Gggggggggggggrrrrrrrrrrrrrrrrrr

[Daddles]

Now I'm really grumpy :mad:

Yeah, I've been playing boat builder again :rolleyes:

Working on Redback's sailing bits. Much manufacturing and sanding. Things going well ... sort of, well, by my standards anyway :p

Wednesday. I coated the rudder, c/b, mast and spars with epoxy (West - only doing one coat of poxy, yes Mik, I know, but you'll understand when we finally get to talk about it)

Wednesday arvo, wednesday night, thursday, thursday night and friday morning, it's cold and wet - what happened to summer?:(

Friday arvo, it's nice and warm, so I scrubbed the bits down with me scourer and amonia to get rid off the waxy blush. Then got into sanding things.
The rudder and c/b sanded nicely - bit of the wax left to clog the paper but nothing to worry about.
Then I started on the mast. Well, instant cloggy paper. Ah well, methinks, I just didn't scrub off the blush properly - I was getting a bit slack by the time I got to them. I continued to sand.
Then I realised WHY the paper was getting clogged. The ruddy poxy was only semi cured - still a tiny bit rubbery. And how did I spot this? The rotten stuff started rolling off the wood like rubber cement will. :mad:

Now I'm in too minds as to what happened.

The immediate guess is that it's been too cold and wet and the poxy just needed more time to set. Possible, though with two days under its belt, I'm wary - guess I'll know by sunday.

I did have to do a second mix so perhaps I cocked up the mixture - I weigh my poxy rather than use the pumps so the mix is usually accurate ... unless I mess up the maths.

The third possibility is this one - the mast and spars were made out of oregon. These were shaped and sanded late last year, and left to sit until now. Resin had exuded from the timber over that time - the timber was covered in little balls. It sanded off nicely, but would this have affected the poxy?

I'm betting number two ... and guess I'll know by sunday. Anyone else like to make a guess? Especially about the resin theory.

Richard

[Boatmik]

Now I'm really grumpy :mad:

Yeah, I've been playing boat builder again :rolleyes:

Wednesday. I coated the rudder, c/b, mast and spars with epoxy (West - only doing one coat of poxy, yes Mik, I know, but you'll understand when we finally get to talk about it)

Wednesday arvo, wednesday night, thursday, thursday night and friday morning, it's cold and wet - what happened to summer?:(

Then I started on the mast. Well, instant cloggy paper. Ah well, methinks, I just didn't scrub off the blush properly - I was getting a bit slack by the time I got to them. I continued to sand.
Then I realised WHY the paper was getting clogged. The ruddy poxy was only semi cured - still a tiny bit rubbery. And how did I spot this? The rotten stuff started rolling off the wood like rubber cement will. :mad:

Now I'm in too minds as to what happened.

The immediate guess is that it's been too cold and wet and the poxy just needed more time to set. Possible, though with two days under its belt, I'm wary - guess I'll know by sunday.

I did have to do a second mix so perhaps I cocked up the mixture - I weigh my poxy rather than use the pumps so the mix is usually accurate ... unless I mess up the maths.

The third possibility is this one - the mast and spars were made out of oregon. These were shaped and sanded late last year, and left to sit until now. Resin had exuded from the timber over that time - the timber was covered in little balls. It sanded off nicely, but would this have affected the poxy?

I'm betting number two ... and guess I'll know by sunday. Anyone else like to make a guess? Especially about the resin theory.

Richard
Hi Richard,

It is down to number 2.

For it to cure on some parts but not others ALMOST certainly indicates either that the poxy either
1/ wasn't measured properly
2/ wasn't mixed properly.

As far as a problem of manufacture - I have never seen epoxy not cure for this reason. People generally swear on a stack of bibles that they did everything perfectly (me too!!) but when they mix up another quantity carefully from the same containers the see that it goes off fine (me too!!!)

