What kind of paint did you use on your lathe rebuild.
I have used three different types of paints in my builds. In all cases, I stripped back to raw castings, filled/sanded with Bondo, then used a rattle-can automotive primer. The biggest problem with the paint jobs from both mainland China and Taiwan is that they use a chalky brittle body fill to smooth the castings, and any impact against that surface will cause the filler to crumble leaving a nasty wound to the paint. This is why I strip back and re-fill.
For the
custom stand I built for the PM1340, I went with an Industrial polyamide epoxy from Sherwin-Williams called
Macropoxy 646. The member here Anazi built a stand for his 1340 similar to mine, used the same product and raved about it. It would be best applied with spray if you're looking to get a flat wrinkle-free surface. I rolled it on my lathe stand sicnee I wasn't looking for an "automotive" finish, and the stuff is absolutely impervious once fully cured. It is available in gallons and can be colorized to any color you'd like. It is not cheap, but if you set up a "commercial account" with S-W, the prices is basically half off. Gallon cans is the minimum size and with both parts, you're looking at something like $250 even with a commercial account. It cleans up with VM&P Naphtha.
For the repainting of
my PM1340 lathe, I used a single-part polyurethane product recommended to me by Tom Lipton (OxTools on YouTube) called
Steel-It. It's a clear poly with powdered stainless steel mixed into it. If you like
the color ( I do ) then this is a terrific product - almost as durable as the S-W Macropoxy, and a lot easier to use since is single part. It also flows out better than the S-W products if you're using brush or roller. It's available in quarts and gallons and rattle-cans. I love this paint and plan to use it again on my CNC build. Once fully cured, it has stood up to every solvent I've thrown at it with the exception of Acetone (which will soften this paint).
Contact the manufacturer to find a distributor - McMaster carries a knock-off product, but it's not as good.
On
my PM935 mill build, I used another S-W product recommended by Keith Rucker (Vintage Machinery on YouTube) called
Direct-to-Metal Alkyd Enamel. This is a high build alkyd enamel available in gallons that can be color matched to anything. It does NOT brush or roll well if you're after a decent flat finish, and it takes several weeks to cure. I tried brushing, stripped that off, tried rolling, stripped that off, and finally pulled out my air-assisted airless Graco which left a nice finish. Light colors will stain when way oil is left on the surface for a few days, and Acetone with soften and dull the finish.
Of the three, assuming you like the dark warm charcoal color of the Steel-it, that is the product I recommend. It also comes in a two part epoxy version which I might try using on my CNC build.
Hope this helps. Anxious to see photos of your 940.
