-
Welcome back Guest! Did you know you can mentor other members here at H-M? If not, please check out our Relaunch of Hobby Machinist Mentoring Program!
Powder coating
- Thread starter savarin
- Start date
Derf, Looks like you have been doing this for a little while. This is exactly how I do it.
You do nice work!
Interesting on the standard masking tape. I had not tried that trick yet. I have been using the high heat stuff. Thanks.
Some food for thought:
Trichloroethane(1,1,1,Tech) has been outlawed for years, justifiably so. I do miss it though, in certain applications and still have some on the shelf, although it requires some seriously careful handling. Been using it since the sixties, so a little more exposure ain't gonna kill me much sooner..... And, it does clean metal and removes oils deep in the pores of a casting for painting, &c. There is still nothing to compare.
I bring this up for a couple of reasons.
First off, the really good Tap Magic, the kind no longer available, has this as a component. As well as some other shop fluids that are NLA. But for us old timers, there may still be some on the shelf.
Secondly, there is NO paint, or any other finish, that will stand up to it. If it will turn aluminium to powder, paint doesn't stand a chance. Even powder coating.
Please understand, I am not denigrating the project, by any means. But if you do have some of this on the shelf, painted surfaces are a has-been. I have a Grizzly from the '90s, a G1550 9X20. Tiawanese, rather than mainland China. As good as the paint is, there are places on the headstock where there isn't any. So I'm sloppy when I'm rushed, big deal. The point is, if there is any of this stuff around, the paint isn't.
For what it's worth, when Tap Magic was taken off the shelf, I had a friend sold me several cans. Of the old stuff. Because it works, well. The new stuff don't.
Trichloroethane(1,1,1,Tech) has been outlawed for years, justifiably so. I do miss it though, in certain applications and still have some on the shelf, although it requires some seriously careful handling. Been using it since the sixties, so a little more exposure ain't gonna kill me much sooner..... And, it does clean metal and removes oils deep in the pores of a casting for painting, &c. There is still nothing to compare.
I bring this up for a couple of reasons.
First off, the really good Tap Magic, the kind no longer available, has this as a component. As well as some other shop fluids that are NLA. But for us old timers, there may still be some on the shelf.
Secondly, there is NO paint, or any other finish, that will stand up to it. If it will turn aluminium to powder, paint doesn't stand a chance. Even powder coating.
Please understand, I am not denigrating the project, by any means. But if you do have some of this on the shelf, painted surfaces are a has-been. I have a Grizzly from the '90s, a G1550 9X20. Tiawanese, rather than mainland China. As good as the paint is, there are places on the headstock where there isn't any. So I'm sloppy when I'm rushed, big deal. The point is, if there is any of this stuff around, the paint isn't.
For what it's worth, when Tap Magic was taken off the shelf, I had a friend sold me several cans. Of the old stuff. Because it works, well. The new stuff don't.
Bill Hudson
I have to ask what cutting fluid you using.
I don't think I'd risk the warping, It may not happen, but if it does you're stuck with it. Chinese castings A bit like their paint. I'd use a decent enamel.
Those parts look great.
I'm wondering if you used any "Bondo" type filler anywhere?
My question is, will powder coating over Bondo come out well?
Bondo is not compatible with the heat, it will simply fall off. But there is a filler that is just for powder coating, it's called "Lab Metal". It's very similar to the old lacquer spot putty but it has metal fillers in it. I did use it in one spot on the cross slide where someone ran it in to the chuck and left some deep gouges. It seems to fill very solidly, but it does not feather out well around the edges.
These gouges were about 1/16" deep, and although with the filler they didn't totally dissappear, it looks better than they were. If I was to get particular and do a blemish free job, I would simply wet sand and coat again just like you would do with paint. The biggest thing is just sanding down all the sand cast bumps and irregularities. Once in a while you might find an inclusion in the casting that will just have to be filled because it is too deep to grind out.
These gouges were about 1/16" deep, and although with the filler they didn't totally dissappear, it looks better than they were. If I was to get particular and do a blemish free job, I would simply wet sand and coat again just like you would do with paint. The biggest thing is just sanding down all the sand cast bumps and irregularities. Once in a while you might find an inclusion in the casting that will just have to be filled because it is too deep to grind out.
I believe the chemical in Tapmatic was trichloroethylene. It really was a great tapping fluid. It made a sizzling sound as I was tapping. I made the mistake of using on aluminum once and smoke spiraled up from the tapped hole.
I used to buy trichloroethylene by the gallon from an industrial chemical supply house for degreasing. It was deemed a carcinogen and no longer available so I switched to trichloroethane but that was not nearly as effective. Both were eventually banned for being involved in ozone depletion.
