Re: Lathe horizontal drive motor and pulleys

john kling

Thanks for the understanding of the probable motivation for the  design. I have an atlas lathe (also) that has V pulleys on both ends of the motor to counter shaft connection. The large pulley was damaged and I replaced it with a flat pulley of a logan (and it works). The motor on the atlas is on a hinge so shiffting step is relatively easy.

On Thursday, December 10, 2020, 11:55:24 AM EST, David R8 <davidwrate1@...> wrote:

I have a 1975 SB10K with the original countershaft system and guard. It has a two step v-groove motor pulley, flat countershaft pulley and cone pulleys. 
I think part of the reason for the flat countershaft is ease of changing v-belt positions because it is a royal pain in the behind to loosen the motor mount to release belt tension.
But with the flat countershaft, the belt can be eased off the side of the countershaft and moved without releasing the tension.

On Dec 10, 2020, at 8:42 AM, john kling via <jkling222@...> wrote:

The manufacture's decision to have a v belt run (on one side) on a large flat  pulley is counter intuitive. Several other manufactures also used this set up. When i noticed that a new to me SB had this set up. I assumed it was a previous owners set up/ mistake. Perhaps a large v pulley  was expansion or increases friction from the side of the belt.

On Thursday, December 10, 2020, 11:34:37 AM EST, E A <b-arch@...> wrote:

Now if I could only find one of those flat countershaft pulleys, I'd be in like Flynn.
Erik A

From: <> on behalf of comstock_friend <jfriend314@...>
Sent: Wednesday, December 9, 2020 10:55 PM
To: <>
Subject: Re: [SouthBendLathe] Lathe horizontal drive motor and pulleys
Here are the South Bend Forms for the belts and pulleys, and the horizontal and underdrive for 9" and 10K lathes. Also the speed chard from my HTRAL.

Note that while the motor pulleys are V-pulleys, the countershaft is flat. The V-Belt runs on it perfectly.


Join to automatically receive all group messages.