Shopsmith Forums

When is the right time to replace the drive belts on a Mark V? Obviously if the belt breaks but what about less obvious failure? Is is suggested to replace both? Which belt is most likely to need replacing? I have been having some grabbing and slipping issued using the lathe, a lot of which has to do with my beginners heavy hand. I pulled the belt cover off and noticed that the flat belt had a half an inch+ of defection so I snugged it up a bit via the eccentric. I am not sure which belt 'slips' nor which, if either, needs to be replaced.
Any suggestions?
Thanks for your time.

basaltboy wrote:When is the right time to replace the drive belts on a Mark V? Obviously if the belt breaks but what about less obvious failure? Is is suggested to replace both? Which belt is most likely to need replacing? I have been having some grabbing and slipping issued using the lathe, a lot of which has to do with my beginners heavy hand. I pulled the belt cover off and noticed that the flat belt had a half an inch+ of defection so I snugged it up a bit via the eccentric. I am not sure which belt 'slips' nor which, if either, needs to be replaced.
Any suggestions?
Thanks for your time.

Since you need to slide the belt cover away from the headstock to lubricate the motor shaft (floating sheave) at least once a year (more is better, Shopsmith recommends every 10 hours), I recommend checking for any loose threads, chunks missing or frayed edges on either belt and/or cracks on the inside (bottom) of the V-belt. I only replace defective belts if found for my personal headstocks. I spray belt conditioner on each belt after inspection at this time to prevent drying, cracking, fraying, etc. I also spray the black bandsaw tires at this time. I recommend checking the Poly-V or Gilmer belt tension (1/4"-1/8" deflection) at this time and adjusting if needed.

Otherwise, it does not hurt to have a spare set of belts on hand. I turn each new belt inside out when storing them to prevent each belt from taking a set over time. I spray them with belt conditioner when storing them.

Thank you Bill.
Gives me a real good idea of how to proceed.
--pat

billmayo wrote:Since you need to slide the belt cover away from the headstock to lubricate the motor shaft (floating sheave) at least once a year (more is better, Shopsmith recommends every 10 hours), I recommend checking for any loose threads, chunks missing or frayed edges on either belt and/or cracks on the inside (bottom) of the V-belt. I only replace defective belts if found for my personal headstocks. I spray belt conditioner on each belt after inspection at this time to prevent drying, cracking, fraying, etc. I also spray the black bandsaw tires at this time. I recommend checking the Poly-V or Gilmer belt tension (1/4"-1/8" deflection) at this time and adjusting if needed.

Otherwise, it does not hurt to have a spare set of belts on hand. I turn each new belt inside out when storing them to prevent each belt from taking a set over time. I spray them with belt conditioner when storing them.

Any favorite brand of conditioner?

burkhome wrote:Any favorite brand of conditioner?

No, I buy it at any auto parts store and use several cans each year.

do you have to remove the belt to spray it on - in regards to Shopsmith?

mgdesigns wrote:do you have to remove the belt to spray it on - in regards to Shopsmith?

NO, I apply the belt conditioner on any belt (auto or machine) I have. I normally use the sanding disk to rotate the quill while spraying each belt. If I am already dirty or doing a quick fix for a slipping belt, I use the extension tube with the belt conditioner can and spray each belt while operating at the slowest speed. Operating the headstock while spraying each belt can make a mess of anything close by that end of the headstock. I spray my belts before storing them inside out too.

I have used belt conditioner for 50+ years now. I worked a night job as a used car mechanic back in the 50s where I learned how to extend the life of many cars, trucks and farm equipment. I am a firm believer in belt conditioner, LPS Force-842 Dry Moly Lubricant and Kroil as I use many cans of each one every year.