Juki PLC-1690 High Post Bed Thread Question

[NickPol]

I am looking at industrial high post beds and came across this Juki Model. The thread size in the manual states #30 ~ #8 (Japanese yarn count), needle size Schmetz 134-35(R). Is there a comparison for this thread size to Tex? I tried looking a conversion chart up but have been unable to find anything that says Japanese yarn count. I feel like I am missing something here and the answer is right in front of my face. Any help is appreciated. We typically use a T135 thread. 

Thanks again. 

[Wizcrafts]

The Cotton Yarn numbers of #30 ~ #8 roughly correspond to bonded Tex sizes 70 through 210. Due to the totally different materials used, the sizes don't translate as accurately as measurements for cotton, or polyester, or rayon thread. There is a thread size comparison chart that includes cotton yarn equivalents on A&E Thread. There is no cotton yarn number comparison within the bonded nylon and bonded polyester groups. My best guess it that your T135 thread would be about the same diameter as #12/3 cotton. But, cotton is much lighter than nylon.

[kgg]

14 hours ago, NickPol said:

I tried looking a conversion chart up but have been unable to find anything that says Japanese yarn count.

Thread Sizing standards can drive you down the rabbit hole that is for sure. For the less commonly used thread sizing the easiest way to determine what the machine can handle is by the range of needle sizes a machine can accommodate and from there work backwards. A rule of thumb with Juki specifications is their machines are able to handle sewing thread of the same size in both the bobbin and the needle for sewing thick materials less one thread size of the max needle size.

The needle specification for the Juki PLC 1690 is for a  SCHMETZ 134×35R Nm100～Nm140 (Standard Nm120) with a 120 (#19) needle recommended and probably supplied. I used the spec from the Juki site for this machine ( www.juki.co.jp/industrial_e/products_e/lether_e/postbed_e/detail.php?cd=PLC-1690_PLC-1691_E).

That relates to a needle range of a #16 to a # 22 needle so from that I conclude it will sew thick materials using V46 (T45) to V92 (T90) thread. For thinner materials the range would be V69 (T70) to V138 (T135). With it's sweet spot thread being V92 (T90).

I guess it will depend on the toughness and thickness of what you want to sew.

kgg

Edited July 6, 2022 by kgg
spelling

[ljk]

In  my beginning years as a upholster we used cotton thread the size was 16-4 (about tex 105) and 24-3(about size 69) things were rapidly changing to nylon thread, staple guns vs spitting tacks. Most machines where 155 and 16-188.