Electrolysis - A Superior Cleaning Process

[DSEL74]

This is a link to what seems to me to be a very informed view on the process laid out in layman's terms. If it is superior I am not in a position to say…..have a read and be the judge.

Electrolysis Cleaning Method (http://users.eastlink.ca/~pspencer/nsaeta/electrolysis.html)

It is interesting that he says the metal is still eroded or eaten away in this process and discusses the factors that increase and decrease the rate. A lot of people in favour of this process believe that it is non destructive, vs Vinegar, molasses and commercial products which are acidic. According to this it is also going to eat away at the item.

The discussion on Hydrogen embrittlement is also interesting.
Just remember that a crack that starts on the surface will act as a stress riser. In other words stress will concentrate at the crack. After a crack starts it will propagate.

Quotes from other sources on Hydrogen embrittlement.

standard hydrogen embrittlement relief cycle for high strength steel after plating operations (including reverse plating, like electrolysis) is bake at 375 F for 24 hours within 4 hours of plating. If you have an oven that big, have at it. BTW, the time and temp are critical. Too hot and you ruin the temper, too cold or not long enough and you wont drive off (enough) hydrogen.

I agree, would be much better off to bead/sand/shot blast to remove the rust. Shot blasting is the only one that will provide any benefit from a cracking standpoint.


Rust leaves jagged pits in metal. These pits are surrounded by uncorroded metal. These pits themselves can act as stress concentrators, just like a nick or scratch. This is independent of any embrittlement resulting from the chemical changes adjunct to the corrosion.

From a 'planar' viewpoint, the plane which contains all of the rust pits, perhaps a few thousandths thick, is no longer contributing significant stiffness any more, since this plane of the metal is not continuous, but interrupted with pits.

Your best bet is to just carefully grind down past the pits and then re-finish to prevent future corrosion. Abrasive blasting will get the steel 'white' again, but cannot get the surface smooth and free of pits.


Below are some divider callipers that went pop after being placed in a bath.
http://i276.photobucket.com/albums/kk18/masterg65/assorted%20tooling/DSCN1070Large.jpg

Here's a hot tip: DO NOT ever put springs into the electrolytic rust removal bath, or you will find out about "Things that go "snick!" in the night."

Hydrogen embrittlement. The electrolytic bath, and judging from your results the phosphoric acid bath also, infuses hydrogen into the steel. Deadly to springs under tension.

If the steel is a tool steel like high-carbon steel or an alloy steel, I gently bake the hydrogen out in the kitchen oven on 220 deg for 20 minutes after removing the item from the electrolytic bath. Not too hot or you'll draw the temper !

Others say they just leave the tool steel items out in the mid-day summer sun to bake off the hydrogen after electrolysis. This would probably work best in the sunbelt.

P.S. This is absolutely not necessary if the item is cast or wrought iron. Hydrogen embrittlement only happens to certain steels. (Not that you are likely to find anything made of true wrought iron that's less that 100 years old.)






It is all very interesting stuff!

[delbs]

Electrolysis is very interesting, i had 3 hand planes i wanted to de-rust but i didnt have a car battery charger to use. While i was looking for one i also came across this product

Evapo-Rust Australia Home Page (http://www.evapo-rust.com.au/)

a solution that you soak the metal in over a day or two. Then the rust just washes away. Very effective stuff. I should de-rust another piece and post a WIP

[DSEL74]

Electrolysis is very interesting, i had 3 hand planes i wanted to de-rust but i didnt have a car battery charger to use. While i was looking for one i also came across this product

Evapo-Rust Australia Home Page (http://www.evapo-rust.com.au/)

a solution that you soak the metal in over a day or two. Then the rust just washes away. Very effective stuff. I should de-rust another piece and post a WIP


Interested to see that WIP. What is the active ingredient in the product?



Evapo-Rust™ is the only chemistry in the world employing selective chelation for rust removal. Evapo-Rust™ is sewerable in neat form and works at a pH ranging from 6 delivered to 7 as a spent solution.

Chelation is I believe in Molasses, I wonder if the chelator is the same and just more refined??


Light rust is removed in as little as 5 to 30 minutes. Medium rust up to 6 hours, and heavy rust takes up to 24 hours.
Certainly claims to work faster than molasses which they say usually takes 1-4 weeks. at a 1:9 ratio.


The chelator is too expensive to use large quantities in the finished product. An organic chemical that easily loses sulfur to form ferric sulfate was added to remove iron from the iron-chelator complex. This allows the chelator to remove more iron from iron oxide. The sulfur-bearing compound is much less expensive than the chelator and makes Evapo-Rust™ economical to use.Evapo-Rust™ has a chemical carrying capacity of 300grams of pure, dry rust per 5 litres.

The farm grade molasses also has sulphur in it.

[BobL]

The hydrogen embrittlement possibilities in ordinary home electrolysis is a complete phurphy.
Hydrogen embrittlement requires either very high temperatures or pressures or both, neither of which are happening in ordinary electrolysis.
The reason your callipers broke was almost certainly that there was already a small crack present and the electrolysis cleaned out the crack enabling it to propagate - this is a reasonable common event and for folks to blame hydrogen embrittlement.

The removal of metal is possible if;
- the wrong electrolyte is used - acids work great but they should not be used.
- electrolyte is left in the tank too long and exhausted
- nonferrous metals are being treated.clearly
- the article being treated is connected to the wrong electrode which may completely dissolve the metal item.
- High voltages and currents are used - in the eastlink article he recommends 24V which is WAY too high as this will generate too high a current which will in turn break may down the electrolyte into things that harm the metal and generate large volumes of hydrogen gas. He also reckons 4 A is too low whereas I reckon anything higher than 5 A is too high. Sure it takes longer at lower current but it is much safer to do this. I have left many things for two weeks under electrolysis and nothing has happened. All that happens (usually within a couple of days) is the anode gets covered in slime and the current stops flowing. High voltages and currents are also inherently dangerous since this greatly increases the likelihood of sparking which may ignite any hydrogen.

The guy on the eastlink article is not a chemist and some of what he has written attests to this (he also says he had to refer to a relative who is a chemist for advice) so I would treat anything he says with some degree of skepticism.
The reason he uses such large voltages and currents is because he is treating large objects and is finding it hard to get electrolysis happening all over the object. However, instead of increasing the voltage he should use more electrodes and space them equidistant around the and even inside the objects being treated.

Provided low currents <10A and preferably <5A are used, the solution is soft alkaline, and no nasty chemicals or metals are used the process is relatively safe to use on ferrous materials.

