What Exactly Is An "eps" (Electronic Positioning System)?

[Johanna]

What Exactly is an EPS?

Cobra Steve, Leather Machine Co., explains what an EPS (Electronic Positioning System) is, and how it can help you do a better job sewing leather. Be sure to watch the video too!

The EPS works by means of the electronic synchronizer which senses the position of the hand wheel as it rotates around its 360 degree cycle. There are two key points in this cycle. The first key point is when the needle has penetrated through the fabric and has come back up just enough for the machine’s hook to catch the loop formed by the thread. The second key point is when the needle and the take-up lever are at their highest points, which is when the stitch cycle is complete. The timing of these two stopping points is set at the factory by an expert mechanic. When you remove your foot from the actuating foot pedal, the sensor on the end of the upper main shaft can tell where the machine’s needle is in the stitch cycle. The needle position motor then advances and stops the machine at the next “needle down” position. The second stopping point, or the “needle up” position, is when the stitch cycle is complete so that you may remove your work from under the presser foot. To get the machine in this position, just push your heel down on the front of the pedal.

[Massive]

Perhaps this would be a place to put info on how to install this system. I got one on my cobra 4, and the basic plug and play instalation is pretty obvious, but it isn`t working as on the video. Probably something simple, maybe a programing thing on the motor. to recognize the eps is there. Great machine so far.

[BevJones]

Just call Cobra Steve, he will help you. Their service is top notch!

[Leather by LOU]

where is the video?

[Anne Bonnys Locker]

There are different types of Servo motor so keep in mind that these instructions only apply to one brand.

[SantaFeMarie]

If anyone is still monitoring this thread: the link in the OP is broken.

[venator]

Any way to add one of these to my Adler?

[Constabulary]

Depends on what accessories (screws + adapters) come with the motor but usually it is possible. Which Adler machine do you have?

[venator]

I have a 467 from Nick-o-Sew

[Constabulary]

The top shaft should have a internal thread so it depends if the servo motor comes with the right screw or not. Usually they come with 2 different threaded screws.

[Darren Brosowski]

Recently I had a 441 set up with a good quality clutch motor, 40mm pulley and no speed reducer. About a dozen saddlers played with the machine and all found it to have great control.

Most saddlers I talk to with 441's have disconnected the EPS if they can.

Steve, this is not a criticism of your setup on your machines, I am just pointing out the feelings of Australian saddlers. Keep in mind that most of these guys were taught on a Pearson 6.

[Hardin]

There is nothing like a needle positioned motor. I would never be without one. I have a Mitsubishi fully programable & computerized which costs about $900.00. Its worth every penny. 

[Haderimouve]

I have a Adler 467 that runs perfectly with the 750W Jacksew servo motor with  needle positioner available at www.college-sewing.co.uk  (But for sure also sold in the US).

I added an aluminium attachment that I made on my lathe for the Needle positioner BUT in the box there is a teflon piece that you can use as well and screw it at the end of your hand wheel , you just have to use a longer allen screw. 

https://www.college-sewing.co.uk/store/JK-561A-1-220V-750W-1-HP-SERVO-MOTOR-WITH-NEEDLE-POSITION

I completed optimizing the system in turning a smaller 40mm pulley for using it instead of the 75 mm delivered with the moto : I'm very happy with it ! The needle positioning when you 've tried it once, impossible to go behind ...

Edited April 26, 2017 by Haderimouve

[Wonderboy]

Hi.  Newbie here.

I'm considering purchasing either the Cobra Class 4 or the Cowboy CB4500 and wish to know how useful really is the ENPS?  I mean considering how slow these machines can sew I'm just not sure if it is a genuinely useful feature or just simply marketing.

I am leaning towards the CB4500 mainly due to it being about AU$600 cheaper (here in Australia), it's aesthetics (I don't like the brown look of the Class 4), and the stainless needle plates and feet.

[Wizcrafts]

14 hours ago, Wonderboy said:

Hi.  Newbie here.

I'm considering purchasing either the Cobra Class 4 or the Cowboy CB4500 and wish to know how useful really is the ENPS?  I mean considering how slow these machines can sew I'm just not sure if it is a genuinely useful feature or just simply marketing.

