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Hey folks! Just bought my brand new shiny blast cabinet. I also included a pressure control and a water trap. Everything is functioning properly.

When I begin blasting my briar, it doesn't blast material off hardly at all! I am using a #4 nozzle, running around 90psi from my compressor, and using extra fine 170-320 glass bead.

Any advice?!

hutchpipes wrote:Hey folks! Just bought my brand new shiny blast cabinet. I also included a pressure control and a water trap. Everything is functioning properly.

When I begin blasting my briar, it doesn't blast material off hardly at all! I am using a #4 nozzle, running around 90psi from my compressor, and using extra fine 170-320 glass bead.

Any advice?!

Could be the briar. Could be the nozzle. Could be the cfm. So many variables.

If you are using siphon, 80 to 120 psi is normal for decent blasting at 10 to 14 cfm.

I looked at my compressor and my issue could be my CFM is only 7! It's a 30 gal compressor too.

hutchpipes wrote:I looked at my compressor and my issue could be my CFM is only 7! It's a 30 gal compressor too.

My first compressor was 30 gal too. It will work, but it takes *forever* for it to refill...at least mine did. you might try blasting the side of an unfinished block - like Premal said, you'll occasionally find a block that is just really hard. All in all you probably just need to experiment a little more. Don't be discouraged yet!

hutchpipes wrote:I looked at my compressor and my issue could be my CFM is only 7! It's a 30 gal compressor too.

That's it. If you cannot get another compressor, get a pressure pot. Then you can blast at much lower pressure and cfm fine.

I looked at compressors online that will push that CFM and dang, those are expensive. Not sure I've heard of a pressure pot. What are they?

hutchpipes wrote:I looked at compressors online that will push that CFM and dang, those are expensive.

A 30 gal. compressor will take forever to blast. Like Ernie, I had a 30 gal. compressor and it gave me, maybe, 30 seconds of blasting.
I realize it's expensive, but for our needs, a two stage, 5+ hp, 60 or 80 gal. compressor is what's needed.
Check out this site, their prices are quite reasonable: http://www.aircompressorsdirect.com/

You can blast a pipe with that compressor, but it'll take forever. The cfm rating of the gun does make a difference. For example, the harbor freight cabinet consumes a higher cfm than the one by Cyclone. No substitute for the 5hp 2-stage, though.

First of all, this discussion reminded me of a very true quote:
"In metric, one milliliter of water occupies one cubic centimeter, weighs one gram, and requires one calorie of energy to heat up by one degree centigrade - which is one percent of the difference between its freezing point and its boiling point. An amount of hydrogen weighing the same amount has exactly one mole of atoms in it.
Whereas in the Amercian system, the answer to "How much energy does it take to boil a room-temperature gallon of water?" is "Go fuck yourself" , because you can't directly relate any of those quantites."

So all the gallons and cubic inches per feet (I think you invented this unit by dropping a cubic inch of steel on your foot and measuring how bad does it hurt) make me confused...
But I disagree- yes you can blast with a 30 gallon compressor. That's all I have and it works fine. It runs more than half of the time that I blast, but it works.
It depends on what you consider a reasonable amount of time to get a good blast. If you want to do it in 10-20 minutes, no way. But if you're ok with spending an hour or two and doing 3-4 runs on one pipe, it works.
I'm actually thinking about adding a siphon set-up to improve my blasting possibilities, but I plan to do it with the same compressor, an upgrade to a bigger one doesn't make sense for me for now if I can make it work. At some point in the future, when I upgrade my compressor it will be a 10hp screw compressor and then I will conquer the world with the best blasts evaaar!!

Well fellas, I've spent all morning in the shop trying to blast with my old 30 gal. I've used every tip that came with my gun and I still don't have a finished blast on a pipe.

FRUSTRATED.

I only had budgeted the cabinet and all the accessories. Now I'm looking at trying to buy a compressor that will work. At this point in just looking for an economically feasible way to blast. I can't afford a 2stage 5 horse compressor. What will work y'all?!

Found this at Lowes for 500. Thoughts?

http://m.lowes.com/pd/Kobalt-3-7-HP-60- ... or/3370356

That one will do better than what you're using but it's not going to keep up and you'll likely end up frustrated with having to wait for the psi to catch up. Unfortunately, with sandblasting it's go big or go home, IMHO.

hutchpipes wrote:Found this at Lowes for 500. Thoughts?

http://m.lowes.com/pd/Kobalt-3-7-HP-60- ... or/3370356

That's a single stage............you need a two stage.
My father always said: "Any jobs easy as long as you have the right tools." I've found this to be pretty much true.

The idea that you "need" a two-stage is not quite right imho.

Here's why: At lower pressures, let's just make a not quite arbitrary cut off of 100 psi for our argument, at lower pressures, single stage pumps are more efficient than two stage pumps. At very high pressures, let's say 150 psi and above, two stage pumps are more efficient, and the higher the pressure, the wider that gap is.

If you are looking to blast between 100 and say... 120 psi or so, this is exactly where the curves on the efficiency graphs intersect.

So for example I bought a big single stage twin pump compressor, 80 gallon tank, and it's fine for blasting consistently at 120 psi. A twin stage might run less, but my compressor catches up with my blast cabinet after a few minutes of blasting. But it's also putting out a pretty respectable 16 cfm at 90 psi, which is near double what the one Hutch is looking at. (Compare a similar two stage at 18.5 cfm at 100 psi - that's better, but it's not twice as better).

So I'll suggest that a real beefy twin-pump single can do the job. If you are blasting tons of pipes or running a real high pressure cabinet, a twin stage would be better.

No chance I can afford a 2 stage. So what compressor do you use Sasquatch?

I'll jump in on this thread and piggyback my own question, if I may. I rent, so installing 220 service is not an option.

Question: given a pressure pot setup, a low cfm nozzle, and the beefiest 120V compressor I can find, am I going to be super frustrated? Basically, ignoring the idea of farming out my blast work, my options are to go with a less than ideal setup or to wait multiple years before I can go all the way. I'm leaning towards the do it now option, but I'm also of the "buy once, cry once" mentality.

Ok, so sometimes the good Lord just gives you what you need. Was talking to one of the maintenance guys at the outdoor adventure camp I work at and he said, the compressor in the waste water treatment plant is pretty big. Can you use that one? This is what I found. I think that 18 CFM at 175psi will work right?!

Instead of replacing your compressor, you could just get a pressure pot and some accessories for about $200.

Of course, you will then have to do quite some work to get it running.

The nozzle that came with my cyclone cabinet didn't work great either, even when I switched out the 15cfm orifice for the 5cfm one. I ordered a ceramic nozzle with a smaller hole and it made a huge difference. I still can't blast super fast but I generally take 30-60 minutes with a 10 gallon, 5.4cfm @ 90 psi compressor. Yes, it runs pretty much constantly when I blast but it keeps up pretty well.

My father always said: "Any jobs easy as long as you have the right tools." I've found this to be pretty much true.

Bruce is not kidding, guys. I sneaked into his shop last week and snapped this pic.

5000CFM @ 125 psi

The man does not mess around.