Specifically in inaccessible boxed in areas. I heard on one of the TV shows that there is a new process to powder coat primer. This would be exceptional on a Brookville or similar body to protect the raw bare metal from future rust if it works. With the fine granular powder and electrostatic charge it is supposed to draw in the powder into inaccessible areas. Has anyone here heard of the process or have any information on it as I know there are some professional powder coaters here? Will the powder stick to and protect un-blasted metal?
I'd be more than a little skeptical ... I know from personal experience that powder will stick to the first charged surface it sees. It can be a real chore to get it into recesses and holes you can see, if you're talking about 'blind' areas good luck. As to it sticking, as long as the metal is totally clean and dry I see much less of an issue. Generally the more 'texture' you have the better it will stick, a mill finish will give decent adhesion. Any trace of any kind of oil (even fingerprints) will hurt adhesion.
I run a small powdercoating buisness. That said, powder can stick to raw metal in enclosed areas. I powdercoated my Brookville deck lid to get the inside of it covered and protected. Obviously it has to fit in an oven to cure. Doing a body can be a bit difficult. Sent from my SM-G965U using The H.A.M.B. mobile app
Why not have the body E coated? It will coat every surface, inside and out. When ever I have a body or body parts chemically stripped I also have it E coated for long term protection. Jim
What is the size of the powder, like talcum powder or coarser? You are the expert here, or at least the only person that has chimed in with experience. Doesn't the electrostatic charge draw in powder, like between pinch welds? Or is the powder coarser and not fine like baby powder?
I just had my 46 Olds frame powder coated after it was thoroughly sandblasted. All the 'hard to get' and other {Seen} accessible areas were also primed prior to coating with finished frame turning out better than expected. For the inaccessible {Unseen} boxed areas , originally open 'C' sections, I'll be using a long nozzle to spray rust proofing compound into cavities. For sandwiched areas I'll use light machine oil so that it's drawn in by capillary action, that way it won't rust from inside between the layers of metal.
No Expert here but have done a fair bit of powdercoating and my experience has been that it is difficult to get it into nooks and crannies it would much rather go to the nearest surface. There's no way it's getting into a pinch weld. Remember electricity follows the path of least resistance. It's a bit courser than talcum.
For the most part powder is fine, like baby powder. It adheres to metal electrostatically. That said, when it comes to sharp corners edges, holes... it can be difficult to get coverage. Those areas attract less powder because of the Faraday cage effect. I find some colors of powder adhere better than others. Also, there are techniques to help get around these effects. Like with paint, you can get too much or too little powder on the metal. When I did my 32 deck lid, I just blasted it all over the inside of it hoping to get coverage. Probably got too much in areas that you can not see.
There's two techniques that I've used to get coverage into areas where the powder won't easily go. One is to apply a second coat after curing the first coat. The coated areas are now 'insulated' with coating while the bare areas don't have to 'compete' for attraction as much. This still won't guarantee 100% coverage into all recesses but will improve it. Appearance can suffer however, so I usually won't use this method if any part of the finished product is visible. The second method is to pre-heat the part to 250 degrees and spray the powder on the still-heated part. I don't use the electrostatic charge as it will 'pull' the powder away from the areas I'm trying to coat. The hot surface will partially melt the coating causing it to stick, so the coating can be applied into areas where it might not go if using the charge. The downside is it's difficult to control coating thickness into those areas without having excess thickness on the more open areas, you can get runs. I also use this method for parts that I want an extra-thick coating on; think battery trays. I'll apply up to four coats this way, giving a thick coating like it's been 'dipped' but far tougher. You can also use this method to repair flaws in the finish without fully stripping the part. Wet sand the flaws out, then apply another coat. It does take a bit of practice to apply coating without runs, I'd suggest doing a few practice bits before doing finished parts.
If you are talking about areas inside a boxed frame, I would just get some Por15 or similar product and use a long wand to pull/push through the frame. You will have to have an opening of some kind no matter what you do. You could incorporate scre in plugs that can be removed for coating the inside. If you want to E-coat a body, you might contact Dearborn Duece. They have a company that e coats their bodies "upon request", so maybe they could steer you in a helpful direction. http://www.dearborndeuce32.com/whyecoat.html