[james_III]

Hi....

interesting thread for many years ,

Has anyone built an embroidery machine to do logos on baseball caps ?

Don´t know, but should be doable. It have to be specific machine just for baseball caps, because of somewhat round movement, can´t see why not. This really is interesting topic and still waiting some necessary parts to start the build.

[james_III]

Some progress, hope this image is approved size etc etc... Now this contraption needs plywood base and mounting biggest secondhand stepper I have.

[paul3112]

Hi. Is the X - Y plane a curved surface?? I am thinking the that if the surface of the cap is a curve then a rotary actin is requires

[Jmlaser]

I tried the Gcode converter (different versions picked up from here), but the generated code is not good.
It is valid and can be read by my CNC machine but there is lots of information missing.
When I compare an original dst file in Sophiesew with the file converted by gcode converter, the picture resolution is very bad.
Seems that most of the image information is optimized away.
Nice program, Khalid, but something seems to be wrong with optimizer.

Joachim

[Khalid]

Check your system settings . I think our Gcode generate taking "." as decimal point and yours system settings are set "," please see post 929 and 930..
http://www.gesphy.ch/images/stories/...ws_8_et_10.pdf

[james_III]

Slowly, actually I'm further than this. Belt would be better but difficult to get over here.

[renj]

Khalid

Great initiative and hats off for the progress. I also want to try one embroidery machine, i am looking for Arduino based and with servo motor.
For variable stitch to adjust the speed of servo, you said calculating the length of stitch from x and y coordinates, have you got the solution for it, is it possible.
I hope we can copy and paste the g code generated by your software into arduino.
what is the equation that LASRI was mentioning.
does the g code generated in your software have any information about the angle or distance between x y coordinates . so that it can be used for z speed control. just asking
thank you

[renj]

Thanks,
The project achieved its milestone for embroidery but the number of stitches per minute is too less. Our main goal should be to achieve commercial stitches/time.
Yesterday i was thinking on how to program the microcontroller that can get G&M code and transfer to hardware for their rapid function. I mean high speed stitching speed..
1- 1st line of attack would be to add a simple optocoupler and a special encoder disc that will measure when the needle going inside the hoop and coming out. I will use interrupt function in the microcontroller
2- SIMPLE CONDITION: You run the wheel motor to its maximum speed and just pause the X-Y at the location when the needle just start entering and until it comes out. This approach will be good for small length stitches but not work well for Jump Stitches (May be when jump stitch comes we stop the wheel and make sure the needle is up ).
3- COMPLEX PROGRAMMING: To get the variable stitch length we should control the Wheel motor using PWM . We will 1st calculate the length of stitch and then adjust PWM of wheel motor and slow/fast it so that almost accurate stitch length achieved. For this We may have various approach. As i am going to do programming of microcontroller from scratch so all of community feedback will help me great.
WE MUST COMPLETE THIS PROJECT AS EARLY AS POSSIBLE FOR FAST STITCHING.

khalid

The logic looks great.
thumbs up.
could you please also think of option for offsetting the design in the hoop, means towards the edges of the hoop, useful when doing continuous long designs
commercial mahcines have a photointerupter sensor on both x and y axis , i think to get both axis to home position before starting stitching.
Are you planning to calculate the distance between x1y1 and x2y2 coordinates mathematically and use that value to control the pwm of servo for variable stitch length?

thank you

[james_III]

Wow, I actually need to make some sort of hoop or loop or something. This contraption is sort of ready to do testing

[james_III]

It sort of does something :banana:

[Khalid]

James... Awesome man awesome.. do you have videos to share..

[jastinegaming]

what do u mean about paper patterns?

[james_III]

No video at this point, did dismantle nearly everything and currently rebuilding. Reason was too difficult to change or mount hoop. Now everything should be much more nicer and user friendly. Running sewing machine directly from G-code is not necessary fastest thing there is but it seems to work. From one 7000 stitch program I calculated speed was 100 stitches/minute. I ordered new power supply, seems like I don't get full power from sewing machine stepper, it is not even warm. I hope to speed up eventually when everything goes together.

Second idea would be change angle of attack. It is quite possibly to drive separate motor circuit using output and input from GRBL.

Something like:
M4 //request motor cycle
M0 //hold until resume is issued
M3 //setting move mode

Those are pins that already exist on GRBL platform.

[james_III]

Slow speed teaser

[Khalid]

James, nice work.. can we increase the speed more than this...

[james_III]

Yes we can increase speed, actually it did run 100 stitches/minute before. In the video it does probably 1/3 of this, I had to gear it down to get some torque and slow down, sewing machine had some timing issues. Near future plan is to gear it back up 1:1 and when my 24V PSU arrives I will double the voltage. Maybe then there is more speed available. Problem is there is nowhere documentation on my stepper motor, no voltage no torque. Driving on 12V it is not even warm and current limit is off. If I decide to buy new stepper motor with known characteristics, best bet would be closed loop one, so it will recover if thread comes tangled. This is work in progress.

[Khalid]

What electronics you are using/.. Are u using Mach3 as a control software?

[james_III]

Using arduino with GRBL controller shield. I think Mach3 is not compatible with USB interface. Best controller software I have found is Grbl Panel, free like many others on arduino platforms.
https://github.com/gnea/grbl/wiki Nema17 steppers are driven with DRV8825 and sewing machine TB6600.

[james_III]

Let there be more speed:



something around 150-180stich/min, huge leap forward after thinking less microstepping ---> more speed. Maybe stronger stepper can go little bit faster, but not much. Closed loop should get past 200 with ease, my max attempt was 190~ and it was way too sketchy, matter of time to loose sync.

[james_III]

Some more progress, changing sewing machine, stepper to back feed stepper type and different style rotating code, it seems 400+ stich/min is possible. Unfortunately this needs special presser foot, with normal embroidery foot, speed can be around 300 stitch/min. Still doing improvements.