Suggestions for slowing down machine

[rockthecasbah121]

My wife and I own a dog collar business, and although we don't typically work with leather, our collars are relatively thick and we recently upgraded to an industrial machine after breaking numerous home machines.

We now have a Juki DDL-5550 with a servo motor. It goes through our collars with little effort, but we're having trouble controlling the speed. Even with the servo motor on the lowest setting and the pedal adjusted to not fully pull down the motor lever, the machine continues to take off of us when we're doing small runs (we have stitch lines that are only 2 inches in max length but have to go through two layers of collar). 

I've looked in to two possible alternatives- the reliable 6000SM which claims to be able to do one stitch at a time by tapping the pedal, and a superior 3-6-9 speed reducer pulley. Both items are pretty expensive, so I'd like some opinions on either one before I move forward. Is there one I should choose over the other? Should I go for both? Is there any issue with attaching the reducer pulley to a servo motor I should consider?

[Mark842]

Can't speak for the reliable 6000 but I have the superior 3-6-9 on three different machines. I can move the needle slower than you would possibly need to. Keep in mind you will need to pick up a belt and reposition your servo motor a little bit so you can line everything up

[keithski122]

You may be able to lengthen the arm that controls the motor and/or the pedal (not the joining rod), this should make the machine more controlable.I added an extra 3 inchs to both on my machine.

[Northmount]

Add a set of speed reducing pulleys.  You will have great torque and very slow speed if you size them right.  Can purchase a set, or build your own depending on your abilities and time.  There are lots of posts about using speed reducers here if you care to search for them.

Tom

[rockthecasbah121]

55 minutes ago, Mark842 said:

Can't speak for the reliable 6000 but I have the superior 3-6-9 on three different machines. I can move the needle slower than you would possibly need to. Keep in mind you will need to pick up a belt and reposition your servo motor a little bit so you can line everything up

Do you have any issues with the machine not coming to a quick stop with the pulleys being used? 

[rockthecasbah121]

32 minutes ago, keithski122 said:

You may be able to lengthen the arm that controls the motor and/or the pedal (not the joining rod), this should make the machine more controlable.I added an extra 3 inchs to both on my machine.

That's an interesting solution I had not thought of. I'll take a look at my motor when I get home to get an idea of how easy/hard it would be to replace. Do you notice any low torque issues when using this method? I know at the slowest speed I can get my machine to with very little pedal compression, I sometimes have to give the flywheel a nudge to get it going. 

[DrmCa]

Get a smaller pulley for the motor. Your servo probably came with the 3" pulley.

[keithski122]

Machine will act the same as before.All I did was use short lengths of angle to lengthen the arms.It all leverage and arcs.......the pedal has to move further between min and max making control beween the two less sensitive.

[Mark842]

2 hours ago, rockthecasbah121 said:

Do you have any issues with the machine not coming to a quick stop with the pulleys being used? 

No.

[dikman]

A decent speed reducer is probably the way to go if you already have a servo fitted. Couple that with the smallest pulley you can fit on the motor and you should get it to go much slower and have increased torque. You can make your own, but it's a fair bit of messing around.

I'm surprised that, being a servo, you can't get a slower speed out of it.