Greetings. I brought home a 9A a few weeks ago and am getting it closer to start making chips. This lathe was supposedly rebuilt by someone the P O bought it from. It seems to be in pretty good shape but I have found and corrected some issues. I am trying to figure what my countershaft rpm is going to be as I have had to put a new motor on it. Motor speed is 1755. Pulley is 3.25". Flywheel is 11". It appears that someone adapted a swamp cooler pulley for the 11" flywheel. I see on the SB specs that the countershaft rpm should be 300. Sorry if this subject has been covered but I tried searching the forum and didn't come up with anything that helps me.
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Figuring Countershaft RPM on 9A
- Thread starter RVbeemer
- Start date
- Joined
- Sep 24, 2020
- Messages
- 1,922
You have an oversized pulley on the countershaft, the factory one is 10".
This will help with your calculations.
This will help with your calculations.
- Joined
- Apr 30, 2015
- Messages
- 11,381
3.25
/11 x 1755 = 518
The motor pulley could be smaller like 2" if you wanted closer to 300 rpm
/11 x 1755 = 518
The motor pulley could be smaller like 2" if you wanted closer to 300 rpm
Your assumption is correct!
- Joined
- Nov 15, 2020
- Messages
- 139
Here's a good reference if you want to know what these shipped with from the factory.
