I'm interested in building a traditional bow-lathe, specifically of the type still used in parts of North Africa, a few videos of which can be found on YouTube.
The problem is that I can't really figure out how the mechanism for moving the two centers closer together works, aside from it seeming to use wedges in some capacity.
If anyone has any information it would be greatly appreciated.
to further clarify what im talking about, i'll link some pictures and videos below.
these videos, both from Morocco, show these devices in action, and are rather impressive in my opinion, but the details of the lathe itself are somewhat obscured by chips and the turner's themselves. Here are some of the best close-up images ive been able to find of a similar lathes.
The wedges I was referring to can be seen in the last image, but this is a somewhat different design.