- Joined
- Jun 25, 2024
- Messages
- 1
I recently bought a Rockwell 21-100 vertical mill. It appears to be in good shape, I do not know the history of the mill.
The motor v-belt may be the original, see photo below. The belt was relatively easy to remove from the motor housing.
After reading about the v-belt on this site and others I purchased a 4L280 belt. There is no way this belt was going to fit my machine without complete disassembly. I tried removing the motor and loosening the cast aluminum motor housing but that did not provide enough additional clearance for the belt.
My original belt is just over .400” wide at the top. The belt is meant to be a serviceable part so I did some investigating on the Goodyear and Dayco websites and found a belt that is .44” wide and 28” effective length, Dayco part number 15280. I bought mine at my local Autozone with the Duralast brand name. It’s a cogged belt and I think that compared to a traditional v-belt will only help it conform to the smaller diameter pulleys.
The new belt was not going in as easy as the original belt came out. I turned it “inside out” so the small width at the bottom of the V was wedged between the motor housing and spindle pulley. The new belt went in with some effort but nothing difficult. You can see the tapered profile in the photo below.
Once the belt was inside the housing it was simple to twist the belt back to correct orientation. Hope this v-belt information is helpful.
Original Belt
Dayco 15280 Installed
Dayco Inside-Out
Dayco 15280 Profile
Dayco 15280 Part Numbers
The motor v-belt may be the original, see photo below. The belt was relatively easy to remove from the motor housing.
After reading about the v-belt on this site and others I purchased a 4L280 belt. There is no way this belt was going to fit my machine without complete disassembly. I tried removing the motor and loosening the cast aluminum motor housing but that did not provide enough additional clearance for the belt.
My original belt is just over .400” wide at the top. The belt is meant to be a serviceable part so I did some investigating on the Goodyear and Dayco websites and found a belt that is .44” wide and 28” effective length, Dayco part number 15280. I bought mine at my local Autozone with the Duralast brand name. It’s a cogged belt and I think that compared to a traditional v-belt will only help it conform to the smaller diameter pulleys.
The new belt was not going in as easy as the original belt came out. I turned it “inside out” so the small width at the bottom of the V was wedged between the motor housing and spindle pulley. The new belt went in with some effort but nothing difficult. You can see the tapered profile in the photo below.
Once the belt was inside the housing it was simple to twist the belt back to correct orientation. Hope this v-belt information is helpful.
Original Belt
Dayco 15280 Installed
Dayco Inside-Out
Dayco 15280 Profile
Dayco 15280 Part Numbers
