slow stitching speed

[BillyR]

buying a new machine and was wondering how to relate rpm to stitches per minute..if with a reducer the machine does say 100rpm slowest speed, does that mean 100 stitches per minute ?thanks

[garypl]

Should depend on sizes of the pulleys.  Best to go test the machine, if possible, so you can decide if it will sew slow enough for you.  I have a CB4500 and my normal speed is about 50 stitches per minute.

Gary

[Joon1911]

Billy, I know the following doesn’t actually answer your question but I think it relates.

I have a standard setup Cobra Class 4 which is basically the same thing as Gary’s CB4500.  If I recall the servo motor doesn’t tell you rpm in the settings, it goes from 1-25 maybe?  It’s been so long since I messed with it.  For the first month I set it at 3 or so until I gained comfort. That setting at its fastest was maybe 60-70 stitches per minute if I recall correctly.  Upon the suggestion of a mentor, I changed that setting to the highest and have never looked back.   I can stitch as slow as I want, maybe 1 stitch every 2-3 seconds to full bore just by the pedal engagement.  

I’d suggest this to anyone;  get used to controlling your motor not letting it control you. I wouldn’t want to switch back and forth all the time whenever I wanted to sew a belt or strap or fill bobbins.  That’s lost time and productivity.  

[garypl]

27 minutes ago, Joon1911 said:

Billy, I know the following doesn’t actually answer your question but I think it relates.

I have a standard setup Cobra Class 4 which is basically the same thing as Gary’s CB4500.  If I recall the servo motor doesn’t tell you rpm in the settings, it goes from 1-25 maybe?  It’s been so long since I messed with it.  For the first month I set it at 3 or so until I gained comfort. That setting at its fastest was maybe 60-70 stitches per minute if I recall correctly.  Upon the suggestion of a mentor, I changed that setting to the highest and have never looked back.   I can stitch as slow as I want, maybe 1 stitch every 2-3 seconds to full bore just by the pedal engagement.  

I’d suggest this to anyone;  get used to controlling your motor not letting it control you. I wouldn’t want to switch back and forth all the time whenever I wanted to sew a belt or strap or fill bobbins.  That’s lost time and productivity.  

That’s good advice Joon - now that I have been using my machine for awhile I will see how I do with bumping up the speed dial!

Gary

[Matt S]

11 hours ago, BillyR said:

buying a new machine and was wondering how to relate rpm to stitches per minute..if with a reducer the machine does say 100rpm slowest speed, does that mean 100 stitches per minute ?thanks

Yes the RPM of the balance wheel on the machine = SPM. Is that 100RPM what's quoted on the machine or the motor?

To calculate this from your motor RPM you have to know the ratio of the pulleys in your powertrain. A lot of upholstery-weight machines have around a 80mm pulley. So with a 40mm pulley on the motor (the smallest you can easily get) you're only getting a 2:1 reduction. The super-cheap servo on my upholstery-weight cylinder-bed machine starts at 500RPM so I had to fit a 3:1 reducer to get it under 250SPM. With the reducer I have it down to about 80SPM, which is pretty slow. Bonus with a reducer is that you get an equivalent boost in torque (punching power).

I find this calculator handy: https://www.blocklayer.com/pulley-belt.aspx

[Wizcrafts]

1 hour ago, Matt S said:

The super-cheap servo on my upholstery-weight cylinder-bed machine starts at 500RPM so I had to fit a 3:1 reducer to get it under 250SPM. With the reducer I have it down to about 80SPM, which is pretty slow.

You might want to think about changing servos to a Family Sew 550. I have that motor on my CB4500 and on my long arm Singer 139 walking foot machine. It starts at zero rpm and slowly increases with pedal motion. There is a knob on the front face of the motor that limits the top speed, or not. There are no sudden changes in speed.

[BillyR]

thanks boys for your responses..I ordered a techsew 2750 with servo and speed reducer so it sounds like I can be a stitch a second sewer with no problem..I just wasn't sure if the servo alone would let me do that so I added the reducer to make sure. I hope the high speed is still useable..As you can see, I know nothing

[JLSleather]

I never understood (and still don't) what is the perceived value of going SLOWER.  I've actually seen videos and articles of people going on about how SLOW they can sew.  Then with the other side of their mouth tell you it's expensive because it takes time!  So, some  amusing thoughts ...

• Would you pay more for a flight from Chicago to LA if the pilot agreed to go have as fast?
• When those boys show up to plow the snow from my drive, should I pay more to the fast guy, or the guy who takes a while?
• Does pizza cost more if it's here in 31 minutes or MORE?

Okay, that was only moderately fun.  But if you want to sew, including leather, ask Wiz where that video of his went -- where he was sewing straps (gun slings?) on a National machine... took almost as long as typing this (but not quite).

I have a pedestal machine, that i WOULD run up faster, except the base just isn't sturdy enough.  Servo set about 20 or so - for those who know what that means - but when you run it up a bit it isn't stable, even with the stand adjusted most of the way down.  Faster it goes, more it rocks... despite way too much time spent leveling, and leveling, and releveling ....

