Juki LS-1341 Needle size/ range confusion?

[RFRLEATHER]

Hi everyone, I’m looking to pull the trigger on my first industrial machine: a refurbished Juki LS-1341 from a local seller. It’s fully overhauled with a digital servo, needle positioner, and compact table.

My primary focus is leather bags mixed with outdoor technical fabrics (Cordura, ripstop, canvas) and lightweight liners. I plan to keep my domestic HD machine for very light work, but I want this Juki to handle the 'medium-to-heavy' range.

My Confusion:

I’m seeing a lot of conflicting information regarding the needle size compatibility for the LS-1341, particularly on the lower end:

• Juki Junkies: States a range of #19 to #24, mentioning that anything smaller (like an #18) requires re-timing.

• Other Third-Party Dealers: Some list the range as #16 to #24 without mentioning any timing modifications.

• Cobra Class 26 (Clone): Rated for #12 to #25, even though it's the same basic design.

My Questions:

1. Lower Limit: Can I reliably run a #16 (Nm 100) or #18 (Nm 110) needle for sewing Tex 45 or Tex 70 thread through Cordura/liners without skipping stitches or hitting the hook?

2. Needle Systems: Does the choice between 135x17 (fabric) and 135x16 (leather) impact the timing tolerances for smaller sizes?

3. The 'Re-timing' Myth: For those of you with an LS-1341, have you had to physically move the hook closer to the needle (adjusting the needle-to-hook clearance) just to drop down to a #18?

I really want a 'do-it-all' machine for bags, but I'm worried that if I'm forced to stay at #19 and above, I'll be punching 'drainage holes' into my lighter technical fabrics. Any insight from long-term 1341 users would be greatly appreciated And if there are any recommendations for other machines that might fit my needs better im all ears!

[kgg]

8 hours ago, RFRLEATHER said:

My Confusion:

I’m seeing a lot of conflicting information regarding the needle size compatibility for the LS-1341, particularly on the lower end:

• Juki Junkies: States a range of #19 to #24, mentioning that anything smaller (like an #18) requires re-timing.

• Other Third-Party Dealers: Some list the range as #16 to #24 without mentioning any timing modifications.

• Cobra Class 26 (Clone): Rated for #12 to #25, even though it's the same basic design.

Here is a link to the actual Juki LS-1341 brochure which will give you the definitive comparison on all specs for the 1340 series machines.  ( https://www.juki.co.jp/industrial_e/admin/pdata/filedata/332/ls1340.pdf ).

8 hours ago, RFRLEATHER said:

1. Lower Limit: Can I reliably run a #16 (Nm 100) or #18 (Nm 110) needle for sewing Tex 45 or Tex 70 thread through Cordura/liners without skipping stitches or hitting the hook?

If the machine was new yes. With used machines it could be iffy on the smaller thread sizes which will be an individual machine ability depending wear of internal parts typically whether it was a hobbyist machine or a machine that was used in a commercial environment. 

9 hours ago, RFRLEATHER said:

2. Needle Systems: Does the choice between 135x17 (fabric) and 135x16 (leather) impact the timing tolerances for smaller sizes?

No, but I don't use threads less then V92. The only then is you have to change your top thread tension and bobbin thread tension when going from thread size to another, when you change to a different spool of thread, thread type and even color. 

 

8 hours ago, RFRLEATHER said:

I really want a 'do-it-all' machine

Not going to happen that is why a lot of use have more then one machine. Machines for the most part setup to basically do one function. 

My thoughts:

i) The Juki LS-1341 is basically a functional Juki DNU-1541S in cylinder arm form. The main concern I would have with the LS-1341 in thin material is the material being sucked down into the feed dog as the hole is fairly large. This may not be the best machine for your needs and maybe a Pfaff 335 or clone or a post bed machine would be better options as they are inclined towards smaller thread sizes.

ii) How thick is the thickness material including folded over seams that you want / need to sew with what size of thread??

9 hours ago, RFRLEATHER said:

It’s fully overhauled with a digital servo, needle positioner, and compact table.

You really need to ask what was overhauled internally and externally for the machine, like timing belt, bushings, thread tensioner, thread guides, etc.  

What is the asking price for the machine. 

 

kgg

 

 

[RFRLEATHER]

9 hours ago, kgg said:

Hey Kgg, thanks for the reply! I want to be clear that i don’t expect this to sew ultra lite fabrics and i would use my domestic machine for those items. For example today im working on some equipment covers that are 4-6 layers of 200d nylon. I am also sewing 3mm neoprene and ripstop padded equipment bags ( trying to and failing) My domestic machine is struggling hard with both these tasks. This would be an example of the lighter end I would want to use on this machine. On the heavy end im sewing leather bags 4-6mm at the seams.

Here is a link to the actual Juki LS-1341 brochure which will give you the definitive comparison on all specs for the 1340 series machines.  ( https://www.juki.co.jp/industrial_e/admin/pdata/filedata/332/ls1340.pdf ).

Thanks! I did see this brochure on some of the reseller websites which is where i saw it was able to sew #16 needles I didnt realize it was from Juki so this is good. 

 

9 hours ago, kgg said:

If the machine was new yes. With used machines it could be iffy on the smaller thread sizes which will be an individual machine ability depending wear of internal parts typically whether it was a hobbyist machine or a machine that was used in a commercial environment. 

Understood, wear and tear can affect tolerances making it harder to sew smaller thread and needles. 

 

9 hours ago, kgg said:

No, but I don't use threads less then V92. The only then is you have to change your top thread tension and bobbin thread tension when going from thread size to another, when you change to a different spool of thread, thread type and even color. 

Understood, it can be a pain to change needles and thread.

 

9 hours ago, kgg said:

Not going to happen that is why a lot of use have more then one machine. Machines for the most part setup to basically do one function. 

I am grounded in reality that no machine is a do all machine but im just trying to hit the sweet spot for my needs. This is a hobby for me with no actual deadlines so having to make some tweaks throughout a project to make the machine be as versatile as possible is ok with me. 

 

9 hours ago, kgg said:

My thoughts:

i) The Juki LS-1341 is basically a functional Juki DNU-1541S in cylinder arm form. The main concern I would have with the LS-1341 in thin material is the material being sucked down into the feed dog as the hole is fairly large. This may not be the best machine for your needs and maybe a Pfaff 335 or clone or a post bed machine would be better options as they are inclined towards smaller thread sizes.

Ok, I have watched lots of videos of people sewing similar items to what i am sewing to want to sew on a 1541 as well as some ladies sewing bags of medium weight materials on the 1341 so if the machines are the same then there is a good chance it could work well for me. I will look into the Pfaff but im not sure a post bed would be best for me  i will be mounting a flat bed for when i work on smaller leather goods and larger bag panels. I mentioned above that i dont plan on sewing ultra lite weight fabrics on this machine mainly heavier layered nylons and canvas in conjunction with leather.    

 

9 hours ago, kgg said:

You really need to ask what was overhauled internally and externally for the machine, like timing belt, bushings, thread tensioner, thread guides, etc.  

Ok, i will double check with the seller on these items.

Thanks again for your reply, i feel like i have a better understanding of the needle range and what’s possible.