hydrogen embrittlement is a side effect that increases with time spent in the process. I've had good items break in my hands from leaving them in for too long.
The solution is to bake the parts in an oven for a few hours after the process.
I don't pretend to know all the science involved but there is plenty of info on the web.

[neksmerj]

At the risk of boring everyone sh*tless, a quick update.

I did not leave the process running overnight, in case something went wrong. So far, no smoke. Power is back on now.

The paint is lifting off, and in light of what Morrisman suggested, could the stripping process be speeded up by also throwing in some caustic soda into the mix.

I ask not knowing if mixing the two chemicals together could be dangerous. ie washing soda and caustic soda together.

If I risk blowing up half the neighbourhood, maybe I should tip out the electrolyte and start again.

So far so good.

Ken

[GSRocket]

I sometimes wondered what the difference was, so I had a bit of a search...and I think it wouldn't matter.

"The difference between baking soda and washing soda is water and carbon dioxide.
Baking soda’s chemical makeup is NaHCO3 (1 sodium, 1 hydrogen, one carbon, and 3 oxygen molecules).
Washing soda’s chemical makeup is Na2CO3 (2 sodium, 1 carbon, and 3 oxygen molecules).
When baking soda is heated up to high temperatures, it breaks down to become washing soda, water steam, and carbon dioxide."

[neksmerj]

Thanks GSRocket for your description of washing soda & baking soda, but my question is whether it's safe to mix washing soda & caustic soda together with water as an electrolyte.

Ken

[morrisman]

Ken

Not being a chemist, I cannot answer your question. But there isn't any reason to mix them together , using caustic alone will remove both paint and rust. So why would you mix the washing soda in ?

The rust will turn black, you can then brush it off with a wire brush .

I have read about the embrittlement thing, but it has never happened to me .

Mike

[neksmerj]

Hi Morrisman,

I'm not a chemist's bootlace either, so it sounds that caustic soda can be used alone. I presume that what ever chemical is added to the water, it acts as an agent to aid in the conductivity of electricity. I plead dumb your honour, someone will have the answer.

Ken

[neksmerj]

Took the plunge and tipped in some caustic soda with immediate results.

The amp meter jumped from 3 amps to off the scale, and shut down. The Arlec is dual voltage, 6 and 12 volts, so switched it onto 6 volts and tried again.

Things are bubbling away again on 6v with a current draw of 4 amps.

The lathe bed feet were originally Hercus green, and have been over painted in sky blue by students. Reckon they applied the paint with a mop.

The blue has all come off in sheets, and now the green is loosening.

Ken

[morrisman]

link

ELECTROLYTIC RUST REMOVAL (ELECTROLYSIS) (http://myweb.tiscali.co.uk/andyspatch/rust.htm)

[neksmerj]

The electrolytic process finally took 99% of the paint off including the factory paint underneath. I'm surprised that the inside of the castings were not given a lick of undercoat.

In fact, there was no sign of undercoat on any of the castings.

A final lick with a wire brush in the angle grinder, and the feet are as good as new cast.

There's a tiny bit of rust on the inside, but some undercoat will fix that.

I might try and get some undercoat on today, if the wind drops.

Sorry about the crappy snaps, iPhone cameras are next to useless, so is the photographer.

Ken

[simonl]

Wow. They came up neat. I may have to consider electrolysis next time i need to get some crap off any castings. What did you end up using? A caustic soda/washing soda combo? 50:50 mix?

Simon

[Ueee]

They look real good:2tsup:, as you say like new castings.

One question though, will the electrolysis remove oil/grease as well, or just rust and paint?

[neksmerj]

I'm not sure if electrolysis will remove grease, but I'd reckon with a 50/50 mix of washing soda and caustic soda, nothing would survive.

Still, I would chuck the part in a tub of kero, and hit it with a brush. I think the cleaner the part, the faster the process will be.

Now got some etch primer on. I'm using White Knight Rust Guard S.L.S. Etch primer, grey. A bit over $10 at Bunnings.

More shock, horror, gasp. My tin of Dulux enamel top coat has gone hard, and to make matters worse, the sticker on the can with the Hercus green formula on it, has totally faded, unreadable, zilch, jack sh*t..

Guess I'll have to take a painted part in to the paint supplier and have it colour matched.

Question. Will any paint mob custom mix a colour and put it in a spray can?

Ken

[kwijibo99]

Hi Ken,
All depends on how fussy you are going to be about the colour match but Killrust Wilderness (a Colourbond colour) is a pretty close match to the Hercus green.
Give any of the Dulux spray paint you get from the green shed a big miss, its fast drying but chips if you look at it mean and disolves with the breifest exposure to petrol etc.
Killrust takes a while to dry but it gives a very durable finish and I think the white Knight metal paint is pretty good too.
Killrust is cheaper at the big blue shed than White Knight at the big green shed.
Cheers,
Greg.

[Steamwhisperer]

The electrolytic process finally took 99% of the paint off including the factory paint underneath. I'm surprised that the inside of the castings were not given a lick of undercoat.

In fact, there was no sign of undercoat on any of the castings.

A final lick with a wire brush in the angle grinder, and the feet are as good as new cast.

There's a tiny bit of rust on the inside, but some undercoat will fix that.

I might try and get some undercoat on today, if the wind drops.

Sorry about the crappy snaps, iPhone cameras are next to useless, so is the photographer.

Ken

HI Ken,
reckon I'm going to have to try that method. I have always used molasses and water, smells nice but messy.
Is your Iphone in a cover as I found the flash is distorted with the cover on. I now slide the lens and flash just clear and take the shots.

Phil

[Michael G]

I find a 50:50 mix of turps and meths is very good for stripping paint.

Michael

[neksmerj]

Struth, I can't take a trick. I went to Bunnings to buy a new tin of Dulux Quit Rust epoxy enamel, Green Freeze, and guess what, they no longer stock it. It was the closest colour I could find to match the Hercus green.

They directed me to a nearby Dulux Trade Centre, and got the same story, "sorry, it's been discontinued". Bugger me.

At best, if I take a painted sample in, they will try and match it in an industrial paint. Won't be quit rust, & won't be epoxy based.

This will teach me for being slack in the restoration process.

Ken

[Michael G]

Go for the Wattyl Kilrust. I have it on all my machines that have needed painting and works a treat

Michael

[neksmerj]

Gentlemen, thanks for all the comments re Hercus green paint. I want to stick to the paint I started with, but it looks like I have to use a normal Dulux enamel or industrial enamel.

I sent am email to Dulux expressing my desire to continue with the Quit Rust Epoxy enamel, but have been informed that this type of paint was discontinued in 2009.

Is colour matching done by eye, or do paint centres have a computer matching system?

I still have 1/3 of a litre of the original paint left, but it's covered with a thick skin. Can I recover this paint, and how? I will be applying the paint with an air brush.

Ken

[Oldneweng]

Gentlemen, thanks for all the comments re Hercus green paint. I want to stick to the paint I started with, but it looks like I have to use a normal Dulux enamel or industrial enamel.

