HFT 40lb blast cabinet

[LarryB]

I have had nothing but problems. It will not media blast. The siphon was replaced with gravity feed out the bottom drain hatch with 1" pipe fittings & 1/2" ID barb. All high flow fittings from the air-compressor (29 gal, 2hp, 150psi-max, 9 cfm @ 90psi), 20gal spare tank, & a new blast gun.
Still no media.

 

[txvwnut]

You need more compressor. I have the same cabinet with the TP Tools gun upgrade kit and it works great. My compressor is a 2 stage 20cfm unit with a 60 gallon tank.

 

[nmk_61802]

You need more compressor. I have the same cabinet with the TP Tools gun upgrade kit and it works great. My compressor is a 2 stage 20cfm unit with a 60 gallon tank.

This....What gun & orifice combo is that? I see that gun listed multiple places with a 9-18 CFM requirement dependent on the orifice. Media also looks dirty, how are you keeping it from clogging the gun?

Edit to say, try turning the air pressure down and opening the bleed valve a little more to see if the venture can get going with the lesser CFM. You may not be able to blast off heavy scale, but should be able test the air flow theory. Again that gun says it needs a 1/16" orifice to flow less than 9cfm @ 90 PSI. I'm guessing that you have larger than that.

 

[Spitfiremk16]

You need more compressor. I have the same cabinet with the TP Tools gun upgrade kit and it works great. My compressor is a 2 stage 20cfm unit with a 60 gallon tank.

I am running the exact same setup and mine works great. It was well worth the money spent.

 

[driftpin]

Please divulge the material of this valve, as I may have discovered a problem in your system.

 

[Damon L.]

Am I missing the foot pedal or something? How is the air flow actuated?

 

[Jswain]

Looks like you have the air unregulated going to the cabinet. Get rid of that plastic/PVC valve and put a brass valve in its place and also regulate the pressure down between 40-90psi.

The higher the pressure the more air you need in the venturi to keep the larger amount of material flowing without getting plugged. Start with 60psi and the venturi around half open and go from there

I missed it first that it was a spare tank so perhaps you do have it regulated, if not try what I said. Hold a gloved hand over the nozzle of the gun and open the air to blow the suction line out good then try. If you get media for a bit then clogs you need more venturi/less pressure/drier or cleaner media

 

[gregs]

Having just recently finished my cabinet project I can weigh in on what I think are the top issues you have to tune. Everything is completely dependent on how much air flow you have available on a consistent basis. It has to be dry as well. After that you choose your media & size, nozzle size and orfice size to match. To big of either and it doesnt work, and to small it will take forever to get anything done. If the media is to big(coarse) and heavy it doesnt have enough velocity to work well and if its to small(fine) it doesnt "cut" well and takes a long time to get something done. It definitely takes some work to get it "tuned in", but after that your good to go.

 

[MoonRise]

Couple of thoughts.

First, your compressor is NOT supplying 9 cfm @ 90 psi. That compressor is 'rated' to supply ~5.x cfm @ 90 psi per Harbor Freight.

Harbor Freight Tools – Quality Tools at Discount Prices Since 1977

Harbor Freight buys their top quality tools from the same factories that supply our competitors. We cut out the middleman and pass the savings to you!

www.harborfreight.com

Do NOT use that plastic water valve in a compressed air system.

The blast cabinet is 'rated' as requiring 9.5 cfm @ 90 psi. But that actually depends on the specific nozzle orifice being used.

So the cabinet actually needs about 2x the amount of air that your compressor can supply (other than for short bursts of usage where you use the air for a few seconds and then you have to wait for the compressor pump to refill the air tank and then you use the air for a few seconds more and repeat).

Your secondary Craftsman air tank does NOT give you more air. It gives you a little more air storage capacity (not a bad thing) but it does not give you more CFM.

And depending on the exact air lines going from the air compressor to the Craftsman air tank and all of the fittings and the air pressures at the various places in the system (and what you have the pressure regulators set to at the HF air compressor and then the Craftsman air tank), you could have less actual air flow than you think/want/need.

The air MUST be dry, or you end up with water (vapor and liquid) from the compressed air wetting the blast media. Which then clumps up and does not flow.

Speaking of media, is that actual sand? You do NOT use sand as the blast media (despite the blaster being called a 'sand blaster'). Because of silica in the sand, which gets airborne and gets in your lungs and gives you silicosis. Yeah, blasters used to use actual sand (sometimes) but then folks found out about the dangers from the silica.

And as mentioned, you have to balance the air pressure and the nozzle/orifice size and the media size to get things to work.

 

[MoonRise]

Oh, and read through the 'sticky' at the top of this forum section about Media Blasters.

The Abrasive Blasting Resource Thread

Edit: Keep checking on all the various links throughout this thread, as some are ongoing projects and may have had information added since you last viewed them. There are lots of GJ members who have blast cleaning equipment, so I am starting this thread for all of you to input information and...

www.garagejournal.com