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Impact gun?

My kid got a low priced air impact. He Used it once? I might use it this week. It says 425ft/lbs at 90 psi. Really? Do labels lie?

I’ve got a cheap one. I don’t know what it’s rated at. It doesn’t loosen tight or rusted bolts very well but will save effort spinning them off and spinning them on. Works fine for tightening smaller bolts. For large ones I just break them loose first then use the gun. I can’t justify a high priced unit.

I think the low-priced Harbor Freight stuff is a joke in a professional shop but just fine for a DIY’er. Those cheap units should serve you just fine. Take good care of them and don’t abuse them. I can tell you that they will not last in an industrial setting with air cranked up to 160psi and getting thrown around all day. For that you need Ingersoll or Snap-On. I have a 3/8 air ratchet I paid over $300 for in 1996 that is still going strong today, and an I-R 2135 impact that’s got to be almost 15 years old.

425 ft/lbs sounds about right.

I have a low priced HF air impact gun and a HF electric impact gun and the electric one works better. Have had it about 15 years and paid 36 dollars for it. Use it mostly for rotating tires and taking blades off my mowers and wheels on the rider.

I recommend Ingersoll-Rand or Chicago Pneumatic for diy guys

i think it is a HF model

They’re probably referring to the thread size, not the size of the bolt head.

Yoy don’t think IR is good for us in tbe field?

Sure. But I’ve had HF impact guns and compressor for years now and they’ve both worked flawlessly. While they might not last in a professional shop, they’re great for home use. IMHO HF is underrated. Others feel differently.

To me, the biggest things your son needs to understand are that some bolts on a car are torqued to far higher specs than his gun is rated at (my strut bolts are 170ft-lbs), and that “breakaway torque” is much higher than application torque. A bolt torqued to 400 ft-pounds may take 500 ft-lbs or more to break free, especially if it’s been there awhile. In short, if your son’s impact wrench won’t loosen a particular bolt, he should find out what that bolt’s torque spec is. Also, he should never use the impact wrench to install nuts and bolts. He can get into big trouble very fast doing that.

might try it

Sure, I do. They’re up to the task

But it sounded like the initial questions in this discussion were about the more inexpensive air impact wrenches

Anyways, I have two 1/2" drive impact wrenches at work. One snap-on and one IR titanium. The snap-on has a little more power and is more comfortable to hold in your hand, but it’s also been the more unreliable one, and has now been relegated to back-up status. The IR titanium is the daily-use tool.

We have 2 air compressors at work. The main one is an IR. It’s faithfully been doing its job for years, with insufficient maintenance, I might add. The guys that are supposed to maintain it regularly seem to be shirking their duties, and I’ve got enough to do at work, that I’m not about to add that to my list of things to do. I’m not sure what brand the back-up is.

As far as the more expensive air tools go, I think IR is a good bet. Next time I’m in the market for an air tool . . . possibly another 1/4" drive air ratchet . . . I’ll consider IR.

Like 6" channel locks My shop had more impact wrenches than I could keep track of and most were cheap throw aways but for years I kept a top of the line Snap-On put away for when something tough came along. My Snap-On distributor always had a few bargains and when he had a like new Mac for ~ $100 I bought it and found that it was noticeably stronger than the Snap-On so it became the new HULK. That top of the line Snap-On likely cost $500+ 30 years ago but I still have it and it works fine even on 110 psi here at home but I rarely use it. The Mac evaporated like so many tools have done since I retired. But a Harbor Freight electric might be all that I need these days.

I still have more 6" channel locks than I can keep track of.

One thing you have to keep in mind if you use an impact gun is that any sort of socket extension will significantly reduce the torque delivered to the bolt. The impact, instead of loosening or tightening the bolt simply winds up the extension like a torsion bar spring and between impacts, the extension unwinds.


I am working on my rear brake drum/knuckle assy. I backed off the star adjuster for the brake shoes but they would not retract. How did I know? Drum would not come off. Than I opened the bleeder screw for the wheel cylinder and than the shoes retracted. And I got drum off. Is that common practice to make the worn shoes retract enough to clear ridge inside drum?

Possibly, because modern drum brakes adjust at the top just below the brake cylinder. The cylinder pistons slowly move outward as the adjuster does its job. Exactly why the spring holding the brake shoes together couldn’t overcome the hydraulic resistance back through the brake line and ABS to the master cylinder, I don’t know. You might have the beginning of an internal brake hose problem for that wheel.

Another reason I don’t like drum brakes. The last one I did was the rear brakes on my Park Ave. Then to adjust the shoes you were supposed to use a special measuring tool to set them. No more star adjustment. Never figured out why. I broke my spring tool anyway so I’m never doing any more.