Shaft end drive dog

The drive dogs of this type that I have seen have identical geometries for the tooth and the space. Making a five tooth dog would be accomplished by dividing the circle into ten equal sectors with 36º included angles. .This will make both dogs identical and provide the greatest strength.

On the other hand, a Lovejoy flexible coupling uses an elastomeric spider with six legs with parallel sides.

The illustration on the left below would be for a five tooth dog driving an identical dog. The right illustration would be for a Lovejoy type dog using the s[pider below and driving an identical dog.
Dogs.JPG
 
The beauty of the 5 tooth dog clutch is that it is cut in only 5 cuts, going all the way across with a single cutter, set radially on its edge.
 
I think benmychree is right. Center your end mill on the hole. Offset the table by the radius of the endmill. 5 cuts is all that is required.
 
I think benmychree is right. Center your end mill on the hole. Offset the table by the radius of the endmill. 5 cuts is all that is required.
Yes correct i did the same practice when i made these but only did 3 cuts IMG-20190530-WA0002.jpg
 
I've made a few of these, (actually in the last century) I don't think 5 cuts will do it, but ten will. Start with a two flute cutterthat will go through the gap between 'teeth', center the piece on the endmill and offset it the radius of the end mill. Cut all the way across, rotate 72º and repeat four times. Then youve got to reset your cutter and do it again, but I can't remember just how to reset it.
 
When I 1st saw that comment, I thought really. But upon further thought and examination, that is correct! Except maybe for clearance if needed.
Thanks
Aaron
 
The technique will actually work for any dog with an odd number of teeth.
 
Back
Top