I sent am email to Dulux expressing my desire to continue with the Quit Rust Epoxy enamel, but have been informed that this type of paint was discontinued in 2009.

Is colour matching done by eye, or do paint centres have a computer matching system?

I still have 1/3 of a litre of the original paint left, but it's covered with a thick skin. Can I recover this paint, and how? I will be applying the paint with an air brush.

Ken

I have recovered paint found in this condition a number of times by removing the skin and giving the remainder of the paint a good stir. Run a blade around the edge and lift the skin out. It may be a bit thicker than it used to be and I would not rely on it being an exact colour match. What has evapourated would be solvent which can be replaced. I am also a fan of Kill Rust myself. Just because I have had success in the past and it is readily available.

Regarding the White Knight range of paints, I hope the formula has improved since I used it to paint a motorbike for my stepson about 20 yrs ago. The paint just ran off as soon as petrol touched it.

Dean

[neksmerj]

Moving along, I'm onto stripping the Hercus lathe bed. Using a wire brush in an angle grinder, is a pain in the *rse.

Vibrations from the out of balance wire wheel, make your hands numb, and the flying wires make your pants look like a porcupine, not to mention the dust.

I've decided to use the electrolysis process. With this in mind, I knocked up a 3D drawing of a trough in 25mm MDF, and showed it to a cabinet maker.

$180! I think not, that sort of outlay is too much for something I'll use once.

Let's get creative. How can I construct a cheap and cheerful dam to hold the lathe bed. I've had a couple of ideas. Dig a trench in the back yard and line it with polythene, or

construct some dam walls around the bed with bricks, and line that. Your ideas are welcome.

Ken

[pipeclay]

Why not use a plastic barrel cut in half,might not get the whole lot at once,but possibly cut and join with salastic or similar.

[Stustoys]

While I dislike the brick idea and like the trench idea. How about an old bath?(I assume the boss would be a little unset if you used the one in bathroom ;)

Stuart

p.s. How about standing it up in 44 gallon drum? piece of wood on the bootom and some rope at the top to keep it standing up straight?

[Ueee]

Kiddies wading pool? I think the trench and tarp idea is good, even just a few boards in a box shape lined with a tarp.

[Anorak Bob]

Hey Ken,

If you do manage to exit this morass with a bed suitable for repainting, then I might have come up with an attainable over the counter colour match ( well if not an exact match, close). I brought home an RAL fan deck thinking Reseda Green 6011 would be something like the original green on our lathes. Too bright and clean looking. Then I compared the colours on a Taubman chart. Wilderness, a Colorbond finish looks good. Taubmans and White Knight are manufactured by PPG Architectural Coatings so I imagine it shouldn't be difficult to have their Rust Guard Epoxy Enamel tinted to match.

And I asked one of the interior designers at work about the Dulux Green Freeze. She reckoned she could find no reference to that colour.

BT

[Greg Q]

Ken, just use your rubbish bin for electrolysis. Its the perfect size and its free. The last big job I did used a few chunks of rebar wired together for the electrodes.

Greg

[morrisman]

Ken, just use your rubbish bin for electrolysis. Its the perfect size and its free. The last big job I did used a few chunks of rebar wired together for the electrodes.

Greg

+1 on the rubbish bin. I used one to clean out a engine block in caustic soda and hot water

[neksmerj]

A few good ideas there. Not sure about using a bath or wheelie bin due to the volume of water and amount electrolyte that would be needed, and with the wheelie bin, only half the bed could be done at a time. Man handling the lathe bed by myself, would be beyond me.

I have an outside sturdy timber table that I'll attach some boards to, then line with polythene.

I don't know the chemistry behind electrolysis, so ask, do the positive electrodes need to be steel? Could aluminium foil be used as a substitute?

Ken

[Ueee]

Hi ken,
I think you would end up dissolving the ally pretty quick, and it may even coat the steel depending on polarity. Remember electrolysis can be use to brass/tin/copper/gold/silver (as well as many more probably) plate items. Electroplating is really just electrolysis in reverse.....

[simonl]

242049This 10,000L portable collar tank may be a little on the large side but think of all the other stuff you could do at the same time! :;

Simon

[neksmerj]

Buried under a pile of partly dismantled push bikes, in a corner of the garage, was a book case unit, perfect. I honestly didn't know it was there.

After a quick trip to the hardware shop, I returned with a piece of polythene sheet, some kero and a brush. Thought it would be best to get rid of as much gunk and shavings as possible.

It didn't take long to wire every thing up, get the box level, and fill with water. Hooked up to the Arlec, no current flowed as expected.

The next step was to mix some washing soda and caustic soda into a solution with hot water, and add it to the mix. Immediately, the amp meter climbed up to 4 amps on 6 volts.

Edit: Had to add more fresh water and remove one of the electrodes to prevent the Arlec charger from tripping out. Maybe it's the hot weather.
Edit2: Put the 4th electrode back in, The Arlec is tripping out every 30 seconds or so, but then switches itself back on. Has to be the 30 degree heat, this thing should be good for 6 amps at least.

Here's a few more pics.

[Ueee]

Nice one!
I'm very interested in this as i don't really want to strip another machine with a wire brush and grinder like i did with the shaper. Although making a trough to fit the 8' long leblond bed would be ridiculous, i would like to do the rest of the machine and even maybe make a very shallow tray to put the bed in just to do one side at a time.

Does anyone know if cleaning a part with a bronze bush or brazing on it would be ok?

[Stustoys]

Guess what the "4" in "Charger 4" means? ;)
And yeah the heat will knock it about.

Am I seeing things or are things starting to happen in the fourth picture?

Stuart

[neksmerj]

Hi Stupots,

Please explain! You have lost me.

Are you referring to the nude sheila in the background, or the cat drinking out of the trough?

Ken

[Stustoys]

Hi Ken,
Charger 4 = 4 amp battery charger
I believe the overload is a bimetallic strip on the secondary.
Any increase in ambient temp will decrease the current it will carry before tripping.

Stuart

p.s. Or are you talking aboutht e fourth picture? is that rusting water I see?

[Ueee]

All this talk of clean parts has got me excited, and i got SWMBO to get me some washing soda on her way home today. I stuck one of the Leblonds cast iron guards in a ice cream tub, oil, grease and all, with a single anode and hooked up my charger. I added soda till i had only 200mA, i wanted to start slow as there is also a brazed repair on the guard.
Very quickly some murky black stuff started to gather around the anode, i guess this is the oil and scum. I only let it run for 30 min or so, i will give it some more tomorrow.

[neksmerj]

If you enjoy watching grass grow, then you'll love watching the electrolysis process in action, it's very slow.

I reckon it's going to take a few more days, we'll soon see.

Things are certainly happening, lots of bubbles, scum and strips of loose paint afloat.

A few more snaps

Ken

[Ueee]

Mmmmm, soupy......

