gavingear Report post Posted November 14, 2008 If you look at the ACF-500 A at: http://www.artisansew.com/other.html It's a servo motor with needle positioner. It seems that this would be very handy for stopping in the down position (as when you want to pivot the work to change sewing direction), and to stop with the needle up so that the work can be removed, and thread snipped. Anyone using one of these? How well does it work? What kind of speed ranges do you get, and does the motor have sufficient torque at lower speeds? Thanks, Gavin Quote Share this post Link to post Share on other sites
Bree Report post Posted November 15, 2008 If you look at the ACF-500 A at:http://www.artisansew.com/other.html It's a servo motor with needle positioner. It seems that this would be very handy for stopping in the down position (as when you want to pivot the work to change sewing direction), and to stop with the needle up so that the work can be removed, and thread snipped. Anyone using one of these? How well does it work? What kind of speed ranges do you get, and does the motor have sufficient torque at lower speeds? Thanks, Gavin No I am using a non-positioning servo on my two machines with servos. I never felt the need for one because I am an expert flywheel jocky. I am always wanting to reach for the flywheel to do fine positioning. Jerry at Artisan had to convince me that it was easy to control their servo to sink the needle to the down position. I watched him do it on a T-3000 and he was right. It was easy. I have verified that on my own machine. You kick up the servo's low end torque by adding a speed reducer. That allows you to give it more oomph than you could without the reducer... or just grab that flywheel and give it a torque boost!! Quote Share this post Link to post Share on other sites
hidepounder Report post Posted November 15, 2008 No I am using a non-positioning servo on my two machines with servos. I never felt the need for one because I am an expert flywheel jocky. I am always wanting to reach for the flywheel to do fine positioning. Jerry at Artisan had to convince me that it was easy to control their servo to sink the needle to the down position. I watched him do it on a T-3000 and he was right. It was easy. I have verified that on my own machine.You kick up the servo's low end torque by adding a speed reducer. That allows you to give it more oomph than you could without the reducer... or just grab that flywheel and give it a torque boost!! I'm with you Bree...I can't keep my hand off of the flywheel either. I think that's because I learned on an Adler 205 that went from 0-60 in about a 1/2" of pedal! Quote Share this post Link to post Share on other sites
Bree Report post Posted November 15, 2008 I'm with you Bree...I can't keep my hand off of the flywheel either. I think that's because I learned on an Adler 205 that went from 0-60 in about a 1/2" of pedal! LOL!! I hear ya! My Juki would take off like bat out of hell with the clutch motor. I would get blisters from flywheeling it. And then I have all these treadle machines and you have to flywheel those all the time too. My mom flywheeled her old Singer which she taught me to sew on. I have done it on every sewing machine that I have owned so I guess it's burned into me. Quote Share this post Link to post Share on other sites
Hockeymender Report post Posted November 14, 2016 Goldstar GBSM-550S. I have four of these and have had them in service going on two years. They are easy to set up and work flawlessly. Plenty of power as well. http://store.allamericansewing.net/goldstar-gbsm-550-brushless-servo-motor-550-watt-34hp-with-needle-positioner Quote Share this post Link to post Share on other sites
Sonydaze Report post Posted November 14, 2016 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. Quote Share this post Link to post Share on other sites
dikman Report post Posted November 15, 2016 My first servo came with a needle positioner, mainly 'cos it seemed like a good idea at the time! I set it up, tried it and didn't really like it. In fact, I found with a servo set up to sew slowly I don't need the positioner. Also, be aware that a needle positioner won't work if a speed reducer is fitted. Quote Share this post Link to post Share on other sites
Hockeymender Report post Posted November 15, 2016 1 hour ago, dikman said: My first servo came with a needle positioner, mainly 'cos it seemed like a good idea at the time! I set it up, tried it and didn't really like it. In fact, I found with a servo set up to sew slowly I don't need the positioner. Also, be aware that a needle positioner won't work if a speed reducer is fitted. I have speed reducers on two of mine and they work just fine with the needle positioners. Quote Share this post Link to post Share on other sites
Gregspitz Report post Posted November 15, 2016 I have one on my Techsew 5580RF and it is wonderful..full control fast and slow and great torque and the needle positioner works great with the servo. I wouldn't do it any other way from now on. Quote Share this post Link to post Share on other sites
dikman Report post Posted November 16, 2016 I stand corrected then, Hockeymender. Mine goes into meltdown if I use a speed reducer . I have read of others having the same problem, but if yours works then it must depend on the servo brand? Quote Share this post Link to post Share on other sites
Gregspitz Report post Posted November 16, 2016 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 Quote Share this post Link to post Share on other sites
Oliver76 Report post Posted October 4, 2017 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 ? Quote Share this post Link to post Share on other sites
CowboyBob Report post Posted October 5, 2017 Try a larger motor pulley. Quote Share this post Link to post Share on other sites
geiercustomleather Report post Posted November 28, 2019 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? Quote Share this post Link to post Share on other sites
geiercustomleather Report post Posted November 28, 2019 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 Quote Share this post Link to post Share on other sites
dikman Report post Posted November 28, 2019 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. Quote Share this post Link to post Share on other sites
Pterytus Report post Posted December 5, 2019 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. Quote Share this post Link to post Share on other sites
Tulsaman Report post Posted June 6, 2021 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. Quote Share this post Link to post Share on other sites
Sonydaze Report post Posted June 7, 2021 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. Quote Share this post Link to post Share on other sites
bj139 Report post Posted June 17, 2021 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. Quote Share this post Link to post Share on other sites
Striker Report post Posted January 19, 2022 Can someone help me with the circuit diagram of the needle positioner? I have JIN PSM550E which is a rebranded Redsun R9. I purchased an ISM synchronizer as the compaitable synchronizer is not available. if someone can send few pictures of open synchronizer or draw a circuit diagram, it would be really helpful Quote Share this post Link to post Share on other sites