Impact wrench air requirements

[mike f]

I am in the midst of setting up my garage with lift and compressor. I have decided to fun 3/4" copper for all runs up to point of use (Ron, I looked into brass pipe-
) The compressor is a Bel-Aire 5 HP 2-stage which puts out CFM @ 100 PSI - 15.33
CFM @ 175 PSI - 13.75 MAX PSI 175. I was looking at some IR 1/2" impact wrenches. I called IR product support and they claimed that all their impact drivers run AT 90psi and no more. I was thinking of either the 2135Ti Titanium which will produce 1000 ft lbs reverse, or the IR232TGSL Thunder gun rated at 625 ft lbs. The problem is that when I spoke with IR product support, they said air requirements for these guns is in the 20-22 cfm range. Note, these are at max load and not avg requirements, which are much, much less. I am sure many of you use these thins without the 22cfm delivery. I realize that almost all of the time max load is only needed for very brief bursts (axles, shock towers and the like) but if I shell out the $$ for a superior wrench, I'd like to know that it will work for me. Of note, IR told me I should buy IR235, which only produces 375 ft lbs at load of 17cfm.
What are your experiences?

[greglepore]

That's why you have a tank, I think. The CFM put out by the compressor itself won't deliver max power to the gun, but you can flow greater than the compressor's cfm from the storage tank, limited by the size of hose, fittings and pipes. Maybe not for long, but you don't run an impact at max power for long.

[Rot 911]

Air impact tools really aren't air hogs like say an air sander or a sand blaster are. Your compressor is more than enough to run and impact wrench.

[mike f]

That's what I thought, but I guess the IR company wants to avoid complaints if/when things don't work the way the consumer intended. Which model do you guys use, if any. The thunder gun, at 625 ft lbs runs around $190 and weighs 6 lbs, while the Titanium at 1000ft lbs weighs 4 lbs and is about $260 including a 36 pc impact socket set (SAE and metric). I just can't think of anything right now that I would need the extra torque for, but I'd rather put out now for a tool I may need later than be stuck without it when needed. On the other hand, if it would never be needed I have plenty of things to spend the difference on!

[Rot 911]

I know lots of people are happy with the IR impacts. Bigger is always better. On the other hand I use the Central Pnuematics heavy duty impact wrench that I bought from Harbor Freight 5 years ago for around $40.00 that was able to easily remove the axle nuts on my 911 and you aren't going to find anything harder to remove on a 911 than the axel nuts. I also got a 50 piece metric/sae impact set of sockets from HF for around $15.00. They haven't managed to kill me yet.

[greglepore]

I'm with Kurt, although I will say that our experiences may not be representative. For general use around my shop the heavy duty IR clone H/F is fine, and if I need better I can usually borrow a bigger IR, even 3/4 in if needed. I'd let the deciding factor be weight, as a lighter gun is more useful. Mine was 40 bucks on sale, and has done everything asked thus far (no axel nuts or balljoint nuts yet). If you're willing to spend the IR dollars, I'd go for the lighter gun, as the sockets alone are at least half of the difference (if you don't already have impact sockets).

I'd also invest in some sort of inline oiler, but not if you plan to paint using the same lines. If you do, I'd set it up so the oiler is either t'd or on hose that plugs in, so not as to contaminate the entire system.

[edward993]

Mike,

As already mentioned, your compresser is more than adequate for home wrench use. It is sanders and grinders (and the like which see continuous use) that need highr CFM ratings and bigger tanks. For reference, I've got an IR wrench (think it is about 400lbs max) that works fine with my wimpy little HF compressor. Works great for everything, but could NOT break my axle nut loose ...but that was a shortcoming of my small compressor/tank whereas yours should be fine.

Edward

[SCOTITUDE]

I bought the Earthquake gun from Harbor Freight which is a knockoff of the large MAC gun. I run it at the track off of a small Porter Cable pancake from Home Depot. Works great. I haven't found a nut or lug on my car, truck or trailer that this gun couldn't turn off yet. The gun was on sale for $79. How can u go wrong considering the higher price guns get into the $2-300 range.

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93124

[VincentVega]

The 'thunder gun' is way loud, if that matters to you.

[David]

As others have mentioned I have a nice 1/2" drive IR for everyday use and a cheap 3/4" for the really tough stuff. The IR may be rated for 400ft-lbs or whatever, but it's the size of the hammer that matters.

[toolman]

I sell this stuff for a living. If you get one of the IR BIG guns, you are supposed to use 1/2" air hose to obtain that kind of volume. The best bang for the buck I sell is the IR231C (IR231H for handle exhaust). Should cost you about $130, and you can use 3/8" hose.

[rw7810]

Ok Toolman, thanks for advice. What do you recommend for a good shop garage compressor. I've been considering a IR SS3L3 3 HP with 11.3 CFM for $565

[euro911sc]

I got my IR from Sears same as Toolman sugested... I vote for a smaller gun. Sometimes its nice to have a lighter piece in your had when you have your arms in the air. Also, some spots on these cars are tight and a smaller gun goes more places.

The only time you may need a huge gun is the tranny nut or maybe something like trailing arm bolts after 25+ years... Like Scotitude said, there really isn't anything that the smaller onces cant take off.

Of course, if you are made of $$ get both

As to the compressor... way overkill unless you are using the sander. I have a small one with a 30 gal tank. Runs off 115 and I have yet to have any problems... (I dont use a sander)

-Michael

[mike f]

Looking at the HF site gave me some ideas. The thunder gun knock-off was going for $79. I guess if it is a decent gun then I can save some $$ and pick up either this $193/8" gun for light use, or this $28 1/2" gun for slightly heavier use. I realize that most times hand tools are used, but in tight quarters it may be of benefit to break bolts free with a small impact wrench than with skinned knuckes. Realistically, for the guys that own these tools, how often do you use them?

[greglepore]

Every major project on the car. I use my air rachet a lot as well-it doesn't break anything free or final torque anything, but for a project like removing 20 bolts from a 3 piece wheel, its da bomb.

[toolman]

Bob, That would be a good compressor for general duty mechanical and light to moderate painting. If you intend to do much sanding, sandblasting or painting, go with the 5HP-80 gl unit. I have the 2 stage 5HP-80gl and it does everything I could ever want. I don't know if they have Tractor Supply Co. by you but they usually have the best deals on IR compressors. Let us know what you end up with.