Originally Posted by erase42  I make ropes in foam, anyone interested? probably not  |
yeah i'm interested - how'd you do it? I can see in the photo the profile of the waste stock - did you do this via hot wire? how do you set up a rigid hot wire (i know how the tension ones work)?
you can achieve what you want only be by either mechanically linking the x motion to the spindle or controlling their relative positions electronically. I'll assume its a wood lathe, so you have no motion along either axis. if its metal, its easy, is already indexed although you will have to play/change the gear ratios to get enough helix.
you'd have to build ways along which router would travel. cnc would be good, you'd have to have an encoder on the spindle though. with a second axis (depth) you could do all kinds if fluting. But just for rope, a mechanical method struck me. either way you have to devise a simple way for the router to move along (a pipes and skate bearing & plywood rig for example).
the mechanical idea is to connect the spindle to the router via a light steel cable. The cable wraps around a wheel on the outboard side of the spindle, changes direction 90 degrees via a pulley and then connects to the router carriage. The dia of the wheel would determine the feed rate. you could 'block and tackle' it to create lower feed rates and/or change the dia of the wheel. if you do so, cut the power at the breaker so you don't flip on the power by rote and send the rotor through the wall or worse