FORTUNATELY, if a speed reducer can be added, it can also be removed.  I DO understand not wanting to ruin a project you spent 10 hours tooling, but a plain strap of leather is what ... $10?  $15?  

 

[Sonydaze]

4 hours ago, Joon1911 said:

Billy, I know the following doesn’t actually answer your question but I think it relates.

I have a standard setup Cobra Class 4 which is basically the same thing as Gary’s CB4500.  If I recall the servo motor doesn’t tell you rpm in the settings, it goes from 1-25 maybe?  It’s been so long since I messed with it.  For the first month I set it at 3 or so until I gained comfort. That setting at its fastest was maybe 60-70 stitches per minute if I recall correctly.  Upon the suggestion of a mentor, I changed that setting to the highest and have never looked back.   I can stitch as slow as I want, maybe 1 stitch every 2-3 seconds to full bore just by the pedal engagement.  

I’d suggest this to anyone;  get used to controlling your motor not letting it control you. I wouldn’t want to switch back and forth all the time whenever I wanted to sew a belt or strap or fill bobbins.  That’s lost time and productivity.  

I agree, watching your machine amble down the easy parts to sew is a waste of time.  I can't envision someone wanting to pay more for your product just because you sewed it really slow.  

[Hockeymender]

Sewing speed is dictated by what is being done. I see all this about “why would anyone want to slow things down?”. Around here everything is sewn at the slowest speed possible. Precision work requires it. Hockey glove palms can be quite tricky to get placed and sewn properly, and if the machine was zipping along it would be a complete disaster for sure. Just my 2 cents worth. 

[Matt S]

3 hours ago, JLSleather said:

I never understood (and still don't) what is the perceived value of going SLOWER.

For me (whose tools all have to pay their way) it's about control and precise placement. I only go slow at starts and ends (especially backtacking), steps up/down for precise placement, sewing around curves and into square corners. My servo motors' pedals give 10 steps between the lowest and highest programmed speeds. I usually have the max speed set near the motor's maximum speed (4500RPM) -- tickle it for precision @80SPM, stomp it on the straightaways @750SPM. I'm not gunshy, I'm not claiming that slower production = better product, I'm not stretching my jobs to fill the gaps between coffee breaks. I pay myself. More product out the door = more pay. Having a slow machine speed available reduces the amount of handwheeling I have to do, and I sure can't handwheel at 80SPM. Can't hold onto the workpiece, press the reverse lever and handwheel at the same time either.

4 hours ago, Wizcrafts said:

You might want to think about changing servos to a Family Sew 550. I have that motor on my CB4500 and on my long arm Singer 139 walking foot machine. It starts at zero rpm and slowly increases with pedal motion. There is a knob on the front face of the motor that limits the top speed, or not. There are no sudden changes in speed.

Thanks for the recommendation Wiz. We have a smaller selection of servos this side of the pond, as we do 240ish volts @ 50hz out the wall. A better servo is on my wishlist, but it's a long list. This one only cost £100ish and came with a needle positioner.

[Sonydaze]

17 minutes ago, Hockeymender said:

Sewing speed is dictated by what is being done. I see all this about “why would anyone want to slow things down?”. Around here everything is sewn at the slowest speed possible. Precision work requires it. Hockey glove palms can be quite tricky to get placed and sewn properly, and if the machine was zipping along it would be a complete disaster for sure. Just my 2 cents worth. 

Hence the joy of a properly setup servo motor... sew the speed that the job demands. I sew more and more belts on my 441 clone (and belts aren't getting shorter..)  Sewing down the length of it is easy to guide so it's pedal to the metal, however sewing the tip of the belt is very visible when being worn and the servo allows me to get a stitch at a time if I want.  End of the day, I still want to get each item completed as quickly as possible.

[JLSleather]

34 minutes ago, Matt S said:

 I only go slow at starts and ends (especially backtacking), steps up/down ... around curves and into square corners....- tickle it for precision @80SPM, stomp it on the straightaways @750SPM....

That's what I'm talking about 

[JerseyFirefighter]

1 hour ago, Hockeymender said:

Sewing speed is dictated by what is being done. I see all this about “why would anyone want to slow things down?”. Around here everything is sewn at the slowest speed possible. Precision work requires it. Hockey glove palms can be quite tricky to get placed and sewn properly, and if the machine was zipping along it would be a complete disaster for sure. Just my 2 cents worth. 

Provided you can "feather" the pedal, I don't see why not leaving at max rpm is an issue for a 441 machine. I completely understand that no two people are alike, but messing around with settings mixed with your abilities is the best way to find a happy medium (or to leave the the motor maxed and use it when needed on those long belt runs).

 

I had heard another worker mention that running full rpm increases the marks of the presser foot/feet. While I dont suspect that is the case, and I have seen this topic and solutions suggested here... if anyone would like to chime in on the matter in terms of speed vs foot pressure it would be appreciated. 

