I am getting ready to strip the paint off of my hood and some other panels. I have sandblasted the under carriage and firewall with silica sand. I want to use baking soda on the hood and fenders and quarters. Has any body used this and where do you get huge amounts of baking soda?

Soda blasting is not to be done with standard equipment. Check into plastic media for your project.

Some of this media leaves for a better word (oil) on he surface. You have to metal prep all metal to be safe. Thess special media's don't produce what you expect. Talk to some shops that do this for a living.

I'm lucky enough to have a media blasting shop locally that does this for me. He doesn't use soda blasting that I know of but his rule is this:

Paint removal - Plasic Media
Rust removal - Sand (Plastic won't take off rust)

I've had inner fenders, header panel, and grill supports done. Plastic does great getting the paint and underbody coating without pitting the metal graemlins/thumbsup.gif .

Glass bead will also take rust off with out too much heat. Sand produces tons of heat, as in you can't touch it hot, which causes warping problems.

Steve

Word of caution:
Depending on the type of soda it can and WILL lead to adhesion problems later down the road if you fail to remove the residue left behind by the soda.
A simply sanding will not remove it.
As for what will I know no idea, but I would look into different methods of paint removal other then soda blasting.
if all you want is to remove paint then media blast with plastic. Also if you have slight rust you can mix in glass beads to remove light scale.

Ive read many articles about soda blasting and it seems right now to be a method that needs some tweaking...Eric

Silica sand should not be used for blasting unless you use the same breathing precausions as when you spray urathanes. Silica poses great respitory risks.

The biggest issue is you can't use any form of etch primer over it. The soda left in the pores of the metal nuetralizes the acid in the primer!!

Then I was working for S-W one of my fellow reps had a customer with a '55 Chevy that was soda blasted. He recommended that the guy etch prime that bare metal and he would have a great base. Well, after this car was done, the paint, primer, the whole shabang came off in sheets! :eek: Right down to metal like the darn metal had been greased before primeing or something.

They stripped the car again and it did it again! After the second time they ran it up the flag pole with Sherwin and found out the problem. Needless to say the reps butt was in the ringer with that shop.

So in the end what was done to correct the adhesion problem on the 55? A good friend of mine owns a media blasting business and uses soda for most everything and nobody I know of has had any problems with adhesion after he does the blasting. My Son's Nova tub will be at his shop soon for soda blasting with silica on the firewall and underside. If there's a certain proceedure after the soda blast I sure would like to know. I'll also ask the Dave at the blast shop and see what he recomends, I do know he uses mostly epoxy primers. Bob

Bob, to tell you the truth, I don't know what they did. I would think a metal conditioner and then epoxy would have taken care of it. But I don't know what the final repair was.

I talked with the blast shop today and they recomend a water wash with a scotchbrite pad for prep before self ecthing primer. They also said some people use a vinegar and water solution for the tough to get at areas, nooks and crannies to remove the soda. This doesn't sound good to me, water and bare metal don't mix well in my opinion especially in the humidity of summer. I dropped off the decklid today for a test, if all works well I'll bring the tub over. If I'm not happy with the soda results then we may strip the exterior surfaces ouselves and have the floors, firewall and jambs sandblasted with regular silica. Water washing one panel after the soda blast while fighting flash rusting before primer will be a job in itself let alone an entire tub. I'll report the outcome. Bob