DIY sand blasters?

[Matt S.]

I have never ever done, seen, or known anyone who has sandblasted ANYTHING. So forgive my ignorance. I did some basic searching around and couldnt really figure anything out:looser:

I am currently stripping a heep down to the bare bones. Glass, doors, bed, every bolt, etc. I want to somehow take all the undercoating, paint, and crap off without going at it with a wire wheel. Is sand blasting something i should really be considering? Will sandblasting the cab make it difficult to paint? What do I need to do it myself? Or is paying the way to go?

 

[RichP]

I have had professional body people tell me that sandblasting is not the best way to go, chemical strippers work much better. One did tell me that if I do blast don't do it in an area where I want good paint and a good finish.
That said I would for sure use it on a frame, axles and really nasty areas which are generally areas you aren't really looking for a good finish anyway...

 

[8Mud]

It has it's good points and bad points. A good point is the primer will adhere really well. The bad point is that abrasives get into the cracks, crevices and traps between sheet metal layers and is a pain to get back out. A simple blow it all out with compressed air, isn't likely to move all the abrasive out of the traps.
The abrasive is fairly expensive, if you use sand you are likely messing with the next best thing to asbestos or coal dust for messing up your lungs. It takes a rather large compressor and someway to recover most of the abrasive, it is too expensive to use only once. Some kind of fine filter mask, full face shield, thick gloves and heavy clothes are a must. Even a small sand blaster will take your skin off jiffy quick.
A hand held blaster with a quart sized bottle will do well, but not all that quick. Takes a lot of refills.
You need a good dryer on your compressor, if the abrasive gets moist it will plug up your blaster pretty quick. It also takes a rather large compressor, you will likely be waiting a lot for the tank to refill.
I only use my sand blaster on stuff that is almost impossible to sand. The rest of the time I use a high RPM wire wheel on my jumbo angle grinder. You really need some serious protective clothing to use a wire wheel with an angle grinder. I once pulled some wires out of my cheek with a pair of pliers and they came out hard. Kind of like Cactus thorns.
I learned early to keep the sand blaster away from the house, some abrasive flies 30-60 feet or more and gets into everything.

 

[Stumpalump]

I had a small home use sandblaster. Have you ever seen the size of the compressors and equipment they use for bridges? You will soon learn why. These things use a ton of air non-stop. With the home units you can blast tiny spots like door dings OK but anything else takes hours if your air compresser holds up. The sand will kill your lungs and is not legal anymore to add more expense. If you already own a huge compressor then make sure you get a pressure unit. It puts pressure on the blasting media. The siphone units are worthless. I can't think of the name of the tool but an air tool is available that uses a bunch of nails or wires that vibrate and eat up rust real well. I think it's called a scaller.

 

[Matt S.]

Well.. i guess it is looking like there are to many con's to sandblasting. Anyother trick ideas to clean an entire rig of paint, grime, undercoating?

 

[8Mud]

I use a wood chisel (works better than a puddy knife) a good solvent to remove the residue and sand paper. 3M abrasive discs are good also, if you can find them on sale.
Take the loose stuff off anyway you can. Smooth out the rough spots with 220 grit sandpaper (wet and dry works best) and primer it. It doesn't have to be clean metal. If the base coat (paint or primer) comes off hard, it is likely on there good and as good a base as anything else. A good primer is the key to having it last.
I have a whole selection of rotary sanders, wire wheels, cone wire wheels, 3M abrasive discs and whatnot.

 

[GSequoia]

Well.. i guess it is looking like there are to many con's to sandblasting. Anyother trick ideas to clean an entire rig of paint, grime, undercoating?

I'd sandblast the underbody without much reservations since you don't worry about a good finish there afterwards.

 

[RichP]

A growler works well, thats like a big low speed angle grinder, I used one in the auto body course I took at the local vo tech a few years ago. It has a rubber backing disc that you stick discs to. Two of us did a VW minibus in about 3 hours one nite, well, mostly, the nooks and crannies took a bit longer.

 

[Matt S.]

I'd sandblast the underbody without much reservations since you don't worry about a good finish there afterwards.

But now thinking about it, that sand will get EVERY where. Including inside the frame. I dont want to have 10 lbs of sand hiding! I think a good steam clean will solve my grime, then just wire wheel followed by a grider in spots to prep for welds.

 

[8Mud]

I'd sandblast the underbody without much reservations since you don't worry about a good finish there afterwards.

