Sandblasting the Bed

[Chaparralman1974]

Hey everyone!

Ok, so I am getting ready to move onto the bed in my project. Foolishly, I had to learn the hard way about sandblasting sheet metal....I ruined the hood by having it blasted by someone who didn't know what the were doing. On the bed, I was wondering if I could take a different approach. I was thinking that I could get the bottom and the inside of the bed only sandblasted. I would do the outsides with my SCT and a DA. Given all of the weird contours and such, this would save me a tremendous amount of time and effort. As the bed walls are double layered, do you think it would be ok to do it this way?


The floor needs to be cleaned up anyway so that it can be painted. I will be painting the entire floor black like it was originally. The underside will get epoxy primered (or rustoleum...not sure yet) then followed up with raptor liner.

Thanks, Clay

[Grounded63]

You should be able to have them blast the the top of the rails, insides, frt/rear jamb areas, and the bottom edges/wheel well flanges.

With most respectable/knowledgeable media blast places. You should be able to ask them to only strip the areas. That they know they can strip with out damaging the panels. Usually jambs/edges are fair game. But broader flat/low crown areas are off limits to places that don't specialize in car body's. If inner/interior areas are blasted, that has bracing that exposes an outer skin. The exposed outer skin areas will be heat shinked from blasting. While the outer skin areas behind the bracing will be unaffected. This is one possible issue you need to be aware of, when having body panels media blasted.

[mongocanfly]

("The exposed outer skin areas will be heat shinked from blasting.")

Actually no,not necessarily....here's Robert's post on this
http://67-72chevytrucks.com/vboard/s...d.php?t=647269
Blasting causes the metal to stretch..its like millions of tiny hammers hitting the panel
Heat is not the issue.. using sand also isn't a good idea, walnut or coal slag are better
And yes,someone not knowing what they're doing can ruin a panel..
You also don't want to sandblast that wood floor,,,the blaster will eat that wood up..
I had my truck blasted, it turned out great except for the doors..they made a mess of those..
I have another that I need blasted but I'm only letting them do the impossible to get to parts..the rest I'll strip by hand..
On yours. I wouldn't have any issue with doing the inside bed walls and wheel tubs... but it needs to have epoxy primer put on it after you get it to bare metal..then top coat.....not sure how good raptor will stick to wood if you go that route

[Chaparralman1974]

I was planning to epoxy everything right away. Also, I was going to tell them to stay as far away from the wood as possible. I can clean up the metal rails with a wire wheel if need be. I was just trying to save some time and aggravation by getting all of the unseen areas blasted. I will definitely be using a DA / SCT combo on the sides.

Regarding the raptor liner, everything that I have read says that it will stick to wood. However, I can always just use the raptor on the metal stuff and then paint over the wood on the bottom. Maybe that would be the better option? I am not going for perfection on the bottom, but I do want it to look clean and neat as I have spent so much time on the chassis as well.


Clay

[Chaparralman1974]

Maybe I should just say screw the blasting and try to just DA the paint enough to recoat it???

[LS short box]

On my projects I DA the large flat areas and then sand blast the tight areas you can't get at with the DA.
I use a 30 lb HB pressure sand blaster. Sand from the lumber yard.
I would completely disassemble the bed. Wheel wells. Box sides. Front panel.

[Grounded63]

Originally Posted by mongocanfly

("The exposed outer skin areas will be heat shinked from blasting.")

Actually no,not necessarily....here's Robert's post on this
http://67-72chevytrucks.com/vboard/s...d.php?t=647269
Blasting causes the metal to stretch..its like millions of tiny hammers hitting the panel
Heat is not the issue.. using sand also isn't a good idea, walnut or coal slag are better

" Actually no,not necessarily " doesn't really sound like a definitive answer. It sounds like what you're wanting to imply, is called plannishing.

Coal slag is just as aggressive as sand, possibly more so. Use it in my blasting cabinet, great stuff.

I've been doing paint and bodywork for more than 30 yrs now. Media blasting is a fiction based process. It creates heat, pretty much the law of physics . . . I've absolutely seen and had to repair, heat shrink damage. On media blasted panels. Your not going to repair low spots or a lack of crown, on a panel by shrinking them more.

I also used to paint a lot of custom sport bikes. I would send the plastic fairings out to get media blasted. Never had an issue with them stretching. But, once the guy that knew what he was doing left there. They definitely had excessive surface heat issues.

[Grounded63]

Originally Posted by Chaparralman1974

Maybe I should just say screw the blasting and try to just DA the paint enough to recoat it???

Try to find out who is doing media blasting for restorations and or exotics, in your area. ( Not the guy that only sand blasts farm equipment. Or is primary a powder coater. )

[LS short box]

One other note.
Check with local car clubs in regards to media/sand blasting.

[Chaparralman1974]

I think that I am just going to have the inside and underside blasted. I will use a DA/SCT combo on the sides. I will likely just replace the wood anyway with oak.

Thanks for the help and ideas everyone!


Clay