Juki LZ 586 questions

[Nairbg]

I have just purchased my first industrial type sewing machine. It needs a little attention and I need some direction.

First, on the back of the main casting toward the drive side there is a small vertical mounting boss cast in. It has 2 threaded holes, one over the other. I cannot determine the size or thread pitch of those holes. They are close to 6mm but they are finer than the expected 1mm tgread pitch. Anyone know what this size/pitch is?

Second, my information to date suggests that a #18 needle and Tex70 thread are the largest that this machine can handle. I'd like to go heavier. Has anyone any experience/information on going heavier with this machine?

[kgg]

4 hours ago, Nairbg said:

First, on the back of the main casting toward the drive side there is a small vertical mounting boss cast in. It has 2 threaded holes, one over the other. I cannot determine the size or thread pitch of those holes. They are close to 6mm but they are finer than the expected 1mm tgread pitch. Anyone know what this size/pitch is?

Those are for mounting the upper belt cover and they are 15/64-28 L=10.

My understanding is that machine is a high speed drop feed zig zag machine for fabric installing a larger needle will probably cause problems. What are you planning on sewing????

kgg

[Nairbg]

I was planning to sew car seat upholstery and some canvas.  Do you think it will sew Tex90 thread with a #18 needle?

Edited 13 hours ago by Nairbg

[kgg]

21 minutes ago, Nairbg said:

I was planning to sew car seat upholstery and some canvas. 

This would definitely not be my choice for sewing upholstery or canvas. You really need at least a walking foot machine. My understanding this machine is really only designed for thin fabric.

21 minutes ago, Nairbg said:

Do you think it will sew Tex90 thread with a #18 needle?

An #18 needle is only rated for V69 (T70) max thread. Here is a good reference chart for needle size vs thread size ( https://www.tolindsewmach.com/thread-chart.html ).

kgg

 

[friquant]

15 hours ago, Nairbg said:

Second, my information to date suggests that a #18 needle and Tex70 thread are the largest that this machine can handle. I'd like to go heavier. Has anyone any experience/information on going heavier with this machine?

In general, you may be able to sew with bigger thread than what a manufacturer states. But be prepared to accommodate the machine!

1. The needle + top thread needs to fit through the needle plate. (You can adapt the size of the hole as long as you polish it after.)

2. At some point, you will max out the tension adjuster for the needle thread. To get a balanced stitch with such limitation, you may need a bigger needle (makes a bigger hole, which is easier to pull the thread through when locking the stitch.) Also lessen the bobbin case thread tension to accommodate. (Thicker thread gives more bobbin tension for the same adjustment.)

Let us know what you discover!