Machine Selection For Handbags and Backpacks

[moneypit]

I've been making backpacks and small bags with various nylon fabrics for about 3 years now and want to expand into using leather in my projects. During this time, I've also been designing my own patterns.

After reading in The Leatherworking Handbook, I saw the recommendation to use 5-6oz leather for bags. I'm primarily focused on veg tanned, but may step into chrome tanned as well.

I want to make laptop bags, backpacks (20L or less capacity), and "luxury" handbags/purses.

At the moment, I am trying to consider which machine is appropriate for my needs. Based on comments that I have read on the forum, I am seeing a recommendation for tex 138 thread in these applications.

In the running of potential machines are:

- Juki LS-1341

- Juki LS-2342

- Adler 669 Eco

- Adler 869 Eco

- And potentially the Alder 969 Pure for kicks and giggles

Making bags is a hobby that I really enjoy and don't mind putting funding into for new machines. I also really love machines in general.

As of right now, I can't think of a time where I would need to sew more than 4 layers of 6 oz veg tan at a time.

I would greatly appreciate any insight on the matters of leather thickness, thread size, machine choice, etc. as this is new territory to me from the nylons that I'm used to working with.

[kgg]

15 minutes ago, moneypit said:

In the running of potential machines are:

Nice brand name list. Expensive but very nice.

I can't speak to the Alder machines other then parts and accessories can be expensive / limited.

What my concerns would be with the Juki's are:

I like my machines simple, machine, belt, motor and maybe a speed reducer. The Juki LS-2342 would be out of the running for me as it has an integrated drive motor, needle limit of 140 unless you go with the LS-2342H or LS-2342h-7-OB and uses the 134 needle system. The Juki LS-1341/1342 use the more common 135 needle system and can accept 180 needles. Motor replacement down the road could be expensive and does not allow for a speed reducer option.

25 minutes ago, moneypit said:

As of right now, I can't think of a time where I would need to sew more than 4 layers of 6 oz veg tan at a time.

That totals about 24 oz of leather which means about 9.6mm (about 0.38"). That is within the approximate 1/2"+ ability of the Juki LS-1341/1342.

Since you are planning on a large outlay of cash I would suggest making a trip to a dealer and test driving with your stuff a couple of machines.

Here is a couple of links so you can compare the Juki specs:

https://www.juki.co.jp/industrial_e/admin/pdata/filedata/332/ls1340.pdf

https://www.juki.co.jp/industrial_e/admin/pdata/filedata/330/ls2342.pdf

kgg

[moneypit]

22 minutes ago, kgg said:

Nice brand name list. Expensive but very nice.

I can't speak to the Alder machines other then parts and accessories can be expensive / limited.

What my concerns would be with the Juki's are:

I like my machines simple, machine, belt, motor and maybe a speed reducer. The Juki LS-2342 would be out of the running for me as it has an integrated drive motor, needle limit of 140 unless you go with the LS-2342H or LS-2342h-7-OB and uses the 134 needle system. The Juki LS-1341/1342 use the more common 135 needle system and can accept 180 needles. Motor replacement down the road could be expensive and does not allow for a speed reducer option.

That totals about 24 oz of leather which means about 9.6mm (about 0.38"). That is within the approximate 1/2"+ ability of the Juki LS-1341/1342.

Since you are planning on a large outlay of cash I would suggest making a trip to a dealer and test driving with your stuff a couple of machines.

Here is a couple of links so you can compare the Juki specs:

https://www.juki.co.jp/industrial_e/admin/pdata/filedata/332/ls1340.pdf

https://www.juki.co.jp/industrial_e/admin/pdata/filedata/330/ls2342.pdf

kgg

You're right, I meant to specify the LS-2342H specifically.

I'm right there with you on that integrated servo motor. Last I talked with my dealer, he was saying it would be about ~600 USD for the part versus ~200 USD for an external servo.

Am I on the right track with using a tex 138 in this application, or is there a need to consider something heavier like tex 207 as well?

[kgg]

36 minutes ago, moneypit said:

Am I on the right track with using a tex 138 in this application, or is there a need to consider something heavier like tex 207 as well?

My take on the Juki thread spec. Juki rates their machines thread size (top and in the bobbin) to be used in the thickest material the machine is rated for not based on what the size of the thread that fit in the max size needle it will accept.

Example: Juki LS-1341 is rated for V138 thread and will accept a #24 (180) needle. The #24 needle will take V207 thread yet the machine is only rated for V138 thread. Depending on how thick and tough the material is you could use V207 a lot of times. It appears that some clones rate their machine based on the needle being able to accept V207.

Also if you are looking for that little extra pop V207 would give you maybe able to get away with V207 as a top thread and V138 as the bobbin thread but the strength of the seam will be that of the smaller V138 thread. Once you go consistently at V207 or at the max thickness of the Juki LS-1341 then you are at the cross over point into a Class 441 machine, Juki TSC-441. The cost of a Juki TSC-441 is for most prohibitive at around $8,000 USD and that's why the clones are the option for most at around $3,000 USD. The major drawback of the Class 441 is the size of hole the needle makes as compared to that of the Juki LS-1341. Think of a 3" finishing nail hole size.

kgg