cutting inside teeth

how are inside teeth cut in a ring or annular gear? the only way i could think would be a shaper. clearly a hob or involute cutter are not going to work on an inside surface.

viktor

Reply to
vmpolesov
Loading thread data ...

or a broach, or an EDM wire-cutter.

I can imagine, too, a modified version of a chainsaw...

and, if the teeth are spiral cut, and the gear relatively large, a hob could do it, too.

I think the most commonly found ring gear is simply stamped from sheet metal (in the Boston gear company's old flagship product, the Boston KS pencil sharpener).

Reply to
whit3rd

Sure they are. You just work on the other side of the hob.

Gunner

"A prudent man foresees the difficulties ahead and prepares for them; the simpleton goes blindly on and suffers the consequences."

- Proverbs 22:3

Reply to
Gunner

Reply to
David Billington

snipped-for-privacy@gmail.com wrote in news:1159076090.013587.123480 @i42g2000cwa.googlegroups.com:

With a gear shaper. It uses a circular form cutter that rotates synchronous to the rotation of the work. The cutter is an involute form tool.

Other than that, it works pretty much like a conventional shaper in that it shaves rather than mills the material away.

The cutters are ground on special grinders. The grinding wheel, which is quite large in diameter and fairly thin, is dressed to an involute form. The cutter moves cross wise to the wheel and as it does it rolls so that the wheel grinds one flank, the bottom of the form, then the other flank. It rolls back to the start point then indexes to the next tooth.

On a CNC grinder it take about an hour to sharpen a cutter. On a mechanical machine it takes closer to four hours.

So the cutters aren't cheap and neither is resharpening.

Reply to
D Murphy

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.