View Full Version : Change Gears

03-05-2002, 10:10 AM
I would be grateful if someone could give me information on the change gears for a 1947 9inch South Ben lath. From the Boston Gear catalog it look like a 16 diametrical pitch. But the pitch diameter is not the same as in the catalog.

Rich Stimpson
3950 N. River Rd.
Freeland, Mi. 48623

Herb W
03-05-2002, 11:02 AM

I believe the dp is 18 (I have a '49 9")

For your info - there's a southbend lathe group on yahoo www.groups.yahoo.com/group/southbendlathe/ (http://www.groups.yahoo.com/group/southbendlathe/)
Lots of info there, particularly for the 9" models.

Good Luck!

metal mite
03-07-2002, 11:31 AM
Maybe you're measuring the o.d?
It will be two pitches larger than the pitch diameter.
Example; A 16 tooth gear o.d. will measure the same dia as an 18 tooth gears pitch diameter.
Just a thought.
Hope you find what you're after.
Ebay frequently has dealers "parting out machined piece by piece"

Metal mite

03-07-2002, 11:37 PM
.. no. of teeth +2/pitch = o.d.


best wishes

Steven L Jones
03-09-2002, 10:24 PM
the number of teeth + 2 ,divided by the pitch= the outside diameter of the gear blank