Have you ever wondered why there are paint drips on a majority of the brackets and small parts on your GM classic? Believe it or not, what GM did back then was to develop a really cheap and effective method to paint these parts as a subassembly operation near the assembly line. What GM did was have a large tank of water, and they would pour about 1" of cheap black paint on top of the water. The parts came in raw steel, and they were dipped into the paint and hung up to dry on racks. The process was really neat, and the part dipped did not break thru to the water. I saw this first hand at the GM plant in Framingham in 1972. It works great - use Rustoleum enamel in the non spray can for best results. On my Fremont built 70 442, I found drips on pulleys, brackets, and interior parts.
Cool, I'll have to try that!:TU: How thick of a paint layer do you leave on the surface of the water? And can you get the unused paint back in the can?
You need about 1/4" of paint on the surface. Not sure about reusing the paint. Try a 5 gallon bucket, just the right size for most parts.
It allows you enough depth to dip the part in completely. You will go first through the layer of paint and into the water and as you withdraw the part, the paint will again coat the part. You use much less paint this way.
So you would dip the part through the paint into the water, then as you pull the part back out, the paint coats the wet part? Im just trying to understand this. It sounds interesting to me but Im not getting it.
Yep, that's the idea. Crappy cheap black paint floating on top of the water. That's the way I understand the process.
I must have read the 1st post too fast and missed this. It makes a little more sense to me now. But now my question is, what purpose does the water serve?
Using water simply saves paint.....you could dip a part into a 5 gallon bucket full of paint, or you can get the same result dipping the part through only a 1/4" layer of paint floating on top of water.
I've been painting parts like this for a long time, works fantastic for coil springs! I usually have 1/2" to 1" of paint on top of the water, rust-o-leum oil based seems to work the best, just SLOWLY insert the part thru the paint until submerged then SLOWLY pull back out, be sure to have somewhere to hang the part and something to catch the dripping paint so as to not cover your floor. I've tried different ways of saving what paint I didn't use, after painting the parts then sitting the "bucket" outside in the winter and letting the water freeze then pouring the paint off the top seems to work best. Laugh if you want, works great!! :laugh: I normally use a "kitchen" type trash can as its deeper for the springs, put in a trash bag, bungee cord around the top, fill 3/4 or better with water then add the paint, when done you can pull the bag out, poke a hole in the bottom, and let the water come out, if there isn't much paint left it will stick to the bag for zero clean up!! :TU:
Or I could just pour a 1/4" layer of paint in anything without any water underneath and get the same result, couldnt I?o No: Again, Im just trying to understand why they did this with the large tanks of water.
So when you do this, the part first goes through the paint, then into the water, and then back out through the paint?
Yes, the paint will stick to the part on the way thru, if you go slowly you will completely cover the part on the way thru. the paint and water will not mix, pull it back thru then hang up to dry.
What if the part is deeper than the 1/4 inch? This way you can submerge the whole part, especially if it's a long piece, and only use 1/4 inch of paint at a time instead of a whole bucket. My question is, why not just spray it?
Because of the quote from the first post, I did not see any need for the water. And nobody explained what the purpose of the water was or clarified the process in a way that made sense to me untill John answered my last question. :idea2: I get it now, but I think I will stick to spray bombing.
This is a :gp: . Never fails that I learn something new here. I had heard of this but could never quite grasp the concept of dipping a part into water that you are painting. When spraying I go to great lengths to eliminate any amount of moisture. Definitely helps explain the appearance of some factory finishes. I'll probably stick to spray cans too but someday may try it just to demonstrate the logic defying process.
You ever get a drop of water on a freshly painted part and notice how the water beads up, rather than mixing in with the paint? Pretty much the same, just with alot more drops of water. With the paint being oil based, the 2 will not mix together.
The water was used because there was 95% water and 5% paint in the tank. It was a cheap and easy way to coat the parts. Be aware that the amount of rust protection applied was minimal....just enough to keep the rust away until the car was sold. The fasteners came in wire sided pallets of thousands. The bolts were black oxide, and sprayed with oil. The paint dipping station was right down the line from my station, and if I had not seen it, I would not belive it either. However, the strangest process was the leaded seams process for the A pillars and roof joints....super nasty!
I read about this technique in one of Jennifer's Mustang Monthly magazines. Someone wrote into Bob Perkins (a noted concours judge and restorer) about the correct black for brackets and fans. He said that Ford would dump all kinds of crappy, excess paint in the dip tank. So the shade of black varied tremendously depending on what the line workers poured into the vat. Nothing goes to waste in a car plant I guess
