N_Cook wrote in message
...
Useful to remember if no machine shop available for making a bulbous
pulley,
if faced with replacing a motor and its the wrong speed range so forced
change of pulley , or smaller spindle diameter. Except the ridge is
semi-circular profile here and bodge job would be chamfered edges but
starting from a brass rod it would be a lot easier to fashion leaving
central ridge, bodging 2 cone segments and 2 end faces , than fully
bulbous
without a lathe



Back working with a silicone rubber flat belt, shame it is bright orange.
Looking under x30 the original band had a furrow along its centre. I've
since found a salvaged variant on this pinion , 2 angled cones with an
included angle of about 110 degrees but no ridge , just a rounded join
probably about .5mm diameter again. The band cannot deflect that much so
must ride on that central edge, like the one I just fixed. Perhaps bulbous
ones are just kinder on the rubber