scrappie

I want to clean the body shell I have of all rust before metal work over the winter. I have it on a rotisserie right now so it can be spun and accessed pretty easily.
I know a guy who will media blast everything in and out for prob around 400+/-. He did my frame and some suspension parts and did a decent job. The trouble is, I would have to rent a flat bed trailer that tilts to roll this on and secure it really well because its kind of top heavy and bring it to him about 25 miles away then leave it on trailer and have him blast it then pick up and drive back.
OR I could have a guy who has a mobile dustless system come to me for about 700. The only thing with that is the water and flash rusting that concerns me. He has an additive to put in tank to prevent flash rusting but Ive never used that system before.
What do you guys think?

Charlie Jones

Make sure your " guy " is well versed in blasting sheetmetal . Ask him for references of people that he's done sheetmetal for .
It's very easy to warp sheetmetal with overaggressive sand blasting . ( Ask me how I know , I completely ruined a '37 Pontiac hood before I learned . )

Frame and suspension parts are easy to sandblast . They are thick enough that it's almost impossible to warp them . Not so with sheetmetal .
This takes skill .

TripDeuces

I had a dustless blasting guy do mine without the water and it came out great. The pressure was reduced and he used a very fine sand. Almost like sandbox stuff.

oddball

Either way will work fine - as noted, the important part is operator experience.
Keep track of what material is used. If it's soda, then the painter needs to know because specific steps need to be taken to neutralize the residue before anything is laid down.
The dustless blasting companies are marketing like crazy, so it must be good!

joe_padavano

And isn't that just conventional media blasting???

I've done my own media blasting of sheet metal using a pressure pot with no issues. I use crushed glass media and dial back the pressure. I also keep the stream at an angle to the sheet metal. I've also made my own wet blasting setup using a garden sprayer nozzle strapped to the side of the blast nozzle. Kept the dust down but didn't really make a difference in performance.

TripDeuces

Sure is but without the worry of water on your blasted metal. The most expensive part of that whole Dustless process is the anti-rust compound added to the mix, it's expensive. After talking to the blaster he said he could do just as well with plain sand without the added hassle. I took his word and expertise and I couldn't be happier.

Cleaning the body off and getting epoxy on it as soon as possible was my goal. Rust acts fast so have a plan in place to protect your project.

oddball

Heh, I sanded down my body at home (lots and lots of DA disks) and just used a phosphate wash (Eastwood Fast Etch, Eastwood After Blash, Por15 Metal Prep, whatever). Left the body in bare metal for ....... 6 years? Even drove it that way quite a bit. Some surface rust would pop up, but sanded right off and just re-etched.

Flash rust is a PITA when washing an engine block. But initial body work on a shell? Nah, just have to do a quick cleanup right before laying down the first primer, which should be done regardless.

scrappie

Thanks for the responses.
I spoke to Dustless guy about no water in system and he is unable to run his equipment without water. I think Im gonna give it a shot anyway and use the additive. I will let you guys know how it comes out.

HammerMass

Scrappie - I can recommend the Dustless Blasting as it will give a very fine finish to the metal and the water helps to keep heat from building up in the body panels. Just be prepared for a MAJOR mess in your yard as this stuff goes everywhere. I'd have a large tarp laid down under the rotisserie to collect as much of the sand as possible and I also highly recommend sending your wife away for a "well earned" weekend and having it done then. Have her take your son also so he can't leverage it against you. Good Luck!

HM

scrappie

Good advice, I just may do that.