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SDL
10-24-2009, 06:47 PM
Does anyone know a good site for entering the basics data for bevel gears and getting all the Dimensions.

I have tried the plug in in the Machinery handbook CD but, vertex distance at small end of tooth j is coming out bigger (1.25") than Vertex or apex distance J (0.6294)
this is for 8DP, 12 tooth pinion, 44 tooth gear.

Steve Larner

J Tiers
10-24-2009, 10:28 PM
No. I've been thinking of writing an article, since I have cut a bunch of bevels fairly recently, but I'm not nearly done. it's a big subject, and easy to propagate bad info. I don't know of a site that is really good. Lots of "noise" via google.

Why don't you lay it out yourself? The best bet for directly getting workable gears is to just find a gear cutter that is best fit to tooth profile about 2/3 of face back from the apex end of the tooth.

Then set up to cut on the pitch line angle, letting the rest of the tooth go hang. You'll get a good tooth except at apex end, if you do the side shift deal to get tooth thickness right and toothspace right. You file down the apex end a little where it is too thick.

oldtiffie
10-25-2009, 12:17 AM
I'd agree with JT.

Take it easy - and go back over your calculations.

Bevel gears cut with a standard tooth cutter - or any cut on a mill - are a "kludge" and a compromise at best.

But as JT says, with a bit of prudent use of some clear thinking, you will get a pretty satisfactory result.

.RC.
10-25-2009, 02:36 AM
Try here -->> http://www.amazon.com/Gears-Gear-Cutting-Ivan-Law/dp/0852429118

oldtiffie
10-25-2009, 03:18 AM
Yup Ringer - that item at your link will do for "shop" gears for medium accuracy and load and speed capacities - but it will work.

"Gears and Gear Cutting" (Ivan Law) - pages 104>111.

Next best is the "Machinery's Handbook" which requires a fair bit of math and tables etc.

John Stevenson
10-25-2009, 08:03 AM
Steve, PM me your email addy and I'll post some stuff on.
Don't bother with Ivan's book if you are doing what I call proper bevels as his method is for parallel depth bevels which are a different animal, easier to do but they have to run as pairs

.RC.
10-25-2009, 08:22 AM
This .pdf might be helpful, I scanned it out of an old book that was used for apprentices..

http://users.beagle.com.au/lathefan/Cutting%20a%20bevel%20gear.pdf