Re: Making Stepper Pulleys

Hi Richard,

If you've made a hob for XL timing belt pulleys, you're ahead of me!
I'm also searching for enlightenment! Can you share your hob design?
I've heard that a 1/4" tool blank cut to profile can be used in a fly
cutter (or something similar, at the proper angle).

The "fiddling" is what Bill (and I) are trying to avoid.

Alan KM6VV


phrh@... wrote:

>
> --- In CAD_CAM_EDM_DRO@y..., Alan Marconett KM6VV <KM6VV@a...> wrote:
> > Can ya make me an XL 037 cutter?
>
> I used the data from Stock Drive catalog for making a hob for XL
> timing pulleys. Even made some nice pulleys using aluminum and the
> hob of course. There must be a secret "K" factor though because the
> blank OD given does not work for many of the pulley OD's! It is close
> but requires some fiddling to get it just right. I have seen the same
> problem when making worm wheels using a tap as a hob unless I first
> cut nice gashes at the correct lead angles for the thread on the tap
> being used.
>
> The pitch of the XL is 0.200" (Rack). The tooth included angle is 50
> degrees. The depth is shown as 0.054" but this is one thing you will
> have to play with when using a hob!
>
> I hope some bright guy out there will enlighten me. Richard
>