The Stovebolt Site Forums The Shop Area Paint and Body Shop Blast or No Blast?

Hello all. I have a 59 Apache panel that I bought out of a field. It has quite a bit of rust, inside and out.

The body resto would be a lot easier if could media blast it. However, I'm wondering if this would create as much work as it eliminates. I don't know much about the process, but I assume that any weak areas of steel will be blasted away.

Here are a coupla questions:

How does one guesstimate how much steel gets blasted away?

Which media are less abrasive and won't take away as much steel?

Does the experience and capability of the shop matter or is blasting just blasting?

What things should I consider for the blast-no blast decision?

Thanks from a newb.

Find someone who specializes in restoration blasting, and not industrial blasting. I would caution against using sand, as many types of sand contain caustic salts that, when the metal surface is broken, will start the rust process again, regardless of how clean the panel looks. There are plenty of other blast medias available at a similar cost that will not produce the salt damage issues.

I'd suggest reading up on some of Porchdog's posts on Trifive dot com, he does it for a living and does it well. He also suggests no more pressure at the machine than 35-40 lbs, and hold the nozzle at a 45 degree angle to the panel. Any access holes should be blocked off when blasting insides of door panels, etc, as inadvertant blasting that contacts the back sides of exterior panels can cause stretching/warping. It doesn't take long for someone who doesn't know what they are doing to ruin sheet metal.

may also look into dry ice and soda blasting... It's pretty affordable to just drop it off and let them do the magic! especially for just a single part already dismantled.

be very leery of soda blasting, most paint manufacturers now will not honor their warranties for product failure when used on pieces that have been soda blasted

Bill

Interesting! I'm not in the loop on that, good to know!

Thanks, fellas.

MP&C, Mr Porchdog's posts are a font of info!

And I suggest reading up on some of MP&C's posts here as well as the links he puts up for other sites of the work he does. I find them to be very informed with great visual support and easy to follow

Rick, thanks for the kind words. I've just been trying to help guys get over the learning curve I had when I started. There is quite a bit of reference material out there today, much moreso than even ten years ago.

My experience is if his truck is rusty as it sounds he will need sand. I've tried plastic and soda. It just plain won't get the rusty stuff clean.
I buy my sand at the local concrete mixing place for $.25 per 50lb bag. I use Fine but they have Extra fine and medium. It is "sized" and works very well.... and its also the choice of a couple professional's I know that also do soda and other stuff. They all agree soda and plastic is good for getting off paint but not for RUST....... just my .02

I'll agree that soda and plastic are not agressive enough to remove rust issues, but sand introduces salts into the mix, not a good combination pounding against bare steel. One of the members on Chevy Talk was having issues with spots of rust having formed under his epoxy paint (found in subsequent body work) and come to find out, he blasted with sand.

Here is a link to the threads by Porchdog on sandblasting, he makes some recommendations for media that is just as economical as the sand you purchased without having the ill-effects of salts on your bare steel.

Porchdog's sandblast posts

The Porchdog link goes toTriFive.com forum: "Sorry - no matches. Please try some different terms."

I just updated/edited the link in my last post, they must have a time limit on the search function and thus loses the link.

If it loses the link again, go to trifive dot com, then the search tab, then go to advanced search, and then type in sand blast as key word, and porchdog as user name.

My truck goes to the media blaster/metal cleaner next week. I am taking frame, cab, bed side panels (others get replaced) doors, hood, and rear fenders (I did the rest of the panels). The company I found does many classic cars each year and knows what they are doing ( they did Lance Armstrong's ride for Overhaulin'). I was told they would use plastic media to remove dirt, undercoating and old paint, etc. Then they would use aluminum oxide on the rust areas. So, mostly aluminum oxide. The key things to avoid metal damage is distance from metal and air pressure control amoung others.

I was talking to a buddy yesterday who has 3 cars being restored at his shop. 2 were blasted, one was dipped. He said the dipped vehicle is much easier to work with. It welds better and collects less rust. No need for surface prep before welding. (I guess it gets a phosphate coating after the dip. Most of what he said was over my head.)Both of the cars that were blasted had some distortion in the metal. None with the dipper.

He strongly urged my to go with dipping, even though the cost is considerably higher.

Dipping scares me as the chemical gets in seems and I would be afraid the residue would attack the metal over time or leach out and ruin the paint. Media blasting is inert in my opinion. Yes, you have to clean the metal before prime/paint, but I cannot see how it would affect welding in any way shape or form. To each his own.