Hello Guest it is November 12, 2019, 08:45:53 PM

Author Topic: Mach 3 Sewing Machine  (Read 24747 times)

0 Members and 1 Guest are viewing this topic.

Re: Mach 3 Sewing Machine
« Reply #20 on: December 30, 2015, 04:05:36 PM »
HI about a year ago I wanted to know how to computerize a quilting machine using Mach 3, I hadn't heard anything from sometime, so I jumped in to it.
I got a 18 inch quitter and stated building the hardware using belt drives, I found a good cam soft ware that outputted G-code from quilt libraries “quiltcam" and then wrote a visual basic program to add all the auto lock stitch, start and stops. I also added  some pokey and relay to interface with the stitch regulator on the machine and it new beautifully.
Did a bunch of quilts and found that I had to move on so I have now sold the machine….. It was a great project and fun for a while, but I still like the 4 axis mile and 3d printer to keep me busy.
Going to build a 48x 48 inch router this spring….. Thanks for just giving my project a thought.

Offline Tweakie.CNC

*
  • *
  •  7,984 7,984
  • Super Kitty
    • View Profile
    • Tweakie.CNC
Re: Mach 3 Sewing Machine
« Reply #21 on: December 31, 2015, 02:48:52 AM »
Hi Jonjell,

I am sorry you did not receive any interest in your 2013 posting  :'(  but it sounds like you have succeeded without any assistance from others here   :)

I think many of us have tried using Mach3 for quilting and embroidery but, at one stage or another, have all come up against the 5 stitches per second barrier (4 stitches per second in my case).

Tweakie.
Success consists of going from failure to failure without loss of enthusiasm.  Winston Churchill.
Re: Mach 3 Sewing Machine
« Reply #22 on: January 07, 2016, 02:18:02 PM »
If you use the stitch regulator that is used in most machine for manual quilting it is very easy, the stitch regulator detects that movement and speed of travel. So all I had to do is modify the g-code to turn on the stitch regulator and provide the path. It didn’t make any different how fast or slow I moved I had evenly spaced stitches
http://www.jonjell.com/Quilting/machinerunningmovie.html

I just needed the bedroom back ( well the wife wanted it back)
jonjell
Re: Mach 3 Sewing Machine
« Reply #23 on: August 09, 2017, 07:54:44 AM »
Informative thread.
Re: Mach 3 Sewing Machine
« Reply #24 on: August 09, 2017, 09:03:55 AM »
And I am still around

A conventional "plain" sewing machine controls the stitch length by the movement of the "Feed dog" that pulls the material from underneath in short strokes. Best you study an actual machine to see how it works the length of stroke can be adjusted by a knob or lever in the sewing head. A few "walking foot' or "needle feed" machines also feed from the top but that is another story.

A typical plain sewing machine operates at around 5000 rpm (equaling 5000 stitches per minute),  however quilting is thicker than say shirt fabric and it is normal to reduce the speed to between 3500 and 4500 RPM. You reach a point where thread breakages become an issue, there is too much friction and the needle can become so hot it will melt the thread.    

However a frame quilting machine head mechanically or CNC driven does not have mechanical feed dog. To control the stitch length you need to match the feeding speed to the stitching speed using a ratio that that gives the right stitch length.

These days most quilting machine designs use a moving head in an XY frame, the fabric in its frame stays still, mechanically considerably more complex, the benefit being a greatly reduced machine footprint.

The machine will be heavy with a large moving mass even for a small design, This means that unlike a manually driven machine where the material is stationary when the needle penetrates the fabric the machine will be moving and so will the needle, this can be alleviated a little by a the foot on the machine that holds the fabric down the "Presser foot" but there will be some movement. in spite of the movement the system will work as long as the stitch to feed ratio is not too big. Typically the stitch length at 3500RPM can be around 3mm. Longer stitches will require slowing the machine down.

For any given material, thread and machine there will be a sweet spot, Its not unlike metal cutting in that respect.

On The Mach 3 side the objective will be to maintain a constant feed / stitching speed ratio. at any feed rate, if this is not done the stitch length will vary.

I cannot imagine Mach could handle moves on a stitch by stitch basis except at slow stitching speeds? However it would be a good feature for things like "Back tacking" at the start and end of a line of sewing. Some sewing heads can also trim the threads off at the start and end of a line of stitching that would have a subroutine (It has to back up the line it just did)

Lastly sewing machines are not perfect there are too many variables thread will break. A means of reversing the program back to where the break was and a little past it will be required.

It's been a while since I thought on this I wonder if Mach4 is better equipped to handle CNC sewing?

Regards
john McNamara
« Last Edit: August 09, 2017, 09:08:49 AM by John Mac »

Offline Tweakie.CNC

*
  • *
  •  7,984 7,984
  • Super Kitty
    • View Profile
    • Tweakie.CNC
Re: Mach 3 Sewing Machine
« Reply #25 on: August 09, 2017, 10:04:38 AM »
Quote
It's been a while since I thought on this I wonder if Mach4 is better equipped to handle CNC sewing?

Hi John,

I think there is perhaps only one way to tell  ;)

Tweakie.
Success consists of going from failure to failure without loss of enthusiasm.  Winston Churchill.
Re: Mach 3 Sewing Machine
« Reply #26 on: August 09, 2017, 08:27:53 PM »
I think the way to do this is to build a square truss. Use  4 - 40mm square Bosch, or my preference Palleti rails. Take 25mm round tubing and flatten about 25mm long with an 8mm hole for a bolt into the slot of the 40mm rails. Then zigzag bend it for the diagonals of the truss.  When you assemble it you simply adjust a pair of rails for exact spacing and straightness. Make two straight pairs, then assemble into a square. Some corner to corner diagonals inside the truss make it torsionally stiff. Very light, very stiff, very straight.
Re: Mach 3 Sewing Machine
« Reply #27 on: August 09, 2017, 08:33:29 PM »
For the control side I would divide and conquer. Use Mach 3 for the pattern motion in X and Y. Use an Automation Direct BRX plc to control the stitching motor synchronization. High speed inputs from two quad encoders on the X and Y axis can be summed to give the PLC the linear speed. Then the PLC can use the high speed outputs to drive the two motors in synch with the linear motion speed.
Re: Mach 3 Sewing Machine
« Reply #28 on: August 19, 2017, 05:21:33 AM »
Great thread
« Last Edit: August 19, 2017, 05:27:23 AM by wilsonroy »
Re: Mach 3 Sewing Machine
« Reply #29 on: August 19, 2017, 05:22:35 AM »
« Last Edit: August 19, 2017, 05:27:39 AM by wilsonroy »