[gallegos]

I've done this a few times very successfully but never really found an anode I was happy with... steel fouls very quickly so requires constant cleaning and apparently stainless will kill you. Anybody had success with any other materials?


For the power supply I use a modified computer power supply which is a good option because they are capable or quite high current at 12V and can generally be found for free.

[BobL]

I've done this a few times very successfully but never really found an anode I was happy with... steel fouls very quickly so requires constant cleaning and apparently stainless will kill you. Anybody had success with any other materials?
Yep, carbon arc welder rods work well. Normally you can only buy a 20 pack of these so they can be expensive but if you know a really old school welder he will probably have a few laying around his shed that he no longer uses. They are also often coated withe copper which should be dissolved off otherwise the copper will end up on the cathode.


For the power supply I use a modified computer power supply which is a good option because they are capable or quite high current at 12V and can generally be found for free.
That's what I use but I only add enough electrolyte to generate about 5A.

[DSEL74]

I've done this a few times very successfully but never really found an anode I was happy with... steel fouls very quickly so requires constant cleaning and apparently stainless will kill you. Anybody had success with any other materials?


For the power supply I use a modified computer power supply which is a good option because they are capable or quite high current at 12V and can generally be found for free.



FREE I like FREE!
Computer power supplies come in quite varied specs. Can you provide more details and how was it modified just extended the wires and add gator clips?

[shedhappens]

FREE I like FREE!
Computer power supplies come in quite varied specs. Can you provide more details and how was it modified just extended the wires and add gator clips?

I think you should nut n' bolt all your terminals to reduce the risk of this LiveLeak.com - Checking for a gas leak the right way (http://www.liveleak.com/view?i=1d8_1371006354) :D

[Stustoys]

Depending on your power supply. Just put a jumper on the pins in this link.
Howto: Hotwire a PC power supply (http://4volt.com/Blog/archive/2009/03/12/howto-hotwire-a-pc-power-supply.aspx)(you can use a switch if you like, I just used a bent wire.)
You will likely need a load on 5V line for the power supply to keep running, I just used a dead HDD, I replace it with a 220ohm(?) resistor.
If you felt it was worth the trouble you may also be able to dig out the trim pot to let you control the output V. I can just get mine up to 13.8V as I was using it to float a battery. It wont switch on set that high though.

Stuart

[harty69]

I've done this a few times very successfully but never really found an anode I was happy with... steel fouls very quickly so requires constant cleaning and apparently stainless will kill you. Anybody had success with any other materials?


For the power supply I use a modified computer power supply which is a good option because they are capable or quite high current at 12V and can generally be found for free.

I use lead sheet from the plumbing store and hang it over the side real easy and last for a very long time

Cheers
Harty

[BobL]

I use lead sheet from the plumbing store and hang it over the side real easy and last for a very long time

Cheers
Harty

The problem with that is you the create a solution that has lead in it. It won't be much but I bet it will be well over any disposal regulation.

[Ueee]

Below are some divider callipers that went pop after being placed in a bath.


They just had to be round legs too, didn't they.

I run off a 5a, 12v switchmode driver. Works well, takes a few days but will clean just about anything off. Although the lead may not be recommended i might try a bit.....Will the waste water kill the out of control ivy at the back of the shed? The weak caustic/washing soda mix hasn't......

Cheers,
Ew

[BobL]

They just had to be round legs too, didn't they.

I run off a 5a, 12v switchmode driver. Works well, takes a few days but will clean just about anything off. Although the lead may not be recommended i might try a bit.....Will the waste water kill the out of control ivy at the back of the shed? The weak caustic/washing soda mix hasn't......

No it won't affect plants that much.

Lead is a cumulative poison that affects mental health and IQ at low levels well before gums start receding and teeth and nails fall out, then it takes a lot more to cause internal bleeding and death. Did you know that when we were still using leaded petrol we were about 1/4 of the way along to the lead levels the ancient romans experienced and they were applying leaded salts as makeup and spreading lead acetate jelly on bread because it tasted sweet. The Swiss did some interesting research that showed that prisoners have higher levels of blood than the general population but then so do people from inner city suburbs. Inner city areas and 1960s suburb soils are seriously lead contaminated from the used of leaded paints and the fallout from leaded petrol. Fortunately the rain is not that acidic and current soil chemistry locks that lead in the top 50 cm or so of the soil. However, as we burn more coal and the atmosphere becomes more acidic the increasingly acidic rain will dissolve that lead and send it into the aquifers. This is one of many interesting environmental time bombs hanging over us.

[Steamwhisperer]

No it won't affect plants that much.

Lead is a cumulative poison that affects mental health and IQ at low levels well before gums start receding and teeth and nails fall out, then it takes a lot more to cause internal bleeding and death. Did you know that when we were still using leaded petrol we were about 1/4 of the way along to the lead levels the ancient romans experienced and they were applying leaded salts as makeup and spreading lead acetate jelly on bread because it tasted sweet. The Swiss did some interesting research that showed that prisoners have higher levels of blood than the general population but then so do people from inner city suburbs. Inner city areas and 1960s suburb soils are seriously lead contaminated from the used of leaded paints and the fallout from leaded petrol. Fortunately the rain is not that acidic and current soil chemistry locks that lead in the top 50 cm or so of the soil. However, as we burn more coal and the atmosphere becomes more acidic the increasingly acidic rain will dissolve that lead and send it into the aquifers. This is one of many interesting environmental time bombs hanging over us.

Gees Bob, hopefully I will get hit by a bus and I won't have to worry about all that :D:D

Phil

[Oldneweng]

No it won't affect plants that much.

Lead is a cumulative poison that affects mental health and IQ at low levels well before gums start receding and teeth and nails fall out, then it takes a lot more to cause internal bleeding and death. Did you know that when we were still using leaded petrol we were about 1/4 of the way along to the lead levels the ancient romans experienced and they were applying leaded salts as makeup and spreading lead acetate jelly on bread because it tasted sweet. The Swiss did some interesting research that showed that prisoners have higher levels of blood than the general population but then so do people from inner city suburbs. Inner city areas and 1960s suburb soils are seriously lead contaminated from the used of leaded paints and the fallout from leaded petrol. Fortunately the rain is not that acidic and current soil chemistry locks that lead in the top 50 cm or so of the soil. However, as we burn more coal and the atmosphere becomes more acidic the increasingly acidic rain will dissolve that lead and send it into the aquifers. This is one of many interesting environmental time bombs hanging over us.

I keep wondering about the green paint that is constantly flaking of my roof into the gutters and mostly removed by the filter before it gets to the rainwater tanks that provide all of our domestic water. I have a friend at work who is allways coming up with new disasters like lead etc. It can be scary. I don't believe everything he says but there is still alot of stuff that is going to bite us one day.

