Sandblasting: Syphon vs. Direct Pressure

[akr]

I was wondering if anyone has had any experience blasting pipes with both a syphon system and a pressure system. I was thinking that a pressure system would give more control and would be better at getting deep craggy blasts, but I wanted to hear from you guys first.

Thanks,
akr

[KurtHuhn]

Blasting, unless you're aiming to do individually blasted rings with a custom gun/nozzle/pot setup, has more to do with your choice of media and compressor than it does anything else. The best, most detailed blasts I've ever seen, have been the product of a siphon system.

[akr]

Thanks for the opinion Kurt, I'm just trying to get a good sandblasting system and method worked out and there are a lot of variables to think about--type of media, grit of media, type of system (pressure vs. syphon) and cabinet and compressor, nozzle size, pressure used, how much media in the air stream (if using a pressure system), angle and distance you are blasting the pipe at, etc.--and on top of that you can blast in multiple stages changing these variables between stages. Good thing I love blasted pipes!

[Tano]

Hi Guys,

I'm no where near getting a sand blasting system, but my mind is always wondering. My shop (recently remodeled) is in my garage which is part of the basement. From what I have read in this forum an 80 gal. compressor would be a good choice, correct?
My question is where do most of you locate the compressor is it in the same room that you work in, and how loud is it?
Does anybody locate it outside, and if so, would the cold Canadian winters affect its performance?
Thanks

[KurtHuhn]

My compressor is, for all intents, outside. It sits in an open tractor bay attached to the main shed, and works fine all winter. The cabinets are in that shed, and there's about 4 feet and one inch of wood between them. I definitely know when the compressor is running, but the dust collector is louder.

An 80-gallon compressor typically does about 18CFM at 90PSI, right? If so, that's about what you want. Mine is a 60-gallon unit, and purports to do 15CFM at 90PSI, which is fine for my methods. Bigger is better, however, and more CFM means the compressor won't be constantly running while you're blasting.

[RadDavis]

My compressor is in the shop (garage) with me, next to my blasting cabinet. It's loud, and something else to consider is that the motor generates a lot of heat.

Getting a KNN air filter is supposed to make them much quieter, but I've been too lazy to try one out. I just put on my Mickey Mouse Ears.

You definitely want one that's running less than 50% of the time that you're blasting.

Rad

[larrysson]

akr,

Pressure systems are good...no better or worse than a siphon blaster...just different. Pressure systems cost more, so for the money, the best bet is a siphon. I use a pressure system myself, set up for hands free operation and triggered by a foot pedal. I wrote an article about the differences awhile back....you can read about it at http://www.larryssonpipes.com

[akr]

Thanks Paul, that was very helpful.

[RadDavis]

An 80-gallon compressor typically does about 18CFM at 90PSI, right? If so, that's about what you want. Mine is a 60-gallon unit, and purports to do 15CFM at 90PSI, which is fine for my methods. Bigger is better, however, and more CFM means the compressor won't be constantly running while you're blasting.

The tank size really has nothing at all to do with the air flow or the operating pressure of a compressor.

It's all about the horse power.

And it needs to be a 2 stage.

Rad

[KurtHuhn]

An 80-gallon compressor typically does about 18CFM at 90PSI, right? If so, that's about what you want. Mine is a 60-gallon unit, and purports to do 15CFM at 90PSI, which is fine for my methods. Bigger is better, however, and more CFM means the compressor won't be constantly running while you're blasting.

The tank size really has nothing at all to do with the air flow or the operating pressure of a compressor.

It's all about the horse power.

And it needs to be a 2 stage.

Yes, yes, and yes. But, generally speaking - in generalizations - the larger the tank, the better the pump and motor attached to it. At any given retail location, the 80-gallon models will have higher CFM/PSI rating than the 60-gallon models. Typically.