Blast Cabinet CFM

[Racinbob 11,718]

I'm considering purchasing a small blast cabinet. It's calling for 7 CFM at 90 PSI. My compressor is only rated at 5.8 CFM at that pressure. I'm under the impression that the main drawback would be having to wait now and then for the compressor to catch up. I'm sure some of you guys have used one under similar circumstances. How well did it work? 

[squonk 42,511]

I 've had 3 cabinets over the years. The only one that worked worth a Hill of Beans without a bunch of mods was a homemade cabinet using TP Tools equipment. That means TP gloves, gun, carbide nozzles, hardware and vac system. The big key is plumbing the air lines and getting the cabinet away from the compressor. Use metal lines to cool the air and condense the moisture out of the air before it gets to the cabinet. I have a 7SCFM 6HP compressor and yes if you really blast a lot it will have to catch up. I tell everyone who is interested in a cabinet to buy the biggest compressor they can afford and what their electric capacity will handle. Go to TP's website to read their tips and tricks for blasting.

 

https://www.tptools.com/

 

https://www.tptools.com/tech-metal-piping.dlp

 

airline-piping-diagram.pdf

Edited April 12 by squonk

[HyperPete 478]

I'm about to sell my 2-stage 60 gallon 10.5 CFM because it can't keep up.

Buy the most you can afford!

[Racinbob 11,718]

You guys just might talk me out of it. I found a good deal on an Eastwood B40 which is a decent size benchtop. For my needs it would be plenty big enough but if my current compressor isn't enough I'll pass. I'm not replacing the compressor.

[squonk 42,511]

20 minutes ago, Racinbob said:

You guys just might talk me out of it. I found a good deal on an Eastwood B40 which is a decent size benchtop. For my needs it would be plenty big enough but if my current compressor isn't enough I'll pass. I'm not replacing the compressor.

Depends on what you want to do. If you're just doing a couple of  small parts now and then it would be fine. But if you're doing wheels, engine blocks and fenders it's a different story

[squonk 42,511]

Another thing about CFM and compressor keeping up. One variable is the nozzle. A larger nozzle will need more CFM. As you blast the nozzle wears away. Some guns also have an orifice. You need the pressure differential in the gun to pull the abrasive up the tube. As everything wears the differential decreases meaning less abrasive is coming out. Just more air. So you end up blasting longer to get the job done running the compressor more. I used carbide nozzles which cost more but last about 10 times longer than ceramic

[Racinbob 11,718]

30 minutes ago, squonk said:

Depends on what you want to do. If you're just doing a couple of  small parts now and then it would be fine. But if you're doing wheels, engine blocks and fenders it's a different story

Exactly that. That's why this small one would be fine for me. 

[RJ Hamner 1,025]

I'd have to agree on the TP Tools comments  They have a tabletop model that is on sale.. And the comments about compressors are accurate..BUT.....

I bought a model 760 dxl some years ago.  Its a great item and Ive never had a problem with it.  When I need replacement expendables the customer service has always been great.

BUT...The pocket book being the limiting factor on my toys my compressor is a Craftsman 2 stage portable that I use at 90 psi. TP Tools also has nozzels for use with lower CFI's

And yes I have to play catch-up with the compressor at times BUT its a hobby not a business. I am "payed by the month" so time is not a real problem.

It works for me .

Just food for thought...Your mileage may vary!!

 

Bob

[ineedanother 1,389]

Something to consider too if you're not going to do a lot of blasting is whether or not you need a cabinet at all. I had one but got rid of it to free up some space. I don't ever do big jobs so I lay a tarp out and set the parts on old steel patio table and blast away. I use coal so what doesn't end up on the tarp is minimal. I siphon right out of the bag. That might not be the most eco-friendly approach but it seems like a reasonable setup for what I need.

[Handy Don 13,340]

3 hours ago, RJ Hamner said:

"paid by the month"

I like this idea!

[Racinbob 11,718]

15 hours ago, ineedanother said:

Something to consider too if you're not going to do a lot of blasting is whether or not you need a cabinet at all. I had one but got rid of it to free up some space. I don't ever do big jobs so I lay a tarp out and set the parts on old steel patio table and blast away. I use coal so what doesn't end up on the tarp is minimal. I siphon right out of the bag. That might not be the most eco-friendly approach but it seems like a reasonable setup for what I need.

 

As much as I like the idea of the blast cabinet that does really make a lot of sense. More pondering. 

[squonk 42,511]

My cabinet I built was made out of plywood from plans from TP. Built a metal frame with casters so I could move it. Had a foot pedal which was nice.

 Just took up too much room. Tried a HF cabinet but that needed too much work to be usable, The gun was crappy and I decided it took up too much room on the bench. (I got too much Junk!) Tried a used bench cheapie cab with lousy results. 

 

I bought a HF 20 lb. Pressure blaster after Christmas and some glass beads. Blasted a head and some engine tins and it worked quite well and stores under the bench

[rmaynard 15,912]

20 hours ago, HyperPete said:

I'm about to sell my 2-stage 60 gallon 10.5 CFM because it can't keep up.

Buy the most you can afford!

 

I agree. I have a Harbor Freight cabinet with loads of modifications. It works well, but my 3.7 HP, 11 CFM compressor can't keep up. It runs constantly, and sometimes if I'm working a particularly difficult piece, I actually have to stop and let it catch up. 

Bottom line is if you are serious about doing much blasting, over-buy on the compressor. If the blaster calls for X CFM @ Y pressure, double it, or at lease go 1-1/2 times over.

 

 

[HyperPete 478]

That looks like my compressor.  Maybe mine isn't 5 HP!