One thing that I keep thinking about is that our society is mining products that have been concentrated in small areas over millions of years and now we are slowly dispersing these products all over the surface of the planet. Homoginising so to speak. How much metal etc is laying on the sea floor?

Dean

[BobL]

I keep wondering about the green paint that is constantly flaking of my roof into the gutters and mostly removed by the filter before it gets to the rainwater tanks that provide all of our domestic water. I have a friend at work who is allways coming up with new disasters like lead etc. It can be scary. I don't believe everything he says but there is still alot of stuff that is going to bite us one day.
Before hospitals started being more careful with the disposal of radioactive tracers they used to just wash it down the sink. This has contaminated some lakes and rivers in north america and Europe. Nothing to be alarmed about, . . . . (yet). The fact that this stuff can be detected is because it is radioactive and so it stands out from the background, long term it will also decay and disappear but not so with somethings like lead or cadmium which stay toxic for ever. The problem with non radioactive materials is that being already present in the environment we don't even now have a really good idea what levels are natural and what are introduced by man. There are techniques that can be used to discriminate between the two sources but they are expensive and getting financial support for just doing the background measurements is tough. I tried several times to get funding from governments and Uranium mining companies to map the natural background of uranium around some WA U mines and got nowhere. Of course they are not interested in anything that might point a finger at a company at fault. It will be too late to do background measurements when there are a couple of floods that may start to move the stuff out of the tailings dumps. This is one of the reasons why I retired - it all got too hard and I started thinking like Uee :D


One thing that I keep thinking about is that our society is mining products that have been concentrated in small areas over millions of years and now we are slowly dispersing these products all over the surface of the planet. Homoginising so to speak. How much metal etc is laying on the sea floor?

Heaps. The metal content of rubbish dumps, the ocean and especially some river estuaries will be eventually be worth mining when the prices of metal get high enough.

[Oldneweng]

Before hospitals started being more careful with the disposal of radioactive tracers they used to just wash it down the sink. This has contaminated some lakes and rivers in north america and Europe. Nothing to be alarmed about, . . . . (yet). The fact that this stuff can be detected is because it is radioactive and so it stands out from the background, long term it will also decay and disappear but not so with somethings like lead or cadmium which stay toxic for ever. The problem with non radioactive materials is that being already present in the environment we don't even now have a really good idea what levels are natural and what are introduced by man. There are techniques that can be used to discriminate between the two sources but they are expensive and getting financial support for just doing the background measurements is tough. I tried several times to get funding from governments and Uranium mining companies to map the natural background of uranium around some WA U mines and got nowhere. Of course they are not interested in anything that might point a finger at a company at fault. It will be too late to do background measurements when there are a couple of floods that may start to move the stuff out of the tailings dumps. This is one of the reasons why I retired - it all got too hard and I started thinking like Uee :D



Heaps. The metal content of rubbish dumps, the ocean and especially some river estuaries will be eventually be worth mining when the prices of metal get high enough.

Heaps! That much! I knew it was a lot but Heaps! lol.

Or when the cost of recovery makes it viable. Bring on the nanomachines. Program one to go out and build replicas of itself using materials (atoms) found in the ground and all its copies to do the same. Problem solved in about 3 days so I have heard. Thats recycling at its best!

The amount of supposedly naturally occurring gold in the oceans is enough to finance many developing nations budgets for many ye
destroy the value of gold.

Dean

[Stustoys]

Wiki says there is only about 10–30 parts per quadrillion gold in the ocean. So maybe 45000tons? We've already mined 171 300 tons.
Makes Uraunium mining look good at 3 parts per billion. :D

Stuart

[BobL]

Wiki says there is only about 10–30 parts per quadrillion gold in the ocean. So maybe 45000tons? We've already mined 171 300 tons.
Makes Uraunium mining look good at 3 parts per billion. :D

Stuart

that's just in the water, by ocean I also include the ocean floor and under the ocean floor.
Like on land metals are not distributed evenly on or under the sea floor.
The ooze in the outflow from large rivers will be one area worth targeting.
The Neva river estuary that flows into the Baltic at St Petersburg is very close to being worth mining.

Wiki entry


The Federal Service for Hydrometeorology and Environmental Monitoring of Russia classifies Neva as a "heavily polluted" river. The main pollutants are copper (http://en.wikipedia.org/wiki/Copper), zinc (http://en.wikipedia.org/wiki/Zinc), manganese (http://en.wikipedia.org/wiki/Manganese), nitrites (http://en.wikipedia.org/wiki/Nitrite) and nitrogen (http://en.wikipedia.org/wiki/Nitrogen). The dirtiest tributaries of the Neva are the Mga, Slavyanka, Ohta and Chernaya.[20] (http://en.wikipedia.org/wiki/Neva_River#cite_note-20) Hundreds of factories pour wastewaters into the Neva within St. Petersburg and petroleum (http://en.wikipedia.org/wiki/Petroleum) is regularly transported along the river. The annual influx of pollutants is 80,000 tonnes,[21] (http://en.wikipedia.org/wiki/Neva_River#cite_note-Grinpis-21) and the heaviest polluters are Power-and-heating Plant 2 (Russian (http://en.wikipedia.org/wiki/Russian_language):ТЭЦ-2), "Plastpolymer" and "Obukhov State Plant (http://en.wikipedia.org/wiki/Obukhov_State_Plant)". The biggest polluters in the Leningrad Oblast are the cities of Shlisselburg, Kirovsk and Otradnoye, as well as the Kirov thermal power station (http://en.wikipedia.org/wiki/Thermal_power_station). More than 40 oil spills are registered on the river every year.[22] (http://en.wikipedia.org/wiki/Neva_River#cite_note-Grinpis_2-22) In 2008, the Federal Service of St. Petersburg announced that no beach of Neva is fit for swimming.

[robbo37]

" How much metal etc is laying on the sea floor?"
Dean

Thinking back on my time at sea and the cans of beer we
consumed (particularly between Japan and the Persian Gulf)
it must be enormous.:B

[Stustoys]

that's just in the water, by ocean I also include the ocean floor and under the ocean floor.

Yes yes, I was replying to Deans comments really. The ocean floor is something else. There is a show currently on cable about guys driving under the ice for gold near Namo Alaska using suction dredges.

Stuart

[Michael G]

Heaps. The metal content of rubbish dumps, the ocean and especially some river estuaries will be eventually be worth mining when the prices of metal get high enough.