[Hockeymender]

Guess this is all relevant if you are using a 441 type machine and sewing belts. I’m not using/ doing either. 

[JerseyFirefighter]

4 minutes ago, Hockeymender said:

Guess this is all relevant if you are using a 441 type machine and sewing belts. I’m not using/ doing either. 

You are correct. My apologies as the conversation quickly shifted to those machines. 

[Matt S]

1 hour ago, JLSleather said:

That's what I'm talking about 

Well that's your answer then: having a very low minimum speed is useful for doing the fiddly bits.

[Joon1911]

12 hours ago, garypl said:

That’s good advice Joon - now that I have been using my machine for awhile I will see how I do with bumping up the speed dial!

Gary

Gary,

I guess I see it as the benefits of versatility far outweigh the disadvantage of possibly putting a stitch where I don’t want it.  I’ve found that with experience it’s a non-issue anyway.  As Matt S. said earlier, the ability to instantly switch between 50spm to 750 and anywhere in between has become essential to me.  

[Joon1911]

3 hours ago, Hockeymender said:

Guess this is all relevant if you are using a 441 type machine and sewing belts. I’m not using/ doing either. 

I’ve always been curious about how gloves are sewn, do you use a post bed machine?

[Hockeymender]

5 minutes ago, Joon1911 said:

I’ve always been curious about how gloves are sewn, do you use a post bed machine?

No I use Pfaff 335 cylinder arm machines. If your interested there is a video showing the repalming process on my website: www.hockeymenders.com 

Edited March 15, 2018 by Hockeymender

[Joon1911]

Just now, Hockeymender said:

No I use Pfaff 335 machines. If your interested there is a video showing the repalming process on my website: www.hockeymenders.com 

Thanks Joe.  I’ll check that out!

Sorry for the thread hijack, my bad.  Return to normal broadcasting please.

[BillyR]

As I figured, you want to go as slow as you need to and as fast as you want to..Since I don't have my machine yet I was curious as to how slow it will go on the slowest setting. I am hoping for about a stitch a second..guess I'll find out soon. I ordered it with needle positioner....rookie move?

[dikman]

Not necessarily. I bought one 'cos it sounded like a good idea (being a newbie), tried it out but didn't really like it much - because I tend to sew slow there''s no real advantage in having it. For someone who sews fast, however, I can see where it could be quite useful. By all means try it out, who knows, it may suit your needs/sewing style.

[billybopp]

20 hours ago, JLSleather said:

I never understood (and still don't) what is the perceived value of going SLOWER.  I've actually seen videos and articles of people going on about how SLOW they can sew.  Then with the other side of their mouth tell you it's expensive because it takes time!  So, some  amusing thoughts ...

• Would you pay more for a flight from Chicago to LA if the pilot agreed to go have as fast?
• When those boys show up to plow the snow from my drive, should I pay more to the fast guy, or the guy who takes a while?
• Does pizza cost more if it's here in 31 minutes or MORE?

Okay, that was only moderately fun.  But if you want to sew, including leather, ask Wiz where that video of his went -- where he was sewing straps (gun slings?) on a National machine... took almost as long as typing this (but not quite).

I have a pedestal machine, that i WOULD run up faster, except the base just isn't sturdy enough.  Servo set about 20 or so - for those who know what that means - but when you run it up a bit it isn't stable, even with the stand adjusted most of the way down.  Faster it goes, more it rocks... despite way too much time spent leveling, and leveling, and releveling ....

FORTUNATELY, if a speed reducer can be added, it can also be removed.  I DO understand not wanting to ruin a project you spent 10 hours tooling, but a plain strap of leather is what ... $10?  $15?  

 

Would you pay more for a flight from Chicago to LA if the pilot agreed to go have as fast?

  Yes.  IF it meant that we'd actually arrive at LA and do so safely 

When those boys show up to plow the snow from my drive, should I pay more to the fast guy, or the guy who takes a while?  

  Yes.  If the guy that takes awhile does a good job of it when the fast guy doesn't.

Does pizza cost more if it's here in 31 minutes or MORE?

   Yes.   And I frequently do pay more and wait a bit longer when I get pizza from the local mom and pop shop.  It's FAR better than the fast pizza from Domino's, and hence worth the money and the wait.

The point of going very slowly when sewing is to get the precision needed to put a stitch exactly where you want it - for example at exactly the point of that English point belt end.  

I don't yet sew leather by machine, since I have no space for a big sewing machine.  I do, however, occasionally hem pants and repair clothing using my "domestic" sewing machine.  When it comes to the tricky bits and turns I frequently use just the handwheel to get things exactly as I want them.  Even when sewing longer stretches, I don't go at full speed since full speed is beyond my skills to control.

So, if one has the skills to sew at top speed then that's awesome.  But for most folks sewing leather, I suspect that the control afforded by going VERY slow at the bottom end of the speed range more than offsets the loss of speed at the high end.

- Bill

[Constabulary]

Amen!