I seem to have a lot more orange froth on the top of mine than you Ken, but no orange rust was on the part:?. After 7 hours at 1A the anodes are covered in orange rust though. The grease and oil has mostly come off, just a few spots where it is thicker to go. As for the brazing, it has gone black but doesn't seem to be being eaten and a quick hit with a wire brush cleans the black off and reveals clean bright bronze. I just threw a really gunky bolt in and will leave it overnight to see how it goes.

[neksmerj]

Ueeeeeeeeee,

What did you use as an electrolyte, and what are you using to power up the system? 6V or 12v charger?

I've had to reduce my voltage to 6v in an effort to stop the Arlec tripping out. On 12v, the current draw is about 6A, way too much.

Ken

[Ueee]

Hi Ken,
Just washing soda at this stage, i have to get some caustic to try. I am using a 12v charger. I hooked it up with no soda then added soda till i have about 1A. My charger is only a cheapy and is rated to 2A. I should duck out and check the bolt.....

[Ueee]

Here is a pic of the orange scum and one of the bolts after about 2 hours in the tub next to another uncleaned one. They are 2 of the bolts that hold the Leblonds head on, they are 5/8 i think. Hmmm.....orange scum pic seems to be corrupt....i'll try again tomorrow.

242317

[neksmerj]

Today I decided to take the bed out of the electrolyte, for a squize. It's been in there for a few days, and looks as though it could have done with several more days.

80% of the outside paint had dissolved leaving the red paint inside the bed, almost untouched.

Rather than struggle to put the bed back in the bath, I decided to attack it with a wire brush in the angle grinder. A lot of the outside paint almost blew off, so it was an easy job.

My big problem now is how to suspend the bed so I can get some under coat on after masking. I intend undercoating all of the bed, inside and out, apply several layers of top coat, then redo the red paint inside with a brush.

A few more crook pics.

[neksmerj]

I finished the day getting a couple of layers of undercoat on, so it's time for a glass of medicine.

For the top coats, I'll have to think up a way of cradling the bed so I can rotate it. Any ideas?


Another lousy picture, bloody ipod cameras, no control over settings.

Ken

[Ueee]

Hi Ken,
Its a shame it didn't get more off. I think you would have needed to drop a couple of anodes in between the ways to get the inside stripped. I think i may know the other problem. I *think* the best thing to have is a much stronger solution of electrolyte and to control the current electrically. The site Mike linked to earlier in the thread states a 10-1 ratio of water to soda by weight.
I have now ditched the battery charger and gone to a 5A switchmode driver. It seems to be limited to about 6A, i added a bit more soda (maybe 200g in my 50l) and have a current up at about 5.8A.......things are cookin!

As for the painting, why not hang the bed from the webbing which will be red?

[neksmerj]

Hi Ueee,

That certainly looks like it's cooking away nicely. I reckon you're right about the red paint inside the bed. Maybe a couple of strategically placed electrodes inside the bed, would have achieved better results. You are right about suspending the bed from the central ribs. That's about the only place that won't get the green top coat.

Glad I'm not doing this for a living, it's a pr*ck of a job.

Good luck with your restoration project.

Ken

[Stustoys]

Whats it weigh?
How about a tripod and hang it vertically?

[neksmerj]

Hi Stu.

To be honest, I don't know. I can just lift it so I'm guessing 50KG. Perhaps Pipeclay will know.

Ken

[Stustoys]

A kids swing would hold 50kgs.
Not sure I'd be game to use the hills hoist while it would likely hold it, the price for failure is a little high.:rolleyes:
If you have 3off 8" lenghts of 2 by 4, a lashed up tripod should do.
A plank between to ladders?
Anything that will hold you up will hold it up.
Vertical will be a little harder to spray the outside but it should be easier to set up and easier to spray the inside.

Stuart

[neksmerj]

I have a huge tum tree in my back yard, with a branch hanging over the outside area where I work. I just don't know if it will support the weight of the bed.

Suppose I could throw a rope up and over it, and hang off it to find out.

The things we do in the nature of engineering.

Ken

[Ropetangler]

Hi there boys, I used an Arlec Charger4 as my P/S to clean up an old very rusty Leblond lathe bed about the same size as the one you are doing Ken, and I used an old headlight (from a car) as a current limiting resistor, to stop the bi-metal cutout operating. Here in Tasmania, I found that an indicated 4A would generally work continuously, but any higher and the P/S would cycle on and off, - slowly if you were ony marginally over the 4A, but quickly off and slow to recover if you had pinned the needle on the Ammeter. If you can lay your hands on some Graphite sheet, you will have great anode material as the carbon doesn't corrode, nor does it pass into solution, only to plate out on the item being de-rusted, like metallic anodes will. The only stuff I have seen on eBay was from overseas though, so unfortunately I have been unable to locate any locally. If anyone comes up with a local graphite supply, I will put my hand up for a couple of square feet if there is enough to go round, as always depending on price. Before I became aware of the potential for creating toxic chrome compounds, I used a stainless feed trough I made years ago when I had access to scrap stainless from the worn skins of the drums in a magnetic separation process line in an iron ore mine I worked at. I made the stainless trough the anode and had the lathe bed sitting on some polly pipe to insulate it from the trough. I had to do it in 2 goes, as my trough wasn't deep enough to fully submerge the LeBlond bed, so after a day or two, I rotated the bed 180 degrees, and gave it another day or so. It worked really well, stripped all the paint, even the stuff from the webbed section between the ways, and turned the bed from a heavily rusted item to one which looked nearly brand new. I did lightly go over the ways with a green kitchen Scotch pad. and used a pressure spray to remove any stubborn spots of paint, thinking back on that it may just have been the garden hose with a nozzle, if so then it would have been about 45psi maximum, but it blew all the last bits off.
That system worked well, better than I have been able to replicate using scrap iron bits as anode material, and perhaps because the anode fully surrounded the lathe bed, the action as quite even, much better result than I get using scrap iron junk as anodes. I asked questions of the local uni campus chemistry section, on how the hexavalent Chrome compounds might be prevented from forming, but could get no definite answer on whether it was possible to control the formation of these toxic compounds, by control of temperature, current density, temperature or any other variable. In the end I decided that I should play safe, and didn't make use of the trough as the anode, in spite of its obvious benefits
I too started by using caustic soda, and then went to washing soda, but no matter what you use, you need so little to make it work, I doubt that it would likely become a problem to dispose of, or to handle if you use caustic soda as your electrolyte. Just remember to use eye protection, especially if mixing up using hot water, in fact I would recommend using cold water for solution preparation using chemicals such as these, they will still get hot, as the material dissolves. Safety shields or goggles are only optional if you wont find blindness a problem in your life.
A suggestion for the tank might be a sheet of form ply used to build a box of suitable size, then varnished and finally fitted with some plastic sheet like forticon. Use sort stubs of poly pipe to lift the item above the base of the box and to prevent damage to the varnished plywood box. I hope that this gives some encouragement to you de-rusting people, but I found that it worked well for me. Cheers,
Rob

[jhovel]

A couple of years ago I electrolytically de-rusted a vintage motocycle exhaust system. The carbon deposits on the inside of the mufflers made that hard going. So I tried hot caustic soda and large electrodes. I connected my car battery to it with the car engine running. The mufflers were clean as a whistle inside and out in about 30 minutes and the car battery was flat. I estimate the current to have been around 70A or more. The jumper leads I used were too hot to touch and the car alternator was audibly working hard. The battery still went too flat to start the car again after the 30 minutes....
The steel mufflers came to no harm at all in the process. :U

[neksmerj]

Thanks RT for your experience.

