Torque wrench calibration

[ThunderGuts]

Strictly this isn't bikes (although does relate to bike applications too), but plenty of folk I trust to know what they're talking about (unlike some forums full of amrchair mechanics). I was working on my van over the weekend and this required breaking out the "big" torque wrench, which is also a rather budget Draper one. Big(ish) torque figures were being called for which got me thinking about the calibration of that wrench. Is there anything fundamentally wrong with buying some £20 hanging scales (or a digital version, seems even cheaper - could check calibration using a measured amount of water) off Amazon, sticking the socket into some aluminium grips in the vice and using a bit of maths and pull on it with the hanging scales to calibrate it? It's not a precision tool, but 10% out is quite a big torque difference where we're talking close to 200Nm applications! Or should I just find a company that does calibration and throw my torque wrenches at them?

Ta.
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TG.

[stinkwheel]

I'll save you some money. I've done it before using a live load. Remember water weighs 1kg/litre and because it is not particularly dense, a small error in your volume measurement isn't a big percentage error. Especially with a big load.

So wrench in a vice paralell to the ground, bucket on string attached. If your string is 50cm out, add water until it clicks and divide the number of litres by two to get the weight you just applied.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Confusion]

[A100man]

Torque wrrenches are for important item s like head-studs and flywheel nuts - anything else should be done by feel (small stuff) or grunt (big stuff).

I fitted a towbar yesterday - instruction said 200Nm - on M12 bolts - I just did them up 'kin tight.
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Now: A100, GT250A, XJ598, FZ750

Then: Fizz, RS200, KL250, XJ550, Laverda Alpina, XJ600, FZS600

[ThunderGuts]

Thanks all

[stinkwheel]

I have a policy of only putting wheel nuts on with the tool I might have to take them off again with at the side of the road.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Polarbear]

[Nobby the Bastard]

In the space where a wheel would fit in my car is a can of tyre sealent and an electric pump.
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trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

[Kawasaki Jimbo]

[Nobby the Bastard]

I has RAC card as well.

The car didn't come with a spare wheel and the sealant and pump is standard fitment from the maufacturer.

Plus I have mushrooms for fixing tyres.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

[Kawasaki Jimbo]

[Nobby the Bastard]

The mushrooms do live with the bike on account of the fact that I've had truck drivers stop and ask me if they can fill my tyre with air, which is pointless if I can't fix the leak, but the first time I ever used one was on the car.
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trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Triumph Sprint ST 1050

[ThunderGuts]

We are frequently out in remote mountain areas with no reception; I really dislike the idea of total reliance on a breakdown service when mobile reception is patchy (it would be bad enough on a nice day, horrendous in bad weather). Pre-having a kid with me, probably would be less precious about it, but these days I am particularly keen to be self sufficient.

I shall do a basic calibration check using a weight.
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TG.

[blurredman]

[ThunderGuts]

To be fair, I've never had an issue with a wheel nut/bolt seized on, but wheels onto the spigots . . . oh yes (this is what I was doing at the weekend, removing, cleaning up and applying anti-seize).
____________________
TG.

[stinkwheel]

[A100man]

[ThunderGuts]

[The Artist]

For wheel nuts, I have been using torque sticks for the past few years. They are surprisingly accurate but I wouldn't use them on anything more critical.

No calibration required though.

[recman]

I use multiple wrenches of various types at work, one of which is pretty sophisticated and does things I don't pretend to fully understand.
Anyway, all of this means they are regularly calibrated.
There always seems to be extra wrenches to check on those days.

[Kawasaki Jimbo]

[Freddyfruitba...]

[blurredman]

Remember if you do have a full sized spare wheel, to cycle it through the car's mileage. You don't want to find after having a flat that your spare tyre is 30 years old and delaminates after 20 miles anyway... Yes, It might look a bit silly to have an odd wheel on the corner of your car for a year or two, but who cares.
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CBT: 12/06/10, Theory: 22/09/10, Module 1: 09/11/10, Module 2: 19/01/11
Past: 1991 Honda CG125BR-J, 1992 (1980) Honda XL125S, 1996 Kawasaki GPZ500S, 1979 MZ TS150.
Current: 1973 MZ ES250/2 - 17k, 1979 Suzuki TS185ER - 10k, 1981 Honda CX500B - 91k, 1987 MZ ETZ250 (295cc) - 39k, 1989 MZ ETZ251 - 50k.

[recman]

[ThunderGuts]