Fillet radius on spur gears

[John Hartley]

I have my spur gears cut with EDM wire machining.  The machine follows the dxf profile.  The gears are used for power transmission, so I need a fillet radius at the base of the tooth.  I don't see a way of adding it and manually editing the dxf file is tedius. 

It would be very nice is there was a parameter where I could enter the desired fillet radius.

Thanks,

John

[ArtF]

John:

  Ive added this to my list and will look into allowing it as an option.

Thx
Art

[JustinO]

While you're at it...

The gears of old "Geometric Chucks" from 200 years ago have semicircular tooth bottoms. It gives them a unique and characteristic look. Maybe you could add a toggle for that....

[ArtF]

ahh, like the racks on the gta page. Ill add that to the list of
possible refinements as well.

Art

[JustinO]

I give up. GTA page? I found this page which happens to have round bottom gear teeth...
http://www.gtapartners.net/?page_id=14

But no sign of a rack.....

They  cropped the image, but it looks like these three gears on in mesh....oops.

Another amusing image is on the wikipedia "gear" page. The helical gears, show in parallel and crossed configuration....oops.


Thanks Art!

[Mooselake]

Geometric chucks, which I'd never heard of before, are really cool.  Thanks, Justin.

I found a simulator here but it's too late to download and try it.

Kirk

[JustinO]

Mooselake, put this word into the Google image search: guilloche

[BobL]

Justin;

I've been asked this question often offline, so to clairify, GTA (generalized toothing algorithm) tab in GM can only be found in developer version 4.80, lockdown version 4.67 does not.


Cheers
Bob  8)

[ArtF]

While a semicircular root can be put on gears above a certain tooth count, I dont think they'd work on a gear that requires
a trochoidal curve at root. Id suspect meshing problems. Ill look into whats possible though in the code I use to generate the curves.

Art

[Mooselake]

Mooselake, put this word into the Google image search: guilloche

Thanks, Justin.  I've only heard of Rose Engines, never a lathe add-on, and been unable to find a software rose engine simulator since the real thing is way beyond my hobby budget.  Hope to try the Geometric Engine simulator tonight.

Kirk