[NewParOwner]

Hey everybody, It's been a while since I've posted anything on here but I have been reading ALOT of posts.
I have a question regarding the body of my '73 Charger. I purchased a '73 Charger back in May of this year. This is going to be COMPLETE rebuild and I have a fair amount of experience in the "mechanics" of autos. My issue is the body and how to handle the restore process of surface rust on the panels, like the roof the hood and other large panel areas.
The car had a vinyl top, I am not sure how long it has been off but I want to convert to painted surface. Naturally, there is a signifcant amount of surface rust where the top was.
I guess my question is.......Should I Soda Blast (which with my experience doen't do much for rust) or use another media? OR should I not blast the body at all?
I know sandblasting causes alot of heat and can (if not careful) distort the larger panel BUT with extreme care and the use of the "home" style sipon blasters.........would this not be a better choice for the rust removal to get to clean metal?
What are the other "BETTER" choices?

I am just now getting started with the whole process and any helpful insight from the more experienced body people outhere would be greatly appreciated.

I just don't want to screw up on the top of this car and I mainly need a remedy to stop the rust from getting worse, it is sitting outside until my new garage is completed and can get it out of the weather........the rest of the body is in pretty good shape.

Thanks in advance from...NewParOwner

 

[Bob Lincoln]

Not an expert on this, but I have heard that soda blasting is better as far as reduced pitting of the metal. However, if it's not cleaned off thoroughly, it may cause slight embrittlement. For benign surface treatment, I've heard that walnut shells are a great media.

 

[dana44]

Used to have a professional sized sand blasting setup when I was younger and did a lot of blasting. Fine sand works the best, used several times if far superior to fresh sand, so use the finest grain you can get. I never had a problem with warping panels, blast from 15-18inches away and no damage occurs. I recently had a conversation with a friend that did use soda blasting the first time on a 69 Road Runner and it was a mess and did little to nothing to rust, so that kind of defeats the purpose of blasting rusty panels. Dipping has problems that if the seams aren't cleaned out enough or the stuff not neutralized properly, you have worse problems than you did before, so only use it on removed panels, not the whole body, things like fenders and hoods can be flushed and easily dried outside in the sun without the chemicals causing future rust issues with even the slightest amount of humidity, and you can get paint and sealer in the cracks to prevent future problems. One issue with sandblasting is the sand gets into everything, so if you are going to be on a rotisserie in the future, do a dozen quarter turns and vacuum the sand up a lot. Use a metal prep and rust converter and then epoxy primer shortly thereafter. If you aren't going to be primering or doing body work within 24 hours of using epoxy primer (not primer sealer), a quick cut with 320 grit sandpaper before anything being sprayed on it otherwise it won't stick and the paint will peel off.

 

[trs11758]

you can regulate the air pressure or stand further back when sand blasting..anything with rust/bondo/adhesives will be gone, there will always be body prep afterwards, i agree with using a fine sand for the body, i have used a coarse grit for undercoatings/chassis/and suspension due to the metal being thicker, at a slightly higher pressire and then used the lighter grit for anything else left behind. a shop vac works well..
Note: i did use it outside to avoid a huge cleanup inside the garage..and made a small wood frame with a tarp for containment, safety glasses,a painters tyvek suit (sand goes everywhere, and i mean everywhere!,lol) and a mask for the dust and leather gloves are needed..
you cannot beat the speed it takes to get everything done (especially into those small detail areas)and it is the least expensive option

 

[tazdevil]

I had the Demon body, underside and complete body sand blasted by a monument shop. I learned that sand blasting does not remove things like undercoating, and sometimes glue residue. It was a real eye opener to find what had been "bondoed over", and certainly was worth the $400.00 to have it done. The car was metal prepped and POR15 applied to some small rust areas, to good success. After rust repair, the car was shot with epoxy primer, and the car's finish looks like glass.

 

[dana44]

Definitely. Bondo takes a bit to remove, not worth the effort most of the time, if it can be blasted and not come off, it isn't going to. Rubber glues, undercoating, same thing, they are too soft and sand bounces off them. Blasting chrome is pretty cool, it turns yellow/orange and is cool to look at (until it's gone). As far as body blasting goes, rotisserie spinning the body and lots of vacuuming helps get the sand out. Last time I drove the Nash, which was blasted about ten years before I really got her street legal, I was always getting sand in my eyes.

 

[AC TC]

soda wont make it, sand will but what a mess and you have a problem with warping if not done careful.
Actually i belive that a DA sander would do it and some elbow grease...