The lower wheel has a drive pulley with a V-grove to accommodate the notched V belt. To cut the grove in the drive pulley I need to some how spin the thing so I made a smaller pulley and cut a V grove in that on the router table with a V grove bit, then attached the temp pulley to the drive pulley so I could spin it up off the motor – crikey. I don’t have any wood turning tools so I hade to make my own to cut the V-groove by grinding down a old file to the correct V profile and then put a cutting edge on it. Once all this prep work was done actually cutting the V-grove was quite straight forward.