Small Coil Winder Project

[DaftFader]

F Looks nice and simple

Nema 17 - maybe the answer. There are closed loop versions around for about £30 , so if the torque is sufficient , that would do nicely.

 

[oran.outan]

Torque stepper are in my experience more relative to the driver than the stepper him self... like the cheap and commonly used A4988 has 1.5A but not so much power so definitely go to something stronger with like 2.5A...

With pick up, i laser cut the ‘frame’ out of vulcanized fiber, wire are 42/43 Awg...
I have no experience with transformer, where/how do you find/made the frame !? What are Awg used?! I imagine ratio are related to turns number...
Don’t see so much info around...
Thanks

 

[DaftFader]

Here's a video of it running with a low-cost stepper and driver . The NEMA23 motor is from stepperonline and cost about ~£20 and the TB6560 driver from ebay was £11 - both could be found for less.

The closed loop stepper was good for a couple of thousand RPM, this combination seems to peak at around 1100 RPM (torque drops rapidly with revs so upper practical limit will be far less)

The feeder seems to work OK , but I've got to either find a faster opto-isolator for my homebrew driver board, or maybe find a pre-made board [edit] I could use another TB6560 board but the minimum current is a a bit too high at 300mA (<200mA would be better) .

 

[Whoops]

It looks very nice.
I really want to do a similar project as I'm in desperate need for an automated machine.

This is what I'm using today, totally manual,
takes a long time, my back hurts, my hands hurt, tough business:

 

[Tubetec]

I started out with a similar hand cranked winder Nz-4 or 5 I think . clockwork counter .
What I find most awkward is right hand wind and left hand as wire guide ,
curious that it seems set up for 'lefties' . Before I got my cnc I made a basic coil winder from a cordless drill motor /chuck/ speed control and mechanical counter , winding width limits are set by stops on a metal bar below the main shaft , trigger control from the drill provides varispeed in the left hand , wire is guided with the right hand .
Works ok for small inductors or mains transformer than dont require much precision .

 

[Whoops]

What I find most awkward is right hand wind and left hand as wire guide ,
curious that it seems set up for 'lefties' .

Hi mate, I'm right handed and I can't guide with my right hand.
I can only guide with my left hand and wind with the right so it's perfect for me. So I can't agree it's setup for lefties, I guess it depends on the person.

Probably it's similar to the position of the foot in skating or surfing, half the people that have a stronger/dominant right leg put the left foot front on the board and the other half of the people prefer to have the right foot in the front position. It's seems it's a personal thing and independent on which is the dominant leg for most other things.

 

[DaftFader]

Whoops, this is exactly the type of job I designed the winder to do - one-off / low quantity workbench winding.

ATM I'm finding hard to judge how much effort I should put into reducing the skill required to build the winder . I really don't want to have to produce a kit (It'd be less trouble to make the complete thing) , but it's clear that most people need simple to assemble, easy to buy parts.

What skills and machinery does the average DIYer here have available?
I'd expect wiring skills (soldering crimping cables etc.) .
Fabrication? drilling, filing, cutting, shaping metal parts - probably.
Milling/Turning ? - some might.
3D printing ? FDM maybe - MSLA less likely
Micro-Electronics? programming PICs etc. - unlikely
Programming (Python/PIC assembler)? - I don't even do that well
PCB layout ? - did I ever tell you how much I hate laying out circuit boards? ;-)

 

[volker]

What is the maximum diameter you estimate could be wound?

If you need a hand with a pcb layout let me know, happy to help.

 

[DaftFader]

>>If you need a hand with a pcb layout let me know, happy to help.
Hi Volker, I may have a job for you...

>>What is the maximum diameter you estimate could be wound?
It depend on motor torque (which is speed dependant ) and wire tension/diameter - Sean's mini winder (CNC Design - Guitar Pickup CNC Mini Coil Winder | CNC Design Limited) is able to handle guitar picks up to about 70mm across with a closed loop NEMA17 motor . My design should be able to wind pickups, and other bobbins of similar diameter, OK . The physical limit of the 'box' is about 100mm.

 

[DaftFader]

Here's one board that needs a layout:
This is the Pulse-train PIC board. It takes a serial input from either a raspberry Pi or a PC serial port and generates the stepper motor pulse trains. A third PIC counts the revs.

It has a SMPSU DC-DC converter to power 5V to the RPi etc.

