I need to take a belt to this lathe

[Liljoebrshooter]

I have been using a single belt on my 13×40 lathe for years after having the same issues as you describe. I have never had any problems. Makes life a little easier.
Joe

 

[Shotgun]

The late models of the Atlas 12" did not all use the same belts. The bench models with a 4-speed conical pulley on the spindle use two different 1/2" nominal section FHP v-belts. The cabinet models used a total of four V-belts. The motor belt and the belt that connects the two 4-step cone pulleys are still 1/2" section FHP belts. The two identical spindle belts are "A" section A42 "Multiple V-Belt" belts, not 1/2" section FHP Belts.

Like I said, @wa5cab, the PO modified the setup. The two belts dropped straight down from the pulleys on the spindle to the pulleys on the motor. I don't have all the pulleys and bearing blocks to make it original. So, instead, I'm going to replace just one of the belts with the best gripping AX belt I can find.

 

[wa5cab]

Well, I would strongly recommend that you acquire the parts and put it all back to stock. Unfortunately, I don't have extras of the necessary parts to do that as the only late 12" that I ever parted out was a bench model, not cabinet.