And it went off OK on the other bits.
_______________________

The surface that you put it on can effect the surface FINISH hugely - if there is contamination you can end up with greater or smaller amounts of fish-eying - where the poxy refuses to wet the surface evenly so pulls back from some areas and piles up in others - but it always goes off.

There is a small chance that something else could have happened but in thousands of batches used and tens of thousands of batches sold almost every problem has come from not mixing or measuring carefully - and the same materials work fine the next time round when more care is used.
___________________________

The general rule of thumb is if you are down on hardener it is likely to cure EVENTUALLY - maybe a week, maybe a month maybe in 10 years.

If there is too much hardener it is unlikely to ever cure.

There is a few percentage margin in getting the quantities right but we always tell people you have to be PRECISE - that way there will not be problems.
___________________________

Sharpen up a cabinet scraper old bean and get the sludgy stuff off - maybe wait till Sunday just to get an idea of what is happening. Probably worth scrubbing the surface with a brush and acetone, letting it dry for a bit and poxying again.
___________________________

BTW I am very unlikely to agree that one coat only is ever warranted. It is so easy just to put the proper 2 or three on at the same time.

One coat doesn't give you any of the advantages of using epoxy - it will be a bit dry in some areas and you will sand through in quite a few places with the end result that you haven't protected the timber at all.

You really need the two (or better three) coats to seal the surface and allow enough meat for sanding.

It is easy anyhow to apply in one process with no extra sanding

Wait for the first coat to go a reasonably tacky then roll on the second coat. And so too for the third.

As you complete each coat hold the roller so it cant rotate and slide it slowly and gently along the surface to slick it off - popping all the bubbles and getting rid of the texture left by rolling.

This might all sound rather cold and clinical, but I do feel for you - I have been there a few times. And it doesn't feel better that it was my fault each time!!!

MIK

[bitingmidge]

What Mik says!!

Only double!

You know how I have copped a bagging on this forum from some people who reckon that precision in mix isn't important? Well like Mik I haven't seen a problem that wasn't mix related either.

But don't feel too bad. I didn't want to provide negative publicity to a manufacturer as a result of my incorrect use of his product on the Puddleduck thread, but let's just say that's the same effect you get when you pile layer apon layer of waterbased epoxy highbuild without waiting for it to tack off.

No it wasn't me, it was a well-meaning professional painter friend who knew far more than me: he just hadn't used the product before, and didn't believe the instructions.

It WAS me who spent an entire day with a cabinet scraper, removing $20.00 worth of rubber though from hull #1.

ALWAYS use epoxy products STRICTLY in accordance with the instructions, even when you are really tired.

On the other hand, you could move to where it's always fine and warm!

Cheers,

P
:D :D :D

[Daddles]

Like I said, I use electronic scales to weigh the mix, so it's hard to get things wrong unless your mental maths goes screwy:rolleyes: I was using a brush to slurp the poxy over the mast and used that to mix the stuff. I wondered at the time if this wasn't a bad move. I reckon it might have been, reckon that's more likely than a bit of brain fade on the maths, mainly because I wondered what got sucked into the brush at the start of mixing and didn't get mixed into the rest of it - tongue depressors only from now on, though why I used the brush in the first place will remain a mystery I'd rather not delve into. Ah well, I'll get stuck into it in the next day or two and then see what I have.

Neither of you are picking on the resin coming out of the timber, which was the variable that had me stumped - I'd more or less accepted that I'd got the mix wrong somehow.

Thanks
Richard

[bitingmidge]

Ahh yes!

The well known stirring stick made from fibres of unknown Asian origin trick!

We may have found your problem! I don't think the timber gum is the problem, unless you are sanding off cured resin and getting into the gum. You should easily be able to tell if that is the case by the loverly fresh aroma.

Oregon sap is quite distinctive, and cannot be mistaken (in an olfactory sense) for epoxy dust!

Cheers,

P (Furniture scrapers are your friends)

[Boatmik]

On the other hand, you could move to where it's always fine and warm!

Cheers,

P
:D :D :D

Weren't we just deciding that weather had nothing to do with it?

