Tool Talk: Pneumatic vs. Electric

[Bird]

If it works I might start leaving my compressor on for ready air.

I know it might not be the recommended way, but I keep my compressor tank pressurized, hose connected, and blow gun on the end of the hose. Of course, it's only 12' from the back door to the shop door, across a covered breezeway, so when I shave with the electric razor, I step out there and blow the whiskers out of the razor. It I go out in the yard, I usually blow off the bottom of my shoes before coming back in the house. But insteas of one of the automatic drains, I replaced the petcock in the bottom center of the upright tank with an elbow, a short piece of pipe coming out to the edge of the tank, and a ball valve. So anytime I run the motor on the compressor, I then quickly open and close that ball valve to blow out any moisture.

 

[jimmer2880]

I have a Dewalt 18V impact wrench. While it's OK I have had two uses that it cost me. The first one it would not loosen the lugs nuts on my Tundra. It seemed to be working OK, but when I charged the battery it worked. The other times was using it to tighten the top nuts on my Dodge Caravan front shocks. I thought I got it tight, but it was still making a clunking noise. I took those shocks on and off three times and finally took it to the dealer. They said the nuts were loose. No problems after that. It does not behave like a pneumatic tool, so you have to be mindful.

If you are using Air or Electric, it's not very smart to not use a torque wrench when tightening nuts/bolts. If you read the manual, I'll bet you a dollar it agrees with me.

While I use my air impact and air ratchet to get the initial tightening, I always leave the last turn or 2 for the torque wrench.

It's a safety thing. You have to step up to some very expensive air tools to get one that accurately torques to the set amt.

 

[ultrarunner]

The machine shop had a project for NASA that stipulated only pneumatic or hydraulic power tools... no electrical equipment of any kind allowed...

 

[BobRip]

If you are using Air or Electric, it's not very smart to not use a torque wrench when tightening nuts/bolts. If you read the manual, I'll bet you a dollar it agrees with me.

While I use my air impact and air ratchet to get the initial tightening, I always leave the last turn or 2 for the torque wrench.

It's a safety thing. You have to step up to some very expensive air tools to get one that accurately torques to the set amt.

I agree, but the shock bolt is hard to put a torque wrench on. You have to hold the shaft with one wrench and torqued to nut.

 

[Cami]

@Iplayfarmer: 7 CFM for a 7" pneumatic angle grinder seems really low. Be cautious, I've seen air consumption charts that only assume a certain ammount of utilization; much less than continuous duty.

 

[JoelD]

Agreed on the 7 inch grinder, I couldn't imagine my 10cfm keeping up with that. A 2-1/2 cutting wheel runs my compressor down in short order. Those fast spinning tools need industrial strength compressors. I'll take my electric cutting wheel any day.

Joel

 

[dirt clod]

The machine shop had a project for NASA that stipulated only pneumatic or hydraulic power tools... no electrical equipment of any kind allowed...

interesting did they give any reason why? I Wouldn't think a small electrical motor would induce anything into metal

 

[Iplayfarmer]

@Iplayfarmer: 7 CFM for a 7" pneumatic angle grinder seems really low. Be cautious, I've seen air consumption charts that only assume a certain ammount of utilization; much less than continuous duty.

Could be.

I have heard, though, that the difference between a good high end air tool and a lower end air tool is air consumption. I know JET is a good name in woodworking tools. I would assume it would be a good name in air tools too.

What kind of CFM do you think a grinder like this ought to use?

 

[Bird]

I have heard, though, that the difference between a good high end air tool and a lower end air tool is air consumption. I know JET is a good name in woodworking tools. I would assume it would be a good name in air tools too.

What kind of CFM do you think a grinder like this ought to use?

When I was repairing air tools, Snap-On, Matco, MAC, Chicago Pneumatic, and Ingersoll-Rand were all good tools. But my best customer was a big company that had a lot of Sioux tools. In my opinion, Sioux makes by far the best, most powerul air tools. But if you look at the specs for the Sioux Pneumatic Grinders you'll see they're rated at 25 scfm (little die grinder) to 35 scfm (7" or 8" angle grinder). And yes, I think that's continuous running. I ran them enough to test them with a compressor that only put out about 11 scfm and using 1/4" and 3/8" air hoses; not what I'd have used if I were actually working them long and hard as their owners did.

Of course, a 7" Chicago Pneumatic grinder may use as much as 24 scfm.

As for Jet air tools, I was fortunate enough to only get two in my shop; an air hammer and a nibbler, neither repairable because no parts were available. They may be pretty good new, but I'd consider them like Harbor Freight tools; maybe good for the price, but disposable instead of repairable.

 

[ultrarunner]

interesting did they give any reason why? I Wouldn't think a small electrical motor would induce anything into metal

Don't really know all the details other than it was a safety precaution...

We had a contract to build rocket fuel mixing equipment for the Space Shuttle... the machines we built and serviced were also 100% hydraulic with Pyrogard fluid and Pneumatic controls...

At least I didn't have to worry about getting an electric shock because there was nothing electrical anywhere...