Todays question

[jlaird]

Ok, lets say I got this thing home and striped out, down to the last nut bolt and screw. Only the tub remains. Now what.

Have it diped?
Media blasted? Sand? Glass beads? What is soda? I can and will of course farm this job out. No way to do it here.

What happens next? Primer on everything, all over? What kind. Professional application or spray bombs? What kind?

Then of course any remaining body work. Professional primer of some type. Seal the seams, yes. Prime again then or color.

So this is really two questions. Cleaning to bare metal and primeing while work is in progress. Does not seem to me that a proper job can be done with just striping, to many corners and hard to reach spots? The last one I did was striped in a tank then directly to the painter. I was out of town for this so missed all the fun.

 

[dklawson]

I'm not trying to be glib about this but if you're going to farm out the bodywork and painting I'd discuss your stripping and refinishing options with them to see what their experience and preference is/are.

You've opened up a large number of topics and there will be a multitude of opinions based on peoples' personal experiences. I'll offer my own below.

1) Dipped and phosphate coated is great but expensive. Some people will tell you the acid comes out of the seams for years to come. I have not personally seen this on the GT6 bonnet I had done this way. If you media blast stick with baking soda on all the flat panels or you'll warp them (contrary to popular belief that warping is heat related... it's mechanical work hardening of the surfaces inducing stresses). Baking soda imparts less energy to the surface so it won't warp but it is slower.

2) Do not spray with rattle-cans (except for the odd loose piece). Choose your top coat and buy a primer that is compatible with it. If you paint parts/panels yourself and this will be a long process, consider epoxy primers as they seal against moisture better. If the body work will be done quickly consider etch primer followed by high-build as it sticks well and generally costs less.

3) Yes, apply seam sealer. It's paintable. I prefer to prime, seam seal, prime over the seam sealer then top coat.

 

[jlaird]

Well, now I think that nice answer begs another question. Without diping or meda blasting how do you get things satisfactorly to bare metal. How do you keep things from rusting while the unit is in work and how effective is this this methoid what ever it is. Would guess sanding pad and and wire brush on a drill unit?

 

[dklawson]

When doing this at home I chemically strip one panel at a time. I apply whatever chemical and mechanical means are necessary to remove any rust. Following that I acid wash the panel to leave a phosphate coating and spray primer on it for protection.

I don't like regular sanding pads but have had good results with the big 5-1/4" ScotchBrite disks available for drills and orbital sanders.

Incidentally, an acquaintance of mine suggested that on my next restoration I try his method of chemical stripping. He applies a gel type stripper and promptly covers it with Saran wrap to seal in the solvents. He says the stripper works much better that way.

 

[jlaird]

What the heck is an acid wash? This sounds like the way I will go as I can do it myself. What do you then prime with to hold it till you can do the whole body, you have a gun and all?

 

[spritenut]

I have had great results with media blasting. (at a shop)
They use low pressure and plastic beads, but it comes out of a large hose.
The place that blasts also epoxy primes which I recommend.
You can do body work on top of the epoxy primer.
Just bang out any large dents beofre it goes to the blaster.

 

[dklawson]

Acid washing is the application of any number of products containing phosphoric acid. You keep the panel wet until the rust is removed and the metal turns a light charcoal grey color. This typically indicates you've left a coating of iron or zinc phosphate behind. It also leaves the surface etched which provides a good "tooth" for primer to adhere to.

Products that are commonly used to acid wash are Oxi-Solve, Ospho, Metal Ready (from POR), and several "generic" products from sources like "The Right Stuff".

I mentioned earlier that you could either use an etch primer or epoxy to protect the treated bare metal. As Spritenut said, you can do bodywork on top of epoxy... and it protects well against moisture. If you anticipate taking a long time to do your own bodywork, that's the way I'd go. The only drawback I know about epoxy is that for some paint systems it's a bit more expensive. Yes, you'll need a spray gun (and compressor) to apply it.