ATARNarchive

constructing prod on repeating crossbows

7 posts2006live thread
rob
hello
this is my first time posting a question.i have made Chu-ko-nu/ chinese repeating crossbow but every time i have tried to make the prod it breaks as i try to string it.i made the prod of two 25mm x 10 mm bamboo strips.
is that alright or does a composite of sinew,horn and bamboo have to be used?
does the prod have to be steamed and bent in a form?

Thanks
Rob
Stephen Selby
A bit surprised that they break during stringing.

Did you know that the prods are not set parallel with the arrow trough? The tips of the prods have to point a 3-4 degrees upward. Also, the foremost strip is about 1.5mm longer than the second one, and so one.

Try making a thinner pair (say 5mm) and see how they work. Perhaps you'd be better off with more layers and each layer a bit thinner.
Jim Welch
In addition to Stephen advice about thickness, the length might also be a problem. They may be too short.
Stephen Selby
I hope this pic is useful.
rob
Thanks for pics.i think i just made the prods far too thick and short.I making thiner and longer ones they seem work much better

does it matter if they get alot of set ?
Stephen Selby
Set is probably not moch of a problem. On Arsilan's, I suggest a three-inch block set into the hole in the stock on the belly side of the prod to support the prod itself. The present arrangement look a bit severe.