Any recommendations for a decent sandblast gun that can do larger grit capable of stripping the wheels and frame? I finally got a new air compressor, but my little blaster with the medium grit quartz sand is barely touching the wheel. I could use some recommendations for a cheap sandblaster (seems like the ones with overhead hoppers are more reliable than the canisters underneath?) and for what type of media would be best for the task.
The new air compressor is a HarborFreight unit -- 29gallon tank, 2HP motor, maintains about 6cfm @90psi. Certainly way better than my previous unit, and this is as big a compressor as I could fit into the available space.
She's a beautiful mess, and I've made her all mine
I have a 26 gallon 2hp compressor from Craftsman... regardless of what their advertisement and spec's say, max output is more like about +4cfm to 5cfm at 60psi to 70psi in mine.
I run it up to 100psi and it's still not enough poop to run my little gravity fed hopper sandblaster gun for more then 10-15 seconds with a full blast.
The gun info says: 7cfm@90psi with a 29 gallon tank is intermittent duty (they aren't kidding).
Mine just completely peters out in 20 seconds or so and I come to a dead stop until the tank recovers.... like two mins of sitting there with my thumb up my rear end while it's electric motor and compressor is roaring away filling the tank.
What a waste of time.
2016 Triumph T120 Bonneville
Far North East Metro Denver Colorado
You need a bigger compressor. Your wasting your time and money on anything smaller than a 60++ gallon air compressor. I've got a 60 gal and even it has a hard time keeping up with air tools being run continuously. Particularly larger ones like 1/2" impacts much less a sand blaster that consumes more air than most tools do. I just bought a new compressor pump to put on mine that's rated at 145 psi with 17.5 CFM @ 40 PSI, 15.2 CFM @ 90 PSI. I wish I could have gotten a bigger one but that's as big as my motor can handle. I haven't installed it yet but that's 4+ cfm's more than the original pump. Didn't somebody say 4-5 cfm's is about all there's is actually putting out? You just can't get anything done with that. Their fine for airing up tires, short blast with an air gun and low pressure painting but other than that ... forget about it. Lol.
As for a good blaster, your compressor won't run a siphon fed unit. Not enough constant cfm's to pull the sand up through the hose. That leaves you gravity fed or pressure fed. Both also use a lot of air just not quite as much as the gravity fed. The better choice between the two is the pressure fed. The cheapest is the gravity fed.
I used a crappy little 20 gallon 2HP Campbell Hausfeld compressor for many years, and blasted tons of stuff. Yes, you have to wait for the unit to catch up when blasting, but it will get the job done, just not quickly.
For doing a frame I suggest you first chemically strip the old paint and then wire wheel off the remaining paint remnants. Use the blaster to finish the job and get around the various brackets and such. Blasting the frame straight out will seem like a lifetime of work, even if you have a large home compressor.
My previous compressor was a 3/4HP with a 7gallon tank, so what I have now is a *huge* improvement over that. As I mentioned above, this was the biggest one I could get for the available space. The gun I have now holds maybe a pint of media. HF listed it as about 1.6CFM, but the reviews and the paperwork that came with it claim it's actually 6CFM... a huge difference. The old compressor wouldn't last long enough to get through one load of the hopper, but the new one easily makes it through two loads before starting up again, and catches up while I'm refilling. So yes, considering what I was working with before, I'm very happy with the new compressor.
I don't have room for a booth to blast in, so my setup is a 30-gal tupperware tub with a sheet of glass sitting over it. I have enough room to put a piece in the tub, and the glass minimizes the bounce-back of the sand. This setup worked really good for doing the carbs (which were completed with the old compressor) but its a bit more awkward with larger pieces.
The chemical strip seems like a good pre-treatment, although I've had bad luck with them before. Can you recommend any brand? The other question would be, do I really need to take everything down to bare metal before repainting? Most projects I've worked on seem to do well just getting a good smooth finish, making sure there's no obvious transitions between layers of paint, and having a surface rough enough for the new paint to bite in to. There's no noticeable rust in the frame, so I think its mostly going to be prep for the new paint. I'm repainting to the same gloss black, so coverage won't be an issue, but since I had to chop and weld the frame repainting is required. With the wheels, I'm trying to smooth up the various road nicks, then they will also be covered completely in gloss black. The tank came to me already primered, so the rest will be smaller pieces like the battery box (which does have a lot of rust), but those will be easy to do, even with the current gun I have.
She's a beautiful mess, and I've made her all mine