Researchers worried precious metals lost in e-waste recycling - ABC News (Australian Broadcasting Corporation) (http://www.abc.net.au/news/2013-06-13/researchers-worried-precious-metals-lost-in-e-waste-recycling/4750774)

Michael

[Ueee]

Yes yes, I was replying to Deans comments really. The ocean floor is something else. There is a show currently on cable about guys driving under the ice for gold near Namo Alaska using suction dredges.

Stuart

Driving under the ice? must be some car.......

Bob, whillst i may be a bit blaze about pouring lead laden water on the weeds, and i know "every little bit counts", but i just don't see how what i throw out the back is going to have any real life effects compared to the industrial polluters. I have a decent solar array and drive about the most efficient van i could get.....thats my contribution and i'll happily admit whilst they may make me feel better i know they aren't really enough to make a huge difference.

[BobL]

Driving under the ice? must be some car.......

Bob, whillst i may be a bit blaze about pouring lead laden water on the weeds, and i know "every little bit counts", but i just don't see how what i throw out the back is going to have any real life effects compared to the industrial polluters. I have a decent solar array and drive about the most efficient van i could get.....thats my contribution and i'll happily admit whilst they may make me feel better i know they aren't really enough to make a huge difference.

Yeah I'm the same. I have to actively keep reminding myself that zillions of little people like me and you doing a little is better than not. But hey - I'm no saint. Like the scum that I scraped off the top of my small lead castings (probably a thousand times more lead than you pour on your weeds) - what the hell do we do with that?

The problem is that there are no systems set up to deal with these problems and those that exist are over the top and expensive. An example of this is asbestos disposal.

Back in 2006 I had 10 sheets of fencing asbestos to get rid off. I ring around and the minimum cost for anyone to come and get them was $245 and I had to individually wrap each sheet in 2 layers of thick black builders plastic and the edges sealed with gaffer tape at my expense. I ring around a bit more and find out that there is an asbestos dump at Kwinana about 50 km away and they charge by weight - do I have to wrap them for disposal, the dump people said, "No - but it's a good idea seeing as you have to handle them". So I buy my roll of thick black builders plastic and gaffer tape and seal them up. Put them in the back of my then ageing mitsubishi van and head for the dump. On my way south on the Kwinana freeway I see a guy towing a trailer full of asbestos, not covered, not one sheet sealed, dust pouring off the back. Oh well there's got to be at least one of these aI thought. As I turn off the main drag to the dump where I join a small convoy of vehicles (mainly big trucks) all carrying building waste including asbestos. Not a single vehicle had sealed sheets. Then we go thru a weigh bridge, which is covered in dust, the weigh bridge operator is sitting in a booth the inside of which is covered in half a cm of dust, even his eyebrows were dusty. Drive in convoy on a dirt track up onto a mountain of building rubble, a good portion of which was asbestos, did I see any black builders plastic, not a skerrick. On top of the mountain a D9 is cruising back and forth crushing asbestos sheets, The driver is in a cabin but has no PPE. My little Mitsubish and my 10 small sheets of black plastic covered look totally out of place, I hold my breath dump the sheets and run. Back at the weigh bridge the charge is a princely $40 ? BTW the suburb of Kwinana is only a couple of kms away from that dump - does anyone really care about these people?

So pardon me if I am now somewhat skeptical about the whole asbestos removal process. A few months later there were some renovations on our building at work that uncovered a 6" diam asbestos pipe about 9 ft long, and it had to was removed from the building. The building was sealed and everyone who worked in the building was sent home for a week. A plastic film walk through tunnel about 50 m long was constructed between the location of the pipe and the disposal truck. Dozens of guys in white suits and masks swarm the building, some collecting air samples for weeks after the event - I cannot even begin to think of the cost. I asked a supervisor, where are you taking the asbestos? "The Kwinana Dump Mate" was the reply.

[Oldneweng]

Yeah I'm the same. I keep reminding myself that zillions of little people like me and you doing a little is better than not. But hey - I'm no saint. Like the scum that I scraped off the top of my small lead castings (probably a thousand times more lead than you pour on your weeds) - what the hell do we do with that?

The problem is that there are no systems set up to deal with these problems and those that exist are over the top and expensive. An example of this is asbestos disposal.

Back in 2006 I had 10 sheets of fencing asbestos to get rid off. I ring around and the minimum cost for anyone to come and get them was $245 and I had to individually wrap each sheet in 2 layers of thick black builders plastic and the edges sealed with gaffer tape at my expense. I ring around a bit more and find out that there is an asbestos dump at Kwinana about 50 km away and they charge by weight - do I have to wrap them for disposal, the dump people said, "No - but it's a good idea seeing as you have to handle them". So I buy my roll of thick black builders plastic and gaffer tape and seal them up. Put them in the back of my then ageing mitsubishi van and head for the dump. On my way south on the Kwinana freeway I see a guy towing a trailer full of asbestos, not covered, not one sheet sealed, dust pouring off the back. Oh well there's got to be at least one of these aI thought. As I turn off the main drag to the dump where I join a small convoy of vehicles (mainly big trucks) all carrying building waste including asbestos. Not a single vehicle had sealed sheets. Then we go thru a weigh bridge, which is covered in dust, the weigh bridge operator is sitting in a booth the inside of which is covered in half a cm of dust, even his eyebrows were dusty. Drive in convoy on a dirt track up onto a mountain of building rubble, a good portion of which was asbestos, did I see any black builders plastic, not a skerrick. On top of the mountain a D9 is cruising back and forth crushing asbestos sheets, The driver is in a cabin but has no PPE. My little Mitsubish and my 10 small sheets of black plastic covered look totally out of place, I hold my breath dump the sheets and run. Back at the weigh bridge the charge is a princely $40 ? BTW the suburb of Kwinana is only a couple of kms away from that dump - does anyone really care about these people?

So pardon me if I am now somewhat skeptical about the whole asbestos removal process. A few months later there were some renovations on our building at work that uncovered a 6" diam asbestos pipe about 9 ft long, and it had to was removed from the building. The building was sealed and everyone who worked in the building was sent home for a week. A plastic film walk through tunnel about 50 m long was constructed between the location of the pipe and the disposal truck. Dozens of guys in white suits and masks swarm the building, some collecting air samples for weeks after the event - I cannot even begin to think of the cost. I asked a supervisor, where are you taking the asbestos? "The Kwinana Dump Mate" was the reply.

It would be incorrect for me to think that the purpose of all these regulations regarding the removal and handling of asbestos were to provide employment and money for the companies involved in the process rather than the protection of people in the community, wouldn't it!

