I've managed to break 2 of the brass square nuts (M8) in the track that hold the mast plate to board. I think I over tightened them. Since I have a torque wrench can anyone recommend a torque setting for brass nuts which are only a few mm thick? Also, I'm considering machining up a few stainless nuts since I assume they will be stronger - is this a good idea?

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KIT33R said..
I've managed to break 2 of the brass square nuts (M8) in the track that hold the mast plate to board. I think I over tightened them. Since I have a torque wrench can anyone recommend a torque setting for brass nuts which are only a few mm thick? Also, I'm considering machining up a few stainless nuts since I assume they will be stronger - is this a good idea?

Hi mate
I thought just firm tightness with Allen key.
Been using a small Bosch battery drill then a nip with Allen key .But the small drill is enough I reckon.

Dunno about brass screws, but bicycle torque wrenches go to 5nm so you don't crush the carbon. They're fairly cheap and you can pop in a standard 1/4" hex bit.

5nm is similar to the force of finger tips on a T-handle hex key.

I am now using a Ryobi battery screwdriver and it goes to 5nm too.

Why bother with a torque wrench just tighten by hand thats easily enough.
I've never seen anywhere on any advertising a recommended torque setting.

Golden rule for tightening bolts.
tighten till thread strips then back off a quarter turn.

but really. Now you know that what you did was too much , just do less.

maybe look for stainless instead of brass.

Thanks guys, I've made up some stainless nuts. See how they go. I think I was going too hard on the wrench.

Good idea, I had the same problem with the soft brass nuts giving way where the step/weak point is.
Switched them out and no problems... But I'm pretty hard on my gear and the amount of pressure that
I put them under.

It's been too long since I've sourced the brass slide nuts but the thing to look for is that the step Corner is not sharp but has a slight fillet.
you only need about 30% more thread length in brass to get back to the strength of stainless. And those stepped slide nuts achieve this easily.

if anyone has a source for these, I'd like to know.

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RAL INN said..
It's been too long since I've sourced the brass slide nuts but the thing to look for is that the step Corner is not sharp but has a slight fillet.
you only need about 30% more thread length in brass to get back to the strength of stainless. And those stepped slide nuts achieve this easily.

if anyone has a source for these, I'd like to know.

I broke 2 of the stepped ones. But they were old and a dubious history. They came off a Slingshot board. It's worth calling Kitepower, I know they are getting some spare nuts in soon. Also, Axis is supplying stainless nuts.

Make sure you use the right Allen key and go for a firm wrench tight. if