blasting questions

[GreaseDog]

Where the best blast media to use to remove paint and plastic body filler from a truck without damaging the metal underneath? I've got a long road ahead of me with my 77 and thought that perhaps blasting it first would be a good start. Of course before blasting the cab, the doors would be removed, and the cab braced so it can't lose it's shape. Also what blast media do you guys recommend for blasting a frame clean? Looks solid, just scaly and nasty.

And where do I find a good affordable blaster?

 

[animal]

I have seen that sand causes too much heat and warps the metal. I have heard that crushed walnut shells take off the paint and filler with out causing as much heat. Also heard of using a "baking soda" type media. Might work well on a frame as well.
I had a craftsman years ago that worked well.

 

[crazy4offroad]

Tractor Supply has Black Beauty, if you take your time you shouldn't warp anything. I have a cheap CH siphon feed blaster that works good. It came with a really thin wall hose though so I changed it out for a piece of 5/8 or 3/4 heater hose. I just fill a bucket full of sand and carry it around with me as I blast. You'll want a respirator, face mask, something with a hood to wear, ear plugs, etc the sand gets everywhere. White sand works good too and as said above really thin areas like front bumper filler panel or grill you would want baking soda but that can get expensive. Black sand is more aggressive but fine white sand isn't too bad.

 

[HotRodPC]

Soda blaseter might take the flaking paint off, but I doubt it'll get the old body filler off. The idea of the soda blasting to my understanding it get junk off the metal, but not harm the metal and to be used as like a finish blast media after you've used something else to get the rough stuff off. That's just my understanding though, so I could be wrong. I know HF sell a cheap soda blaster now, and I've considered getting one just to try out the process.

http://www.harborfreight.com/catalogsearch/result?q=soda+blaster

 

[skysurfer]

http://www.gmsquarebody.com/forum/showthread.php?t=2699

To echo the others, sand for the frame and soda ash for body panels. I don't believe sandblasting creates heat, having recently spent about 50 hours using mine, but sand is too aggressive for thin metal.

I haven't used soda ash myself but I know it requires extremely dry air from the compressor or it will clog. If you don't have multiple units for drying the compressed air it won't work. For example, the air from my 2-stage compressor goes through a fan cooled air-to-air condensor after the first stage, then into a refrigerated cooler after the second stage of compression before entering the storage tank. Exiting the tank it goes through a water trap separator then finally a coalescing filter. It takes all that to remove the entrained moisture on humid days.

I think you'll regret taking on this project. Cleaning that much surface area a tiny bit at a time will take forever. You really need one of those big-ass blasters road crews use to remove lane lines. Have you looked for a business locally to see what they would charge?

 

[animal]

http://www.gmsquarebody.com/forum/showthread.php?t=2699

To echo the others, sand for the frame and soda ash for body panels. I don't believe sandblasting creates heat, having recently spent about 50 hours using mine, but sand is too aggressive for thin metal.

I haven't used soda ash myself but I know it requires extremely dry air from the compressor or it will clog. If you don't have multiple units for drying the compressed air it won't work. For example, the air from my 2-stage compressor goes through a fan cooled air-to-air condensor after the first stage, then into a refrigerated cooler after the second stage of compression before entering the storage tank. Exiting the tank it goes through a water trap separator then finally a coalescing filter. It takes all that to remove the entrained moisture on humid days.

I think you'll regret taking on this project. Cleaning that much surface area a tiny bit at a time will take forever. You really need one of those big-ass blasters road crews use to remove lane lines. Have you looked for a business locally to see what they would charge?

Good point on the time requirements! I do know there is a place in Memphis TN. I think. I have seen them use in on "Trucks" a couple of different times. I bet there is a place like it in your area. As I recall the cost really was not that bad to have it completed by a pro.

 

[GreaseDog]

http://www.gmsquarebody.com/forum/showthread.php?t=2699

I think you'll regret taking on this project. Cleaning that much surface area a tiny bit at a time will take forever. You really need one of those big-ass blasters road crews use to remove lane lines. Have you looked for a business locally to see what they would charge?

that's not the first time I've heard this regarding this project as a whole. I'm taking a truck that has had a plow on it in use for 30 years, and then sat idle for 5 years in the elements...if I told you the body was hashed, I would be making a huge understatement. This was my grandfathers truck, and he taught me to work with my hands, so that it's what I plan to do with his truck, put what he has taught me to use, and restore his truck to better than it was when it rolled off of the showroom floor in 1976.

He and I always talked about getting an older truck for him, and he and I restoring it doing all of the work ourselves. When he passed away in 2003, we hadn't got that chance, and my mom, uncles, and grandmother decided that I should be the owner of his 77. I plan to do them all proud, doing 99% of the work myself.

 

[animal]

GREAT story! Please be sure to post some pics.

 

[GreaseDog]

Oh, this will be the place the resto thread gets posted for sure. Hope you guys can wait a few years to see it come together.

I've sourced a 1987 R20 donor truck for the L05 and all of the associated wiring to convert it to TBI. Ironically enough my donor was my buddy Tyson's grandpa's truck he bought new in 87. More of a resto mod than a restoration. The current 30/350/203 will make way for a350/700/241 or 208 for better drivability. This truck will never see work again.

 

[crazy4offroad]

Your auto-correct needs to be fired, dawg.

 

[GreaseDog]

Mo betta?

 

[crazy4offroad]

Mucho better-o, muchacho!

 

[dirtroadoutlaw]

Bear in mind that the bare metal will rust if not coated with some kind of protecant. A reputable blasting company will offer an iron-phosphate treatment or the like. Play sand will work as long as you sift it and use a LOW cfm. I assume that you don't have a huge, industrial compressor so that shouldn't be a problem. Keep your blast stream moving to keep from overheating any one spot and keep an eye on your compressor to avoid overheating it because you'll kill it. Don't touch the blasted surface with bare hands either because it will cause it to rust almost instantly. You can find iron-phosphate online fairly reasonably. This will phosphatize the surface and offer some degree of protection until you can get a permanent coating on. Blasting can be a little more complicated than simply removing the old coating down to the bare metal substrate. Good luck!

 

[Irishman999]

I hear ya on the whole 99% of work being done by your self on your grampa's truck. If you blast the entire body with a homeowner sandblaster like I was using, YOUR grandkids will be finishing the project.

The smaller of the two sandblasters I used was a low pressure home owners unit that could still easily ruin a quality home owners 80 gallon stand up air compressor. I ran play sand in it without any problems, it starting getting really expensive buying bags of sand so I started re using the sand without any problems. Biggest problem was the blast pattern coming out of the nozzle, It seriously blasted about 1/4 inch at a time, it was agonizing.

Second one I tried was so god damn big we had to use one of those industrial Ingersol Rand compressors you tow behind a pickup truck. Even using the big one took FOREVER, all I was blasting was the inside of my mini trucks bed.

If you want to do all the work yourself and not have to buy a 5 thousand dollar air compressor that can run constantly I suggest this gnarly disk sander Harbor freight sells. This thing stripped years of surface rust with no problem. After that You could use a DA sander, im sure you already know all this ****. Just thought I would share my experience with sandblasters.