Looking for your help/comments please.

I bought a Clarke Boxer 55 Air Compressor some time ago. It has an Air Displacement of 12.2cuft/min with a 50 litre air receiver (appreciate should use Free Air Delivery but not sure how to work that out). The compressor is belt driven with a 3HP motor.

I later then purchased a Clarke ½” Impact Wrench with an average air consumption of 4CFM which looking at the spec would suggest that it would be compatible.

Only recently tried to use it and found that it would not deliver anywhere near the torque to loosen bolts etc. Took it back to the shop only to be told that the compressor cannot deliver enough air to drive the wrench. I have written to Clarke and awaiting a response. Unfortunately it has been too long since purchase to try and return same.

Just looking for any comments or suggestions either if it is correct that it is not compatible or is the wrench possibly faulty.

Is there any recommendations for a ½” or 3/8” impact wrench that would be compatible?

Thanks in anticipation.


Regards,

Arnie

what pressure are you running at

Mines 40 cfm, 150l tank, and runs an impact wrench ok. As above, check your air pressure, it should be enough to do it.
Mine did struggle the other day right enough, but I think thats because my air pressures were way off after spraying paint the other week, and I couldnt see the gauge to sort it

The displacement of the compressor gives you the free air delivery ie; at atmosphereic pressure. The demand of the tool, is it's requirements at it's operating pressue ie, 100psi.
4cu.ft/min @100psi = 27.2cu.ft/min @ atmospheric pressure.
A bigger receiver would help.

[Edited on 14/4/13 by Confused but excited.]

If you have a pressure regulator on the air receiver outlet remove it or by-pass it.

The wrench has a maximum rating of 90PSI. This is what the regulator is set at.

Regards,

Arnie

What diametre pipe are you using. The 8mm ID plastic curly stuff restricts the air flow too much. 10mm ID rubber is much better at allowing your impact wrench to deliver its full potential. With trhe smaller diametre pipe I can't even undo my wheel nuts which are tightened to 65ft lbs. With the 10mm pipe it will shift crank pulley and drive shaft nuts which are torqued to over 300ft lbs.

Indeed, the FAD is pretty irrelevant if the receiver is up to pressure. The pressure is dropping between it and the wrench.
I had a filter/regulator that was horrendously restrictive, and as above hoses need to be a decent bore, or the air just will not flow fast enough.

Of course the impact wrench may be playing up. Well oiled etc??

But 4cfm is really a huge porky, but any compressor will run any impact wrench. It is the time it can run it for that is the issue

A bigger air receiver won't help it will only allow the tool to run for longer bursts between exhausting the air supply.

As soon as the trigger the air starts to move the pressure at the far end of the pipe drops drastically.
Impact wrenches use a horrendous amount of air so the velocity of air going through the pipe and all of the restrictions such as the couplings and regulator is very high, as a result the impact wrench may actually be operating at as low as 20psi.

The ways to get round this are reduce the restrictions (bigger bore hose, ditch the regulator and run the compressor at the rated SWP which I would guess is about 10bar/150psi.

I run my impact driver on the max pressure in the tank, don't bother with a regulator at all

Thanks for all the responses much appreciated. The hose is 10mm so hopefully big enough. Will try the other suggestions to see if I can get it to work properly.


Once again thanks. All the best.

Regards,

Arnie

have you got an in line oiler? if not try dribbling a few drops of light oil and having another go. the tool should be oiled to prolong its life but it also helps with keeping pressure (well I'm sure someone told me that)

oh, happily use an Aldi gun on an Aldi 2hp compressor.

I have a 1/2" Clarke gun, it's rubbish.

Purchased a Bergmen 3/8" gun for £22 on eBay and its got twice the guts and 1/2 the size.

As above a couple of drips of oil into then gun and take the airline straight out the tank



Regards Mark

My experience is you can never have enough air esp with impact wrenches. I upgraded to:

http://www.workshopping.co.uk/product/compressor-270ltr-belt-drive-2-x-3hp-with-cast-cylinders/SAC1276B/

and still I run out of air occasionally (but not very often).