Trying to get all the sand out of the frame rails will drive you nuts. if I ever do it again, I'll plug all the holes in the frame. No matter how much air I blew into the frame rails, sand still came out. I tried plastic hose extensions on my air pistol, a pressure cleaner and then more air and still had sand in there.
I recoated the inside of the frame rails, figured I might as well, sand and all.
I'm still finding abrasive in odd places.

 

[jforse]

Talk to some local bodyshops and ask who in your area does bead blasting. It is similar to sandblasting but a differnet media is used. (think of small rubberized BBs) It won't build up and find its way into small cracks.

 

[Timco]

Soda blasting...finest thing since sliced bread.
Needs to be done by a professional shop...but MUCH better than sand blasting. One of the few media that will eat undercoating, & will readily wash away with water.

 

[motorcityxj]

well to save money on the professional media blasting (not sure what is best for what surface .... for example walnut shells are good for fiberglass since they dont take off as much and dig into the substrate of the fiberglass). I would chemically strip the undercoating. There are strippers for this but i cant remember the name. Simply brush on let set, and get some putty knives and you can scrape off 98% of the undercoating and save $$$ from the pro sand blaster or time yourself.

I think eastwood sells the stripper.

Whats the end goal scrappy? Just a pristine undercarriage ? you doing anything custom here.

 

[Stumpalump]

.99$ Walmart oven cleaner. Get the toxic full smell kind. That stuff will clean and strip off a lot of crud. Use gloves, a dust mask and eye protection when you spray it. I just put the order in on the old ladys Walmart list and allways keep it on hand. The grocery store is 4 dollars a can so get the Walmart cheap stuff it's just as good.

 

[Powerman]

A friend of mine owns a stripping shop. He uses soda. Most of his work is chasis people restore. Strips everything, but undercoating is softer and does not strip as well. That is a big task though. Is it really worth it? You could wire wheel the underside to get off anything loose then dura-coat it. I would think the rest of it could be spotted and roughed up and re primmed. As has been mentioned sand blasting is out. Media blasting is what you are looking at. To have a shop do it though it will be a few hundred dollars and that is if they have no prep to do. It's really a big job. Especially with chem strippers and that will be several hundred too for the good stuff. Not sure your end result would be worth all that. That is certainly your decision though.

 

[rag]

grinder with a wire wheel and several sweaters/gloves/fulface mask has been doing the trick for years. but thats just me; cheap, stubborn and poor

 

[Rev Den]

Put it on...let it sit for about 15 min, brush the paint, undercoat, stickers, etc...off.

Wear gloves....change often...this crap will eat rubber gloves.

Rev

 

[Matt S.]

The end goal is to beable to stick weld most all the sheet metal that is now spot welded together, followed by a very very very extensive frame plating. I am attempting to build a 20 year wheeler/expedition rig. I need to be super anal about this if I want something I a actually happy with.

Has to start clean to finish clean right? Rev, that stuff should work AWESOME on the inside of the cab.

 

[Powerman]

The end goal is to beable to stick weld most all the sheet metal that is now spot welded together, followed by a very very very extensive frame plating. I am attempting to build a 20 year wheeler/expedition rig. I need to be super anal about this if I want something I a actually happy with.

Has to start clean to finish clean right? Rev, that stuff should work AWESOME on the inside of the cab.

Then you should take it to a shop and have it media blasted. Don't know what you have in your area. Look for stripping and powder coating. If you take it to the unibody, they can strip it easy. I know it is always a choice of DIY or pay. If you want to be super anal and get it down to metal for plating, it would be much easier to have it blasted. The friend that has the buisness strips and powder coats chasis and bodies.

Chemical strippers do work, but it isn't magic. They cost and they are not pleasant to work with. You have to stay with it and keep it wet. It can only go where you can wipe. Then you have to clean the stripper and netralize it. The stuff definitly works. It's good for panel work. I would just think the inside of the cab would be a nightmare. I've just seen it done. I'm no expert though. Just my .02

 

[Rev Den]

When I used it on the hood of an old CJ-7, it took that ugly azz eagle and ALL the paint off the hood in no time....bare metal....clean. We did need to brush it on....wipe it off.

We could tell it was eating through the gloves when our fingers began to tingle....that was to late.

Just thought of this....as you are going to tear it all apart, have you thought about dipping it? It will come back clean, all bondo, undercoating, paint etc will be gone.
Rev