Pintodeluxe Report post Posted October 11, 2017 Does anyone know a source for a small motor pulley that will fit a Rex 550w Servo? I recently installed Rex servos on a Consew 226 and a Consew 206RB-1, and the new motors came with 3" pulleys. As expected, they ran a little faster than I wanted so I went shopping for some smaller motor pulleys. Techsew sent me a 45mm O.D. pulley that they said would fit, but it had a 3/4" shaft. My Rex servos have a 5/8" shaft size. All of the 1-1/2" to 1-3/4" pulleys I can find have 3/4" bores. I did find 1-3/4" x 5/8" standard Chicago Pulleys at the hardware store, but they needed to have the set screw "knuckles" ground off before they would fit against the motor. These actually work pretty well, but it would be nice to have a source for a direct bolt-on part. Also, the Chicago pulley is a tad too wide for a 3/8" V belt. Another idea that came to mind is adding a bushing to make a 3/4" bore pulley fit the 5/8" shaft. Then you would have to cut a slot in the bushing to allow the woodruff key be inserted (or perhaps use a set screw instead). Any easy answers out there? I would love to find a 38mm O.D. pulley that fit a 5/8" shaft. Thanks so much. Quote Share this post Link to post Share on other sites
brmax Report post Posted October 11, 2017 (edited) You might try one of the dealers that sell that style. Some are on the site here in headings. Other than that if a thread tap tool is available this may help fix your correct width pulley predicament,locally. Good luck Floyd Edited October 11, 2017 by brmax Quote Share this post Link to post Share on other sites
andymanak Report post Posted October 11, 2017 A 5/8" to 3/4" split sleeve will be the easiest and cheapest, something like this should work: http://www.globalindustrial.com/p/motors/pulleys-sheaves/bushings/reducer-bushing-srb101220-galvanized-steel-58id-x-34od-114l?infoParam.campaignId=T9F&{lpurl}&vt-pti=B984124&gclid=CjwKCAjwgvfOBRB7EiwAeP7ehnb0-cdZ96n2w5V9kOuP0vGrbdcj-r3SScS39p_CG9oVjP_CYp52kBoCYlMQAvD_BwE Quote Share this post Link to post Share on other sites
DrmCa Report post Posted October 11, 2017 The torque on the pulley is not too big, you may be able to get away with a split bushing and no woodruff key Quote Share this post Link to post Share on other sites
Gregg From Keystone Sewing Report post Posted October 11, 2017 5/8" bore pulley is very common for many new servo motors. Consew's clutch motor from I think the sixties and seventies made in Japan had this pulley bore. Quote Share this post Link to post Share on other sites
Pintodeluxe Report post Posted October 11, 2017 Many good ideas here. Thanks for the link to the split sleeve Andy, that would be a quick fix. Grainger lists a 1-1/2" pulley with a 5/8" bore, but the picture is just a stock image of a 4" pulley so I'm not sure if it would work. Thanks again for all the helpful replies. Quote Share this post Link to post Share on other sites
DrmCa Report post Posted October 11, 2017 I find that Grainger is the kind of business where you get somewhere only with a walk in. Quote Share this post Link to post Share on other sites
CowboyBob Report post Posted October 11, 2017 (edited) You might want to double check your measurement it might be close to 5/8 which is 0.6250 & 15 mm is 0.5906 which is the diameter on most new servos.If there's a nut to hold the pulley on then it should be the 15mm. Edited October 11, 2017 by CowboyBob Quote Share this post Link to post Share on other sites
Pintodeluxe Report post Posted October 11, 2017 Okay I'll check with the calipers to see what the actual dimension is. Thanks Bob. Quote Share this post Link to post Share on other sites
Gregg From Keystone Sewing Report post Posted October 11, 2017 *I got 14.89mm, .0586", or .37/64" or 19/32" if you will. *Not exactly the 5/8" I was thinking of, I need to check my numbers again! Quote Share this post Link to post Share on other sites
Uwe Report post Posted October 11, 2017 (edited) That Rex motor looks very much the Family Sew variety. Your main problem may be that these motors originate in the metric part of the universe and you're trying to match up an imperial pulley. My Family Sew motor has a 15mm shaft and I got some SM50 50mm pulleys at UniversalSewing.com a while ago that fit nicely. Edited October 11, 2017 by Uwe Quote Share this post Link to post Share on other sites
Pintodeluxe Report post Posted October 11, 2017 That's great info Uwe, thanks for the pictures and post. Quote Share this post Link to post Share on other sites
GPaudler Report post Posted October 11, 2017 The first place I always look for belts, pulleys, bushings and almost anything else is McMaster-Carr: https://www.mcmaster.com Quote Share this post Link to post Share on other sites
Gregg From Keystone Sewing Report post Posted October 12, 2017 14 hours ago, GPaudler said: The first place I always look for belts, pulleys, bushings and almost anything else is McMaster-Carr: https://www.mcmaster.com McMaster-Carr is awesome, I buy a lot of stuff from them. A lot of hard to find stuff shows up at my door a day after ordering, they must have a warehouse close by to me. Quote Share this post Link to post Share on other sites
SheltathaLore Report post Posted October 12, 2017 5 hours ago, Gregg From Keystone Sewing said: McMaster-Carr is awesome, I buy a lot of stuff from them. A lot of hard to find stuff shows up at my door a day after ordering, they must have a warehouse close by to me. McMaster is amazing. They sell EVERYTHING. incidentally, they sell wool felt cord in various sizes, which is apparently the perfect stuff for oil wicks - and a couple feet is practically a lifetime supply. Quote Share this post Link to post Share on other sites