I am leaning towards the CB4500 mainly due to it being about AU$600 cheaper (here in Australia), it's aesthetics (I don't like the brown look of the Class 4), and the stainless needle plates and feet.

I use a CB4500 and can tell you with full confidence, that if you get one powered by a Family Sew motor, you will not need an EPS system to position the needle up or down. I can move the needle so slowly I can watch grass grow.

[Wonderboy]

17 hours ago, Wizcrafts said:

I use a CB4500 and can tell you with full confidence, that if you get one powered by a Family Sew motor, you will not need an EPS system to position the needle up or down. I can move the needle so slowly I can watch grass grow.

Thanks for replying Wiz.  Very helpful.

Sorry, can I please confirm is the Family Sew motor standard or extra? If extra what do the cost approximately?

[Russ498]

I see that this system is available on any Cobra Machine.  How much extra is it on a class 3 or class 4 machine?  the website doesn't give prices or specs.

[brmax]

I would pass on the positioner. At least on majority brands or types people get. 

The position part is a great advantage in many cases, but! In its function it can and does many times make two stitches.

The class 4 and cb4500 have bigger handwheel pulley so provide an even slower ratio than the upholstery class sizes with reducers of either style. 

 

Have a good day

Floyd

[DavidMillsSaddlery]

Would one of these work on a Singer 31-15 and a 153w103?

Edited April 14, 2019 by turbotexas

[Matt S]

4 minutes ago, turbotexas said:

Would one of these work on a Singer 31-15 and a 153w103?

No reason why not. I have one on my Seiko LCW-8, which is an updated version of the 153w. Biggest problem will be in fingering out how to fabricobble the sensor onto those machines. They were built well before such things were common. The sensor attaches to the handwheel by a little hub that's supplied in the kit. You unscrew the screw that holds the handwheel in place. The kit comes with a couple longer screws in common threads, so you screw the hub onto the handwheel through the hole left by the screw. There's some L-shaped screws which thread into a hole next to the handwheel, which prevent the sensor body from rotating. If these screws don't fit your machines you'll have to get out the calipers and start getting creative.

[George1520]

On 4/14/2019 at 8:20 AM, turbotexas said:

Would one of these work on a Singer 31-15 and a 153w103?

it will not work on any machines that have the stich length knob at the back of the flywheel. Singer w 111 type machine. I purchase one that has the sensor installed. The way they did it they machined the flywheel flat  and tap 3 screw holes for the sensor. Before they install it they cut the stich regulator and shoved in the hole. Basically  the machine is set to only one stich length 

[Matt S]

In theory a 1-signal NPS could be replaced with a microswitch or IR notch sensor positioned to trigger at the apex of the take-up lever.

[George1520]

On 10/6/2019 at 4:01 PM, Matt S said:

In theory a 1-signal NPS could be replaced with a microswitch or IR notch sensor positioned to trigger at the apex of the take-up lever.

It is basically a simpler version of the computer mouse. An optical switch that outputs twice for one flywheel rotation. One for the needle up and one for needle down.  If you replace it with micro switches you will need two. Otherwise it will work every other time, at least in theory.

[Matt S]

36 minutes ago, George1520 said:

It is basically a simpler version of the computer mouse. An optical switch that outputs twice for one flywheel rotation. One for the needle up and one for needle down.  If you replace it with micro switches you will need two. Otherwise it will work every other time, at least in theory.

Not all NPS sensors are the same. I'm sure that some have an optical rotary encoder but I've taken apart several low-end NPS units and found them to be a hall-effect sensor with a small magnet on the rotor wheel. Essentially all they do is provide a logic signal when the magnet passes (hi or lo depending on the brand). Easily replicated with many different off-the-shelf sensors.

I suspect that Jack servos count the number of motor revolutions between NPS signals, then divides by two to extrapolate for the "other" position. The ESDA servo I have doesn't do this, and have terrible granularity on the throttle.

[FDC]

I added one on my Techsew 5100 as a Chinese import (shame) EPS was cheap cheap. You have to adjust your servo settings and there’s not a lot of readily available info out there but you can do it. Was it worth it on a slow machine like mine? Sometimes. Would I recommend it to someone else? Acquiring knowledge costs money and time, in this case the knowledge came at a reasonable price so yeah, try it.