Compressor & Impact Wrench questions

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Hi,
My compressor is a 2.0HP, 50L direct drive model. I also have a Hilka air impact wrench that I got shortly afterwards. Links to the exact models ..
[url=http://www.ebay.co.uk/itm/SIP-Airline-RC2-2-0HP-50-Litre-230V-Air-Compressor-Model-No-05289-/200949175199]Compressor[/URL]
[url=http://www.hilka.co.uk/product_detail.asp?s=85151617]Hilka Impact Wrench[/URL]
First problem is that the impact wrench barely works at all. When I first got it I only had a very narrow bore hose so assumed that was the problem, and basically forgot about if for a while. Now I have a better hose, 8mm bore 5m with high flow rate connectors. However the air wrench doesn't seen to work any better. It spins freely when not under load, but putting it onto a fastener and pressing the trigger usually just gives a little sound of air venting and no movement. Whizzing it a few times free then back on the work it will then give a couple of knocks - sometimes that's all that's needed to shift something. If not I have to whizz it freely a couple more times, then back on the work for two or three more impacts.

So my question, does that sound like the tool is dud, or is it my air supply? I see that a 10mm hose is normally recommended, but on the other hand the function was basically unchanged moving from a 5mm bore to 8mm bore. If not the supply, is there anything in this sort of tool that could be fixed?

Second question, the compressor pressurises to 8 bar, but doesn't restart until the pressure in the receiver is down to something between 5 and 6 bar. Does anyone know if there's any way of adjusting this? This what the pressure switch looks like with the cover removed. The 10mm hex on top adjusts the high cut out pressure, but I can't see anything that looks like it could adjust the cut-in pressure.

4VPatPBzQhWfQVAAgDP1rw.png


Thanks, Tony S
 
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I'm afraid your compressor, rated at 8 cfm is too small......it needs a huge volume of air to run air tools - somewhere in the region of 14 cfm.
As you've found, 10mm air line is the minimum, and not the coiled stuff anyway.
By all means lubricate the vanes on your wrench by squirting some light oil into the air inlet but the wrench won't have much puff.
John :)
 
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Cheers, there's an oil port on the wrench, I've just squirted a dose of oil into there now and again. The wrench is always a bit slimy with oil so I'm pretty sure it's getting enough. The annoying thing is that I found that Thorite, who I bought the compressor from, actually sell this exact same air wrench and reckon it would be OK with that compressor. I guess I'm a bit dubious about the compressor rating in terms of CFM being the issue, since when the wrench sulks it basically draws no air at all, just that little puff. Excessive sudden pressure drop would make more sense as an issue, but wouldn't that be related to the size of the hose (which is 10mm) and the receiver volume rather than the pump output?
 
I'd like to bet the wrench would work well if connected to a large compressor, however there are a couple of tests you can try.....
If you take the end cap off you'll see some vanes slid into a rotor. These vanes need to allow the vanes to slide, so make sure they aren't sticking.
Another fault with these is the forward and reverse peg.....move it a few times and see if any power is restored.
Both of these symptoms manifest with an air escape chuff from the gun rather than any spinning.
I'm afraid you are going to be somewhat delusioned using an air wrench with this compressor.....great for a blow gun, paint spraying or tyre inflation but it will be limited with much else.
John :)
 
Pop along to a local garage or tyre shop and ask if you can plug your gun into. Their supply for a test. Assuming the connector is the same
 
Could I just confirm something, to make sure I'm not complete misunderstanding? If trying to undo something that's simply too tight for the wrench, shouldn't the hammer still fire? Intuitively it seems to me that it should, otherwise it's not even trying. My experience so far has been that if I can persuade it to try, it's always succeeded in undoing what I'm working on, the problem is persuading or tricking it to try in the first place. For example on a mower blade last weekend it didn't try until I'd applied it forwards to the bolt, tightening it, then going into reverse it undid the bolt straight away.

I did some quick tests this evening, and it seems it always works in forwards, something I can't remember trying systematically before as my main use is undoing things where it's difficult to hold the work still. Testing with a 16mm nut and bolt in the vice once tightened fully it would still hammer in forwards even though the bolt couldn't and didn't move any further. Switching to reverse all I got was the puff. A couple of cycles of firing forward for a fraction of a second, then switching to reverse, and it fired up to undo the bolt.
 
Pop along to a local garage or tyre shop and ask if you can plug your gun into. Their supply for a test. Assuming the connector is the same
I know someone with a much bigger compressor, but he's away at the moment. I'm still not clear how the pump output affects a tool that doesn't draw enough air to start the pump running at all, this air stuff seems counter intuitive. However it's an obvious thing to try.
 