Fine and warm plus lots of water genertes tropical cyclones - so don't get tooooo cocky!

MIK

[Daddles]

What worried me was Midge looking into storm sails for the Puddleducks ...:eek:

Richard

[Aberdeen]

Poor Richard
I was still hoping to have been invited over by now for the turnover - sad state of affairs......... I thought there might be an issue with the sap situation..... will watch the thread and hope you get lucky.....

[Boatmik]

Poor Richard
I was still hoping to have been invited over by now for the turnover - sad state of affairs......... I thought there might be an issue with the sap situation..... will watch the thread and hope you get lucky.....

Oh Dear Old Chap
You can't blame the sap
Unless of course
By "Sap" mean "Chap"

Operator error I fear
Has caused many a tear
Bitter experience
Has turned me religious.

(with apologies to John Donne)

[Daddles]

Mik, perhaps you need to wear a respirator when working with poxy :rolleyes:

Well, me mast is now back to bare timber ... mostly. Sheesh, nothing like restoring a mast that's only been in a boat the once, and that to see if it'll fit into the step:(

I used a scraper to take off the poxy. Rather easy really, until I hit the bits that had cured properly (about 10% of the mast). Still took a lot of time. Then I worked her over with me mouse sander (love me mouse sander - sometimes I even use it for things Black and Decker imagined a user to be doing :rolleyes: ). Finally, an assault with paper held on a spongy sanding block ... and it's almost as nice as when I first started dammit:(

I'm trying to pretend the spars don't exist ... or at least fooling them that if I stand outside the shed and wave a piece of sandpaper in the air, they'll magically become smooth ;)

I'll get onto the spars about half past this cuppa tea :D

Richard

[scottyk]

I have mixed epoxy for laying a plank on in the cold moulding method, stapled it down and cleaned it up.
Next day, staples come out and plank comes off.......bugger.
So I am with all the others, we all mix it wrong sometimes. I use pumps so I have just totally forgotten, makes a bloody mess!.
Scotty

[Daddles]

Those bloody pumps. I've bought three sets of the things now and everyone of them has failed within two 4l kits. That's one reason why I use the scales. Trouble is, you need some sort of pump to get the muck out of the pot in a controlable manner - pouring makes it hard to get the right amount and also wastes poxy as it pours down the side of the pot or you add too much so have to add more of the other etc.

Why can't they make a single pack poxy?

Richard

Yes Midge, you can make that four sets of pumps because the Bote Cote ones only pretended to put out the same amount with each pump:(

[bitingmidge]

Yes Midge, you can make that four sets of pumps because the Bote Cote ones only pretended to put out the same amount with each pump:(
You'll find that all the pumps are made by the same plastics company, they were designed for dispensing sauces in the food industry, so don't like it when the resin goes a bit stiff in the cooler weather (not that I know anything about that!).

Here's a tip: buy some cheap paper cups. I happen to have a few thousand of them left over from when I was in the food game, (along with some plastic tubs as well). The plastic tubs are great for mixing bog by the way.

If you go to a party supplier, (or Woolies) you can buy hundreds of them for not much, or find an office with a cafe bar and sift through their rubbish bins. Those little plastic cups with the ribs on them make easy measuring.

Don't bother counting the pumps, just fill up to the mark.

So if you are weighing the stuff, how come you are blaming the pumps eh??

P :D :D :D (Laughing with you, so you don't cry!)

[Boatmik]

P :D :D :D (Laughing with you, so you don't cry!)
Er, I didn't notice Richard laughing. He looked a bit down at the mouth really.

:-)

OK - seriously - Midge is right - pumps were made for pumping sauce and mustard which are a lot thinner than pox.

Answer is to warm the resin.

Do this only with quality resin systems that are high solids - ie no solvents.

Simply put a lightbulb - a weak one is enough - in a box of some sort and put the bottles of resin and hardener in. Switch it on at breakfast time and when you get out there 20 mins later the resin is thin enough to pump reliably.

