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Pneumatic tools

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Nunyas

Nunyas

Yoda
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I recently bought a pair of pneumatic tools (CH... they were on sale in addition to Osh paying the sales tax! less than $30 each!): an impact wrench, and a ratchet. I found that the aircompressor that I have access to doesn't seem to supply quite enough juice when I set the pressure to 90. I was wondering, how in advisable is it to turn up the pressure to 100 or even 120 to be able to deliver the flow rate needed while the triggers are pulled?

Also, is it possible to repair a quick disconnect/connect fitting on a hose, or is that one of those parts that you just replace when it goes bad? The fitting seems to leak a bit if the hose to tool connection isn't positioned "just so"...

Thanks for any input guys!
 
Hard to say with cheap tools, but I've run mine up to 150 psi with no problems. Sounds like your real problem is hoses that are too small, though, or possibly something wrong with the tools. Impact wrenches in particular have a lot of variation between units, and it's practically impossible to actually get the rated torque out of them. Or it may be that your compressor just isn't keeping up.

In theory the seal in the better quick connects is replaceable. But the most common type ("Milton" or "Industrial") seems to always leak a bit, especially the cheap ones. I've had much better luck since I switched to "Tru-Flate" (aka "automotive") type plugs & couplers.
https://www.mcmaster.com/param/html//qdcouplings/6534KAC.pdf
 
DNK said:
Rob, is it leaking at the threads?
Click to expand...
no, it only leaks after I plug a tool into the connector; no tool no leak.

TR3driver said:
Hard to say with cheap tools, but I've run mine up to 150 psi with no problems. Sounds like your real problem is hoses that are too small, though, or possibly something wrong with the tools. Impact wrenches in particular have a lot of variation between units, and it's practically impossible to actually get the rated torque out of them. Or it may be that your compressor just isn't keeping up.

In theory the seal in the better quick connects is replaceable. But the most common type ("Milton" or "Industrial") seems to always leak a bit, especially the cheap ones. I've had much better luck since I switched to "Tru-Flate" (aka "automotive") type plugs & couplers.
https://www.mcmaster.com/param/html//qdcouplings/6534KAC.pdf
Click to expand...
The compressor is a Craftsman w/ 5gal tank, and I use a 3/8 ID hose with the tools. When I tried out the impact wrench, I noticed the measured static pressure (90PSI) on the compressor/tank would drop to about 60PSI whenever I pulled the trigger; it couldn't break the lugs loose on my car.

Ideally, I'll get a compressor with a larger tank so I can provide the appropriate flow rate with the compressor set to 90PSI. I was mostly wondering short term, if running up the PSI would blow out the seals.

Thanks for the info.
 
Volume is key, more is better for "windy" tools... doubt the seals would care if you went to 100PSI. The cheaper couplings are short-lived, but Milton should be okay. I've always used the Lincoln ones, longer tubes, less point stress on the seals/fittings.

You saw my set-up here at the hovel. It'll keep up with most air tools with 100PSI as the high point shut-off. kicks back in at 60PSI, so there's some waiting if I use an air board-file or D-A any length of time. The 1/2" CP air wrench has never failed me.
 
Nunyas said:
When I tried out the impact wrench, I noticed the measured static pressure (90PSI) on the compressor/tank would drop to about 60PSI whenever I pulled the trigger; it couldn't break the lugs loose on my car.
Click to expand...
For maximum run time, the hot setup is to turn the tank pressure up and use a regulator to drop it to 90 psi.

I got tired of the "compressor too small" blues and found a used 80 gal 7 hp unit on Craigslist for $500. Too big for the garage, so it's mounted in the backyard and piped in. Best "home improvement" project yet :smile:
 
see; now yer just braggin' :laugh:

I'll have to take a poke around at that local shops to see what I can find for hose fittings
 
Lots of loss can be had at the couplings.Different styles can "fit" together, but horribly restrict the airflow. I'd recommend getting a new hose end a matching coupler to go on the tools. Don't get the "universal type" get a specific kind and make all your tools comply.
For something like an impact gun, you're using short spurts of air. Crank it up! I max mine out at 120 psi on my Craftsman 20 gal. I used my airtools everyday for years at the dealership at 150 psi. They won't blow out. If you're running a die grinder, or something else that runs for a longer time, turn the regulator back down. but for max torque in short bursts, crank it!
 
Also- the longer your hose is the less volume you get. For a home unit I generally try to use a GOOD 25' hose max- anything longer really cuts the flow.
Another thing- you say that you have a 3/8" line but my bet is that you have 1/4" fittings on the ends (common practice) which have a 3/16" diameter orifice on the male end so if you are joining multiple hoses you are again killing your flow.
Use one 25' hose and move the compressor to the work.
BillM
 
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