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THE prop torque wrench

scard

Well Known Member
Advertiser
Sorry, shameless repost from my build log tonight:

Oh, man, I'm feelin' the love tonight. I got to use my new super duper torque wrench.
Most of us little people kludge together some mechanism by which to torque the prop bolts. This is a very important operation, however, that mechanism is usually questionable at best and potentially a real pain. After my previous final torque operation, I ordered THE correct wrench setup from the local Snap-on dealer (thanks Shane) and waited the requisite number of months for them to mine the ore to make the wrench and prepare it for my use. It, and the beautifully forged 5/8" open end attachment arrived and sat in its case for many more months. Yeah, I hear that I'm going to need a different size wrench for my next prop.
Today's operation for the condition inspection was to pull the prop, inspect, and reinstall. Using this wrench to torque the prop bolts to 45-55 ft-lbs. was a complete pleasure. No tendency to round off the bolts! No almost, or sorta' kinda', no oops, only delivery of the precise torque to each bolt. Without question, and with just the right amount of leverage to not strain a single muscle. $700+ later, it produces the most pleasurable, painless, and certain prop bolt torque experience possible on this planet :).
Different things make different people happy. This is my bliss. The right tool for the job. If you have a prop in the local area that needs to be torqued, "I torque for beer".
(dual income, no kids)

 
I know an A&P who's been one for over 50 years that's never owned a torque wrench...


Like pilots, there's A&P's and there's A&P's...When I flew certified planes, I used to go to ones that used manuals and torque wrenches...but I think they charge more too...:)

That is a beautiful wrench, no doubt. I use a Craftsman which I sent off (for $25.00) calibration/certification ...along with a crow foot wrench attachment. This offsets a little which allows it to get on the bolts on my M-T, which a standard open end wrench won't fit over and still have room to turn.
 
I have a nice torque wrench, but nothing that fancy, I'd like to get one for the 3/4" and 5/8" Lycoming props...
 
I use a Craftsman which I sent off (for $25.00) calibration/certification
Say, where did you have this done? I'd like to do the same.
...along with a crow foot wrench attachment.
Does the use of the crow foot throw off the torque setting, or do you keep using the same setting as with a socket?

TIA!--
 
Say, where did you have this done? I'd like to do the same.
Does the use of the crow foot throw off the torque setting, or do you keep using the same setting as with a socket?

TIA!--

If the crow's foot is perpindicular to the handle, it's the same setting. Torque is force times normal (perpindicular) distance so if the extension, crow's foot, etc is 90* to the handle you can use the same setting.
 
Nice Wrench!

Climbing the stairs to the Snap-On truck is a dangerous undertaking. It is guaranteed to give you great delight, but it will leave your checkbook weeping! Also, remember that when buying tools one must square the cost of the tools to assure matrimonial harmony. i.e.: $700 wrench + $700 couch = $1400 actual cost for the wrench!!
I have always used the crows foot at 90 degrees to the wrench to torque the Hartzell props. Works great.

I too am a D.I.N.K., but the wife just fininshed Med School so my EFIS panel is on hold for a few years!
 
Prop wrench

Avery has a crow's foot adapter for $49, part #3528, that has 1/2" drive and fits 3/4" nuts on Hartzell props on O-360 engines. Someone have a cheaper source for same size crow's foot? Thanks...
 
Say, where did you have this done? I'd like to do the same.
Does the use of the crow foot throw off the torque setting, or do you keep using the same setting as with a socket?

TIA!--

I use these guys: http://www.teamtorque.com There is lots of information on their website. I used them for years and been very satisfied with their service.

The other guys have already addressed your question regarding the use of a crow foot...
 
Awesome wrench

Scott - nice wrench you've got there. I'll be giving you a call before my first flight. It will be out of GTU - hopefully in August.
 
I know an A&P who's been one for over 50 years that's never owned a torque wrench...

How does one properly build an engine without a torque wrench? Even if a person develops the skill to accurately gauge torque by feel, surely this skill will degrade over time without periodic "recalibration" against a known torque. For the life of me I can't see any good reason for not using a torque wrench on something as high-stakes as an aircraft engine or prop.
 
I borrwed that exact same wrench from an A&P while he did an annual in my hangar...It is THE tool for doing the prop nuts, He packed up and went to work for Boeing 2 days after I gave it back to him...I could not get a good fit with a crows foot on my MT three blade....When the time comes to re torq or remove the prop I'll either buy one or modify a crowsfoot to work. He said it ran him almost $400 for the wrench and the open end wrenches for the wrench. Not sure how long ago that was though...it looked brand new and it had a calibration sticker on it from a local PMEL shop.
 
Check out Sears/Craftsman too

We have a wrench that's very similar from Sears/Craftsman. They offer wrenches in both 1/2 and 3/8 drive. The 3/8 wrench is $200 and is rated from 10 to 100 ft-lbs. The 1/2 inch wrench is $230 and handles from 20 to 200 ft-lbs. Both are electronic strain gage controlled wrenches.

Sears electronic torque wrench
 
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