Blasting Media for Coupe Body

[BLB27]

I have talked to a body shop about blast cleaning my 1927 coupe. He is well aware of the potential problems associated with blasting cleaning. I am going take the trunk lid, one of the splash panels, and maybe a fender to him. He will use both walnut chip and sharp glass media, with reduced pressure, as trials. He may also try a combination of both.

I would appreciate comments on this plan. If any of you have had experience with either of these media, that would be helpful.

[speedytinc]

I wouldnt take sheet metal to a guy that has not blasted before. You dont want to be the first guinea pig.

[John kuehn]

I have a neighbor who uses a local soda blasting company to come out to blast and strip down the bodies of the classics era cars he restores. I have never used it but it is getting to be a popular method of stripping down car bodies. It’s not supposed to be as abrasive as sand or even walnut shells but that probably depends on how rusted a body might be.
A lot depends on how much pressure is used I would suppose also to keep from scaring up the metal or warping it. Most media has its good points and not so good as with any methods used.
There may be some companies in your area that will come out and do it if you have a place to do it. Those folks do this for a living so they may can be help in making a decision.
Do a search to see if there is.

[TXGOAT2]

It might be a good idea to have an experienced paint person look at the car as-is. It may not need to be stripped to bare metal. It might not even be a good idea.

[jiminbartow]

You asked so I’m gonna tell you. Don’t do it. Compound that body and try to save the original factory applied paint. Golden rule of antique car restoration. You never sandblast body panels! The high pressure can distort, deform and destroy sheet metal. Jim Patrick

[ThreePedalTapDancer]

https://ttdustlessblasting.webstarts.com/

Dustless blasting at your property. Uses water mixed with sand, no heat or warping. The liquid has rust prevention too.

[Allan]

Because of their compound curves, blasting the fenders should be no problem. Howewever, the flatter the panel and the larger the panel, the more likely it will be distorted if the blaster is not familiar with the process. So, the splash panels may be OK, the deck lid even more suspect to damage. If it has to be stripped bare, would do the job myself, using chemical paint removers. That's about the gentlest way to do it.

Hope this helps,
Allan from down under.

[TXGOAT2]

Sandblasting, if needed, is for castings and forgings and heavy gauge pressed steel items. Media blasting, such as walnut shells or soda, is much less likely to do damage. Original paint that is adhering well to the metal may be best left alone. You don't want to peen sheetmetal, unless you want to change its contour. Proceed with caution.

[TRDxB2]

I have talked to a body shop about blast cleaning my 1927 coupe. He is well aware of the potential problems associated with blasting cleaning. I am going take the trunk lid, one of the splash panels, and maybe a fender to him. He will use both walnut chip and sharp glass media, with reduced pressure, as trials. He may also try a combination of both.

I would appreciate comments on this plan. If any of you have had experience with either of these media, that would be helpful.

If its the original paint that has been bonded to the metal for the last 95 years why remove it all? W ill you get a better bond than that? The word on the street to remove paint off a car is Soda Blasting as shown in the picture above. Sure he knows that if the blasting method heats up the metal it will distort it. If you insist, start with the part least likely to distort.

[TXGOAT2]

Particle blasting can distort light gauge sheet metal in at least 2 ways: 1. Localized heat buildup. 2. "shot-peening" effect, where tiny impact pits are formed in the metal surface, causing the metal to warp. 3. Due to effect # 2, the original surface texture of the metal, if still present, is altered.

[TXGOAT2]

Questions: What gauge are Model T bodies? What gauge are Model T fenders? What gauge are Model T running boards? Are floor pans, if any, heavier gauge than body sheet metal?

[PDGx]

https://ttdustlessblasting.webstarts.com/

Dustless blasting at your property. Uses water mixed with sand, no heat or warping. The liquid has rust prevention too.

DD10C58F-0E0C-4942-8616-12A3BCFE499D.jpeg

Dustless blasting is definitely the way to go. Used it, and would do it again. Preservative lasts for a couple months if you keep it dry. Then use a self etching primer to seal the bare metal.

If you just dry blast it, you will be hurrying to get it primed before they humidity starts rusting it immediately.

[Allan]

There is one very good reason to remove all old paint before repainting any parts. Today's paints can be incompatible with old style finishes. If they don't react instantly they may well do so down the track a little. I would be hesitant to apply any finish over a substrate of which I had no idea of compatibility. That said, household type enamels will go over most things.

Allan from down under.

[TXGOAT2]

I believe '26-'27 T bodies were finished in pyroxylin (sp) finish which may be the same as Dupont Duco. I don't know if you can obtain that stuff anymore.

[TXGOAT2]

Pyroxylin is Duco. Duco was very widely used in the auto industry for decades. A good restoration shop might be able to advise as to availability and compatibility.

[Allan]

In another post, it was reported that spray cans of the same brand bought from two different sources were incompatible with each other! Perhaps this illustrates best my reluctance to mix unknown paints/finishes. I am betting today's automotive paint suppliers will not guarantee results if you use others base coats/primers/fillers.

Allan from down under.