Juki 1508 balance adjustment method

[ArtD]

I’ve been running my Juki 1508 at higher speeds lately and me it seemed to me to have quite a bit of shake at the upper end. So I checked out the engineer’s manual for this machine. It calls for the balancer screw to be in line with the top cam screw (page 26). These weren’t aligned on my machine, so I made the adjustment but it only got rougher. So I kept moving the balance weight in small increments until the machine seemed to smooth out. It’s better now although not perfect, and I imagine there will always be some vibration in a walking foot machine. My question is this: Is there a proven methodology for determining the best position for the balance cam, or is it really just make incremental adjustments until it feels good?

I bought this machine new, so it’s not like someone was in the machine and set it up differently than the engineer’s manual. Is it possible the engineer’s manual is wrong? 
 

Thanks, Art

Edited November 4 by ArtD

[Northmount]

49 minutes ago, ArtD said:

I bought this machine new, so it’s not like someone was in the machine and set it up differently than the engineer’s manual. Is it possible the engineer’s manual is wrong? 

Moved your post to leather sewing machines.  This is where the machine guys hang out.

This is the best you can do unless you have a good knowledge of balancing procedures and the right diagnostic instrumentation.   You would need to do what is called a dynamic balance, measuring the static and couple components and calculating the weight changes and positions to add or subtract weight.  Not easy on a sewing machine.

[CowboyBob]

@ArtD I've sold alot of these over the years & never had a problem like this.If you haven't already you should try to lower the height the feet walk.

[ArtD]

Let me ask the question another way. Is it the balancer’s job to reduce vibration, or is it meant as a counterweight in the cycle of producing a stitch. In other words, if I position it to minimize vibration, and this position is different than what is spelled out in the engineering manual, am I introducing a problem?

[CowboyBob]

Another cause,the motor belt many of them have bulge where they join you can feel it with your finger.Or it could too tight.And since you moved the balancer you should try to put it back the where it was so the #1 feed cam & #1 balancer screw line up.

Edited November 12 by CowboyBob

[Northmount]

3 hours ago, ArtD said:

Is it the balancer’s job to reduce vibration, or is it meant as a counterweight in the cycle of producing a stitch.

A counterweight's purpose is to reduce vibration.  The counterweight is placed 180 degrees opposite to the unbalanced weight.