Development of best servo motor for leather sewing machine

[Cumberland Highpower]

 

On a standard size Adler 205 clone, the jog dial concept is a bit ridiculous to redundant.  The handwheel is as close a reach as the jog dial when you're sitting in front of it.  Adler has it on the 969 because the handwheel is a much further reach.   A jog wheel on a standard machine is also a poor idea because of it's diameter.  The handwheel is very large, and can afford a very fine control over the needle.  

 

The "long arm" machines you're mentioning (Such as the model below) with the extra front mechanical hand wheel are probably 1% of the heavy stitchers out there.  

I'd gamble most anyone with one of those is either set up with a heavy Clutch Motor, or a quality Efka or similar. I just pulled the first random long arm machine image I found with a Google search. As you can see this lower end Chinese machine looks like it's equipped with a either Ho Hsing servo or a close clone that's probably 5x the cost of a run of the mill Chinese brushless servo.  I kinda doubt a $100-150 servo you're working on would be the right piece of that particular puzzle? I would maybe suggest not concentrating on that particular market?

 

You're soliciting input from a forum of fairly competent people but It feels like you're debating the input?  Is it that you've already designed the "perfect" servo and just haven't released it yet, and don't like what you read?

Edited July 5 by Cumberland Highpower

[CowBoyOUTLAW]

14 hours ago, Tastech said:

Perhaps 2 versions of motor 120 volts for north America and 220-240 volts for the rest of the world .

Both 110-120V and 220-240V are available from Kinedyne servo motors

[CowBoyOUTLAW]

2 hours ago, Cumberland Highpower said:

 

On a standard size Adler 205 clone, the jog dial concept is a bit ridiculous to redundant.  The handwheel is as close a reach as the jog dial when you're sitting in front of it.  Adler has it on the 969 because the handwheel is a much further reach.   A jog wheel on a standard machine is also a poor idea because of it's diameter.  The handwheel is very large, and can afford a very fine control over the needle.  

 

The "long arm" machines you're mentioning (Such as the model below) with the extra front mechanical hand wheel are probably 1% of the heavy stitchers out there.  

I'd gamble most anyone with one of those is either set up with a heavy Clutch Motor, or a quality Efka or similar. I just pulled the first random long arm machine image I found with a Google search. As you can see this lower end Chinese machine looks like it's equipped with a either Ho Hsing servo or a close clone that's probably 5x the cost of a run of the mill Chinese brushless servo.  I kinda doubt a $100-150 servo you're working on would be the right piece of that particular puzzle? I would maybe suggest not concentrating on that particular market?

 

You're soliciting input from a forum of fairly competent people but It feels like you're debating the input?  Is it that you've already designed the "perfect" servo and just haven't released it yet, and don't like what you read?

I 100% understand your opinion, but many modern standard arm sewing machines use JOG dial, for example Durkopp Adler 967, you can see the jog on some other computerized upholstery sewing machine. 
Ho Hsing i90 is an excellent servo motor for heavy duty industrial sewing machines, the price in China is over $500.00 USD, and about $400 USD in Europe, it is too higher for 205-370 Clone or 441 Clones.

Clutch motor is very bad for leather sewing machine, we searched good servo motor for our CowBoy leather sewing machines for about 6 months, no affordable servo motor can work for us, that's why we start to produce servo motor. 

We has been selling servo motor in United States for about 2 years, all Tandy CowBoy 797 sewing machines come with Kinedyne HM-750SL servo motor. 

However we must keep innovation. Last October, our Italian dealer suggested the JOG Dial, we make it reality. Last month, our Sweden dealer suggested Half Stitch we made it reality....

[kgg]

3 hours ago, dikman said:

I think it's fair to say that most don't want fancy options that they will never use

I totally agree. 

I think as a cheap old geezer the hobbyist is looking for simple operation, reliable and most importantly cost effective. I can count on one hand the number of times I have changed the speed on my servo motors. Once I find the comfortable "spot" that is where it stays. To the average hobbyist cost is always king whether it is a complete machine setup or a servo motor.

9 minutes ago, CowBoyOUTLAW said:

However we must keep innovation.

Why?? Just build simple good working motors for the majority of your customer base that are cost effective. 

kgg

[CowBoyOUTLAW]

9 hours ago, Wizcrafts said:

One problem I have had with digital servo motors vs analog servo motors is the jerky start up. I can understand that lowering the startup speed to 50 rpm will be less jerky than a 100 or 200 rpm startup, it will still engage with a hit. Analog servo motors I have start at zero and smoothly increase in speed as the pedal is pressed. There is no jerk at startup on those motors. I have helped convert several Cowboy and Cobra 441 clones and one Union Lockstitch machine from digital to analog servos for this very reason. Once the change was made, the owners never complained about being able to control the machine or position the needle as needed.

I would be happy to have a digital servo motor that started at zero and increased in speed only as I pressed down more on the speed pedal. I don't like motors that start fairly slow, then speed up on their own ("ramp up"). The motor speed should be pegged to your foot position on the speed pedal. If one needs an external speed knob, the same should apply. As the knob is rotated, the speed should increase.

Because many servos lack high torque at lower speeds. I can see that the ones having more coils will have more low end torque. I would gladly pay more for an analog servo motor that eliminated to need for a speed reducer. However, when sewing thick veg-tan leather, the faster one sews, the greater the heat that is generated on the needle. I found that when I sewed at 15 stitches per second, smoke came from the needle! This also began melting the bonding agent on the nylon thread. The result was a weakened stitch line. I doubt that I am the only person who prefers to sew slowly to maintain control of the stitch line and needle placement, as well as to keep down the heat on the needle. I typically sew within a range of 1 (for detailed designs) to 6 or 7 (on straight edges) stitches per second. When I sew at higher speeds, I use an edge guide. When the leather is thinner, I can sew faster than when it is very thick. It can be dangerous to sew 3/4 inch at 5 or more stitches per second. If a fast moving needle is deflected by thick layers and breaks, it could embed itself in one's skin! Ask how I know this!

