torque adjusting when installing DIN adapter

[falcos]

Hello all,

When installing the DIN adapter for my Titan, it was instructing me to use a calibrated torque wrench with a crow foot for the nut and tighten it to about 20 foot-lbs. The same went for the handwheel retainer - that was about 15 foot-lbs. I have all the necessary tools to do this, and will. I was just wondering if everyone actually abides by this and how important is this calibration?

Just curious.

Thanks.

 

[Genesis]

the reg body is brass, and reasonably easy to damage.

Too lose and it could come apart under pressure! Bad Karma!

 

[The Chairman]

you calculate the offset of your Crowsfoot. Not having the fastener centered under the axis of the rachet will introduce an additional moment arm. Some are close, others are not. I solved this issue by buying the proper socket and extension from Peterbuilt. No offset and so no calculating the torque multiplier.

Join URT (Use the Right Tool)!

 

[Genesis]

TYPICALLY have an internal hex and do not require a crows-foot - just a large enough 1/4" drive hex bit and the proper extensions/adapters to put on your torque wrench.

I have a cut-down socket for yoke nuts; the newer ones have a large enough screw to be able to remove it and put the socket extension through the hole, meaning I don't need a crow's foot for them either.

 

[The Chairman]

Neither of the DIN adapters for my Cousteaus have that hex on the insert! I am fairly sure his Titan uses the same adapter. But I like the fit and feel of the right tool for the job!

 

[redacted]

The offset can be ignored if the extensoin is put at a right angle to the length of the torque wrench. So let the crowfoot form an "L" on the torque wrench rather than orienting it srtaight off the end.

 

[Genesis]

All my SPs do, and quite a few others have no obvious other means of attaching them (no flats or such), and although I haven't taken them off personally, it appears there has to be a hex inside otherwise they'd not be removable at all

 

[The Chairman]

any time you increase the length of a moment arm, you are increasing the torque it generates. Even just an inch or two could cause enough extra torque to strip out those fine brass threads. It's a hard concept to grasp, but it is true nonetheless. As a way of understanding how leverage increases with length, grab your ratchet near it's head when trying to undo a fastener... it is tough. Now notice how your effort decreases and the resultant torque increases as you move your hand closer to the end of the handle. Now look at that crows foot... measure the distance between the center of the drive to the center of where the fastener would be. Thats the additional leverage (or moment arm) that would be realised by it.

 

[redacted]

That is, if you take an "extension" the same length as the torque wrench and use it to lengthen the arm, then you double the torque. But if you take that same extension and attach it so it comes back under the torque wrench, you get zero torque. And if you attach it at a right angle to the torque wrench, the torquing effect will be as set. Just to location changes. So if you attach the crowfoot at a right angle to your wrench and set it for 200 inch pounds, that is what you should get at the connector. But if you attach it so that it lengthens the wrench, then it increases the torque proportional to the length increase. That's how I'm measuring 240 in-lb with my 200 in-lb wrench.

 

[neil]

Awap,

It's probably very close to the same torque but not exactly.

Even at a right angle the moment arm is longer, although not as much as a straight attachment Here's the formula for an extension to a torque wrench.

T1=T2 x L1/L2
where:
T1 = torque setting (reading) of the wrench
T2 = actual torque applied (torque needed)
L1 = original length of wrench
L2 = extended length of wrench with crow's foot

If you put the crow's foot at a right angle, you still have (to be anal and URT) to measure from the wrench pivot point to the center of the crow's foot head. Aaah, it's close enough! Just tighten that sucker down. Use some purple Loctite (just kidding!).
Neil