This might encourage others to have a go at the electrolysis process, it does work!

Especially for smaller parts.

Ken

[Ueee]

With the graphite would the size rules still apply? (ie same surface area as part to be stripped)

STIRRING ROD GRAPHITE 16mm - FOR MIXING METAL WHILE MELTING | eBay (http://www.ebay.com.au/itm/STIRRING-ROD-GRAPHITE-16mm-FOR-MIXING-METAL-WHILE-MELTING-/330741931568?pt=AU_Business_Industrial_Mining_Equipment&hash=item4d01c15e30)

Graphite rod, in Aus too....

What about graphite slip cloth, the stuff you put on belt sander platens?

[Stustoys]

Hi Ken,
Sounds like it might do the job. Maybe a couple of props if it looks a little "iffy"

Hi Rob,
Would this suit?
Graphite Slip Cloth | The Sandpaper Man (http://www.thesandpaperman.com.au/graphite-slip-cloth/)
I have some I can soak in little in water to see what happens if you'd like.

Stuart

[Ropetangler]

Hi again everyone,
Ewan I think that the rods would only work well for similar shaped items you were trying to clean up, but the graphite slip cloth that Stuart has volunteered to try out sounds well worth the time and effort to try. Try it in a working solution Stuart, just to be sure that the fabric backing that I presume that the slip cloth has, is not compromised by being wet in a strong alkaline solution. If it does work, it could be reasonably economical to use, and also convenient as it could be curved around the inside of the tank to fully surround the cathode which would help ensure an evenly cleaned surface. I would think that it is definitely worth trying for this purpose, and look forward to hearing the result.

Hi Joe, your solution must have just about boiled with the current going through that lot, Glad to hear it worked well though, - tell me was the exhaust system chrome plated ( or perhaps in those days nickel plated, or was it just black tube as a matter of interest? Regards to all,
Rob.

[Michael G]

Graphite is used for making electrodes for EDM machines these days so if you can find a toolmaking concern they may be able to point you in the right direction.

Michael

[Stustoys]

Reading through the thread again I found caustic, baking, bi-carb and washing sodas.
Does anyone have a favorite for the test?
Dishwasher powder is caustic isnt it? Woud that do?

-work, +graphite right?

Any current density you'd like me to aim for?

Stuart

p.s. Maybe I should see if I can get this stuff to conduct first. yeah should it should but does it?

[kwijibo99]

G'day All,
Just a couple of comments regarding paint, oil & grease and the electrolsys process.
If what you are trying to clean using electrolsys has any oil or grease on it the whole process will be severely inhibited.
For electrolsys to work the electrolyte, which is essentially water, needs to be in contact with what you are trying to de-rust, any oil on the surface will reduce or even prevent this contact from occuring. Give what you intend to clean a spray with the hose and look for places where the water doesn't stick, these will not de-rust properly.
If you use washing soda to make your electrolye then you get a bit of degreasing action but it's not much and you will still get uneven de-rusting.
If you use caustic soda to make your electrolye then you get a bit more of degreasing action but you will still get uneven de-rusting.
Either way your electrolyte won't last as long (assuming you want to use it more than once)
You will get much better results if you degrease what you want to de-rust before you put it in your electrolsys tank.
If what you are de-rusting is not oily but painted thats not really a problem because the painted bits generally wont be as rusty and the electrolsys process will remove the paint but it takes a while and sludges up your electrolyte.
I have always had good results on old parts with the following process, lets assume the part is greasy and still has some old paint:

Step 1: Trip to the local car wash and give your part a good pressure wash. (you might get some funny looks though)
Step 2: Place your part in a caustic bath. If using a bucket I use about a laundry scoop of caustic, if if its a big bit I use the wheelie bin and the same ratio of caustic that way it gets a clean too. If it's too big for the wheelie bin then it's off to the sand-blaster:U. VERY IMPORTANT: put the caustic in first then add a kettle of boiling water SLOWLY at first, don't do this in your shed or you will find yourself doing a lot more de-rusting in the future. Wear a face shield, this stuff will burn you if it gets on your skin when its concentrated. I usually have a bottle of vinegar handy too because water won't help and can spread the burn. Fill the rest with cold water and don't forget to allow for the volume of your part so it doesnt overflow when you add it. The solution is less dangerous now but dont get it on yourself if you can avoid it and wash it off straight away if it does, you may not feel the burn straight away but it will still burn you. Put in your part and let it soak for a few hours or a day or even two days, depending on how thick the paint and oil is.
Step 4: When your bit is clean pull it out of the caustic, it should have a nice even coat of brown rust but no oil or paint. Give it a good hose and any remaining paint will usually wash off and even the brown rust will wash away.
Step 5: Fill a bucket with water and add a cup of vinegar (same ratio if you used a wheelie bin) and let your part soak over night. This step is particularly important if your part is cast iron and you intend to paint it. CI is like a sponge and will soak up the caustic which will cause your paint to bubble sooner or later if it's not neutralised.
Step 6: Remove your part and give it another hose. Dump the vinegar solution into the caustic solution (carefully) and they will neutralise each other before disposing of the liquid down the sewer, not the storm water, collect all the sludge in the bottom then bag it up and bin it. (Gotta be environmentally friendly ya know)
Step 7: Now go ahead with the electrolsys process. I only ever use bi-carb for the electrolyte and steel for the anode, it's cheap and plentiful. It doesnt matter how rusy the electrolyte gets you can use it over and over, I just top it up with water when it gets a bit low. After a while I just tip it out on the lawn which loves it and make up a new batch.
You should only need to run at a few amps and your part will be prefectly clean within a couple of hours.
Step 8: let it dry and if painting the part prime it right away, if not then give it a good rub with boiled linseed oil or steam cylinder oil if you can get any (Phil?) these are about the best things I've found for protecting raw iron.

If I'm not in a hurry I actually prefer to use molasis rather than electrolsys, it's just a personal thing it think but you just dump it in and forget about it for a month or so then pull it out and like magic it's clean.

Sorry about the long winded post, I just though it might be of some help.
Cheers,
Greg.

I

[Ueee]

Hi Stuart,
I don't think it matters all that much on what you use for the electrolyte, the main thing is that the cloth is conductive and doesn't just fall apart. - to work + to graphite is right. Aim for the highest amps you can, that should put it through the most electrical stress.

[neksmerj]

I undercoated my Hercus lathe bed, inside and out, before getting to get a colour chart to match the red inside the casting.

BT, if you are listening, can you tell me a close colour, I know you have Dulux colour swatches at work.

