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I don't know much in this field, But"media blasting" needs to be more specific on which medium to use. Sand and sodium bicarbonate are only 2 of the many choices. Some smarter person will take it from here

i had my frame soda blasted and there was only some light rust stains left. nothing major. this was done by a professional outfit and not a home kit btw.

i have seen regular sand/media blasting of parts and i can tell you it will strip rust off like no other. i use Steel Grit in my cabinet and it will rip the rust right off.

i plan ot having a proffessional outfit do the car though. not gonna make that kinda mess in my driveway.

Hank

I just finished having my 51 200 painted. It had three layers of paint on it, so I took it to a local stripping outfit. (see the blog on this project for more details). He used crushed glass - it took off all of the paint and most of the bondo. It would have taken it all off, but my painter wanted to see where the bad spots were. The car had a rusty replacement hood I put on since the original hood was badly dented. The glass took all of the rust off, without any deforming of the metal or damaging the glass. It was also much easier to clean out the car than one that was sandblasted. It cost me $700 to have it done, but it was worth every penny. I have used a friend's sandblaster on small parts and it took me almost as long to do four wheels and a dash that it did the stripper to do the entire car using the crushed glass.

I think the choice of media is the key and sand or some of the hard grits might not be the best choice on many of the older or more delicate metal items.

I was told that while sand will quickly remove almost everything (except undercoat), it was not a good idea for the amateur on sheet metal because it is so hard. Unless the operator really knows his business and has the pressure and speed action just right, it's like a gazillion tiny hammers. If concentrated in a spot a fraction too long, it can warp a panel in seconds.

In your case with the treadle vac I'd stick with the soda -- or maybe ground walnut shells. Unless it was another soft media, I'd be concerned that the can or shell metal might be thin enough to distort slightly for the piston to slide smoothly. You might also roughen a surface that needs to stay smooth or someplace that needs to seal well..

For parts derusting I like glass bead, that is another name for "crushed glass". Very effective. As Howard has stated, you have to be very careful about body panels, sand and glass bead can work-peen a panel and there is very little you can do with it after that has happened. THe crushed walnut and plastic media are great for body stripping as they do not have the ability to work-peen the steel.
In the shop I worked in we pput dang near every part of the car through the glass bead cabinet at one time or another.

I do reloading too, and have thrown chrome window crank handles, chrome ashtrays and just about anything that will fit into the tumbler and left them overnight....even longer..... I use walnut shells and have been very pleased with the outcome of this form of chrome cleaning and shining...I experimented with cleaning Packard glass lenses and doesn't hurt the glass and cleans the glass and water deposits right off. Ditto with a complete outside rearview mirror. However, some testing should be done on your own to figure what's suitable and not. (disclaimer). Hope this helps.


Edit: I do nuts and bolts too, however, be sure all the tumbling media gets removed from every slot, screw hole and blind orifice. Lord help you if you decide to clean carburetor parts in there. Hope this helps too.


Steve.......

I glass beaded everything I could, and it came out great. There also it's all about the "angle of attack" with the media blaster gun. You want to keep the gun moving and be blasting at a angle to the part as opposed to straight on.

Many of the larger commercial media blaster around here have moved completely away from sand because of the silica respiration hazards.

Quote:

Never use silica quartz sand. For 'sand' blasting, use aluminum oxide. Much safer, though you still need to wear a hood.

Remember, Safety: It's in the top five

Cheers,

Tom