I'm familiar with soda blasting a Budd car which leaves a nice polished appearance. Has anyone done glass bead blasting and does it give the same results?

Also, the roof was once painted black like so many other cars and it has weathered to almost nothing. I'm leery of blasting the roof and causing leaks. Can this be done or am I worrying about nothing?

Background: We have a Budd diner that had the window band painted many, many moons ago. The paint is badly weathered and we'd like it removed without damaging the surface of the metal as well as brightening up the car like you get with soda.

Any thoughts or tips on this?

Thanks.

There is also the option of dry-ice blasting if there is an issue with media embedding into the surface or causing other damage.

Dry ice definitely is a good option. But we're limited in local blasting companies with mobile units. We have a few local soda blasters and another outfit suggested glass bead. However, I think the bead blasting is not going to give the same polished look that soda will though I don't know for sure. A matt finish car ain't what we want.

Glass Beading will give you a satin finish, not likely what you want.

Soda blasting, with possibly walnut or pecan shell (or some plastic media) would be my suggestions. My softest touch using glass beads on stainless sheet metal always left a dullness that I did not care for. As one of my old bosses put it back when our outfit was still doing in-house metal finishing, glass beading is like hitting something with a very tiny ball-pein hammer; you can hit it hard or you can hit it soft, but you're still hitting it with a ball-pein hammer.

The negative I found with nut shells and plastic media was that it took a gargantuan amount of time and air to get through some paint and corrosion products. In some cases, we'd resort to that old standby of the desperate, the high pressure washer. We had an "in" with a high pressure washer manufacturer close by, with access to some dandies that would take paint off as a general rule.* Then we'd use the walnut shells.


*When I was between semesters in college, I worked in a (different) factory that made pressure washers. One of the prototypes they made used a Cat engine to power an enormous pump, and that thing would remove paint from metal like nobody's business. It could also cut through concrete... which back in those days was a rather novel thing to see. Roughly the size of a VW Beetle, the thing howled like a banshee when running, and management was extraordinarily careful to keep anyone from getting injured or killed by it.

I don't get the love affair with glass beads. A little research says that blast media exits the nozzle at 300-325 MPH at 80psi. After the impact is it a glass bead or fine sand?

As I understand it, the point of glass-bead blasting is that it is a once-through process, with the impact serving to 'forge' the surface rather than cut or abrade it. Think of it as a kind of disposable shot-peening.

Yes, the little glass beads are likely shivered after impact, and thereafter they'd behave more like grit-blasting, with many 'conchoidal' edges likely.

I would indeed be leery of anyone advising to re-use recovered glass-bead media for further 'glass-bead blasting'...

Thanks guys. That confirms my suspicions on the bead blasting.

On to the next questions: If we soda blast the roof, are we gonna risk having leaks when done? We don't have any leaks now. Or, should we just repaint it?

Another plus to dry ice blasting is that there is no residue to get into journal boxes, on drying paint, or in one's eyes. The CO2 just goes into the air to be utilized by plants. Works like a charm IMHO.

Hello My Friends
I would be very careful blasting flat metal with glass bead as it will disturb the surface tension in the metal and cause distortion, warpage. Walnut shell will only remove the paint and mild corrosion. Although walnut shell is a much slower process it is very gentle and won't disturb the metal.
Jack

Wash stainless steel with Sunlight dish soap! Buy it by the drum/pail.
Worked for CPR for decades.

Just use paint stripper on the roof (if you can find real paint stripper any more). Then acid wash the car. Nothing works better that I have found. I'm not aware of any media blasting that will "polish" a stainless-steel surface.

Soda will remove the paint and yes, it actually does bring out the luster of the stainless steel. I've worked with a few private owners of Budd cars that have soda blasted them and the results looked amazing. Bright and shiny like you did the car with buffing compound and a buffing wheel. Never tried acid washing or know someone who did.

Stripper with soft plastic scrapers would probably work on the window band paint but where the paint that was left is removed it will leave blotchy marks that you need to deal with. Soda will remove the paint and buff the car in one shot. It also won't warp the metal like more aggressive media does. I wouldn't attempt stripper on the highly corrugated roof. Way too much mess.

Jack B - great to see you posting here now! You are the legendary wizard fabricator from the model Live Steam Railroading Chaski forum, are you not? For those that don't know him, he's amazing...

Any comments on blasting the roof and creating leaks?