Presumably when you got it you fitted the adaptors? Did you use Ptfe tape? You may just have a leak
 
Hi,
My compressor is a 2.0HP, 50L direct drive model. I also have a Hilka air impact wrench that I got shortly afterwards. Links to the exact models ..
[url=http://www.ebay.co.uk/itm/SIP-Airline-RC2-2-0HP-50-Litre-230V-Air-Compressor-Model-No-05289-/200949175199]Compressor[/URL]
[url=http://www.hilka.co.uk/product_detail.asp?s=85151617]Hilka Impact Wrench[/URL]
First problem is that the impact wrench barely works at all. When I first got it I only had a very narrow bore hose so assumed that was the problem, and basically forgot about if for a while. Now I have a better hose, 8mm bore 5m with high flow rate connectors. However the air wrench doesn't seen to work any better. It spins freely when not under load, but putting it onto a fastener and pressing the trigger usually just gives a little sound of air venting and no movement. Whizzing it a few times free then back on the work it will then give a couple of knocks - sometimes that's all that's needed to shift something. If not I have to whizz it freely a couple more times, then back on the work for two or three more impacts.

So my question, does that sound like the tool is dud, or is it my air supply? I see that a 10mm hose is normally recommended, but on the other hand the function was basically unchanged moving from a 5mm bore to 8mm bore. If not the supply, is there anything in this sort of tool that could be fixed?

Second question, the compressor pressurises to 8 bar, but doesn't restart until the pressure in the receiver is down to something between 5 and 6 bar. Does anyone know if there's any way of adjusting this? This what the pressure switch looks like with the cover removed. The 10mm hex on top adjusts the high cut out pressure, but I can't see anything that looks like it could adjust the cut-in pressure.

4VPatPBzQhWfQVAAgDP1rw.png


Thanks, Tony S

Link to your wrench isnt working but after searching, I think I found the one you're talking about and it suggests 90psi working air pressure which is little over 6bar. You shouldn't need to adjust your pressure switch to turn on any sooner. Also that motor won't have a duty cycle rating to continually restart to keep the receiver under pressure. It'll bog down and stall the harder you run it. I have an identical compressor and I find this is the problem when using the blower to dispell a lot of air when dusting.

I'm afraid your compressor, rated at 8 cfm is too small......it needs a huge volume of air to run air tools - somewhere in the region of 14 cfm.
As you've found, 10mm air line is the minimum, and not the coiled stuff anyway.
By all means lubricate the vanes on your wrench by squirting some light oil into the air inlet but the wrench won't have much puff.
John :)

8CFM refers to displacement in the compressor. Has no effect on the tool, just the time it takes to charge the receiver and how hard the motor will have to work. No need for anything greater. 8 bar working pressure is 8 bar working pressure regardless of the motor running or not.

Presumably when you got it you fitted the adaptors? Did you use Ptfe tape? You may just have a leak

A small leak wouldn't make that much of a difference.


OP, I'd look at the tool. Truth be told, £40ish (if it's the right one I've found) is fairly cheap for an impact wrench so I wouldn't hold it to a high standard. From what I've read it's rated at 311Nm which will be breaking/back out torque, often given as it's highest rating to sell the unit. I'd expect it wouldn't be any more than 200Nm normal operation. So basically I wouldn't consider it much good for breaking wheel studs. Could be wrong.
 
Links in this post may contain affiliate links for which DIYnot may be compensated.
Cheers. I think I'm going to tear into it. I really just got it because I had the compressor already for other reasons, so thought I might as well. It comes in handy where it's difficult to hold the work still rather than where huge force is needed. For some reason I duplicated the link to the compressor, the tool is here .. http://www.hilka.co.uk/product_detail.asp?s=85151617
I paid I think £39 for mine, what looks like identical product is sold under various names like SIP, Clarke or unbranded for various prices.
 
Cheers. I think I'm going to tear into it. I really just got it because I had the compressor already for other reasons, so thought I might as well. It comes in handy where it's difficult to hold the work still rather than where huge force is needed. For some reason I duplicated the link to the compressor, the tool is here .. http://www.hilka.co.uk/product_detail.asp?s=85151617
I paid I think £39 for mine, what looks like identical product is sold under various names like SIP, Clarke or unbranded for various prices.

For the money this looks a lot more worth while.

https://www.screwfix.com/p/erbauer-...odww0JSA#product_additional_details_container
 
I had the same problem with an impact wrench from Aldi, the first one wouldn't start, it's replacement is better but hardly powerful.
 

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