speed reducer

[Northmount]

The noise/squeal of that motor would make me even crazier than I am already!

Tom

Chances are a diode or SCR is shorted out.  If so will cook the windings or some part of the circuit before long.  The squeal is similar to the sound of a shorted diode in an alternator.  Then the windings start to stink as it gets worse.

[TinkerTailor]

1 hour ago, northmount said:

The noise/squeal of that motor would make me even crazier than I am already!

Tom

Chances are a diode or SCR is shorted out.  If so will cook the windings or some part of the circuit before long.  The squeal is similar to the sound of a shorted diode in an alternator.  Then the windings start to stink as it gets worse.

I figured the cheap motor control circuit is struggling with the 50hz power in the uk, being designed for 60hz.

[Matt S]

On 01/11/2016 at 7:20 PM, Sticks said:

http://www.ebay.co.uk/itm/111721081685?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

 

Does anyone have any experience with this motor.?

I always find it odd when people advise to use the servo INSTEAD of the reducer when most seem to use both together.

That suggests the servo (affordable ones) motors are missing something.?

Or is it me who is missing something.lol

I have that servo on my Adler 67. Works fine but there's not much gradiant to the pedal speed control. I have tweaked everything I can find and I only get two levels of speed within each speed setting.

[dikman]

I will have to disagree with you on this one, Sticks. My first machine had a clutch (of course) which scared the daylights out of me the first time I used it!! I made a larger handwheel pulley and made a speed reducer (modified a couple of times) in an attempt to control this beast, all to no avail. Yes, they slowed it down some, but I still had issues, and without fitting a gearbox(!) had reached the limit of a mechanical solution.  After reading about servos here (and finally figuring out what they were talking about) I bought one from Aliexpress, Chinese company, of course but with a warehouse here in Australia. Cost was $250 Aus, about $220 US. Best thing I bought, in fact I bought two more! No problems so far, and the control it gives me is awesome.

There is no way I would spend $1000 on a servo, not for my needs (and I'm pretty sure many will agree, it's a bit over-the-top for a hobbyist).

[Matt S]

12 hours ago, Sticks said:

I could be way off base with this observation,but from what I have read, there doesnt seem to be much point (unless you are buying a very expensive motor) in replacing a clutch with a servo motor.

I am guessing the caveat within the general mantra of 'replace your clutch with servo for much more control instantly' is that it must not cost less than 1000 dollars. 

Im sure someone can correct me on this.

Well the Adler 67-63 has a very small balance wheel and even with the smallest available pulley wheel, the old clutch motor (with very little clutch left) it would jump from a standstill to about 900SPM. I didn't want to fit a speed reducer because the end of my table is quite cramped. The cheap servo was a £90 drop-in part that allowed me to dial from 200RPM  (150-odd SPM) up to several thousand, which is useful for bobbin winding. I would like more of a gradient so I could throttle up and down on the fly (slower on the corners, faster down the long straights) without having to stop and adjust the speed but for the price I can't really complain.

[gigi]

Currently I have this setup: the original old 0,24 kW clutch motor at 1400 RPM, a small motor pulley (40 mm from https://www.college-sewing.co.uk). Motor is controlled by a 0,75 kW Yaskawa V1000 frequency inverter drive bought in used condition from eBay (about 50 bucks). Speed is preset with a potentiometer knob, clutch is engaged and disengaged by original machine pedal. Advantage: you have good torque from 0 to 1400 RPM.  Also not a lot of changes to original setup. Works even for veg-tan leather, at least 6-7 mm. I have 2 machines with the same type of setup: a Pfaff 335 and a Durkopp 239-525.   I am working to develop a potentiometer pedal and replace the clutch motor with regular motor to vary the speed easier, without having to stop (even though I can manage to turn the potentiometer knob while sewing).  Just a different setup...

Edited November 7, 2016 by gigi

[TinkerTailor]

3 hours ago, gigi said:

Currently I have this setup: the original old 0,24 kW clutch motor at 1400 RPM, a small motor pulley (40 mm from https://www.college-sewing.co.uk). Motor is controlled by a 0,75 kW Yaskawa V1000 frequency inverter drive bought in used condition from eBay (about 50 bucks). Speed is preset with a potentiometer knob, clutch is engaged and disengaged by original machine pedal. Advantage: you have good torque from 0 to 1400 RPM.  Also not a lot of changes to original setup. Works even for veg-tan leather, at least 6-7 mm. I have 2 machines with the same type of setup: a Pfaff 335 and a Durkopp 239-525.   I am working to develop a potentiometer pedal and replace the clutch motor with regular motor to vary the speed easier, without having to stop (even though I can manage to turn the potentiometer knob while sewing).  Just a different setup...

Bass drum pedals from drum kits may be a good source for a pedal to mount a potentiometer too.

[TinkerTailor]

VFD's generally cost the same if not more than a servo new. If you find one used, go for it. If you are ordering new, go with the servo. It is less work and cheaper. And yes, the motor needs to be wired into the vfd and the vfd plugged into the wall. Some rewiring is likely to be necessary.

[gigi]

1 hour ago, TinkerTailor said:

Bass drum pedals from drum kits may be a good source for a pedal to mount a potentiometer too.

Thank you for the idea! We need to find a potentiometer with low amplitude movement to work with the pedal or a magnetic sensor.

1 hour ago, Sticks said:

Any photos.?

My husband did the rewiring. First he read the manual to see how the connections should be made (they may differ from other inverters). 

Edited November 7, 2016 by gigi

[TinkerTailor]

Machinists use vfds all the time to use  3 phase 220 volt machine  motors with single phase 220 power at home. It is important to get the right type with the right input and output.  Look on sites like practical machinist for info and used vfds for sale.