I believe that in SA (over the border) the professionals have to be called in for a 2m2 piece. We are lucky that there is a covered trailer parked at our dump (transfer station) for double wrapped parcels of asbestos although I am not sure of the limits.

I started collecting cell type batteries for proper disposal. I tried to find out about disposal locations. I was happy to take them to Adelaide when I was going there. I finally found that it was recommended to take them to the dump.

Radioactive smoke detectors. Now it has been decided that it is to difficult to handle them. Take them to the dump as well.

How would one dispose of lead contaminated water? Two choices I can think of.

High temperature incineration. Not sure if it is suitable.

Take a trip to Port Pirie and give it to someone to water their garden. Lead contaminated? Wont be as bad as the dirt is already Mate.

Dean

[BobL]

High temperature incineration. Not sure if it is suitable.

Lead is an element that cannot be broken down by conventional temperatures even in a high temp furnace unless you could get to about 100 million degrees.
Incineration will send the lead as lead oxide dust into the atmosphere so it will then settle out all over the place.

The lead in the electrolyte will be present as small lead carbonate crystals which are quite insoluble in water so pouring it on the weeds means it will join the insoluble lead in the soil. Only if someone was to put acid onto that area of soil would it move around. Growing vegies in that soil will mean the veggies might pick up a bit of lead dust but so will any vegies growing in suburban solis. Another good idea to wash all veggies before use.

[Oldneweng]

Lead is an element that cannot be broken down by conventional temperatures even in a high temp furnace unless you could get to about 100 million degrees.
Incineration will send the lead as lead oxide dust into the atmosphere so it will then settle out all over the place.

The lead in the electrolyte will be present as small lead carbonate crystals which are quite insoluble in water so pouring it on the weeds means it will join the insoluble lead in the soil. Only if someone was to put acid onto that area of soil would it move around. Growing vegies in that soil will mean the veggies might pick up a bit of lead dust but so will any vegies growing in suburban solis. Another good idea to wash all veggies before use.

So not suitable. I sort of thought that would be the answer.

Would the vegetables actually absorb lead as well as have it on the skin?

We have been trying to grow our own, being out in the country but with pure sand type soil, poor water holding, rabbits, gazillions of birds looking for tasty sprouts, cows ignoring fences and the odd grasshopper plague!

Dean

[BobL]

So not suitable. I sort of thought that would be the answer.

Would the vegetables actually absorb lead as well as have it on the skin?

We have been trying to grow our own, being out in the country but with pure sand type soil, poor water holding, rabbits, gazillions of birds looking for tasty sprouts, cows ignoring fences and the odd grasshopper plague!

Dean

Different plants will pick up different amounts. Lead follows calcium in biological pathways so uptake within the plant structure will occur most in stuff like leafy greens and surprisingly less in root veggies. A bigger problem may result if soil dust is ingested with the plant and the concentrated by an animal (eg milk).

The role of soil stuff on plant surfaces has been largely ignored but as far back as the 60's tobacco companies knew that the primary reason why tobacco is radioactive is because the hairs on tobacco plants hold soil dust so tightly it cannot be easily washed off. Amongst the first genetic modification experiments done on plants were attempts to grow (unsuccessfully) hairless tobacco. It has been estimated that something like 1/3rd of all tobacco causes cancer comes about from the increased radiation exposure caused by breathing in the radioactive component of tobacco.

[Oldneweng]

Different plants will pick up different amounts. Lead follows calcium in biological pathways so uptake within the plant structure will occur most in stuff like leafy greens and surprisingly less in root veggies. A bigger problem may result if soil dust is ingested with the plant and the concentrated by an animal (eg milk).

The role of soil stuff on plant surfaces has been largely ignored but as far back as the 60's tobacco companies knew that the primary reason why tobacco is radioactive is because the hairs on tobacco plants hold soil dust so tightly it cannot be easily washed off. Amongst the first genetic modification experiments done on plants were attempts to grow (unsuccessfully) hairless tobacco. It has been estimated that something like 1/3rd of all tobacco causes cancer comes about from the increased radiation exposure caused by breathing in the radioactive component of tobacco.

Interesting information Bob. Dust can be worse. That is understandable.

I am glad I live where I do. There are still issues, but not as bad as some places. There are very few spray operations in my area. My property is surrounded on three sides by Blue Gum plantations. They spray the boundaries with herbicide (probably roundup) regularly. They (contractors acting under instructions) are very careful to keep 2-3ft from our fences. I wish they would go right to the fence because then our cows would not push against the fences to get to the 2-3ft strip of grass on the other side. That is about the worst of our problems.

Dean

[gallegos]

FREE I like FREE!
Computer power supplies come in quite varied specs. Can you provide more details and how was it modified just extended the wires and add gator clips?

I did mine like this with a switch, led and binding posts on the front for the different voltages.

How to Convert a Computer ATX Power Supply to a Lab Power Supply (http://www.wikihow.com/Convert-a-Computer-ATX-Power-Supply-to-a-Lab-Power-Supply)

[Stustoys]

Driving under the ice? must be some car.......
:doh:




I did mine like this with a switch, led and binding posts on the front for the different voltages.
Thanks for that, I'd never thought about adding "taps" together.


Stuart

[Oldneweng]

I did mine like this with a switch, led and binding posts on the front for the different voltages.

How to Convert a Computer ATX Power Supply to a Lab Power Supply (http://www.wikihow.com/Convert-a-Computer-ATX-Power-Supply-to-a-Lab-Power-Supply)

Thanks for that link. One of my stalled project is a Lab Power Supply based on a simple circuit from the back of a Jaycar CatnDog. It did not work and I have not got back to it. The PC PS is a cheap easy method and sometimes it is easier to have the instruction rather than work things out for yourself.

Dean

[DSEL74]

Ok here are some of my tips on home electrolysis


Use scrap steel for Sacrificial Anode, they work are cheap and no real toxic risks
It works on areas closet to the Anodes fastest (Line of Sight)
Multiple anodes spread out around the item seem to work better and more evenly
The Anodes should have equivalent surface area to the part being cleaned or it will be slower and the annode will need to be scraped clean regularily
Bigger the item/bath the more current required.
It is an inexact science and slight changes in positioning the anode in relation to the part can affect it working.
Distance between annode and part affect conductivity
Water is orange with rusty hydrogen on top when working after a while, when turned off the empty bath settles and the water goes green. No idea why and doubt it matters at all. I did find it an unexpected sight though.
It can take ages and I am unsure what size, current or condition parts said to be done in an hour would be, expect overnight or longer.
Parts come out dirty and need a wash & a brush, don't expect it to come out clean.
If parts are not washed and treated promptly they will flash rust
The Soda Crystal dissolve easily in hot or cold water
No noticeable change in temperature to the bath from the electrolysis. (Done outside and it is bloody cold in Melb at present)



These are my observations so far, and there is plenty more info available on the net on what to do and not to do, how to set up etc.