Ken

[Ropetangler]

Step 2: Place your part in a caustic bath. If using a bucket I use about a laundry scoop of caustic, if if its a big bit I use the wheelie bin and the same ratio of caustic that way it gets a clean too. If it's too big for the wheelie bin then it's off to the sand-blaster:U. VERY IMPORTANT: put the caustic in first then add a kettle of boiling water SLOWLY at first, don't do this in your shed or you will find yourself doing a lot more de-rusting in the future. Wear a face shield, this stuff will burn you if it gets on your skin when its concentrated. I usually have a bottle of vinegar handy too because water won't help and can spread the burn.
Cheers,
Greg.

I

Hi Greg and others,
You raise some good points Greg, I agree that de-greasing and cleaning of parts before de-rusting is a good idea, it keeps the electrolyte cleaner for longer, and should make for a more even rust removal process, but having said that I have found that even oily parts seem to come up o.k. with the electrolytic process providing that they have undergone treatment for a day or so. Thick grease might eventually be broken down too, but I would remove it first for the reasons you have given.
In your step 2, I think your method for mixing up a Caustic Soda solution is somewhat dangerous however. It would be safer to add the flakes of Caustic Soda SLOWLY to some COLD water. This is an exothermic reaction, and so the solution will get hot as you add the flakes. By adding the flakes to the water, if it started to generate enough heat to cause some spitting of solution, any drops of solution will be much weaker in concentration, than if you add the water to all the flakes that are to be dissolved. If you use hot water you run the risk of generating steam as the addition of flakes to the water will push the temperature higher, and it may go above boiling point. If it does, most likely undissolved flakes are likely to spread around, and as they will be wet, nasty alkalai burns are likely.
I agree with most of the rest of your post and I like your idea of using each solution to neutralise each other, but I do think that you may need more than just a few amps if you are de-rusting large parts such as a lathe bed, and need it done in a day or so.

I have not tried Molasses but have used vinegar at full strength very successfully. Greg you use Bi carbonate of Soda, have you ever used Sodium Carbonate - (Washing Soda, aka Lectric Soda)? Any particular reason for using Bicarb Soda?

I sometimes either dip the part if it is small or spray it with metho to assist with the drying before it begins to rust again. I'm not sure, but I think that there must be some fine particles of reduced iron, or maybe the surface is micro etched by the rusting and de-rusting process, which causes the brown haze to appear within seconds of its removal from the process. A stiff brush like a toilet cleaning brush is useful to clean the item down during its final rinse. (Don't ask how I found out about this.)

Another tip could be that epoxy paints are quite tolerant of alkalais, and wouldn't normally misbehave if some leached out of cast iron onto the paintwork. They do go a bit chalky though if exposed to excess Ultra Violet radiation. You can use epoxy as a primer coat, and then go over it with some enamel or polyester for example, if U.V. is an issue.

Hi Stuart, What Ewan said, Cheers,
Rob.

[Stustoys]

If I'm not in a hurry I actually prefer to use molasis rather than electrolsys,
Hi Greg,
Has there been a thread on this?
Does this do it all or just from step 7 onwards?



Aim for the highest amps you can
Hi Ewan, Rob, But I have a 200amp supply ;)

Whats say I aim for 12ishV at around 40amps with dishwasher powder?

Stuart

[Anorak Bob]

I undercoated my Hercus lathe bed, inside and out, before getting to get a colour chart to match the red inside the casting.

BT, if you are listening, can you tell me a close colour, I know you have Dulux colour swatches at work.

Ken

I'm listening KJ. Cast your eyes back here -
http://www.woodworkforums.com/f65/well-went-well-not-161795/index3.html#post1578817

Now, I've had a look at a real life sample of Colorbond Wilderness. I'm at work, not next to my ARL. The colour seems a bit murky on the sample. Call Bluescope on 1800022999 and ask them to send you a colour swatch.

Have a look here also - Colour Atlas (http://www.dulux.com.au/specifier/colour/colour-atlas) Dulux have a colour to match the Colorbond finish.

I have a question. With all this rooting around with electrolysis, why didn't you just sand off the paint, leaving the filler, touch up the filler and repaint the bed?

BT

[neksmerj]

Hi BT, thanks for all your input, I appreciate it.

My lathe was an ex Tech school machine, and the little darlings had over painted it sky blue with what looks like a mop, there was paint everywhere.

I started off with a power wire brush, but this was too tedious so decided to try electrolysis. A new learning exercise as well.

I've got the green paint sorted, it's the red colour inside the bed casting I'm after. I could probably just pick any red, but if I can get a close colour match, I'll feel happier.

Ken

[Anorak Bob]

Sorry KJ,

I stuffed that up:doh:. Had I taken the time to read your question properly the answer would have been different. I have a couple of swatches at home that include red. I'll have a look tonight.

BT

[Ueee]

Thanks Rob and Greg for the info.

I have to say that oil and grease doesn't seem to bother the process, not at higher amps anyway. After spending about 18 hours at 5.5A i pulled the guard out of the bathe this arvo. 99% of the outside paint is gone, but there was still plenty inside. So i carefully positioned an anode in the guard (used clothes pegs to stop it shorting) and let it go for about 2 hours.....All the paint and scum is gone from that area, i just need to move the anode to the other end to get at it.

Why root around with electrolysis BT? Well if Ken hadn't then i would still be daunted by the thought of stripping and cleaning Blondie! Good job Ken and thanks for sharing!

Stu, a mere 5A would do, but i guess if it survives 40 it will survive anything.....

[Steamwhisperer]

Step 8: let it dry and if painting the part prime it right away, if not then give it a good rub with boiled linseed oil or steam cylinder oil if you can get any (Phil?)
Cheers,
Greg.

I

HI Greg,
am watching this one with great interest.
Steam cylinder oil, confident I can get some of that:D

Phil

[kwijibo99]

Hi All,
Rob, Ewan, You're right, given enough time and current the oil will eventually come off but it just slows down the whole process and scadges up your electrolyte.
If you're going to use molasis though you need to get the grease and oil off first because you don't have the heat you get with electrolsys.

Rob, adding the boiling water to the caustic certainly does result in a very energetic reaction but I found that this disolves the caustic more quickly and evenly. I found you get almost as violent a reaction if you add the caustic to hot water but it happens near the top of the bucket rather than the bottom and you increase the chances of getting some on you. You're spot on though that using cold water is by far the safest but with small jobs the stripping works much faster with a hot solution.
Once an old mate and I had to degrease and strip the subframe of a 4hp Sundial engine. We put it in a 44 gallon drum 3/4 full of caustic then lit a fire underneath and let it boil for a while. I remember being as itchy as buggery for the rest of the day and the clothes I was wearing near falling apart the next time the cook washed them but by christ it cleaned the engine good. (I never laid claim to being the sharpest tool in the box :D)

I use bi-carb mainly because I always have some around, I keep a box in the beer fridge to keep it smelling fresh :; and the kids use it when playing mad scientist (vinegar and bi-carb they love it). I'm sure washing soda would work equally well for electrolsys and maybe even for the kids experiments but how will my fridge smell? I personally would never use caustic for electrolsys, it's just too nasty and I couldn't leave the tank full with the kids around. The used electrolyte with bi-carb, and I assume washing soda, is actually very good for your lawn, presumably because of the high iron content but I reckon you would have a dead lawn if you dumped a caustic electrolyte on it so it would have to go down the sewer which probably isn't great either.

