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Open end torque wrench / spanner

Question for the fellow mechs and gearheads – normal torque wrenches everywhere, but where can I find an open end torque spanner with interchangeable (imperial) bits? Something like this: http://www.amazon.com/Quality-Wrench-Adjustable-Torque-Spanner/dp/B010HE6O12/ref=sr_1_20?ie=UTF8&qid=1438706348&sr=8-20&keywords=torque+spanner+set ?

They are called ’Crow’s foot’ wrenches and are quite widely available.

One thing to remember is that the torque calibration will only be correct when the Crow’s foot is at 90° to the handle. Otherwise you need to apply a correction for the ratio of lengths from the hand grip to the torque head over the distance to the bolt centre (those distances are the same at 90°).

KHWD- Hayward California; EGTN Enstone Oxfordshire, United States

Or just use a ordinary combination wrench with the round socket on the torque wrench.

ENVA ENOP ENMO, Norway

That combo won’t work – i need to tighten a nut that has a pipe going through the middle.

Mark_1 wrote:

They are called ’Crow’s foot’ wrenches and are quite widely available.

+1

FAA A&P/IA
LFPN

Spend some time in a shop and notice how little use they make of torque wrenches… If it’s difficult to reach, get a feel for the torque somewhere else and do it that way.

AC43.13 chapter 7 discusses how to correctly torque with an extension – http://www.faa.gov/documentLibrary/media/Advisory_Circular/Chapter_07.pdf

For flared pipe fittings, there is an official torque, but it is much less critical than in load bearing structure as the requirement is just a good seal between the pipe flare and the 100° cone surface on the fitting. I would usually apply a little gasket compound to the thread and tighten to a ‘snug’ fit i.e. one finger pressure on the end of the spanner.
If you’re fitting a Hartzell prop to an engine, then you will need a crow’s foot and an accurate torque wrench.

This is a good guide – http://www.vansaircraft.com/pdf/Torque_Spec_Aluminum_Fittings.pdf

Last Edited by Mark_1 at 04 Aug 18:37
KHWD- Hayward California; EGTN Enstone Oxfordshire, United States

Shorrick_Mk2 wrote:

That combo won’t work – i need to tighten a nut that has a pipe going through the middle.

The round end on the torque wrench and the open end on the nut.

ENVA ENOP ENMO, Norway
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