chain help!

[Richie]

Originally Posted by timwilky

Whoa there numbers mate. This guy has a curvey, not one of your ugly pointy things


You have just told him to either strip the axle thread or severly dent his swinging arm. 65Nm is the recommended torque

Sorry didn't pick up on that part. it's 100Nm for a Pointy.

Originally Posted by timwilky

Hmmm puts to the test

13.5 stone = 189lb = 85.7kg

10" = 0.254m


Long time since I did any of this....
gravity 9.81 ms-²

85.7 *9.81* 0.254 = 213.54Nm

Whoops over tourqing again.

I guess Pete needs to stand about 5inch from the nut

I've got big feet so It will be about 5 inches from the nut...
plus I'm a tank mec, we like things tight...

[Stu]

Originally Posted by timwilky

Hmmm puts to the test

13.5 stone = 189lb = 85.7kg

10" = 0.254m


Long time since I did any of this....
gravity 9.81 ms-²

85.7 *9.81* 0.254 = 213.54Nm

Whoops over torquing again.

I guess Pete needs to stand about 5inch from the nut

So how does friction enter into this because I reckon if you torqued the nut properly up to 100 NM (which I would describe as damn tight) I can't imagine it would turn any more in the above scenario as long as he didn't jump on it.

[Richie]

when I put my rear wheel back on the bike I'm gonna try a little experiment.....
first stand on a 10" spanner at 5inches from the centre of the nut. mark the nut to the swinging arm, then stand on it with my 14.5 stone at the end of the spanner, mark it again, then slacken it and re-torque it to 100Nm with a in Callabration Torque wrench,
then well see what part friction plays...
All I know is when I stood on the nut to tighten it last time, then torqued it up I got atleast 1/2 - 3/4 of a turn more on the nut.
will have to remember to do this.

[Stu]

Actually, friction shouldn't play any part in it, because that is the only thing the torque is acting against. Just can't get my head round it that Richies scientific method sounds like it should be rightish.

Can I advise you to torque it first, mark, loosen then stand then you'll see that you're about to strip the threads

Friction plays a large part in torquing up a bolt.

On our chemical plant all torque measurements are given for greased bolts, done dry it is plain not enough and more is required.

Hence lots of swearing at sloppy fitters not greasing up bolts, then painting them with grease afterwards, must have cost the contracting firm a good £35k in our last shutdown in man hours alone remaking joints.

[Richie]

Right got the wheel on and tried the manual way (foot on spanner) and the tecnical way, using the Torque wrench....
and the verdict is...

I'll let WRC63 tell you the findings...

[timwilky]

I can guess...... Too many pies?

[Richie]

Originally Posted by timwilky

I can guess...... Too many pies?

you'll see...

Originally Posted by Richie

you'll see...

Aim:
Determine torque setting in Nm of a nut tightened using a spanner and human technique.

Method:
Using our 22mm "killing spanner", of about 11 inches total length tip-to-tip, and my weight (about 12.5 stone without clothes and shoes), we used the 'stand on spanner then bounce once' tightening method to do up the axle nut.

We then utilised the 'Fisher Price British Army My First Accurately Calibrated Torque Wrench' to tighten the bolt further - except it clicked on first pressure, so the nut was already at 100Nm or above.

Reversing the wrench with torque setting still at 100Nm allowed us to undo the nut without a problem, suggesting that the manual method had allowed us to torque the nut up relatively accurately.

Undoing the nut and torquing it with the wrench to 100Nm, I then stood on the spanner, which would not turn at all, until I bounced heavily upon it.

Conclusion:
11 inch spanner plus human of 12ish stones in weight allows tightening of SV K3-> axle nut with acceptable accuracy to 100Nm without use of a torque wrench.

This is just plain SAD