Servo Choices

[MartyS]

I have a servo on my cobra 4, and I am considering the purchase of another to use on smaller sewing machines. I recently purchased a singer 31-15, and it is difficult to sew slowly with the standard 1/2 HP clutch motor.

I have read most of the posts here that contain "servo" and from that reading I have gathered the following info:

Servos make it easier to sew slow without reducing torque.

Most servos on the market have the same bolt pattern as a typical clutch motor.

400 watts for smaller machines up to 750? for saddle stitchers.

2 types of speed controls, dial settings or push button with read out.

What I want to know is what people DO NOT like about the usability of particular servo motors, and

any known reliability issues.

For example on the servo I have the motor must be running in order to change the speed, which means you have to pull the top thread out of the needle and get down on hands and knees to adjust the speed while the motor is running. (in this case if the quality was the same I would opt for the dial)

I realize that sewing speed is a function of motor spindle speed multiplied by the various pulley diameters. It would be nice to see a chart that has various configurations listed that would enable normal folks to know the resulting lowest stitch speed, or at least a ball park idea, so when calling a dealer one would know enough to make reasonable decisions.

Pedal sensitivity: On the servo that I have, the speed control governs (limits) the top speed and does not change the pedal sensitivity. Do all servos act that way or do some models change the pedal sensitivity as you change the settings?

Lastly, my 31-15 has a leather belt, which by nature is stretchy and slips. So how much belt tension should one use on a servo. I recently re -sewed all the springs back on my kids trampoline with the cobra 4. Thats 90 linear feet for each pass. With a job that bid one tends to become more and more lead footed as you progress. From that experience I can say that at standard stock belt tension that flooring the pedal causes some belt slip and I think that allowing a bit of slip probably protects the machine from the excessive torque generated by the servo.

Servo suggestions and opinions appreciated. Thanks Marty

Edited September 25, 2011 by MartyS

[KAYAK45]

Hi Marty. What don't I like about my servo motor on my 31-15? Nutton Honey!

It is real sweet and gave me almost unlimited control. I reach the speed control knob, mounted on the left side of the motor, from my normal seated position. Unlimited speed range without changing thread or any of that kind of stuff. The variable range of the foot pedal for each speed setting on the motor has a large range from slow to fast. If you turn it to high you still have a lot of foot petal variance, just the low range gets real sensative. That's when I turn it down a notch. Low end and I watch the knot tie.

I bought my Servo from Bob @ toledo industrial and could not be happier with the unit and the service. It has built in gear reducers.

It really does mount in the same holes as my clutch did, but the belt length will change due to pulley size and position.

I have found no problem with the torque question and even have a V-belt with nearly no slip.

Go for it.

Kevin

PS want to buy a good clutch motor? I'll never need it!

[Wizcrafts]

I have a friend in Flint who bought a 441 clone that came with a servo motor with a digital readout and up/down push buttons. It too cannot be adjusted unless it is running, which is very dangerous. Furthermore, it shudders and drops out below 1 stitch per second, making it difficult to control around strap tips and sharp corners.

My home walking foot machine came with a 1/2 HP clutch motor. I replaced it with a SewPro 500GR, from Toledo Industrial Sewing machines. I had to move down an additional inch in belt length, due to the motor shaft being closer to the body that the clutch motor. I also dropped an inch because this motor has a 2" pulley and the original had a 3" pulley.

The SewPro motor has a dial on the back, to set the top speed. Lowing it from increases the pedal range for slow speeds. The unit has built in 3:1 gear reduction, so it doesn't lose power at 1 stitch every two or three seconds. It has more than enough power to slooooooowly penetrate 3/8 inch of belt leather, or 7/16"+ of bridle leather.

The SewPro 500GR only draws 300 watts at full speed (1500 RPM) and less at lower speeds. Otherwise, in idle, it draws no current that is measurable on a home power meter.

I now distrust most servo motors with a digital readout and push buttons for speed adjustment. Unless one can change the speed when it is not in motion and doesn't shudder and drop out at about 1 stitch per second, I'm not interested in having it on my machines. Bending over, to see under the table, with one foot on the speed pedal, to push buttons on the motor to control a big "Class 4" is not a fun thing to do. Plus, the thread has to be removed from the needle before adjusting it. Eventually, I had my friend push the buttons as I sewed a run of straps, making speed changes a two man job. This was necessary because the motor dropped out as I slowed down, with the top speed set at about 600 rpm. In contrast, the SewPro motor can go from well under 1 stitch per second, to 12 per second (on my walking foot machine with a 4" pulley on back), without touching the dial at all.

The SewPro would probably need a reducer wheel to run a big 441 machine, or maybe not. It is a powerful motor. If the big machine had a 6 or 8 inch flywheel pulley, I think the SewPro would do fine on its own.

[Techsew Ron]

I now distrust most servo motors with a digital readout and push buttons for speed adjustment. Unless one can change the speed when it is not in motion and doesn't shudder and drop out at about 1 stitch per second, I'm not interested in having it on my machines. Bending over, to see under the table, with one foot on the speed pedal, to push buttons on the motor to control a big "Class 4" is not a fun thing to do. Plus, the thread has to be removed from the needle before adjusting it. Eventually, I had my friend push the buttons as I sewed a run of straps, making speed changes a two man job. This was necessary because the motor dropped out as I slowed down, with the top speed set at about 600 rpm. In contrast, the SewPro motor can go from well under 1 stitch per second, to 12 per second (on my walking foot machine with a 4" pulley on back), without touching the dial at all.