Yes, digital servo motors will lose torque at low speed, and the motor will vibrate or noise when start up, because the torque is not enough. When get change, please test Kinedyne HM-750SH sero motor from Ryan or Toledo Industrial Sewing Machine, I think you will be surprised with torque and speed control.
Really appreciate for your information. Can you test 10 stitches per minitue? See if smoke came from the needle!  Now we use 45mm pulley, the lowest sewing speed of CowBoy CB4500 is 10 SPM. If the needle still smoke, we will try to use smaller pulley or modify the program. And when thin leather, we have speed controller that allow you to increase speed in a second.
Thanks again for your informtion about the lowest speed!
 

[CowBoyOUTLAW]

15 hours ago, kgg said:

Need a basic servo motor that has:

1. Has to have excellent low speed startup.

2. Has to have a 12 coil servo motor or at less 9 coils if it is a brushless electronic servo motor.

3. Give the customer the option of a Brush or a Brushless servo motor.

i) If the customer chooses a Brushed servo motor if the speed dial was able to be mounted on the front of the table rather then on the motor's body they would be perfect particularly for new users. 

ii) If the customer chooses a Brushless servo motor it should be just a simple matter of being able to flip a toggle switch like @Cumberland Highpowerhas suggested rather then having to disconnect the needle positioner plug from the electronic control panel or having to go into the menus.

I prefer the brushed rather then brushless servo motor. No fancy menus or electronics, no needle positioner just set the max speed hit the " go" pedal and sew. I have two brushless servo motors, one on a LS-341 clone and one on a TSC-441 clone and two brushed servo motors, one on a Juki DNU-1541S and one on a Juki du-1181N. The needle positioner on both the Brushless servo motors have been Disconnected. 

The brushed servo motors are much simpler to use for new people and are a lot easier diagnosed when a problem arises.

4. All new features like "Jog" should be options that the customer can choose to purchase if needed. 

I follow the "KISS" rule.

To reduce startup jump, more controllable sewing speed. However even through you get increase torque it from adding a speed reducer it should be not used as the main reason for installing one as you don't want to over stress internal parts on some class of machines.

I disagree. Push the "go" pedal and sew.

kgg

 

 

All modern servo motors should be brushless, we developped speed controller and JOG, soft sart (slow start) for better controling speed, especially for beginner.

[dikman]

When I bought my first servo I was fascinated by all the settings in the menus, over time I realised that for the most part they were irrelevant as once I had it running to suit me I didn't need to change anything again. Like KGG once I have it set to an optimum speed (for my needs), including a speed reducer as the generic servos need one, then I don't need to change anything. Your Kinedyne is apparently a superior servo compared to the array of generic servos available but the price reflects that and while I would love one as a hobbyist spending that sort of money isn't justified when the cheaper option is working fine. Plus I have more than one machine!

I'm not sure which part of the market you're aiming for, the vast majority on here are hobbyists and like me can't justify the expenditure for a Kinedyne so you're unlikely to achieve much in the way of sales and if you're aiming for the commercial market you've come to the wrong place.

[CowBoyOUTLAW]

12 hours ago, fibersport said:

Talk about having your cake and being able to eat it!  A few thoughts - keep the price comparable to the Reliable or Sailrite (before their price jumped) models so under $200-$250, 12 coil, some sort of trade in program for those that bought analog units from you, made in the USA (that might be tough).  Great thoughts - hope it happens.

Our competitor is Ho Hsing i90 and Efka servo motor, not Reliable or Sailrite😁

[CowBoyOUTLAW]

13 minutes ago, dikman said:

When I bought my first servo I was fascinated by all the settings in the menus, over time I realised that for the most part they were irrelevant as once I had it running to suit me I didn't need to change anything again. Like KGG once I have it set to an optimum speed (for my needs), including a speed reducer as the generic servos need one, then I don't need to change anything. Your Kinedyne is apparently a superior servo compared to the array of generic servos available but the price reflects that and while I would love one as a hobbyist spending that sort of money isn't justified when the cheaper option is working fine. Plus I have more than one machine!

I'm not sure which part of the market you're aiming for, the vast majority on here are hobbyists and like me can't justify the expenditure for a Kinedyne so you're unlikely to achieve much in the way of sales and if you're aiming for the commercial market you've come to the wrong place.

Thanks for your opinion!
Before making Kinedyne servo motor, we sell other brand "servo motor" for our leather sewing machine! The fail rate of board is about 7%. We spent a lot of time and money for service after sale!
Cluth motor is too bad for leather sewing machines, so we produce Kinedyne 750L economical servo motor, it is durable motor with good price, but the minimum speed is 300 RPM, customers still need to buy speed reducer!
Why waste money to buy speed reducer? We developped Kinedyne HM-750SH low spee, high torque servo motor. 
Finally we spend less money with high performance servo motor!!

[dikman]

If you consider Ho Hsing and Efka as your competitors then you've come to the wrong place to promote your servo as very few on here buy those motors (other than as used units that come with a second-hand machine). You can't compete with what most of us buy, generic Made-in-China servos off ebay (or from a dealer, selling those same generic servos).

You're response came in while I was typing, you're missing my point, I can buy a generic servo and a speed reducer for less than your motor and it will achieve the same results. For me it's even cheaper because I make my own speed reducers. At one point I had a machine that could do one stitch every 3 seconds, it's not that difficult to achieve.

Edited July 5 by dikman