Checking the inside of my Tormach coolant tank, I find the paint coming off in sheets as big as my hand. My coolant isn't that aggressive, so I think the problem is just sub-standard paint.

Rather than invest in a new tank, I plan to repaint the inside of this one, and I'm looking for advice on which paint to use. Would plain old Rustoleum hold up? I'm pretty sure something like POR-15 would do very well, but that's an expensive option.

Any suggestions?

When I rebuilt my Rockwell lathe, I repainted the entire machine and all the parts with Oil-based floor paint. It goes on a bit thicker than any latex/water-based and has withstood all of the coolant and oils I've been able to subject it to. I've dropped tools in the tray repeatedly and it takes all the abuse I can give it without chipping. Also, I must mention that that machine sits in a non-insulated garage that goes through some intense thermals. No chipping/flaking at all.

You can find the oil-based floor paint at any Home Depot/Lowes or even Walmart. It's usually less than $10 USD per quart, and I used about a half of a quart for the entire machine. Make sure to apply it within the first day or two of them mixing the paint so that the oil is evenly distributed. It tends to separate after that. Using it later on down the road, make sure to mix it thoroughly.

Hope this helps.

v/r

How about the paint boat dealers sell to paint steel hulls and running gear, etc. That is pretty tough paint from what I hear.

I repainted the entire machine and all the parts with Oil-based floor paint.

What kind of prep did you do, Swede? Surface cleaning, primer, etc? Your mention of floor paint is the first I've heard. Over on the PM site they seem to be big on Sherwin-Williams industrial paint. I've used floor paint from HD on my (amazingly enough) garden shed floor and it's held up really well, but that was on plywood.

Randy

What kind of prep did you do, Swede? Surface cleaning, primer, etc? Your mention of floor paint is the first I've heard. Over on the PM site they seem to be big on Sherwin-Williams industrial paint. I've used floor paint from HD on my (amazingly enough) garden shed floor and it's held up really well, but that was on plywood.

Randy


i restored an old craftsman/atlas lathe and used sherwin williams industrial enamel alkyd. it went on easy and looked great. unfortunately i sold the lathe before i even got a chance to use it but while assembling it, the finish seemed very tough. i tried to find information on sherwin williams web site but couldn't. it is what they recommended for machinery and heavy industrial use when i went in to the store.

i was able to spray it directly on the metal. the heavy iron was sand blasted (not the ways) and the light parts were bead blasted at a low pressure. all parts were sprayed with acetone and allowed to dry before the finish was sprayed.

here's a before and after pic:

http://img.photobucket.com/albums/v654/300sniper/lathecompare.jpg




as far as the inside of the coolant reservoir, i'd look at the por 15 fuel tank sealer. the floor paint is one i haven't even though about but sounds like a decent idea also.

A bit more costly but you'll NEVER have to touch it again. Have it powder coated. The charge includes prep in the form of sand and bead blasting. THey can mask off what you don't want coated.

THe stuff is essentially bullet proof when it comse to road rash and rust prevention. Our cam gridner was painted over and over. WE did powder coat and it still looks like new after 4-5 years.

300sniper, beautiful job on the lathe! And NC Cams, thanks for the powder coating suggestion. In my last job I did have things powder coated and it is very durable (and look at the trouble the Teutels have scraping the stuff off their motorcycle parts after they forget to tell the powder coater what to mask... :) )

But I'm going in a whole 'nuther direction for now. The Tormach tank is obviously intended to have two compartments--the first as a settling basin for chips and to contain the floating tramp oil, and the second for the pump. But that concept only works if the dividers are sealed to the walls. As it is, they are only tacked in place and the tramp oil fouls the whole tank.

Based on my favorable experience with PVC pipe and sheet in making my spray etching tanks, I'm building my own coolant tank out of a piece of 18" I.D. low-head (0.20" wall) PVC pipe. The input section will be a piece of 6" pipe. The big advantage for me, since I can't weld, is that PVC is easily bondable to a liquid-tight seam. I can bond on fittings, clear tube for a sight glass, etc. and never worry about them leaking.

Randy