What would your ultimate needle positioner/synchroniser do.

[toxo]

@beefyI haven't understood half of this thread so I just want to throw in my two penn'orth. Firstly the Chinese usually copy everything so I doubt that your servo won't do what all the other servos do. I still haven't got to the bottom of tuning my N/P because my machine came with a speed reducer. My China contact has asked for a video which I've sent and am awaiting a reply but Chinese holidays can be quite long. The N/P on my new machine has a N/P that I'm not familiar with so Im wondering if yours is the same. Here's a pic of what I'm gonna call "the old N/P". This is completely different from "the new one". The old one was a breeze to adjust (no speed reducer but a very big handwheel instead) As you can see, the old one can be adjusted simply by turning the relevant disc which breaks the circuit by way of a cutout. I'm thinking that you might not have seen this type. Forgive me if I'm teaching granny how to suck eggs.

Edited 6 hours ago by toxo

[beefy]

Hi Toxo,

Thanks for posting that picture. I might actually use the design method of that one to make my own but with magnetic hall sensors instead. Only problem I can foresee is a hall sensor on on disk may pick up the magnet field from a magnet on a neighboring disk.

No I've never seen your old type, as I am very new to this industrial sewing machine stuff. I've only seen the ones all over Ebay, Aliexpress, etc. My guess is the sensors on your old one are infra red receiver/transmitter types.
What I like about that physical design is it's easy to build (I've got a lathe). Downside is it's a bit more bulky as more position disks are added.

Did dust ever cause the optical sensors to work correctly ?

Yep, seems many Chinese sellers think the need for instructions is just plain silly. The instructions that came with mine are just completely wrong, and probably based on some other controller. And when you hassle them enough to give you some instructions it's still terrible and not complete. That's what has made me give up on them and play with this idea instead.

Edited 4 hours ago by beefy

[beefy]

3 hours ago, AlZilla said:

Yes. The thicker threads we use for leather create a lot of unsightly bulk when you start forward, back up and come forward again.  And the hole created by the needle isn't really big enough to have 3 stitches run thru. I use V138 and up. 

I start, needle up, where the 3rd hole would be and drop the needle 3 times, backwards. That gives me 2 complete stitches, with my needle all the way down and at the beginning of my intended stitch line. Now I can stitch the "right way"  (forward) and I get 2 locked stitches when I hit the 3rd hole again. 

With domestic sizes of thread and needles on fabric it's not so obvious.

On my machines without reverse, I do the same thing by turning the material around.

Simple to do, but apparently takes a lot of words to explain... 😃

Thanks for explaining that AIZilla.

Had a little laugh with what you said, "Simple to do, but apparently takes a lot of words to explain..."
That's just like the programming of my needle positioner. Seems such a simple task yet the coding takes a lot of time and focus, and keeps getting longer.

[dikman]

12 hours ago, beefy said:

To be honest this is more a labour of interest rather than a huge necessity. I get very engrossed in the design and programming and the hours tick away quite quickly.
And when the design is completed (and works LOL) I enjoy it every time I use it. 

I can understand that! I often do/make things because "it seemed like a good idea at the time" or it was just a challenge to do it. I suspect it will end up being more complex than you think but best of luck.

[toxo]

3 hours ago, beefy said:

 

Did dust ever cause the optical sensors to work correctly ?

No! It usually has a cover over it and looks the same as any other.