- Thread starter lexi
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shenion
Tool Pack Rat
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I found the biggest difference was using a short hose. My die grinder was used on my 25' hose. I switched to a 10' hose and it has more torque.
I have a reel on the end of a 25'hose with another 25' on the reel. I have been thinking of running 1/2" iron pipe to the reel.
A big help for my sprayers is moving the regulator near the gun. I have several small regulators I clip right on tools or witha short hose. That keeps high pressure in the hoses for more flow.
I have a reel on the end of a 25'hose with another 25' on the reel. I have been thinking of running 1/2" iron pipe to the reel.
A big help for my sprayers is moving the regulator near the gun. I have several small regulators I clip right on tools or witha short hose. That keeps high pressure in the hoses for more flow.
irondarren
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Theoretically a 3/8 hose should be able to supply about 20cfm at about 90psi possibly more. Most 3hp compressors only have an output of 10cfm FAD. So there would be no real benefit unless you where doing something that required vast quantities of air in short bursts.
I have run various air tools on compressors using 3/8 hose from large standblast units to DA air sanders and its always been the compressor that causes trouble by not having the ability to produce enough air.
I have run various air tools on compressors using 3/8 hose from large standblast units to DA air sanders and its always been the compressor that causes trouble by not having the ability to produce enough air.
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Slightly off-topic but I'm after a new compressor and am a little confused as to which one to buy. The one I'm looking at is a sealey 3hp 200 litre which has a claimed MAX fad of 12cfm. Would this provide enough air to run a blast cabinet ok? Are manufacturers FAD figures accurate?
irondarren
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Watch manufacturers claims for Air, there are two ways to measure air, displacement and FAD (free air delivery) a reasonable quality 3hp compressor has around 14.5cfm displacement and 10cfm FAD. Many manufacters often list displacement in there specs, but air tools always have there requirements in FAD.
In answer to the blast cabinet yep it will work no problems, but most likely not for long before you run low on air, but you might have enough time to give the outside of a rear brake drum a nice cleaning, before air gets low and you just have to wait for the air to build up until you blast the next piece.
In answer to the blast cabinet yep it will work no problems, but most likely not for long before you run low on air, but you might have enough time to give the outside of a rear brake drum a nice cleaning, before air gets low and you just have to wait for the air to build up until you blast the next piece.
Horrorking
Welding anything I can!
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Yeah I did some tests with my 9cfm compressor just after I bought it. Alas 9 was a pipedream, and it delivers more like 6 to 7, but luckily it has a 100% duty cycle, so provided it is in free air, it happily chugs away constantly.
A lot of other people I know with smaller compressors have had similar results, but the larger compressors dont really serem to have such a large performance difference to the rating
A lot of other people I know with smaller compressors have had similar results, but the larger compressors dont really serem to have such a large performance difference to the rating
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I'm looking at just a small cabinet/gun. I don't want to spend several hundred pounds on a compressor only to realise it's not up to the job. (I did that with my butters welder). I've found another that has a claimed FAD of 12.9cfm, slightly more than the sealey but is it enough?
irondarren
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What is the cabinet specs for air requirement? or do you have a link to it?
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Haven't built it yet
Want to make a decent one though so want to make sure my air supply is adequate.
rtbcomp
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The size of the cabinet doesn't determine the air supply, it just dictates what you can fit inside!
The nozzle size and working pressure determine the air requirement.
I bought the Machine Mart free standing cabinet, the gun you get with it is useless, so is the internal light. I use an external pot, MM sell the Rolson one, (you can get them much cheaper on eBay) which is a very good machine, although the ceramic nozzles only last one potful of media.
My Clarke 14cfm cpmpressor maintains a pressure of 80 psi with a 2.5mm nozzle.
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I'm looking to build one big enough to clean wheels in and fairly quickly so a decent gun set-up is required meaning a decent air supply as well. Might even go for a pressure system instead of syphon. Spotted another comp last night, 28 CFM CAST IRON TWIN CYLINDER PUMP 210 RECEIVER 240 VOLT £798.00+vat. Probably needs a hefty supply though which may be a problem. The 28cfm I assume is the displacement but it should still give an excellent FAD.
rtbcomp
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Don't even consider a syphon gun, they eventually clog because they re-circulate the media without filtering it. They also use more air than a pressure pot. Use chilled iron grit, either G7 or G5, (I use G7) although it costs about £20.00 per bag you can use it about 300 times. Look to buying 4 or 5 bags to get a cabinet going. Don't use sand or single-use grit, they produce too much dust and you can't see what you're doing. You will need to sieve the used grit before putting it back into the pot
If you're doing wheels make a turntable that you can tilt away from you.
Don't forget you need something to suck the air out of the cabinet, I use a Clarke dust extractor although I'm sure it wouldn't be too difficult to make one out of an old tumble drier blower.
Don't use a Record dust extractor or a vacuum cleaner, they use commutator motors and are very noisy. The Clarke machine uses an induction motor.
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Excellent info, thanks Roger. 
What do you think of that compressor? Sounds great for the money, I've requested a catalogue. I'm looking at buying one I won't 'grow out of'. My little compair 2hp 50L has lasted me around 13 years and is still going but I know I'd kill it if I hooked it up to a blast cabinet.
What do you think of that compressor? Sounds great for the money, I've requested a catalogue. I'm looking at buying one I won't 'grow out of'. My little compair 2hp 50L has lasted me around 13 years and is still going but I know I'd kill it if I hooked it up to a blast cabinet.
rtbcomp
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Excellent info, thanks Roger.
My attitude is that you're better using a big machine for a small job rather than vice-versa!
If I was equipping a workshop from scratch I'd buy 2 off 14 cfm (3 hp) units and use them in parallel, the idea being that 1 unit will just supply enough air to do the job, so if one unit failed I'd still be able to get the work done.
The one unit gets hot after an hour's work (depends on the weather!) and once compressed air is hot it is virtually useless because it lacks mass and the moisture content increases.
