Re: Buying or CNCing some odd angle bevel gears. I'm stuck !!

--- In CAD_CAM_EDM_DRO@y..., "kaynrc" <tom.kay@n...> wrote:

> Hi guys. I was going to just ask where I might find some 22.5
>degree
> bevel gears, so that the shafts would intersect at 45 degrees, not
> the usual 90. I would by FAR prefer to buy them, but, this is a Cad-
> Cam group, so I'll also ask what you'd do if they can't be found.
>IE:
> Make them with a 3 or 4 axis cnc mill?

Contary to some of the posts on this list they can me made quite
easily IF you modify the design slightly.
It's also possible to mill normal bevel gears but they do need to be
hand finished afterwards. Could be fiddly on something this small.
They can be made manually on a vertical mill but even easier if you
have a 4 axis CNC.
I have made these in both forms so I know it can be done.
Email me off list for more info.
In case Yahoo chops the return address it's
machines [at] ntlworld.com

John S.

>
> Here's the application: I'm doing a little 1/4 scale Merlin, and
> there's a vertical shaft in the back of the engine, in the

wheelcase

> to be exact, and this drives a few items. The top of this shaft has

a

> gear which drives 2 other gears on the end of their own shafts.

These

> second shafts travel up to the rear end of the cylinder heads to
> drive the camshafts.
>
> If that sounds confusing I'll paint the simplest picture possible.
> The bottom shaft is like the bottom of a letter "Y" and the upper
> shafts, like the top part of a "y", are driven by it. The gears, of
> course, are in the middle of this acting as "glue" between the 3
> shafts. The top two shafts seem to be 90 degrees to each other, so

45

> degrees to the vertical driving shaft.
>
> The gears will have to be small, something like 5/8ths to 7/8ths

OD,

> so these are not easy to find items. The driving gear is smaller

than

> the 2 driven gears, and I will get around to counting the teeth on
> the Merlin wheelcase that I have in my basement. Can anyone suggest
> any possible source for these odd angle small bevel gears ???
>
> Ok, in keeping with the whole reason for the group, let's say I

have

> to make them, and that within a reasonable time I'll have 3 or 4

axes

> of cnc power at my disposal. I'm still finishing up Dan Mauch's 5

amp

> drivers, but they are essentially ready to go. Does anyone have
> software/methods/ideas on how to cut bevel gears that are designed

to

> intersect at 45 degrees, not the standard 90?
>
> Thanks as always, Tom Kay, Ottawa Canuckville.