If you are doing a lot of work like Richard - make a box out of cheapo ply with a hinged lid and put in a lightbulb and switch - make sure there is enough space so the bulb doesn't touch the plastic containers - an inch is enough. Click it on as you walk into the workshop

Or if you are mendicant like moi - use a cardboard box and one of those lightbulb in cages with cord that you use to look under your car. and just chuck it in the cardboard box.

The pumps will now not only work but last long enough to do a boat or two. Also the resin is much easier to put on the surfaces smoothly.

And Richard - don't be too mean about those $12/pr Bote Cote Pumps - I haven't had any prob getting the mixes right (when I count correctly!). And you can buy 3 1/2 sets for every one of some other resin manufacturers.

They work great with tomato sauce too!

Boatmik

[Boatmik]

Why can't they make a single pack poxy?

Richard :(

They do - but it's a right bugger to get out of the bottles.

[Daddles]

When I say the pumps 'fail', I mean they stopped pumping for some reason or started pumping intermittantly. I use the pumps to pump into the mixing pot on the scales and I find I can add a gram of resin or hardener quite easily using them, or shoosh out quite a bit. When I started doing this, I realised just how inaccurate the pumps are, but the last two sets just developed air leaks or something and would only drag up the poxy intermittantly. Most annoying - really, using the scales isn't pedantry, it's self preservation. Mind you, it helps that I've already got a set of electronic scales, being a bit of a scrooge, I'd balk at racing out and spending $70 on a set (till the first failed mix now that I know how useful they are).

Interestingly, the pumps we used at TAFE never seemed to give a problem. However, they were in daily and large quatity use - when you've got two boats being build side by side by teams of ten blokes, you can go through a lot of poxy in an evening (yes, and none at all some nights:rolleyes: ).

Richard

[durwood]

just a more point you may consider,

If the instructions state measurements by proportions by volume 2-1 etc. Weighing the components may not give you an accurate match. Often the epoxy paint is a different weight per litre than the hardener.

As to those who think the measuring is not inportant look at it this way

There is a dance, boys and girls, no problem while you can get a couple together, if the is too many of one sex then you have a whole lot of them left out of the loop.

two pack materials need the right number of molecules to join with, any excess and they mess the mix up and stop it being as good as it should be.

[Slavo]

There is a dance, boys and girls, no problem while you can get a couple together, if the is too many of one sex then you have a whole lot of them left out of the loop.
What if it is one of those dances where all the boys are on one side of the room and all the girls on the other, and no one on the dance floor.:D

[Daddles]

just a more point you may consider,

If the instructions state measurements by proportions by volume 2-1 etc. Weighing the components may not give you an accurate match. Often the epoxy paint is a different weight per litre than the hardener.


Not a problem with the glues mate, at least, not with West. I think it's the same with Bote Cote.

Richard

[durwood]

The chemists who research these products come up with instructions which usually take into consideration who may be using them. Thats why instructions may be given in volume not weight.

Its more likely a user will have a measuring stick or a container to metre out the proportions than have access to a set of scales especially digital ones.

Paints especially are touchy, if it says something follow it.

I think using a brush to stir it may have been your downfall they hold a lot of material, hard to get out of the hair mixing but easily wiped out when brushing on.

The other NO -No is using it when the temperature is low. Anthing below 15 degrees C and it won't go hard. Its actually handy to know if you have some left over seal it up put it in the fridge and you can use it next day after you bring it back to room temp. (some last a week mixed when put in a fridge.

[Daddles]

Its actually handy to know if you have some left over seal it up put it in the fridge and you can use it next day after you bring it back to room temp. (some last a week mixed when put in a fridge.

ARRRGGGGHHHHH

Why do you always find out about these things AFTER you need them.

