Hi all, I need a bit of help with some worm wheels I am trying to cut.
The gear blanks are 1/2" aluminium and the worm I have made from 20mm x 1.5 threaded bar.
I have attached a couple of pictures of the setup. The lathe I am using is a 1940's Winfield MK3 so its very basic. I slotted the worm hob and then heated and quenched it to harden it.
The problem I have got is that after 4 hours of running the lathe I have only got 0.4mm into the blank. The teeth it has put into the blank feel raised rather than cut like it has pushed its way in rather than cut its way in.
I have been very carefull only advance the cross slide a little at a time but I would have thought after 4 hours of hobbing I would have got further in.
I was not sure wether me anodizing the gear blanks before cutting the teeth might be the problem but surely the hob will remove an anodized coating.
Any tips on making a good worm hob and hardening it? how hot etc? how should the slots be cut into it, at an angle/straight? and what speed should I run the lathe at? I have searched google for the answers but I really need help from somebody with experience.
I have uploaded a video of the cutting in action after about 1 hour of running the lathe.
Gear Cutting - YouTube
Thanks for your time
Ceefna
The gear blanks are 1/2" aluminium and the worm I have made from 20mm x 1.5 threaded bar.
I have attached a couple of pictures of the setup. The lathe I am using is a 1940's Winfield MK3 so its very basic. I slotted the worm hob and then heated and quenched it to harden it.
The problem I have got is that after 4 hours of running the lathe I have only got 0.4mm into the blank. The teeth it has put into the blank feel raised rather than cut like it has pushed its way in rather than cut its way in.
I have been very carefull only advance the cross slide a little at a time but I would have thought after 4 hours of hobbing I would have got further in.
I was not sure wether me anodizing the gear blanks before cutting the teeth might be the problem but surely the hob will remove an anodized coating.
Any tips on making a good worm hob and hardening it? how hot etc? how should the slots be cut into it, at an angle/straight? and what speed should I run the lathe at? I have searched google for the answers but I really need help from somebody with experience.
I have uploaded a video of the cutting in action after about 1 hour of running the lathe.
Gear Cutting - YouTube
Thanks for your time
Ceefna