HF 1” Air Impact, low power

Hi

Can anyone advise me on how to configure this 1” air impact gun I bought from Harbor Freight?

It comes with a 1/2” ID barbed hose fitting but I switched that out to match the hose fittings I use in the shop ( I think these are 1/4”). I’m not really sure how to configure using barbed fittings and clamped hoses and no instructions are included.

it works on the standard quick connect fittings but even with 120 psi on a 60gal 12 cfm compressor I don’t think it is putting out anywhere near the rated 2000 ft/lbs of torque.

How do I know the impact gun is under performing? We were trying to remove a 1.5” cylinder rod bolt and the impact couldn’t break it loose but a 5’ pipe on a big pipe wrench (gripping a impact socket) with about 100lbs of pressure , broke the bolt free. I calculated the torque used to finally break it free with (lbs x distance) that’s about 500 ft/lbs of torque.

What am I missing with this HF impact gun that is preventing me from getting the rated torque out of it.....higher psi? Bigger hose? Etc
The specs say 90psi 10 cfm.

Definitely need a bigger air line. Commercial fittings are easily available for up to 1 inch size hose.

You're choking the air supply to the tool... Quick connects are bad for restriction. A 1/4 QC is the worst. Look at the "glad hands" pneumatic breakers use. Very low flow restriction.

If you must use 1/4 QC use 1/2 inch or bigger hose & barbed fittings to an air tank. No valves or QC. Then pipe the tank inlet to your 1/4 QC. You'll get a few good hits before the air in tank is exhausted. The bigger the tank the more hits before having to wait for the tank to refill.

Fixed a production machine operation this way. Machine needed large volume of air intermittently but only a small air supply hose available. Installed an on board storage tank.

I just bought one of the smaller HF 1" drive guns. Several reviews said they used it to break loose piston bolts. At least one review I read said they tried the long nose gun you have and returned it for the short gun. That review said the long gun didn't loosen a bolt that the short gun removed without a problem.

This is the one I bought but I haven't put it to the test yet. Download the 20% off coupon if you go to get anything there. I look it up on my phone and do a print screen every month so I have it saved in my photos.
https://www.harborfreight.com/1-in-pistol-grip-air-impact-wrench-62355.html

My gun came with a 3/8" NPT inlet and they supplied a fitting that had a 1/4" nipple. I bought their 3/8" high flow connectors which are 1/4" NPT pipe but have a 3/8" ID hole. I had to source a 3/8 NPT to 1/4 NPT adapter from Tractor Supply. My compressor is way too small but I'm going to try it before I go buy or borrow a bigger one. I installed the 3/8" connectors at both ends. The gun said to use a 1/2" hose but i don't see that as being a big advantage when everything else is 3/8".

Not sure yet if I will have any better luck or if it's even up to the task. I already failed to get my bolt loose with a 3' pipe wrench and a 10' pipe. Waiting on the 1-15/16" socket I had to order to attempt with the air gun. I'm probably going to have to take the rose bud to the bolt before it's all said and done. I should probably go ahead and heat that sucker up and let it cool while I'm waiting on the socket.

Right there is your problem IMO. The hose should be of the same inside diameter as the female thread in the black fitting on the end of the gun.

My rule of thumb for an impact gun is that the hose I/D should be the same as the size of the square drive on the business end of the gun. So by that rule a 1" square-drive gun should ideally be fitted with a 1" I/D hose, but certainly nothing smaller than 3/4".

A 12cfm compressor is probably a bit borderline but if you can configure an additional air tank to act as a reservoir then it ought to work OK.

I guess what others above are saying is your choking your tool.

I saw a feller that had connected a 100 lb. propane tank up to his compressor to increase the stored volume. It seemed to work pretty good.

Okay got it, I need more flow , but not necessarily more psi.
Do those barbed fittings just take a hose clamp to hold them on or is there some special crimp-on hose end collet that is supposed to be used?

I use a 3/4" factory made air hose with my large impacts. Those barbed fittings would work in a pinch, but probably not recommended and I suspect OSHA wouldn't care for it. If you care about that.

Birdseye said:

Okay got it, I need more flow , but not necessarily more psi.

Click to expand...

Think of psi as horsepower and flow as torque. Which one really does the work..?

Birdseye said:

Do those barbed fittings just take a hose clamp to hold them on or is there some special crimp-on hose end collet that is supposed to be used?

Click to expand...

I would just throw them away and start with something far better.

Ok so bigger hose and change out that 1/4” fitting for a big barbed fitting or a QC.

With that done and the bottleneck gone , is it your opinion that this impact would or could possibly deliver 2000 ft-lbs of torque.

Birdseye said:

Ok so bigger hose and change out that 1/4” fitting for a big barbed fitting or a QC.

With that done and the bottleneck gone , is it your opinion that this impact would or could possibly deliver 2000 ft-lbs of torque.

Click to expand...

You won't get 10 cfm through that fitting or the regulator. Put a tee after the valve on the tank ...then you will get 10 cfm to the tool using 3/4 hose and appropriate fittings.

The tool is rated to deliver 2000 Ft# IF it's air supply requirements are met. You haven't met its required air supply.

Well remember you bought a tool from Harbor Freight. I doubt you will ever see 2000 ft-lbs from that no matter what. As has been said you will need a BIG compressor capable of some serious air. You will want a 3/4" - 1" ID hose.

A friend who works at a heavy truck shop tried to help me get a bolt loose on a cylinder I was repacking. 1 1/2" air gun on shop air supply which use 1/2" hoses would not break it loose. He fired up a diesel trailer compressor they use for jack hammers and that air supply did the trick.

If you are trying to use this to break big bolts free you might find a torque multiplier a better investment.

As Nige says, one inch drive = one inch hose. It usually takes at least 20 CFM to run a one inch impact.

The cheaper the gun the more air it will take to run rated I have a 22cfm compressor with 3/4 hose and half inch fittings and I have to wait on the compressor when we are getting after it

psi and flow is far to low plus its a cheap gun but I think it should do what your asking A 1/2 inch hose at 175 psi will do what you need occasionally have cheated and ran 2 or three 1/4 inch lines into a 1 inch gun

Like Hosspuller said in post #3, I use a freon tank, with a 1/2 fitting to a 4' piece of garden hose to the inlet of that same impact. The 1/4" connects to the side of the tank fitting. I don't know if it gets 2,000 ft lbs, but it gets way more than what you're going to get going through way to small hose, filter and quick connects. You get a second of power and it drops fast after that, the size of the compressor hooked to the other end of the 1/4" hose only determines how long you wait to have another second of power.

The hose and adapter size is your big loss, just like everyone else just pointed out. I'll also tell you that you will experience some loss of impacting power by adding adapters to fit different drive size sockets. Those adaptors and/ or extensions will soak up some of the hammer action.

That ball valve is you are using can be a serious choke in the air flow. They typically have very small bores in the ball.
I always go at least one size larger than the line it controls.

PS ... I missed this nugget in your photo.. the rated power (2000 ft #) requires 10.3 CFM at (max) 135 psi. You don't have that air supply. So, you won't get 2000 ft#