Needle system conversion on CB3200

[Damas]

Hello,

I would like to do a conversion on my CB3200 from 794 needle system to 328. The reason why is the following :

- 328 needles are cheaper, more easy to find and available in a variety of sizes that are currently no more available in 794 system (nothing under 160 in LR points)
- CB3200 is not maint to sew heavier than 15mm, so longer needles such as 794 are not really an advantage here

Did I missed something or this conversion would only be avantageous to me ? And what other steps would be necessary apart from lowering the needle bar ? And would I lost the timing by doing so ?

Thanks in advance for your answers
 

[Constabulary]

The specialty on the system 328 needles is that depending on their size they come with different shaft diameter. IIRC the 794 has 2.5mm no matter the needle size.

Edited November 4, 2024 by Constabulary

[Damas]

Very good point @Constabulary, I didnt know, I will have to check that on the sizes I'd like to use (120-130-140)

[kgg]

4 hours ago, Damas said:

And what other steps would be necessary apart from lowering the needle bar ? And would I lost the timing by doing so ?

Yes you will not only have to make the needle bar adjustment but also a timing adjustment and a hook to needle adjustment. If you use a different diameter needle then it was designed for then the needle will sit more to the left of the hook and if the diameter varies by size like @Constabulary has mentioned then you maybe constantly doing hook to needle timing adjustments. You are looking for 120/130/140 needles which equates to using V92 thread.

Why not save all the fooling around with converting to a different needle system and convert to using a larger thread size, V138?

The cost of a 10 pack from the thread exchange for 794 size 160 LR point is $12.99 (~13 cents each).

The cost of a 10 pack from the thread exchange for 328 size 140 LR point is $11.29 (~11.3 cents each).

For me the less then the two cent saving would not be worth the associated conversion headache.

kgg

 

[Damas]

I do get your point, but I am doing fine bridlework, all by hand, saddle stitching french style so far.

In order to be more competitive, I would like to extand my price range and offer machine sewn articles without changing the overall look and style of my production

This can only be achieved using more light thread and needle association

CB3200 by design accepts smaller needle sizes, 794 is available down to 110-120 range but not in LR point

[kgg]

8 minutes ago, Damas said:

CB3200 by design accepts smaller needle sizes, 794 is available down to 110-120 range but not in LR point

The best one to answer the conversion to needle system 328 needles and possible supply of 794 LR needles in the smaller sizes would be @CowboyBob. You should drop him a note.

kgg

Edited November 4, 2024 by kgg

[Damas]

Thank you ! I also found this post which suggests the opposite conversion with some interesting hints from @Wizcrafts :

 

[GerryR]

5 hours ago, kgg said:

......

Why not save all the fooling around with converting to a different needle system and convert to using a larger thread size, V138?

The cost of a 10 pack from the thread exchange for 794 size 160 LR point is $12.99 (~13 cents each).

The cost of a 10 pack from the thread exchange for 328 size 140 LR point is $11.29 (~11.3 cents each).

For me the less then the two cent saving would not be worth the associated conversion headache.

kgg

 

Small math error??

10 pack @ $12.99=$1.30

10 pack @ $11.29=$1.13

[kgg]

1 hour ago, GerryR said:

Small math error??

I'll blame that on having a seniors moment.

kgg

[GerryR]

15 hours ago, kgg said:

I'll blame that on having a seniors moment.

kgg

I completely understand!!

[kgg]

21 minutes ago, GerryR said:

I completely understand!!

Ain't getting old wonderful grand.

kgg

[Constabulary]

before you buy many different 328 needles I´d test one set first to see how thick you really can sew with the 328 needle and see if the needle holder does not hit the presser foot at max. material thickness.

[Damas]

I sure will, hopefully I already have a bunch of them, using 328 system on both 45k and 132k

[Damas]

I did the conversion this morning. I had to lower the needle bar of 6mm so from 23,5mm clearance to 17,5mm (from base of needle bar to top of feed dog)

Prior to this, I set the stitch length to 0 and position the machine to BDC as recommended by @Wizcrafts

It's the only change I made

I did tests using three layers of veg tan leather, total thickness being 12mm. It's not the max cb3200 can take (specs say 15mm) but it's my usual max

I used terko satin thread (Coats), tkt 025-tex 105 on the top and bottom

I tried 120, 140 and 180 sizes and it was perfect !

I'll give it a try in real working conditions for the next few weeks and report here

Edited November 7, 2024 by Northmount
fixed typo DBC to BDC