Anyone using a servo motor with needle positioner?

[Gregspitz]

my servo was modified to use with a speed reducer from Techsew...it works great. It was quite a day putting it all together though but well worth it

[Oliver76]

Sorry for digging up the old thread , but i recently bought a servo motor as well . i´m also using a 3:1 speed reducer  , but i can´t seem to get the needle positioner working.
The motor lifts the needle once or twice , but then goes into error mode . In which way did you guys tune or modify the synchronizer to get it working , if i may ask ? 

[CowboyBob]

Try a larger motor pulley.

[geiercustomleather]

On 10/4/2017 at 3:31 PM, Oliver76 said:

Sorry for digging up the old thread , but i recently bought a servo motor as well . i´m also using a 3:1 speed reducer  , but i can´t seem to get the needle positioner working.
The motor lifts the needle once or twice , but then goes into error mode . In which way did you guys tune or modify the synchronizer to get it working , if i may ask ? 

So did a larger motor pulley allow it to work? 

[geiercustomleather]

On 10/5/2017 at 11:05 AM, CowboyBob said:

Try a larger motor pulley.

Bob,

What size motor pulley for a 3-1 SR and needle positioner are you recommending? I am using a 45mm and it works great expect for the needle positioner which errors out after one or two turns. Motor came with a 75mm which I replaced when I added the SR2.

Thanks,

Billy

[dikman]

I had the same problem but fitting a larger pulley didn't work. It appears some servos work with a speed reducer/positioner combo and some (probably most, I suspect, don't). A member on here posted about modifying the positioner to get it to work, he did it successfully but again it didn't work for me. Open up the positioner and inside is a disc with a magnet attached at the rim. There was a hole on the opposite side for another magnet which he attached, this turned it into a dual sensor unit. It is then necessary to access the settings in the servo and change it to a dual sensor (or whatever they call it) pickup. It worked for him but in my case while it eliminated the error message I did not have the option in the servo to change the setting to a dual sensor. I could not set it to stop either needle up or needle down, it was inconsistent so of no real value.

[Pterytus]

The double magnet mod on my Aerostar Servo Sensor still works fine... ;-)

But for my big Adler I ordered another brand of Servo with a differnt Sensor type. It's a 750W Jack Servo and the (big) Sensor it came with is not magnetic as on the Aerostar but optical with two slotted discs inside for upper and lower needle pos. You can adjust (rotate) the discs to match the exact needle-positions you want. My setup also includes a speedreducer but there does not seem to be any restriction in terms of transmission rato, at least with my 0.215 overall transmission ratio (motor to machine) everything works fine without mods.

The Jack seems to generate less vibration but starts at 200rpm as opposed to the Aerostar which starts at 100rpm. Both 750W and they cost about the same by the way.

[Tulsaman]

On 11/14/2016 at 3:17 PM, Sonydaze said:

I go with needle positioners.  They make corners faster and easier. I set mine so they stop down and go up when you rock back on the foot pedal.  I recently got a newer 750 watt servo, it has proven to have much better torque and slow speed control.  After several years with servo motors, I don't know how I used to sew with a clutch motor... although I do remember a sore hand from stopping and turning the wheel.

It's hard to find if or what brand of servo's with needle positioners will have the heel back function. Or what you call the rock back. Especially with the 750 watt brushless.  Can you recommend one that can get me going? I have a Brother B837 it will go on.  I run a Juki 1510N-7 for my main functions but the Brother is for backup and certain nasty dirty type repairs.

[Sonydaze]

6 hours ago, Tulsaman said:

It's hard to find if or what brand of servo's with needle positioners will have the heel back function. Or what you call the rock back. Especially with the 750 watt brushless.  Can you recommend one that can get me going? I have a Brother B837 it will go on.  I run a Juki 1510N-7 for my main functions but the Brother is for backup and certain nasty dirty type repairs.

Hmmm I thought all servo motors with a needle positioner can be set to stop with the needle either up or down, then reverse when you push your heel down. I have 3 different brands (the chinese ones that come with 3 little pages of instructions that are poorly translated to english) and they all do this. I see you are in New Hampshire, but if it helps, I buy my motors from Marc at Mason Sewing in Vancouver, BC.

[bj139]

I found with the needle positioner set to stop down, if the needle was coming up, it proceeded to make a new hole to get to needle down.  Most times I did not want  a new hole.  I removed it.  Stopping needle up may be good but I didn't try it much.