Lat night I used a 90L tub about half full with 2 anodes and it was very slow drawing under 2amps, left it for around 6Hrs and it did form an orange froth on top and came out with a scummy layer over the whole part. Put it back in today with 4 anodes and the meter jumped straight to over 8amps and the charger shut off, reduced it to 4 anodes and it is drawing about 6amps, been in so far for around 4Hrs.

[DSEL74]

273707273708273709273710
Initial Setup Day 1






Day 2 Before power

273711

After 4 Hrs, followed by a quick stir with a bit of wood
273712273713

[BobL]

Ok here are some of my tips on home electrolysis


Use scrap steel for Sacrificial Anode, they work are cheap and no real toxic risks

Steel anodes still have quite a few problems.
They oxidize or rust as soon as the voltage is applied and as you say need to be cleaned every few hours to maintain a reasonable current - this is the reason it seems to take ages.
The rust contaminates the electrolyte and tanks and makes a real mess and is why the parts come out dirty.

BTW the reason the colour changes from orange to green is that some of the iron in the steel that dissolves away from the anode into the solution is initially in the ferrous state (each atom of iron has lost 2 electrons) and ferrous solutions are green in colour. There should also be some black stuff underneath the orange sludge on the anode. The black stuff is the solid ferrous oxide which eventually gets converted to the ferric oxide (each atom of Fe has lost 3 electrons and is orange in colour), by the oxygen produced near the anode and the atmosphere. The Ferric oxide is insoluble but clings to bubbles in the solution making it look orange and masking the green ferrous colour of the solution. When the current is turned off the Ferric oxide being insoluble precipitates out revealing the ferrous solution.

I have started using Carbon anodes and these are much better than steel. There is no need to clean the electrodes and everything operates a lot cleaner.
You also raise the issue of anode distribution. I find an anode every 20 cm or so around the tank is needed to get an even process.
Also all connects should be done using nuts and bolts (ie no alligator clips). If a clip slips off while the voltage is applied there may be a small spark generated and enough hydrogen around to cause an explosion. Also remember to turn off the power before disconnecting anything.
This problem is exacerbated if, a tall narrow tank is used so use a wide flat tank and make sure the electrolyte fills most of the tank, high voltages/currents are used - there should be no need to use more than 12V and about 10 and preferably ~5A.

Explosions are rare but do happen. There was one last year where someone was de-rusting a truck brake drum in a tall narrow tank and he disconnected the anode before turning the power off. The explosion was a small one but it covered the guy in orange muck and he had to change his trousers.

[Ueee]

The other thing not mentioned is bathing the parts in a weak acid solution (vinegar) after the process. This neutralises any alkalinity, which will cause havoc to any paint applied to the item.
FWIW my bath has never gone green.
Bob where did you get your carbon rods from? I have looked at jewelry supplies for carbon stiring rods but they are pretty pricey when you consider how many are needed.
I generally use just one sheet of steel and turn the job every now and then. I find the slower you go the more even the coverage.
Cheers,
Ew

[BobL]

The other thing not mentioned is bathing the parts in a weak acid solution (vinegar) after the process. This neutralises any alkalinity, which will cause havoc to any paint applied to the item.
I wouldn't use vinegar unless it was something like pure spirit vinegar as it may contain organics that would also need to be removed, a good spray wash with a hose should get the soda out but for me a bit of soda remaining doesn't matter as I let the treated objects rust till I can clearly see an orange patina (just a couple of hours is often enough) and then I convert that to ferric phosphate using phosphoric acid. I then air dry the objects till most of the moisture has evaporate away and then bake in a hot BBQ oven till it is completely dry. Some folks wash just off any remaining sticky residue with Meths and let it air dry.


FWIW my bath has never gone green.
It depends on the type and concentration of the electrolyte.


Bob where did you get your carbon rods from? I have looked at jewelry supplies for carbon stiring rods but they are pretty pricey when you consider how many are needed.
! got a pack of 13 mm diam rods from a welding shop like these for $10 because some of them were broken.
Southern Cross Industrial Supplies - Product Detail: CARBON RODS 13MM PKT (50) (http://www.scis.com.au/Products/PC13.aspx)

I just did a search and found these which would probably do the job
A Man's Toyshop (http://www.amanstoyshop.com.au/ProductDetails.aspx?ProductID=712)
The thinner ones are cheap but beware that they are then more fragile, even the 13 mm ones don't like being dropped.

They have a copper coating which is a PITA to get off - I found sulphuric acid is the best thing to get the copper off with.


I generally use just one sheet of steel and turn the job every now and then. I find the slower you go the more even the coverage.
Yep

[DSEL74]

Could you not run the process in reverse (power wise) to get the copper off? I.E copper plate a sacrificial piece of metal?

[BobL]

Could you not run the process in reverse (power wise) to get the copper off? I.E copper plate a sacrificial piece of metal?

I tried that with the soda electrolyte but it was not that effective (sort of patchy and blotchy) and it took a long time. The ideal solution to do the reverse plating in is sulphuric acid but the sulphuric acid alone will dissolve it off anyway.

[Oldneweng]

I tried that with the soda electrolyte but it was not that effective (sort of patchy and blotchy) and it took a long time. The ideal solution to do the reverse plating in is sulphuric acid but the sulphuric acid alone will dissolve it off anyway.

I know it is more dangerous to use but would nitric acid work better than sulphuric. I was under the impression that nitric was the only common acid that would work properly with copper. May be wrong. It has been known :doh:.

Dean

[BobL]

I know it is more dangerous to use but would nitric acid work better than sulphuric. I was under the impression that nitric was the only common acid that would work properly with copper. May be wrong. It has been known :doh:.

Dean

I thought so too so I tried it and even with the most concentrated nitric possible it was not that fast. I also tried aquarregia which can dissolve gold and it too was slow. Electrolytic copper is very pure and pure metals behave very strangely and not always according to what the text books say. I have dissolved a lot of different and ornery metals in my time and I have to say I was surprised how tough this was.

[meastie]

Hey folks,

There seem to be some experienced people here, I hope someone can help. I'm in the process of tidying up an old 1930's IXL Leader 6x40 lathe and I've been trying out electrolysis for cleaning with mixed results.

