Stitchers, Reducers, And Motors.....oh, My!

[TwinOaks]

RANT ON:

Hi everyone,

This morning I spent some time browsing the web and doing some research. I found a youtube vid promoting the MC-SCR system for their sewing machines. The jist of the video is that their MC-SCR is the cat's meow of sewing machine motors- ESPECIALLY if you need slow speed control....and servo motors suck eggs. They demonstrated this by showing a SERVO MOTOR , running at slow speed, that had such low torque that a single finger placed on the pulley could (and did) stop the motor's rotation. The motor was then demonstrated on a 111, with direct drive. Then the whole shebang was contrasted showing their MC-SCR. Guess which one performed best.

I'd like to point out a few things about the video for folks who are researching leather sewing machine components. First, the video NEVER states whether the servo motor in question is a DC or AC motor. In fact, the motor plate is never seen, which kinda prevents the viewer from having some critical info. Second, they are running on a direct drive to the (small-ish) balance wheel on the 111 with what looks like a frayed bungee cord.

Most of the machines advertised here as "leather sewing machine" have some sort of speed reducer (which increases torque), and the major two -Artisan and Cobra- specify DC motors, which makes a huge difference.

I ask that some of our sewing machine experts chime in on the design differences, and also our members that own and use the DC motors on their machines. I've seen the old Artisan video showing dang slow sewing on what looked like about 16 oz of leather. I get really frustrated seeing this type of advertising, where the information isn't so much wrong, just incredibly incomplete, and it encourages the wrong impression by an uninformed person. Any one else?

rant off

[gtwister09]

Not sure why you didn't include the references for people to look at.... Found them and included them below.

This gives the cost and other specs. The specification state that it is a 120V DC motor that runs through the microcontroller at 110VAC. Here's the link for the video and some technical specifications.

MC - SCR [sailrite]

Regards,

Ben

[bruce johnson]

Mike,

I expect I have DC servos on my two machines, but don't know for sure. My experience with servo motors. I had an Adler 205-64 with a clutch motor, smally motor pulley, and speed reducer. At that time about the only really controllable motors seemed to be the Efka motos = $$$$$$. When the servos got sort of more available about 5-6 years ago I swapped out the clutch for the servo. Way more control and at least for me seemd like more torque. With the clutch I had to feather the wheel to prevent the jump when I started. I got into the habit of having my hand on the wheel to control the starts and slowdowns. The first thing I noticed about the servo was it threw my hand off starting out. Same with slowing down for a corner. The control was enough I didn't need to have my hand up there ayway, just a habit to break. I got a 2000 and at that time still had a choice of clutch or servo - no decision. I went with the servo and speed reducer setup. I can dial it from a stitch every 3 seconds to pretty fast running down a rein. When I ordered the 1245, Ron said I could probably get by without a speed reducer. I wanted slow speed control more than fast speed and went with the reducer anyway. The speed reducer on the 1245 makes it easy to just pop the belt off by hand and tip the head back to get underneath for maintenance too. I don't need to get the wrench and slide the pulleys. Most of my sewing on the 2000 is from gussets in cases and bags where In need the cylinder arm and special plates up to 2-3 layers of skirting on the flat. The 1245 does all the strap work and most of the flat stuff that won't exceed the capacity. Neither of my machines lack any torque.

My only complaint is this - WHY can't they make the speed control dial remote so that it can be mounted on the table by the motor switch instead of part of the motor? When you change top end speed, you have to crawl under or behind to change the dial. Just put it there where it's handy. That is my mini-rant.

[Art]

Hi Bruce,

One of the reasons is that only a rare few if the sewing machine purveyors do any leatherwork. Also, they are extremely hardheaded, and don't see why we would need the control up on the desk. Btw, these controls are available, but unfortunately none of the purveyors are good Chinese speaking folks and haven't a clue how to source anything. Also, none of them have engineering degrees and the kind of imagination that comes with it. It doesn't help them much when the customers and the competition are pressing for lower and lower prices. Another point is why should someone do (time is money) the engineering and then have the rest of the machine sellers copy them. The Chinese factories are loyal only to the Yuan (dollar), and will sell to anyone who knows how to transfer money. So one guy has to do the engineering and take the risk and the rest ride for free. Any wonder why we don't see more innovation?

Art

Mike,

I expect I have DC servos on my two machines, but don't know for sure. My experience with servo motors. I had an Adler 205-64 with a clutch motor, smally motor pulley, and speed reducer. At that time about the only really controllable motors seemed to be the Efka motos = $$$$$$. When the servos got sort of more available about 5-6 years ago I swapped out the clutch for the servo. Way more control and at least for me seemd like more torque. With the clutch I had to feather the wheel to prevent the jump when I started. I got into the habit of having my hand on the wheel to control the starts and slowdowns. The first thing I noticed about the servo was it threw my hand off starting out. Same with slowing down for a corner. The control was enough I didn't need to have my hand up there ayway, just a habit to break. I got a 2000 and at that time still had a choice of clutch or servo - no decision. I went with the servo and speed reducer setup. I can dial it from a stitch every 3 seconds to pretty fast running down a rein. When I ordered the 1245, Ron said I could probably get by without a speed reducer. I wanted slow speed control more than fast speed and went with the reducer anyway. The speed reducer on the 1245 makes it easy to just pop the belt off by hand and tip the head back to get underneath for maintenance too. I don't need to get the wrench and slide the pulleys. Most of my sewing on the 2000 is from gussets in cases and bags where In need the cylinder arm and special plates up to 2-3 layers of skirting on the flat. The 1245 does all the strap work and most of the flat stuff that won't exceed the capacity. Neither of my machines lack any torque.

My only complaint is this - WHY can't they make the speed control dial remote so that it can be mounted on the table by the motor switch instead of part of the motor? When you change top end speed, you have to crawl under or behind to change the dial. Just put it there where it's handy. That is my mini-rant.

[TwinOaks]

Not sure why you didn't include the references for people to look at....

Computer hung up when I went to insert the link, and I got sidetracked on other things (honey-do-list). Here's the link to the video: http://www.youtube.com/watch?v=tMwXZYaJGBE&feature=related. My rant about not giving motor info is directed towards the servo motor in question. I think even the old clutch motor on my viking would probably out perform a 1/10 hp ac servo, run with a loose belt.