Soda blasting body panels?

[wangdango]

I would like to get the bodywork stripped on my BJ8, panels are off the car. We have a local company that does soda blasting, and I really do not want to sand or use stripper to remove the paint. Have heard that the residue left after soda blasting is very hard to remove and therefore primer does not stick. Anyone with experience want to chime in?
Thanks
Ed

 

[Patrick67BJ8]

I would like to get the bodywork stripped on my BJ8, panels are off the car. We have a local company that does soda blasting, and I really do not want to sand or use stripper to remove the paint. Have heard that the residue left after soda blasting is very hard to remove and therefore primer does not stick. Anyone with experience want to chime in?
Thanks
Ed

I just had some panels doen: Hoods, Trunk Lid, Drain Channel. There is a residue and it can be removed with regular soap and water and scrub brush. Once removed on STEEL panels/pieces you should apply a think coat of WD-40 if they're going to be sitting for a while otherwise, bare metal will quickly start to rust.

I have heard of people using a vinegar/water solution, but my "soda man" says that warm soapy water is just as good.

 

[BigGreen]

Acids or bases, both will do ...

https://en.wikipedia.org/wiki/Sodium_bicarbonate#Neutralization_of_acids_and_bases

Hans

 

[Frameman]

When soda blasting outer body panels you must lightly re sand blast the aluminum. If you fail to do so you will never get paint to stick to these panels. We had aluminum panels soda blasted and washed them down with soap, water and vinegar and this does not work on aluminum. This lessen costs us $10000.00 to re-spray the car because the paint was coming off in sheets. The panels must be lightly sandblasted. The panels will not be destroyed if you have a good sandblaster. We will never chemically strip.
Martin Jansen

 

[JP_Furble]

My Bugeye was soda blasted during restoration in 2004 at the suggestion of my body man. I don't know how (or if) he cleaned the residue off prior to painting but after only a year or so I noticed small blisters forming in the paint. I would suggest not soda blasting unless you have some reasurances about the clean-up process afterwards.

JPF

 

[57_BN4]

Martin- thank you for sharing your hard earned knowledge about soda blasting aluminum.

I have done the majority of stripping with methylene chloride and am planning on giving the white aluminum oxide fluff in the seams a light garnet blast before painting, perhaps I'll get the entire surface of the shrouds roughened up too now.

Andy.

 

[Bob_Spidell]

Martin,

Do you attribute the bad results to the Al surface not being abraded sufficiently by the soda, or to a possible chemical reaction? Was the Al sanded prior to application of primer?

I'm learning how to paint and all insights and tips are appreciated. We removed the paint on our BN2's shrouds with chemical stripper--the kind that comes in a gallon can you can get at Home Depot (methylene chloride-based)--then hand sanded prior to applying primer. So far, so good.

Thanks,
Bob

 

[dancrim]

I hand sanded my BJ8 shrouds to bare metal, washed them down with dish Det.
and hot water. Then treated them with "Ospho", a chemical deruster and
etcher that you can find at some hardware stores. I guess naval gelly would work. The secret to these products is to apply very sparingly. The problem with aluminum is that it oxidizes so fast and hen tpaint won't stick. My paint is 3 years old and looks like the day I finished it. Some guys tout vinigar but I never had any luck with it.

 

[Marvin Gruber]

Mine was blasted, I washed it down with muratic acid from Lowes, then soap and water. Epoxy primered before top coat. That was years ago. Paint looks new.

Marv

 

[Bob_Spidell]

Marv,

What did you blast with?

 

[Frameman]

This happened to us in 1996. I think it was chemical reaction yet when we tried the vinegar on the panel there was no reaction to the soda. We had two paint reps from PPG and they could not give give us a clear answer to the problem.
The process we use now is soda blast then sand blast than sand by hand back at the shop then use washed down solvents and procedures prior to paint. New metal repairs will be etched/ sanded to ensure no future paint problems.
We have not had any problems since using this process.
The environment plays a very important role in the paint finish. I notice the cars in Florida have a very deep shiny paint that I don't see in the north.
Martin

 

[Patrick67BJ8]

My car's chaassis and body, with the exception of the Boot and Bonnet, was sand blasted and all steel panels were wiped down with WD-40. The shrouds were sand-blasted and left untreated. I just had the Boot & Bonnet soda-blasted and washed them down with soap & water as recommended by the company doing the soda-blasting. Both of those panels are pretty smooth compared to the other steel sand-blasted panels.

It appears on the topic is that there's a lot of variables to treating the panels after they are soda-blasted. I hope we reach some sort of "best method" soon because my car's going to the paint shop in a week or so.
Thanks!

 

[Bob_Spidell]

Interesting. The vinegar--which contains acetic acid--could have reacted with the aluminum forming some variation of aluminum acetate. Whether that would hurt paint adhesion or not I can't say.