servo enduro Servo motor still too fast

[Kcstott]

3 hours ago, AmyK said:

Show off, I’ll drink your beer! Lol

More like watch this knuckle head Put a lock stitch through his finger. 
the nice thing about servo motors is the torque power they have to stitch through nearly anything, the bad thing is the anything could be your finger and the machine won’t care. 
hope you get this figured out. I think you need to find someone that will sell you and install a speed reducer for you. The guy you mentioned doesn’t seem to be very helpful. 
wish I or you were closer I’d come over and take care of it for you for nothing. 

[shoepatcher]

AmyK,

The main shaft on top of a Juki is  .495-.498". Hope that helps.

glenn

[chrisash]

On 10/16/2020 at 5:37 AM, Uwe said:

@AmyK Don’t give up on the machine head, it’s the motor control that’s causing you grief. That poorly implemented speed ramping control on the Enduro motors is a real problem. Speed control is done via a light sensor and speed varies depending on how much light hits the sensor. The factory combo of sensor and light blocker is WAY too sensitive, jumping between full light to zero light with the tiniest of pedal movements. I also ended up making a special triangular light blocking “flag” to get any sort of real world ramping of speed. The motor is indeed capable of graduated speed control, just not with the factory bits. Whether you want to bother modifying the speed control on your motor is up to you.

@toxo thanks for the demo and details on your hand wheel pulley. That speed control looks just about perfect to me, sweet! I’m very much in favor of this pulley-as-a-hand-wheel solution. I really don’t care for the in-between pulley speed reducers.  

@Gymnast the 100 RPM starting speed is the lowest I’ve seen on the motors I’ve researched.

 

Just for reference, this is the kind of speed control I’m getting with my servo motor and a standard hand wheel:

 

Please can you tell me what servo you brought and any mods to it

[DonInReno]

My vote also goes to a speed reducer with the servo.  No amount of messing with the servo’s controls or bits will produce the low speed AND torque AND control ability.

A 3:1 reducer also increases the low speed torque by 3x, which literally will change how you sew.  A little 500w motor will have the startup torque of a 1500w motor.

 

 

[Gymnast]

On 10/16/2020 at 6:37 AM, Uwe said:

@Gymnast the 100 RPM starting speed is the lowest I’ve seen on the motors I’ve researched.

I just read a few specifications for a Dürkopp Adler 525i-811. As far as I can see, it is a fast stitching zig zag industrial machine. A user wanted it second hand to be used for DIY sailmaking and some marine canvas work. It is not a walking foot machine.
https://www.duerkopp-adler.com/en/main/products/shoes_FB_ZZ/525i-811.html

The gearing will normally be 1:1 to the motor, but it is possible to change it. When I read the parameter settings for the controller here, you can set the minimum speed of the motor down to 10 RPM. It is page 15 here:
https://www.duerkopp-adler.com/commons/download/public/525i/0791_523901.pdf 

So it is much lower speed for this kind of motor compared to what I have seen before.