I tried a test piece first, a cast facing plate of unknown origin (not for my lathe) to see how it worked. It was painted one side and orange rusted on the bare metal face. I've been using Baking Soda and a car battery charger that puts out 1A. My anode is a cut open baby powder tin, being a new Dad I have lots of these and no money :). On this piece I didn't measure the current over the piece. This cleaning went well but took a very long time. I could see it bubbling and did get the orange froth. After leaving it on over night for most of a week it came out quite clean with very small amounts of black rust remaining. One thing I did notice was a few bubbles that appear to have been in the casting that have opened up as well as a crater in the back of the piece. It was not there before, so I'm a little puzzled by this.

Never one to let something unexplained slow me down :U I went on to a non essential piece of the lathe. Only left on once over night, current was around .65-.7A. A lot of the paint is still there and I'm getting this cratering again. I decided to actually stop and diagnose this time.

Anyone come across this? I'm thinking it's one of two things:

1. The part had actually rusted there under the paint. This doesn't make sense to me though.
2. The part was cast with these imperfections and "bogged" at the factory and then painted for appearance. The process has removed this.

When I get some time in the shed I'll take a few snaps.

Any help gratefully received. Thanks gents.

[BobL]

I tried a test piece first, a cast facing plate of unknown origin (not for my lathe) to see how it worked. It was painted one side and orange rusted on the bare metal face. I've been using Baking Soda and a car battery charger that puts out 1A.
1A is too low and depending on The size of the piece will take a long time. I found 4 to 5A at 12 V seemed to be effective without generating too much gas. The likelihood of explosions increases with greater voltages and currents.


My anode is a cut open baby powder tin, being a new Dad I have lots of these and no money :).
This will be too thin and will erode away very quickly

On this piece I didn't measure the current over the piece. This cleaning went well but took a very long time. I could see it bubbling and did get the orange froth. After leaving it on over night for most of a week it came out quite clean with very small amounts of black rust remaining.
.
.
1. The part had actually rusted there under the paint. This doesn't make sense to me though.
2. The part was cast with these imperfections and "bogged" at the factory and then painted for appearance. The process has removed this.


I'd go for 2. but lets see the pics.

[Oldneweng]

I thought so too so I tried it and even with the most concentrated nitric possible it was not that fast. I also tried aquarregia which can dissolve gold and it too was slow. Electrolytic copper is very pure and pure metals behave very strangely and not always according to what the text books say. I have dissolved a lot of different and ornery metals in my time and I have to say I was surprised how tough this was.

Thanks Bob. Saves me doing the experimenting :D.

Dean

[meastie]

1A is too low and depending on The size of the piece will take a long time. I found 4 to 5A at 12 V seemed to be effective without generating too much gas. The likelihood of explosions increases with greater voltages and currents.


This will be too thing and will erode away very quickly


I'd go for 2. but lets see the pics.

Thank you for your response!

I went for 1A for a number of reasons. It was there, and I was following the ideas of this guy: ELECTROLYTIC RUST REMOVAL (ELECTROLYSIS) (http://myweb.tiscali.co.uk/andyspatch/rust.htm) who favours gentle removal with the theory that more of the part is preserved. It sounded good to me, plus I was a little worried about blowing up the shed!

The formula tin was also used because I had it at hand. It also surrounded the part quite nicely. It was disgusting when done, but seemed to still allow the process to work for as long as I wanted it to run.

I should have also added a 3 to the list;

3. Something I haven't even thought of :)

Onto pictures.

274355274357
274356

I guess it's best described as pitting. It definitely wasn't there in the finish before I started. All shots are of the same site, just from a different angle.

Thanks again

Mike

[Ueee]

Looks like a casting imperfection to me. I would say it was bogged and the process has removed it.

FWIW my tank was a kind of milky green last night. I've never really noticed it being that colour before. It's amazing what you see when you actually look........

Thanks for the links to the rods Bob.

Cheers,
Ew

[BobL]

Thank you for your response!

I went for 1A for a number of reasons. It was there, and I was following the ideas of this guy: ELECTROLYTIC RUST REMOVAL (ELECTROLYSIS) (http://myweb.tiscali.co.uk/andyspatch/rust.htm) who favours gentle removal with the theory that more of the part is preserved. It sounded good to me, plus I was a little worried about blowing up the shed!

I re-read your post and see that you didn't measure the current but just assumed that the charger would output 1A. This is not necessarily the case as the current will depend on the concentration of the electrolyte. The 1A would be for a direct connection so the current was probably less that this.


The formula tin was also used because I had it at hand. It also surrounded the part quite nicely. It was disgusting when done, but seemed to still allow the process to work for as long as I wanted it to run.

Surrounding the part like that is a good idea to get an even electric field around the part being cleaned but you need to be very careful the part does not touch the anode or it will create a short circuit and it may spark.

As to whether the pits were there before or it rusted under the paint, the fact that there is black oxide in the pits suggests the latter. The black oxide is partial reduced red oxide.

[meastie]

I re-read your post and see that you didn't measure the current but just assumed that the charger would output 1A. This is not necessarily the case as the current will depend on the concentration of the electrolyte. The 1A would be for a direct connection so the current was probably less that this.



Surrounding the part like that is a good idea to get an even electric field around the part being cleaned but you need to be very careful the part does not touch the anode or it will create a short circuit and it may spark.

As to whether the pits were there before or it rusted under the paint, the fact that there is black oxide in the pits suggests the latter. The black oxide is partial reduced red oxide.

Bob, thanks again!

On the part photographed it was measured at .65-.7A.

I was very conscious of the part touching and set it up so that it wouldn't to the best of my ability.

So given that it was probably existing rust or filler, what the best tack to take now? Complete the process, fill and paint? What's a good filler?

[DSEL74]

Bob, thanks again!

On the part photographed it was measured at .65-.7A.

I was very conscious of the part touching and set it up so that it wouldn't to the best of my ability.

So given that it was probably existing rust or filler, what the best tack to take now? Complete the process, fill and paint? What's a good filler?



In this case Bob is probably right about it being a rust pocket, however if the part does have filler it will be removed in the process. So either way it is kind of irrelevant if you intend to proceed with this form of cleaning.

Once the part is cleaned, prime it and use standard automotive bog as a filler for the cavities.

[meastie]

In this case Bob is probably right about it being a rust pocket, however if the part does have filler it will be removed in the process. So either way it is kind of irrelevant if you intend to proceed with this form of cleaning.

Once the part is cleaned, prime it and use standard automotive bog as a filler for the cavities.

To be honest I'm undecided about continuing at the moment. It seemed like a great solution at the time because of the perceived low labour requirement. If I have to fix things after that disappears though!

I guess my main concern is loss of strength/integrity of the part, but if there are these rust pockets there already then I'd imagine this isn't an issue either?