I painted Sixpence with 2 pack polyeurethane. I have to paint outdoors. The last coat was done with the sun in a shocking position and I didn't realise until after I started that I couldn't see what I was doing (literally couldn't see the paint building up on the boat) and so had to spray by guesswork. Naturally, instead of the nice, glossy coat that's so easy to get with this paint (which I achieved on the previous layer of course), I've got dry patches. You only see them with the light at the right angle, but ... Of course, I could just give her another coat ... but don't have enough paint and with the price of the stuff, can't afford to buy some more just for 'looks' sake. The ironic part is, with that last coat, I had a lot left over. If I'd known that trick, I would have put it in the fridge and if I'd got away with it, could have given her another coat the next day - with the excess from that last coat and the little bit left, I probably would have had enough to do a full coat.

Ah well. Another lesson learnt (dammit, I hate vertical learning curves).

She's going to be a gorgeous boat, just not a showboat. Was never going to be a showboat actually, but this paint job falls below what I'm capable of and so is disappointing. Theoretically, I should go ahead and repaint it, but as the boat has a sound layer of paint, I'd only be doing the extra coat or two for looks and with the price of the stuff and my financial position, that's not an option (seriously, I'm already spending money I technically don't have for boatbuilding). Besides, it's the bit that's in the water. I doubt anyone will ever notice (and I fluked getting the top strakes right;) ).

One thought is to have a go at the paint with a can of cut and polish. Anyone tried that? **whoops, missed another straw**:rolleyes:

Richard

boat builder ordinaire

[durwood]

Daddles,
You can polish Polyurethane no problem.

If its peely, dull or rough dry spray cut it back with fine wet and Dry (wet) P1500 would be ideal but P1200 OK.

There is special compound for 2 pack paint, the Auto trade does mainly 2 pack work now and they would have some if you have a friendly Panel Beater you know get him to give you a sample to try. You can do it by hand but a Buff machine is easier. Best done the next day but after a week the paint is so hard it gets way harder. As you say its under the water line so its not important but any cutting and buffing would make an improvement.


Watch the edges keep to the flat surfaces rubbing and buffing, you only see faults on the flat bits anyway.

In future remember 2 packs always have a pot life ( time it stays usable after its mixed with hardener.) usually 4 to 6 hours. on normal days 24degree or so, less in hot weather and longer in colder until it 15 degrees when it usually spits the dummy.

You can put a second coat onto a first coat usually after about 20 minutes but you have a few hours normally if you need them. Once the paint gets past wet ( its becomes tacky) its safe to recoat it. All 2 packs can be piled on top of one another as long as you leave this tack off time and you won't have a problem with them because they have hardener in them to set them all off. Its called "wet on wet" appliction, good for doing jobs quickly (no rubbing ) but you loose a bit of the possible gloss level.

Also, don't be afraid to get rid of any big disasters while the paint is wet.

If it stuffs up big time, get a rag with the thinner on it and wash off the wet paint, it won't hurt the previous dry coats ( they have gone hard and will not resoften) you will have a mess for a few minutes but after a second wipe over with a clean soaked rag you should be back ready to spray again. This time avoiding the reason you stuffed up the first time. A lot quicker than letting it dry and rubbing away the problem ( especially if it was runs )

[journeyman Mick]

Richard,
the epoxy paints I've used you could whack in the freezer overnight (or over lunch) to extend the potlife. The two pack polyurethanes had slightly longer potlifes when put in the freezer but there's no way you'd get them to stay liquid overnight. So it could've been much, much worse, you might've put all the leftover paint in the gun and whacked it into the freezer to find out the next day that you had to buy a new pot of paint and a new spray gun:eek: .

Mick

[Daddles]

You will all no doubt be ecstatic to know that I've stripped back and sanded all the dud poxy, recoated with a good mix, sanded that and have given the mast, spars, etc their first coat of varnish. But don't get too excited. I should have given the lot a light sand and their second coat today, but was too bloody lazy :rolleyes:

The whole lot looks really trick. Be a pity to discover how badly it all works :eek:

Richard

I don't build boats, I create realtime disasters:eek: