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john.b.watts
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VBMWMO #8877
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My R69 is ready for the swing arm reassembly of the drive shaft bell-to-taper (1:5) nut but I do not have a torque wrench that handles 100 ft/lb torque applications. I have a solid bar 1/2" and a long piece of pipe, but I am thinking that combo. is too imprecise. Should I seek out a shop to do this correctly or does anyone have a solution I might employ? I have a pretty well-stocked shop, but just nothing along that type of torque wrench (but might soon?).

Thanks - John

The Plunger
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A fairly simple math problem.

A fairly simple math problem. Here's a solution. It's a calculator to see how much extension to use on your wrench, easy peasy.
https://www.belknaptools.com/support-library/extensions-calculator/

I'll clarify: If your wrench only goes up to(indictates) 50 ft/pds and is 12" long from the center of the socket to the center of the handle then simply double the handle length to 24" to get 100 ft/pds (still 50 indicated) .

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Brian
'52 R67/2, '53 R51/3

miller6997
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You sure?

An engineer friend disagrees with your calculation. He says the dial reading still reflects the actual force being applied to the nut.

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Jon Miller
'67 R69S
'13 F800GT

schrader7032
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San Antonio, TX
Joined: 10/27/2006
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No, the dial reflects the

No, the dial reflects the reading at the socket end of the wrench. The dial doesn't know how many inches/feet/miles of an extension you have. Torque is force times distance and the dial is reading the amount of force you're putting in relative to the end of the torque wrench.

A simple example. If you have a 10 lb force applied at the end of a 10 inch torque wrench, the force will be 100 in-lbs and the dial will indicate that. If you add an extension (inline with the body of the torque wrench) of another 10 inches and use the same 10 lb force, the dial will still read 100 in-lbs but the actual torque will be 200 in-lbs.

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

312Icarus
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100 ft. Lbs... put a 2’

100 ft. Lbs... put a 2’ extension on a wrench and pull really hard! Guess how hard by imagining picking up a 50# sack of cement with one arm and you will be close enough!

Just my opinion.

Icarus

808Airhead
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SEARS has tq. wrench for

SEARS has tq. wrench for 50-70 dollars that can handle that tq. IIRC I did mine to 70-80 ft. lbs.

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Thomas M.
R69s - R60/2 - R67/2 - R51/3

Daves79x
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Just Make

Just make it as absolutely tight as you can get it.

Dave

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Dave

brownbmw
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So. Cal.
Joined: 01/03/2009
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The discussions above RE:

The discussions above RE: extensions to a torque wrench don't make sense. If the torque value changes depending on length of handle then it would also apply various values depending on exactly where you hold the handle - an inch or two up or down would give a different torque reading. This is simply not the case, as that would defeat the accuracy of a torque wrench. Extending the handle gives the user more leverage but it does not change the reading on the wrench.

schrader7032
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San Antonio, TX
Joined: 10/27/2006
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How I hold the handle on my

How I hold the handle on my old Sear beam-type wrench does make a difference on the applied torque. My torque wrench has a "floating" handle...it has a central pivot and when use it, I must ensure that the handle does not touch forward or aft of the pivot. If it does touch, then the effective distance of the applied force does change. In the end, it's probably not much of a change, but I'm conscious of this feature and endeavor to keep the handle from touch and have the handle "float" on the pivot pin.

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

bstratton
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That won't work

brownbmw wrote:

The discussions above RE: extensions to a torque wrench don't make sense. If the torque value changes depending on length of handle then it would also apply various values depending on exactly where you hold the handle - an inch or two up or down would give a different torque reading. This is simply not the case, as that would defeat the accuracy of a torque wrench. Extending the handle gives the user more leverage but it does not change the reading on the wrench.

Correct. My torque wrench will click at the torque I set it for. Extending the handle means it will require less force on the end of the handle but it will still be accurate. The only way to get an accurate indication of torque on the socket is to get a wrench that is capable of reading that much torque. I have a similar problem with my boat. The keel bolts need to be torqued to 275 lbs. I'm sure I can give myself the leverage to get there but since my torque maxes out at 100 lbs I have no way to be sure. That requires a 3/4 inch drive torque wrench that costs upwards of $600. I wish I could put a pipe on my torque wrench and save that money.

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Bstratton
1971 R60/5
1965 R50/2 (project)
MA

brownbmw
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So. Cal.
Joined: 01/03/2009
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Set your torque wrench to 90

Set your torque wrench to 90 lbs/ft and torque the keel bolts 3 times. Makes as much sense as a longer handle and gets the same result.

Littlemicrocars
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tool for torque

Call your local auto parts store ,,, they will loan one out to you.. with a deposit.... easy as pie...Leo

540964
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VBMWMO #7445
Milford Michigan
Joined: 08/16/2008
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Torquing fasteners

Copied from:
https://www.thesamba.com/vw/forum/viewtopic.php?t=534256&start=0

Here's what I do:
Get my breaker bar and big socket.
You need 250 ft. lbs. of force so that is 250 lbs. at 1 foot out from the socket.
1 foot = 12 inches.

Say you weigh 175.
So take 250/175 = 1.43
12 inches x 1.43 = 17.1 inches.
Mark a line on the bar at 17.1 inches.
Get someone to hold the engine, I usually have my wife put her foot on the opposite cylinder head with the engine on the ground.
Stand on the bar with all your body weight at the line you just made. I usually have to brace myself on my car or put a hand on a nearby tool chest.
When the bar stops moving downward from your weight, you just applied 250 lbs.

Don't jump on the bar or you will over tighten it.
It takes less force than you think.

I use this method to do the rear axle nuts too.

I used this method to torque rear axle nuts on my Porsche 911.
Have fun.

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