The next part I wanted to tackle cleaning is the saddle...

[camoz]

I thought so too so I tried it and even with the most concentrated nitric possible it was not that fast. I also tried aquarregia which can dissolve gold and it too was slow. Electrolytic copper is very pure and pure metals behave very strangely and not always according to what the text books say. I have dissolved a lot of different and ornery metals in my time and I have to say I was surprised how tough this was.

Hey all,

I was going to try the molasses approach today (just to see the difference, I have been using electrolysis for a while now), but as fate would have it, I couldn't break down the part to a point that I could fit it into the smaller bucket that I had (because I was cheap and only bought 2L of molasses, and wanted to go with a 9:1 ratio), anyway back to topic.

I use carbon gouging rods like you guys for electrolysis, but I have gone down a different path as far as getting the copper off. I peel it off like an orange.

It probably takes longer to achieve initially, until you get the hang of it, but without blowing my own trumpet:U, I would say I could probably be an olympic contender in the peeling copper off a gouging rod competition (I have never timed myself, but I will usually do 10 at a time and I get it done quickly).

The key really is getting it started, so this is how I do it:

Starting from the end that is fully covered in copper

274411

I use my angle grinder with a wire wheel attached

274412

to remove a small section (my main concern is forming a lip around the edges for a pair of needle nose pliers or screw driver to lift the edge up and start things off)

274413
this is the tricky part (get this right and you will be done quickly, get it wrong and it becomes fiddly), often I find the most successful approach is to use the pliers to pull the top off like a beer:U, if all else fails use a small flat nose screw driver to tear and lift the copper (but definitely read my warning at the bottom, slipping with the screwdriver could be painful, don't be afraid to change directions. Once you have it started you just literally hold the end of the copper and peel it like an orange, a slightly down and at say 30 degrees off the carbon rod (it's not rocket science though, but obviously you want it to peel down)

274414

End result is carbon rods with no copper.

274415

Your methods sound interesting and less labour intensive, but for the quantity that I need and the fact that I always decide to do these things last minute (no time to wait for the copper to dissolve), it works for me. I thought it might also suit others that are a bit scared to be playing around with other chemicals.

A word of warning though, I don't, but I would highly recommend gloves or at least take care as the copper does become sharp when it is torn and would probably give you the paper cut from hell:C.

Cheers,

Camo

[TKO]

I have removed the post as I notice that it shows part of my photo storage that was not posted, realized that it was through IE 10
which is a pain sorry about this.

Eddie

[Ueee]

I had a moment today, my bath is near the Mars lathe and there was a great big "birds nest" of thickish shavings sitting in the top of the swarf bin. Looking at it i though there must be a pretty decent surface area there.....So i threw it in the bath and hooked it up....instant amp jump and nice bubbles.
They probably won't last long but i have plenty and better to use those than sheet or bar that could be used for something else. I will still get some carbon rods though.
The car parts look good Eddie:2tsup:

Cheers,
Ew

[TKO]

Thanks Ew, I forgot that I was still on IE10 ,I have changed over to Fire Fox which is nearly as bad,
I will try to put them back if I can remember what I posted. This was what I was using for the electrolysis
12 ltr water and 2 good table spoons of washing soda with 5 to6 amps on a battery charger I am
Restoring a Austin AS3 1953. the largest pieces used was brake drums and have had no trouble as yet.

http://i1232.photobucket.com/albums/ff365/aussieddie/A30%20Car/ASE%20car/008-2.jpg
http://i1232.photobucket.com/albums/ff365/aussieddie/A30%20Car/ASE%20car/005-2.jpg

A before and after in Molasses,which I have used for most of the running Gear, I used the molasses back in 1982
on previous restorations.

http://i1232.photobucket.com/albums/ff365/aussieddie/A30%20Car/ASE%20car/001a.jpg
http://i1232.photobucket.com/albums/ff365/aussieddie/A30%20Car/ASE%20car/002c.jpg
http://i1232.photobucket.com/albums/ff365/aussieddie/A30%20Car/ASE%20car/004c-1.jpg
http://i1232.photobucket.com/albums/ff365/aussieddie/A30%20Car/ASE%20car/001c.jpg

All running gear is now primed and painted,
I should put the pics in the forum storage but have trouble posting them from the storage.
its probably me.Post showed other stored photos

Eddie

[BobL]

Hey all,

.
.
.I use carbon gouging rods like you guys for electrolysis, but I have gone down a different path as far as getting the copper off. I peel it off like an orange.
.
.
this is the tricky part (get this right and you will be done quickly, get it wrong and it becomes fiddly), often I find the most successful approach is to use the pliers to pull the top off like a beer:U, if all else fails use a small flat nose screw driver to tear and lift the copper (but definitely read my warning at the bottom, slipping with the screwdriver could be painful, don't be afraid to change directions. Once you have it started you just literally hold the end of the copper and peel it like an orange, a slightly down and at say 30 degrees off the carbon rod (it's not rocket science though, but obviously you want it to peel down) o

I just tried this and it works a treat. Once I got it started to unravel I lay the rod down on a benchtop and held the copper strip with a pair of pliers with one hand and rolled the rod along the bench with the other hand and it came off very easily.
Thanks for the tip - it's much quicker and cleaner that dissolving it off.

[BobL]

I did mine like this with a switch, led and binding posts on the front for the different voltages.

How to Convert a Computer ATX Power Supply to a Lab Power Supply (http://www.wikihow.com/Convert-a-Computer-ATX-Power-Supply-to-a-Lab-Power-Supply)

After seeing this link I decided to tidy up my old ratty computer PS setup according to the link above.

One thing I wanted was an indicator that was more powerful than an LED and maybe do without the usual power resistor or floppy drive attached to the PS to keep the PS running.
The reasons I wanted a more powerful indicator was
- sometimes the circuit shorts or drops out turning the PS off so it's useful to know if it's on or not
- the other thing is I don't like leaving things unnecessarily on at night so I need something reasonably visual that will show up after I turn all the lights off for the night like the orange "compressor on" indicator near the light switch. The shed already has so many red, green and blue indicators that another LED would I fear not show up.

I played around with bike lighting and other small light globes but in the end I came up with a 20W standard 12V downlight but wired to the 5V line which has plenty of spare current.
At 5V the power generated is around 3.5W, still bright enough to show up and not too hot to melt the surround.

BTW the sockets in the standard motherboard plug attached to the PS fit the pins on a 12V downlight very neatly so I just cut a pair of these off and jammed them in an existing hole in the PS case and mounted the globe directly.


275228

275229

275230