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Tips

Sand blasting trunk deck BAD,________? GOOD?

I use a combination of stuff. I start with strong paint remove that I get at the auto body simply store and paint and scrape with that first. After and during that I use lacquer thinner in a can with a brush or sometimes in a spray bottle (danger Will Roberson) to remove the buildup of paint remover and crud in the cracks. Next I use very fine sand you can get at any concrete store for about 8.00 a 100lb bag with about 100psi. I go over everything and not too close or you could warp the panel even with the light sand. You will get a feel for it; it not glamorous work. The sand provides a nice soft etched surface plus it knocks everything off the surface. If there is bondo everywhere, I use some more paint remover on that to soften it up. In extreme cases, I will use a small torch to get bondo off, but that can warp the panel, so I only use that very sparingly. Last I go over the panels again with lacquer thinner in can with about a 3 inch paint bush to remove unwanted chemicals, plus I blow dry the stuff out of those tight spots. Be careful when you use paint remover because it dries and with moister will re-activate, plus it is nasty stuff and will burn your skin.
 
If you do use sand, please get a good quality respirator (not just a cheap paper mask). Blasting with real sand produces extremely tiny, extremely sharp particles of quartz that can't even be seen with the naked eye, but will seriously mess up your lungs if you breathe them. Google silicosis to learn more.

Just a few hours probably won't reduce your lung capacity enough to notice, it can take many years of exposure to produce symptoms. But it does damage your lungs even if you don't notice, and COPD is no fun at all.

There are lots of other blasting mediums available that don't contain silica. I don't know which one to suggest, but "Black Beauty" (made from coal slag) has been suggested to me. I'm guessing you would want to use the finest grade and possibly reduced air pressure when doing sheet metal.
 
If you're not removing rust and just want to remove paint, stripper will work fine by itself. Sand the paint with 80 grit or coarser just to brake the surface. Then apply the stripper by the intructions. What I learned to do is cover or wrap the part your stripping in plastic. A cheap plastic drop cloth works well. This keeps the stripper from drying out and will usually take it right down to metal with the first application. Lift the plastic and check after about and hour. You should be able to remove everything with a plastic scraper or putty knife. Wash the part off with soap and water, dry it, then sand off what ever residue you have left. Wipe the part down with a metal prep (acid etch) the its ready for primer. If you have to sand blast keep the air pressure as low as possible. Once you warp a panel its hard to shrink it back.
 
I stripped the front side of my TR6 using the Eastwood stripper.

I really like black beauty. I use extra fine in my booth. VERY low free silica, good cutting action, good life, good cost.

I used the "old" stuff from my booth in my pressure pot to do the back side of my TR6 bonnet and boot. I used 75 psi at the blasting tip, kept the blasting tip at an angle, and kept the blasting tip moving.

DO NOT try to achieve immediate results. If you'll keep moving the heat build up will be less of a factor.

Good Luck,
Tim
 
you can get soda blast media, glass beads and walnut shell media at Harbor freight tools. I used duponts star blast on my boot deck, the under side, after I had all but finished the body work on the out side, thought I took it easy but still warped the flat pannel, I wouldnt use sand, soda blasting would be the best not to warp it, put down a big blue tarp, if you can hang the tarp up against a wall and do the blasting there you can reclaim the media many times, but each time you will have less. thats if you dont have a blasting cabnet

Hondo
 
Pretty much good advice all around here. I've not used walnut shells but most of the rest. Beads are finicky but warp little and will remove rust but expensive. Soda does not warp much if at all but does not remove any rust. Black beauty (extra fine) does a nice job at removing rust, is cheap and easy to use but <span style="font-weight: bold">it will warp</span> the panel. I've not had much luck shrinking the warps back into shape with a wet cloth but perhaps I don't know how to do it properly.
I try to keep blasting confined to corners and edges and use chemical strippers and rust removers/ neutralizers on the flat areas and then coat with RustLock, POR 15, or the like..
 
The trunk deck in question is a replacement I purchased on Ebay. The original had both lower corners rotted out and had the right rear crunched at one one time. I tried to repair it but the skill level needed to fabricate the corners with the butterfly curves and folded under edges ended up being beyond my skill level. After hours of cutting, welding, grinding etc, I opted for the used replacement. I have chemically stripped the replacement as recommended. I have a fair sized oil can type dent in the center, and unlike my original, the deck is not tight to the X brace on the underside. Once again, I'm not sure how to deal with the separation of the upper layer to the brace. Frustration level increases daily. For the first time in 7 years I'm considering bailing from this project.
 
Here's my amateur opinion. It shouldn't be a difficult fix unless someone has stretched it by trying to beat the dent back into place.
Remove the x brace. Other than flatness in the dent itself, there should be enough shape in the panel to prevent oil-canning. There is 1/2 inch or so of crown from front to back and side to side in the lid. Look for the source of the dent, a crease or sharp spot. If you find one, and you should, tap it with a hammer and dolly. Don't tap anywhere else. When you fix (flatten) the crease, the dent should pop back. You can often help it with your hand.
Shape the x brace to the lid and re-install. It should have 1/4 to 3/8 gap all around with the pads tight to the lid and the brace.
Tom
 
The brace appears to be spot welded to the panel at the corners. Am I about to open another can of worms?
 
bnw, I think I've got an early trunk lid. No raised hinge pads, flat inner cross brace. Its rust free . You called me last week. Kevin @ TC RV 943 4050
 
bnw said:
The brace appears to be spot welded to the panel at the corners. Am I about to open another can of worms?
Sorry can't help here. The later lids with the raised plinths were bolted. I thought the early lids were bolted too but don't have one to check and may be mistaken.
Tom
 
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