What is the best paint for an old machine restoration.

[Buchanan]

The heading says it all. I am restoring an old Acorn tools Shaper and want to repaint it as best possible.
I need a good paint that will resist oil and also stick to the old casting filler. I would like to brush it on as well as spray, with a final cut and buff to get a good polished paint surface. Here are a few photos of the regrinding of the ways. I have reground all the sideways, as most were only milled.

Finally I will scrape them for oil retention. Having a 1 meter surface grinder at work as a luxury. A machine rebuild makes one appreciate accuracy in 3 dimensions.

 

[Charles Lamont]

Tractol ?

 

[Buchanan]

Thanks. It seems like good old enamels stick best. I was wondering how good the two pack paints were, and, if polyurethanes or epoxy's were best.

 

[Wizard69]

You likely already know this but do realize that old paints and fillers, on old machine tools have a very high probability for lead. So you will not want to have young people around when refinishing the paint. Clean up is important too.

Unfortunately machine tools are a tough environment for paints. If you want better life than what a rattle can from the local hardware store can offer you will need to be willing to spend on pro quality paints suitable for machine tools. In that regard you have two basic choices, Urethane and Epoxies. The rational thing to do is to visit some local paint supply stores and get a handle on what they offer.

One example of a high performance "paint" is "Imron" from Dupont used in the transportation industry. Now that is a highly specialized coating system that probably isn't amendable to DIY usage. Rustoleum sells an Epoxy Mastic paint to the industry that is probably better suited to DIY. Try this page: https://www.rustoleum.com/pages/industrial/resources/product-specs/. Generally what you will run into is the better the coating the more difficult to apply. Imron is slightly notorious in this regard requiring special equipment.

 

[DJP]

If your shop is in a high humidity area consider cold galvanizing (zinc) on clean steel surfaces. If it's good enough for the Navy it should provide protection for exposed steel. A top coat of any metal paint should be sufficient and personally I wouldn't worry too much about a perfect automotive gloss finish. You will soon enough be touching up chips once the machine gets used.

 

[Anatol]

I'm a fan of hammerite - it just looks right.
Marine paints are tough, and increasingly, not-so-toxic. Marine enamels make house paint seem like kids watercolors. Awlgrip is a super tough two-part urethane. Use a good metal primer under. Again, marine paints are tough, but expensive.

 

[Buchanan]

Thanks for all the information. I would like this to be a display piece, I don't think it will ever work. So, yes I would like a good polished gloss. I am leaning toward a 2 pack polyurethane.

 

[jhillwig]

I went to Sherwin Williams and they recommended a paint for restoring my bridgeport. It was an epoxy I believe. Whatever it was it worked great.

 

[LSAGuy]

If you use a two part urethane paint be sure to have a good personal air supply. No mask will filter the isocyanates in the paint. More than one auto or airplane painter has died from cyanide poisoning.

 

[JC54]

What a lot of us in the auto trade didn't know at the time was that isocyanates can be absorbed through the skin.. Either stay away from them or be very VERY careful. I know of 2 friends in the trade who had serious problems in later life due to using these paints???? John

 

[Anatol]

isocyanates - ugh! I hate to think of all the poisonous things I've inhaled or have got in through skin, etc ! Resins, solvents... All those miracle materials seem to turn out to have dire qualities. Now the evidence is in about BPA - that's in just about everything and now PTFE (Teflon).

 

[Timehunter]

I rebuild a lot of old machinery and the paint is going to get messed up and stuff caked on it and worn and chipped, etc...
no matter how clean you keep it.
That is if you use it...…
So to settle on one color to keep a little order in life I settled on Battleship Gray.
I went and got a good quality gallon of oil based enamel for metal mixed up and took it home and divided it into quart cans.
While you are at it... a couple gallons of reducer for cleaning and thinning plus some hardener to make it cure a little faster.
You could also put a clear coat on top if you want for a little extra protection.
No need in spending a lot of money on exotic paints it you are going to use it....
But if just a show piece......what the hey...…..

 

[Buchanan]

After all the input I think i Imay change my mind and use good old enamel like they used to in the old days.

If i don't use the machine it will look good any way and if I use it , there are no problems anyway.

 

[rennkafer]

I'm with Timehunter on this, for both of my recent machine overhauls (~1903 Steptoe shaper and 2J Bridgeport) I used Rustoleum Industrial Smoke Gray. I plan to use the machines and being able to easily get paint for touchup's and not having to deal with the temperamental nature of two part paint sold me.

Before and after on the shaper...
View media item 1434View media item 1435View media item 1433View media item 1436

 

[MRA]

> After all the input I think I may change my mind and use good old enamel like they used to in the old days.

This seems a good place to try to tie down the difference between household oil-based paints (which thin with white spirit or turps substitute) and 'enamel paint' - like that sold in tiny pots for model builders - which also thins with white spirit or turps substitute! (Mineral spirits USA, Shellite in Australia, so Google tells me). It seems if it thins with the same stuff, it ought to be the same stuff. Well, it seems like that to me.

I painted my lathe a very tasteful shade of National Trust Green (UK readers will get it) because I found some house paint in B&Q on the cheap. Then the wife saw it and all my supplies got used up on windows, front door... It's OK but a bit soft for a machine, and I'd really need to clean it and do it again one day soon.

 

[Charles Lamont]

The more durable machinery enamels, such as the Tractol I mentioned earlier, and I think Hammerite, seem to be require xylene thinners.

 

[MRA]

Yes, Hammerite thins with acetone or 'cellulose thinners' and is much, much quicker drying than white-spirit based paint.

 

[WOB]

Hammerite is apparently a lacquer which means it will always be susceptible to removal by acetone, xylene, MEK, lacquer thinner, etc. Oil based enamels once cured, resist such solvents much better and allow use of them in cleaning up machine and cutting oil stains that accumulate on machine surfaces.

WOB

 

[Buchanan]

I have used a spirit based enamel before. The results were rather nice . The color was Heritage Green. that was in South Africa in the late 90's . I left the engine behind when we left the country. The enamel had the right look about it. I must have put on 8 coats in the end.

 

[Naiveambition]

I would second epoxy paint. I recently painted a project with sliding surfaces and still no scratches or chips yet. On the plus side is it will already be shiny after spraying , that is very comparable to polished paint.

The one I used was from lauers custom weaponry found at midway.com This purpose is for gun finishes, with a high oil resistance, but could easily adapt to the machine environment. But I will say it is expensive as most good epoxy paints are.
When I was younger they painted a silo at work and the overspray coated a lot of the cars, with a 30 yr warranty it was extremely hard to get the specks off without damaging underlying paint.