servo motor startup speed

[GerryR]

When you say "smaller," from what diameter to what diameter.  In general, if the pulley it is driving remains the same, it would lower the speed and increase the torque, so there shouldn't be any problems.

[fibersport]

From what I can find, the original pulley on the Reliable/Sailrite motor is 60mm, I am currently running a 45 or 50mm pulley.  Sailrite specifies that you should not run their motor with their "Monster pulley", not sure if it's because of weight or diameter.  I do know that the Sailrite motor comes with a small diameter toothed pulley so I would think going with a smaller grooved pulley would work as well.  

[GerryR]

From what I could find on their website, it states that the "Workhorse Servo Motor (110V) should not be used with heavyweight balance wheels," so pretty sure it's an inertia problem.  Going down to the 45-50mm pulley gives you a slower speed and higher torque advantage over the 60mm, which I believe is in the direction where you were headed (?).

[fibersport]

Exactly.  I built a speed reducer and would loose some benefit using a 60mm pulley.  However, I would try the motor without a speed reducer first to see how I like it.  If it's not right, I can add my speed reducer and or look for a smaller pulley.  

[fibersport]

Got some interesting information tonight from Reliable.  I was told that the Quietsew 6000SM has a minimum speed of 500 rpm.  Different pulleys are able to be installed as well but the needle positioner will not work with different size pulleys.  I guess the benefit of the 6000sm might be the controllable startup speed.  It would be interesting to find out the minimum speed of the Consew 550 (and clones).

Edited September 28, 2023 by fibersport

[Wizcrafts]

1 hour ago, fibersport said:

It would be interesting to find out the minimum speed of the Consew 550

Are you referring to the Consew Premier CSM550-1 servo motor? If so, the start up speed is barely spinning. I have its predecessor, the Family Sew FS-550s on several of my sewing machines. Some power the machines directly, with a 50mm pulley, while others feed 2:1 or 3:1 speed reducers. If there is little to no load on the motor, it starts spinning very slowly. Under load I have to give it more pedal or knob rotation to overcome the resistance. The machine will still run very slowly unless I turn the limiter knob up high. Even then, the slow speed is fairly easy to control with my steady foot.

One of my machines fed directly from a FS-550s is a long bed walking foot machine with a 5" hand wheel pulley. I can run the machine at 1 stitch per second with ease and it ramps up from zero smoothly. I frequently use that machine to sew patches onto the back of bikers' vests. The analog servo gives me total control over the speed. I can stop it with the needle down to turn corners.

[fibersport]

Yes, that's the one.  I'm still on the fence over the digital and analog motors, or do I just sit tight and live with what I have - decisions decisions ..... I really think all would be fine, I just need to dive in and spend more time sewing, if only my job didn't require that I be there every day!  Thanks again for your input Wiz -

[CowboyBob]

12 hours ago, fibersport said:

Got some interesting information tonight from Reliable.  I was told that the Quietsew 6000SM has a minimum speed of 500 rpm.  Different pulleys are able to be installed as well but the needle positioner will not work with different size pulleys.  I guess the benefit of the 6000sm might be the controllable startup speed.  It would be interesting to find out the minimum speed of the Consew 550 (and clones).

I got my tachometer out & the lowest speed running a machine is 150rpm with a CSM-550-1 and that's why we use them on everything.No boards to blow either.

[GerryR]

1 hour ago, CowboyBob said:

I got my tachometer out & the lowest speed running a machine is 150rpm with a CSM-550-1 and that's why we use them on everything.No boards to blow either.

Is that motor shaft speed or gear reducer output speed?

[Gump]

Hate to argue with Reliable, but my Sewquiet 6000 runs at 198 rpm minimum at a steady rate. I used a laser tach directly on the motor pulley.