The SewPro would probably need a reducer wheel to run a big 441 machine, or maybe not. It is a powerful motor. If the big machine had a 6 or 8 inch flywheel pulley, I think the SewPro would do fine on its own.

Not all servo motors with digital readout are the same.

The Techsew SmartServo motor, which we supply on most of our leather stitchers, does NOT have to be in motion in order to change the speed.

Our motor was engineered to change speeds at any time as long as the motor is on. I definitely do not recommend reaching down to adjust your motor while you're sewing! Sounds dangerous!

Ron

[awharnessshop]

I have a friend in Flint who bought a 441 clone that came with a servo motor with a digital readout and up/down push buttons. It too cannot be adjusted unless it is running, which is very dangerous. Furthermore, it shudders and drops out below 1 stitch per second, making it difficult to control around strap tips and sharp corners.

My home walking foot machine came with a 1/2 HP clutch motor. I replaced it with a SewPro 500GR, from Toledo Industrial Sewing machines. I had to move down an additional inch in belt length, due to the motor shaft being closer to the body that the clutch motor. I also dropped an inch because this motor has a 2" pulley and the original had a 3" pulley.

The SewPro motor has a dial on the back, to set the top speed. Lowing it from increases the pedal range for slow speeds. The unit has built in 3:1 gear reduction, so it doesn't lose power at 1 stitch every two or three seconds. It has more than enough power to slooooooowly penetrate 3/8 inch of belt leather, or 7/16"+ of bridle leather.

The SewPro 500GR only draws 300 watts at full speed (1500 RPM) and less at lower speeds. Otherwise, in idle, it draws no current that is measurable on a home power meter.

I now distrust most servo motors with a digital readout and push buttons for speed adjustment. Unless one can change the speed when it is not in motion and doesn't shudder and drop out at about 1 stitch per second, I'm not interested in having it on my machines. Bending over, to see under the table, with one foot on the speed pedal, to push buttons on the motor to control a big "Class 4" is not a fun thing to do. Plus, the thread has to be removed from the needle before adjusting it. Eventually, I had my friend push the buttons as I sewed a run of straps, making speed changes a two man job. This was necessary because the motor dropped out as I slowed down, with the top speed set at about 600 rpm. In contrast, the SewPro motor can go from well under 1 stitch per second, to 12 per second (on my walking foot machine with a 4" pulley on back), without touching the dial at all.

The SewPro would probably need a reducer wheel to run a big 441 machine, or maybe not. It is a powerful motor. If the big machine had a 6 or 8 inch flywheel pulley, I think the SewPro would do fine on its own.

Hey Bob I have 2 of the 500GR SewPro Motors, they will crank over a 441 no problem! I have one on an ase #9 too... which is a waste considering I cant open her up to go full speed! as it is it sounds like a train coming down the tracks! That motor is a beast and a half!

-Andrew

[Wizcrafts]

Not all servo motors with digital readout are the same.

The Techsew SmartServo motor, which we supply on most of our leather stitchers, does NOT have to be in motion in order to change the speed.

Our motor was engineered to change speeds at any time as long as the motor is on. I definitely do not recommend reaching down to adjust your motor while you're sewing! Sounds dangerous!

Ron

I wish my buddy had your motor then. I have to go in to his place tomorrow and sew 45 belts.

[KAYAK45]

I wish my buddy had your motor then. I have to go in to his place tomorrow and sew 45 belts.

Darnit Wiz, I forgot all about getting that Campbell High lift delivered to you. Maybe tomorrow, OK?

LOL

Kevin

[Wizcrafts]

Darnit Wiz, I forgot all about getting that Campbell High lift delivered to you. Maybe tomorrow, OK?

LOL

Kevin

Kevin;

You know that if you actually had a Campbell High Lift, you wouldn't part with it. I'll just have to slug it out and make do with my itsy bitsy Union Lockstitch machine, from 1910. It can't touch the Campbell machines and it only sews an honest 3/4 inch. I feel deprived ;-)

[Trox]

Hi,

my best servomotor is an Efka dc 1600 needle position motor. I adjusted it ones, no need for more adjustments or speed reducers. Full control on the foot pedal, stitch-by-stitch and full speed, very strong. It is only one problem, the price.

I bought a 600 W (220 V) brushless servo from Cobra Steve, with digital push buttons. Strong motor with speed limit settings, lowest speed setting 100 rpm. It does not have to be in motion in order to change the speed. The motor works very well, but is a bit sensitive on slowest speed limit; I will try to mount a speed reducer on it. Then it will be very good. If I should buy an other low price servomotor, I would buy the EPS servo from Cobra Steve. (Needle position motor) 350 $.

Trox

[JoeS]

Hi,

I have an old Singer 111-154 I'd like to use more and am also interested in reviews of servo motors from users. Would anyone recommend a Reliable or an Artisan or are the motors mentioned the top brands these days? It seems there are a lot more choices since the last time I was looking a few years ago and I'd like to make sure I get one that can push this thing thru what it and I can handle. I have a Boss and a 31-15 roller foot treadle and was hoping to use this one as a "tweener" for thread size and thickness.

thanks,

joe