I forgot about the brown film, I use a scotchbrite pad for smaller bits and a dunny brush for the larger items, my cook went balistic when I put the black stained brush back in the toilet, she just didn't see the funny side.

Finally, and I think Phil will agree, 600 weight cylinder oil is the hands down, far and away besterest thing for keeping uncoated steel or iron rust free. Boiled linseed oil is nearly as good but it will leave your part sticky for a while afterwards.
The main drawback with cylinder oil is it only comes in 20lt or 205lt drums and a little goes a long way.
Cheers,
Greg.

[Oldneweng]

I have a huge tum tree in my back yard, with a branch hanging over the outside area where I work. I just don't know if it will support the weight of the bed.

Suppose I could throw a rope up and over it, and hang off it to find out.

The things we do in the nature of engineering.

Ken

A mate of mine told me a story from when he was young and silly. It involved a sheep that was not exactly his, nor his mates. The said sheep was tied to a gum branch ready for the knife. It was to be hung from the same branch. The sheep went crazy, did a bolt and snapped the rope that was holding it. My mate and his mate took off after it. Within seconds the gum branch they were under crashed to the ground. It was a huge branch. They let the sheep go free.

I am not sure if tum trees have the same type of behaviour as gum trees.

The events in this story were a huge coincidence. I am not suggesting this would happen. I just thought you would like to hear the story. LOL

Dean

[Greg Q]

Reading through the thread again I found caustic, baking, bi-carb and washing sodas.
Does anyone have a favorite for the test?
Dishwasher powder is caustic isnt it? Woud that do?

-work, +graphite right?

Any current density you'd like me to aim for?

Stuart

p.s. Maybe I should see if I can get this stuff to conduct first. yeah should it should but does it?

To answer your question Stu...i use washing soda simply because it is both better and cheaper than baking soda or drain cleaner. It doesn't take much-only a tablespoon or so in 20 litres of water. the stronger sodas I use for etching aluminium or dissolving the hair of my coven in the drains. Bless their little cotton socks.

From my experience with this process my lessons learnt are have a big enough battery charger to dump 6-8 amps constant power if you are in a hurry, and have lots of electrodes surrounding the rusty object connected by copper wire. The electrolysis process seems to work on line of sight...your electrodes need to see every aspect of your workpiece for effective and fast rust conversion.

The other lesson is: blast the object dry with compressed air/towels/heat guns etc then oil it or paint it to prevent the rather rapid orange blight from forming on your newly rejuvenated surfaces.

Oh...I upgraded my ebay charger's bridge rectifier to take arc welding type loads for rust removal quicker than glacial pace. I think I saw 16 amps, slow popping filmy bubbles, orange scum and the creature from the black lagoon all in the first five minutes. YAMMV

Greg

[Oldneweng]

Hi Greg and others,
You raise some good points Greg, I agree that de-greasing and cleaning of parts before de-rusting is a good idea, it keeps the electrolyte cleaner for longer, and should make for a more even rust removal process, but having said that I have found that even oily parts seem to come up o.k. with the electrolytic process providing that they have undergone treatment for a day or so. Thick grease might eventually be broken down too, but I would remove it first for the reasons you have given.
In your step 2, I think your method for mixing up a Caustic Soda solution is somewhat dangerous however. It would be safer to add the flakes of Caustic Soda SLOWLY to some COLD water. This is an exothermic reaction, and so the solution will get hot as you add the flakes. By adding the flakes to the water, if it started to generate enough heat to cause some spitting of solution, any drops of solution will be much weaker in concentration, than if you add the water to all the flakes that are to be dissolved. If you use hot water you run the risk of generating steam as the addition of flakes to the water will push the temperature higher, and it may go above boiling point. If it does, most likely undissolved flakes are likely to spread around, and as they will be wet, nasty alkalai burns are likely.
I agree with most of the rest of your post and I like your idea of using each solution to neutralise each other, but I do think that you may need more than just a few amps if you are de-rusting large parts such as a lathe bed, and need it done in a day or so.

I have not tried Molasses but have used vinegar at full strength very successfully. Greg you use Bi carbonate of Soda, have you ever used Sodium Carbonate - (Washing Soda, aka Lectric Soda)? Any particular reason for using Bicarb Soda?

I sometimes either dip the part if it is small or spray it with metho to assist with the drying before it begins to rust again. I'm not sure, but I think that there must be some fine particles of reduced iron, or maybe the surface is micro etched by the rusting and de-rusting process, which causes the brown haze to appear within seconds of its removal from the process. A stiff brush like a toilet cleaning brush is useful to clean the item down during its final rinse. (Don't ask how I found out about this.)

Another tip could be that epoxy paints are quite tolerant of alkalais, and wouldn't normally misbehave if some leached out of cast iron onto the paintwork. They do go a bit chalky though if exposed to excess Ultra Violet radiation. You can use epoxy as a primer coat, and then go over it with some enamel or polyester for example, if U.V. is an issue.

Hi Stuart, What Ewan said, Cheers,
Rob.

I agree with the info on making up caustic soda. Just like diluting acid from concentrated acid. Pour conc acid into cold water slowly.

I have this clear memory of Caustic Soda from High School. The soda pieces were shaped like small capsules but flattened on two sides. I distinctly remember that these produced a chilling effect when mixed with water. Nothing I have done since with Caustic Soda had repeated this experience. Maybe it was something else. I mixed up some "pearl caustic" (don't ask me what it is. Just granules.) at work recently. This created some heat.

Caustic Soda can be a very dangerous and damaging chemical. It gets used a lot at work for cleaning. I soaked some laboratory centifuge buckets in caustic for quite a while, some years ago. They were aluminium. I did not know what caustic did to aluminium. It cost $1200.00 to replace them.

Dean

[BobL]

One minor benefit of washing soda is if it is just rust you are cleaning up you can safely dispose of the electrolyte down the drain, your could even put it on your garden or on lawn.
The later is not such a good idea with caustic solutions.

Whatever the electrolyte if it has been used to clean up old painted machinery the paint could contain quite a bit of lead so the electrolyte should probably not be put down the drain.

BTW if you want to stop the object re-rusting, take it out of the electrolyte and wash off the crap and electrolyte with a water jet/hose. If you use a sander or wire brush or you handle it put it back in the bath again to soak and clean any grit or oil off the object and rinse again with ordinary water. Yes, when you remove it, it will start to generate orange rust (Fe2O3) within seconds but that is OK, its even good but don't let it go for too long.
Before doing this you need to have a deionized water bath already at a vigorous boil so you can then dunk the whole thing into the bath and let it boil for an hour or so. Then place the object in a bath of hot (100ºC) mineral oil for half an hour. This will generate a grey submicron layer of greyblack FeO that instead of being flakey will be bonded to the metal. Black FeO is rust resistant and just one treatment like this may last for weeks to months without going orange

This process is actually is a form of metal blueing. Repeated light rusting/boiling (oil bath is only done at the end of the last treatment) generates very fine layers of rust (Fe203) and subsequent boiling in deionised water is one way of blueing the metal. Some loose FeO is formed on teh surface as well and this needs to be taken off with a fine soft wire brush between repeats.It will not affect threads or other precise surfaces as the layers are very thin.

