Spoke Threading Question???
 

I've been lucky enough to find a large quantity of 14 gauge stainless steel plain spokes in 305mm length at a very reasonable cost, with nipples included. Don't you love e-bay sometimes?

I'll be using some so I can rebuild an old pair of wheels - perfect size. There are enough spokes left to rebuild my other wheels that are awaiting a refurb, but the spokes are too long - I need about 290mm. If I could extend the threading up the spokes I could use them and cut off the excess after building the wheels. I know that professional spoke threading machines roll the threads onto the spokes from outside.

My question is - is it feasible to use a tiny die to cut this thread,in the same way as you use a tap and die set to thread nuts and bolts? I have some small dies but nothing that small. Does anyone know what the thread size and pitch is on this gauge spoke and if it's possible to buy a die in this size (maybe a model-maker's tool??)

I'm trying to do this as cheaply as possible so although it would be easier to a) buy the right length spokes or b) pay my LBS to extend the threading and cut the spokes or c) buy a spoke rolling machine and do it myself, all of these options are not feasible in my current pecuniary situation.

All positive replies gratefully received!

Thanks,

No, Threads on Spokes are rolled, not die cut. Find a local LBS that has a Phil Wood Spoke machine to cut them for you (probably a small charge). You could do it with a hozan spoke machine also but that is a time consuming process assuming you could find the hozan threader. Or purchase new spokes. There was a guy on eBay selling 75, 2.0, SS straight gauge, custom cut, for around $23.

Just to be clear. As you know, spokes have rolled threads, and in answer to your question you cannot cut new threads, and must roll them.

The reason is rolling forms threads with a crest diameter larger than the blank. Rolling doesn't remove material but, flows it from the valley to form the peak, so the diameter of the blank is equal to the mid-line between the crests and root of the thread, whereas cut threads have a crest diameter equal to the blank they cut into, and a root diameter smaller than that of the rolled thread.

If you can't imagine the difference imagine two different people digging V-shaped trenches to create a thread-like profile. The first person cuts into the ground and carts away the dirt, making threads with tops at ground level, and bottoms at the desired depth.

The second (smarter) person doesn't want to work so hard, so he only cuts half as deep and piles the dirt between his trenches, making small V-shaped ridges in line with the trenches. The total height of his profile is the same as the first, but he's cut only half as deep, and raised the level of the soil, by the other half.

A hack job isn't worth it...

...just head to an LBS with a Phil Wood spoke machine and get it done quick and cheap.

=8-)

Thanks everyone, I've learned a lot from your replies. Although I knew the threads were rolled, not die cut I never appreciated why. Now you've explained, it all makes perfect sense! Thanks for your patience with a bewildered old duffer.
Ironically I had the chance to buy an old spoke rolling and cutting machine some months ago but it seemed a bit expensive for a worn piece of kit and I didn't think I'd ever need one. I'll see if I can contact the guy who bought it and see if he can help me out or even lend it to me for a day. Most of the LBS's left in business around here don't even build wheels, just try to sell new wheels from a catalogue or persuade you to buy a new bike. One offered to order me new spokes at £2.00 Sterling per spoke plus 55 pence per nipple - probably about $4 each! This makes adapting my cheap ones worth while. However there are one or two 'real' bike shops in outlying villages that might be worth a phone call.........
Once again, thanks for your help!

: O