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« on: 30 March 2017, 09:29:35 pm »
I have listened to what people have said on all sorts of different topics and I hope I have thought about it in a fair and open way, and of course have learned from some of them.
I have been convinced by different people’s ideas on different subjects and topics.
But just like everyone else, I tend to think that the way I have always done things is the right way, and I know that each and everyone of us is no different, hence all the heated discussion and debates on here and every other forum that you will ever go on, because we all think we are right.
Heated debate is not a bad thing, because just sometimes it manages to find the truth or the right or wrongs on what is being debated.I put forward to you my thoughts on torque settings (Boring! I hear some say) but if you think that, go put the kettle on and read no further.
But here we go, at the end of this you can say ‘I don’t believe it, or he’s talking like a prat, or ‘what a load of bollocks’ but do not just dismiss stuff because it is not the way you have always done things or thought about things, think about it and weigh up what is being said, if you then decide its not for you then that’s OK, at least you have thought about it.
You know what? there was a time when pretty much everyone thought that the world was flat and that if you sailed far enough you would fall off the edge, and then someone put forward the notion that in fact they though it was round and that it was not possible to fall off the edge, and the majority said ‘What a prick’
I have heard it said that lubricating nuts and bolts will give your false torque settings and it’s possible to over tighten and strip threads, or shear off bolt and screw heads if lubrication is applied.
Now, if you are winding up a nut and bolt that has lubrication applied, as tight as you think it should go using ordinary spanners relying on just touch or feel, then you may very well shear it off, because the passage of the nut on the bolt will be easy, with little resistance because of lack of friction (metal against metal)
Now If you apply the same lubricant to the same nut and bolt and tighten it up with a torque wrench to the recommended torque setting for that nut and bolt, your torque wrench will break away at the setting that you have set the torque wrench at, it will not over tighten it, or shear it, the problem comes when people feel that the nut and bolt seemed to tighten up very easily, because of lack of frictional/resistance because of the applied lube, so they then lay on the torque wrench passed the breakaway point and tighten it just a bit more, and maybe just one more tweak for good luck, because they don’t believe their torque wrench.
20Nm is 20Nm no matter how smooth or rough the passage of the fastener is, it is still 20 Nm.
In fact you will get a more accurate bite using lube because there is no dry resistance to overcome.
If for example you had a small nut and bolt with fine thread that was a bit rusty or a dirty thread and it was meant to tightened up to the torque of say 5 Nm. Because of the rust/grunge resistance of the none free running nut you could be applying 1 Nm to over come the resistance of corrosion or grunge in the threads (the non free running nut), then you will not get an accurate reading and the bolt will not be as tight as it should be, because 20% has stolen from your rotational resistance.
The way to get a fixing to the right torque is for it to be as free running as it is possible to get it and use a torque wrench. And don’t doubt your torque wrench; trust it.
Right! where’s that kettle.tommy.