If you repeat this 10 -12 times it will will go a dense blue black like this
http://www.woodworkforums.com/attachments/f189/216240d1342615982-home-made-milling-attachment-toolpostjpg2f.jpg

One stipulation, the water and the bath itself (stainless is best) must be as CLEAN as possible.
Cheap distilled water will not give consistent results and neither will reverse osmosis water, it must be super distilled or deionised water.

The gun bluers recommend using gloves to handle the object as skin oils will kill the process.

[Ropetangler]

Hi All,
Rob, Ewan, You're right, given enough time and current the oil will eventually come off but it just slows down the whole process and scadges up your electrolyte.
If you're going to use molasis though you need to get the grease and oil off first because you don't have the heat you get with electrolsys.

Rob, adding the boiling water to the caustic certainly does result in a very energetic reaction but I found that this disolves the caustic more quickly and evenly. I found you get almost as violent a reaction if you add the caustic to hot water but it happens near the top of the bucket rather than the bottom and you increase the chances of getting some on you. You're spot on though that using cold water is by far the safest but with small jobs the stripping works much faster with a hot solution.Greg.

I agree with all you've said there Greg, but you would be safer heating the solution afterwards like you did on the Sundial engine mentioned below. You had a face shield on, but if you generate lots of heat, your brew can almost explode out of the bucket and shower you and everything nearby with hot caustic solution. If you have a steel bucket, (not galvanised) or a stainless bucket/ jam boiler or similar, you could heat the solution up to boiling point, and it will work very efficiently stripping paint, grease and rust if connected up in an electrolytic cell.


Once an old mate and I had to degrease and strip the subframe of a 4hp Sundial engine. We put it in a 44 gallon drum 3/4 full of caustic then lit a fire underneath and let it boil for a while. I remember being as itchy as buggery for the rest of the day and the clothes I was wearing near falling apart the next time the cook washed them but by christ it cleaned the engine good.Greg.

I can well imagine that it would have


I use bi-carb mainly because I always have some around, I keep a box in the beer fridge to keep it smelling fresh :; and the kids use it when playing mad scientist (vinegar and bi-carb they love it). I'm sure washing soda would work equally well for electrolsys and maybe even for the kids experiments but how will my fridge smell? Greg.

Bicarb Soda does all that and more, it is very useful household cleaner and air freshener, stain remover etc. Washing soda might not help the smell of the fridge, you need to chuck that old cheese out to fix that, but washing soda is the active ingredient of bath salts, but I'm not suggesting that you throw your other half into the de-rusting tank, no matter how warm you make it.:q



I personally would never use caustic for electrolsys, it's just too nasty and I couldn't leave the tank full with the kids around. Greg.
I see where you are coming from, but if you only mix a weak solution, just strong enough to get the required current flow, it wouldn't be too dangerous, but bicarb or washing soda would be safer, especially if the youngsters ever got their hands on the raw chemicals, so I would do the same if I had kids around.



The used electrolyte with bi-carb, and I assume washing soda, is actually very good for your lawn, presumably because of the high iron content but I reckon you would have a dead lawn if you dumped a caustic electrolyte on it so it would have to go down the sewer which probably isn't great either. Greg.

I think it neutralises an acid soil, suppresses the growth of moss and makes more nutrients available to the grass if you have an acid soil. A weak solution of caustic may well work in a similar way, but a strong solution will certainly give you a break from the mowing.:D


I forgot about the brown film, I use a scotchbrite pad for smaller bits and a dunny brush for the larger items, my cook went balistic when I put the black stained brush back in the toilet, she just didn't see the funny side.Greg.

Mine didn't either.:D


Finally, and I think Phil will agree, 600 weight cylinder oil is the hands down, far and away besterest thing for keeping uncoated steel or iron rust free. Boiled linseed oil is nearly as good but it will leave your part sticky for a while afterwards.
The main drawback with cylinder oil is it only comes in 20lt or 205lt drums and a little goes a long way.
Cheers,
Greg.
Have you tried lanolin or any of the lanolin containing compounds like "Lanotec" spelling??? Is the cylinder oil much superior?
Cheers,
Rob

[Steamwhisperer]

HI Gre,
I concur with the steam oil, in fact the brand we use now (Morris Lubricants) actually cleans the surfaces it comes in contact with. It's not flash on painted surfaces, leaves a nasty stain.
The only other downside is the cost :oo:
We are now using Lanotec heavy duty but are still waiting for their new product which is supposed to be better.

Phil

[Ropetangler]

Great post BobL, very informative. I had no idea you could do bluing that way. I must give it a try some time. Would the de-ionised water from Woolworths or K-Mart be up to the job, or do we need specialist suppliers?
I noticed on your photo of what I presume is a ball turning attachment, that you had a welded nut which certainly had not been polished up before the bluing process, but the result was as good as the machined surfaces. The end result looked as good as the SHCScrews, thanks again for the post.
Rob:2tsup:

[BobL]

Great post BobL, very informative. I had no idea you could do bluing that way. I must give it a try some time. Would the de-ionised water from Woolworths or K-Mart be up to the job, or do we need specialist suppliers?
Cheers RT.
Full details of the process I use are in this thread (http://www.woodworkforums.com/f189/home-made-milling-attachment-152165/index3.html). - the description is in post number 16.

A bit of testing has shown me that the deionized water at woolies etc is not always deionized, some of it is distilled. If it really is deionized it is usually OK but you need a lot of it for big pieces. For example to blue that tool post and rotary table holder I used about 2L per boiling, and I "rusted and boiled" the parts 12 times so I used 24 L of water plus a few more for cleaning etc. If you are going to do a lot of blueing it will be worth finding a 20L plastic container and cleaning it up and buying deionized water in bulk. Just look for water purification businesses that sell it in bulk. I recently upgraded my water filter for my coffee machine from sediment filters to reverse osmosis. Adding a deionizing cartridge to that system didn't add much to the cost so I now have high quality DI water on tap - well, not quite - it generates about 12L/hr.


I noticed on your photo of what I presume is a ball turning attachment, that you had a welded nut which certainly had not been polished up before the bluing process, but the result was as good as the machined surfaces. The end result looked as good as the SHCScrews, thanks again for the post.
Rob
The weld does look a bit crappy - I should have brazed it instead but I don't have an oxy. I did polish the weld with the same scotchbrite wheel as I polished the rest of the tool post.
Blueing won't hide any sins, if welding spatter is left on steel blueing will coat nicely so that it turns into black spatter.
BTW I Blued those screws as well.

[Anorak Bob]

Hi BT, thanks for all your input, I appreciate it.

My lathe was an ex Tech school machine, and the little darlings had over painted it sky blue with what looks like a mop, there was paint everywhere.

I started off with a power wire brush, but this was too tedious so decided to try electrolysis. A new learning exercise as well.

I've got the green paint sorted, it's the red colour inside the bed casting I'm after. I could probably just pick any red, but if I can get a close colour match, I'll feel happier.

Ken

KJ,

I had a look at the lathe this morning armed with a PPG icoat* colour card. Crimson R15 is a good match. RAL 3002 Carmine Red is nearly identical.

What did you end up with for green?

BT

* their industrial coatings range.

[neksmerj]

Hi BT,

Forgive my ignorance, what does PPG refer to? If I took your info to a Dulux Trade Centre, could they fix me up?

Another question if I may. I would like to know what treatment is given to the HERCUS name cast into the side of the bed.

ie, what colour is the raised lettering, and what colour is the recessed background. I haven't got one photo of my bed prior to undercoating.

I have also sent you an email.

Ken

[Anorak Bob]

Hi BT,

Forgive my ignorance, what does PPG refer to? If I took your info to a Dulux Trade Centre, could they fix me up?

Another question if I may. I would like to know what treatment is given to the HERCUS name cast into the side of the bed.

ie, what colour is the raised lettering, and what colour is the recessed background. I haven't got one photo of my bed prior to undercoating.

I have also sent you an email.

Ken

One of the oldest paint brands in the market, Taubmans has been painting Australian homes for over 110 years. In 2007 PPG Industries acquired the Taubmans brand. Back in the early 1900s, George Taubman built the company on a foundation of technical superiority. Taubmans' new owners, PPG, also have a long history of applying global technologies to gain a competitive edge.

Dulux will match other brand colours.

Red lettering yellow background.

BT

[neksmerj]

BT. That's great, many thanks for your time. I'm off to my nearest Dulux Trade Centre in the hope I can buy a small tin of Carmine Red RAL 3002.

I'm a little suprized, I seem to remember the red being brighter than Crimson.

Doubt I'll be painting today, it's far too hot, near 40.

The green I chose is Dulux Quit Rust Green Freeze OCH. Would like to know the nearest RAL colour number for future reference.

[neksmerj]

This arvo I visited my local Dulux Trade Centre. They could not match the Carmine Red RAL 3002 paint, it's not on their computer system. In fact, they have very few RAL colour numbers on their system. Couldn't even show me the colour.

Had more luck with the existing tin of Dulux Quit Rust Green Freeze paint. The bloke behind the jump ripped the lid off, removed all traces of skin, and declared the half litre left is perfect.

Just have to get the red paint sorted, and I'm back in business.

Ken

[Anorak Bob]

This arvo I visited my local Dulux Trade Centre. They could not match the Carmine Red RAL 3002 paint, it's not on their computer system. In fact, they have very few RAL colour numbers on their system. Couldn't even show me the colour.

Had more luck with the existing tin of Dulux Quit Rust Green Freeze paint. The bloke behind the jump ripped the lid off, removed all traces of skin, and declared the half litre left is perfect.

Just have to get the red paint sorted, and I'm back in business.

Ken

OK KJ.

Try Dulux RED BOX P04 H9 The closest Dulux has to the Carmine Red in their Colour Specifier Atlas (Series 2).

Hope this helps.

BT

[Oldneweng]

This arvo I visited my local Dulux Trade Centre. They could not match the Carmine Red RAL 3002 paint, it's not on their computer system. In fact, they have very few RAL colour numbers on their system. Couldn't even show me the colour.

Had more luck with the existing tin of Dulux Quit Rust Green Freeze paint. The bloke behind the jump ripped the lid off, removed all traces of skin, and declared the half litre left is perfect.

Just have to get the red paint sorted, and I'm back in business.

Ken

Good to hear that tin of paint is ok. I think the title of this thread is no longer representative of efforts. It is good to read about the techniques used and see the results. I dont think I will be doing my new lathe tho. At 1.5 tonne or so for the whole lathe I don't want to risk that to the large and beautiful gum tree just outside my shed. It was this beauty that sealed the deal on buying our little bit of paradise.

That ball turner is a real inspiration BobL. One of the things I must make. Mind you, I am looking for milling projects as I hope to have my new mill home Saturday night. I just need to make up a frame which will be turned into a cabinet, make some room in my shed and I will be in action. The lathe will take a bit longer to arrange. Still got the old one I suppose.

Dean

[Stustoys]

the graphite slip cloth that Stuart has volunteered to try out sounds well worth the time and effort to try.
Well that didnt work very well.
Got a 15 litre bucket, a rotor and a piece of graphite slip cloth 290 x 150mm.
Added about 4 tablespoons of dishwasher powder.
Not a lot of action
Added 3 tablespoons of bi-carb
Still no a lot of action, amp gauge just moving and a thin wall of bubbles coming off the rotor.
Replace the slip cloth with a piece of 2mm MS 65mm square, current up to 5amps and cooking nicely.
So while if tested with a multi meter the cloth seems to conduct very well, it doesnt do so well when you want to pass some current through it...DMM getting me in trouble again.
I'd say about 30% the graphite has come off the cloth.

Stuart

[neksmerj]

Thanks Stu,

Graphite cloth seemed a good concept, a pity it didn't work. Looks like ms is the go for electrodes.

Ken

[Ueee]

Thanks for the test Stu, bit of a bummer but it was worth a shot.
I have wondered though if carbon fiber would work.......

[neksmerj]

Finally got around to doing some painting today.

Problem 1. Couldn't find my small touch up spray gun, it's just disappeared.
Problem 2. Had to resort to my Paasch airbrush.
Problem 3. Could not get the airbrush to put out paint consistently, had to continually keep adjusting the nozzle.
Problem 4. After washing out the airbrush, realised I'd left both lathe feet inside the house, undercoated, ready for paint.

I'm just putting all this down to old age and stupidity, and hope it doesn't get worse.

A couple more bad, bad pics. The true colour is somewhere in between the two pictures.

Ken

[Anorak Bob]

Where is the lathe going when it's reassembled Ken? The neighbour's carport again or did you build that shed you drew up a year or so ago.?

The colour looks the part.

BT

[neksmerj]

Firstly BT asks, "where's the lathe going when it's finished". Ans, in the lounge room until I get a shed organised.

BT gave me some colours for the red paint inside the Hercus bed. Dulux Crimson R15, Dulux Red Box po4 H9, and RAL 3002 Carmine Red.

Off to get a small tin of Dulux Crimson R15, full gloss, oil based. Problem. The smallest tin was 1litre and priced at over $50, Ouch!

They suggested trying other paint outlets for smaller tins, but to no avail. Min size 1 litre, all over $50.

As a last resort, I went to my local Mitre ten. Same story, however, I was shown a spray tin of Wattyl Kill Rust Epoxy Gloss Enamel, colour Delicious Red. Perfect, especially the $13 price tag. I was initially looking for paint to apply with a brush, but with a bit of judicious masking, I'll get away with a spray can.

Just need to wait for the right weather conditions.

Ken