Connector (clockwise from top) :
40pin RPi GPIO hat plug/socket
4pin external serial port option
Wind motor (Xaxis)
Feeder motor (Yaxis)
Counter input
I2C break out (for local display )
24vdc input terminals

 

[12afael]

do you have a schematic for it? I suggest to use Easyeda that way many people can work on the project easily. I think I can put some time on it.

 

[DaftFader]

I'm working on them Volker has very kindly volunteered to layout the Pi hat board
I'm still searching for a suitable small & cheap stepper driver board for the feeder, if anyone knows of one. (ideally it should have opto-isolated direction, step and enable inputs and a single 24vdc power requirement and a <=200mA drive )
There is a simple inter-connect board that connects two hall effect sensors (small transistor sized devices) to the counter's 6way input (see photo) . I've used a short length of IDC ribbon but maybe a flex PCB would be better .

 

[DaftFader]

suitable leads and headers :

https://www.ebay.co.uk/itm/18278577...rentrq:e4540a1517b0a9d963695f41fff97a88|iid:1

 

[DaftFader]

Apologies to those waiting for the schematics : I'm buggered if I can get my Win7 home machine (which is running the pcb app) to print or talk to my network ????

 

[DaftFader]

gave up with the network and used a usb stick...

Apologies for the schematic , not as polished as I would like , but if I spent another minute using that ****ing abomination of a program - I'll go mad (or even madderer)

So here's a pdf of the PTPIC hat. the PICs should use 8pin DIL footprints so they can be socketed , the level shifter module on the I2C is optional (12pin 0.4" DIL), it's not required for the small OLED display that I originally used , but would be useful if some other 5v display or I2c device was required.

ATM each of the PICs has to be programmed with an axis identifier character (even though the code is identical for both axes) because I'm using all the pins. Anyone have a good way to encode the socket so the PIC can know which axis it is controlling ? (i.e. add a resister between the step/dir pins that can be read by the PIC during boot somehow).

The DC-DC converter is one of these:DC-DC 3A Buck Converter Diy Kit Electronic PCB Board Module LM2596 Power SuO7S2 193571255242 | eBay

 

[DaftFader]

I won't post the pic assembler here, but here are the binaries for axes and counter . The Pulse Train PIC was to be a universal stepper pulse generator when it got morphed into a one for coil winding so might have some other uses.

**********************************************************************
;                                                                     *
;    Filename: PTPIC.asm                                              *
;    Date:     14/09/2019                                      *
;    File Version:      1.61                                           *
;                                                                     *
;    Author:             W.K.Todd                                     *
;    Company:            Todd Electronics                             *
;                                                                     *
;                                                                     *
;**********************************************************************
;                                                                    *
;    Files Required: P16F1572.INC                                     *
;    Pulse Train generator for stepper driving              *                                                  *
;**********************************************************************
;   Serial control commands (@19200 baud)                         *
;   All commands are 10 ascii chars                      *
;    (Axis, Command, and 8 hex) terminated with colon (:)          *
;**********************************************************************
;x = axis (X,Y, Z, or E)
;   xA0000tttt        set Acceleration/deceleration time
;            tttt - time in centiSeconds = 0.01S (hex16)
;   xB00000000        Brake - decelerate to stop
;   xFdc0iffff        set frequency
;            ffff = frequency in Hz (hex16) (maximum is about 25kHz with 32Mhz PIC)
;            
;            d = direction (0 or 1)
;            c = cycle (0 or 1)
;            i = immediate (0 or 1)        
;   xDxxxxxxxx:        set number of steps (Distance) 32bits hex
;   xCxxxxxxxx:        set cycle steps (reverse direction at cycle)
;   xNhhhhhhhh        Nudge cycle left or right
;                   h = 32bit signed hex
;               <7fffffff = positive = left = dir 0
;                   >7fffffff = negative = right =dir 1
;   xOelnk0pms        Options
;            e - 0 or 1 motor enable
;            l - 0 or 1 limit enable
;            n - continue  cycle count and direction
;                   k - continue  steps
;            p = polarity 0 falling edge or 1 rising edge
;            m - Motor enable active 1= high 0=low
;            s - limit Sensor active 1=high 0=low
;   xP00000000:     Position - set ABS position
;                
;   xSel000000:        axis stop
;            e - 0 or 1 motor Enable
;            l - 0 or 1 check if at limit (returns xL: if at limit)
;   xGel000000:        axis start (go)
;            e - 0 or 1 motor Enable off when stopped
;            l - 0 or 1 Limit enable
;   xV00000000: version string
;************************************************************************
;   AS00000000:     All stop (no options are set)
;   AG00000000:        All go   (no options are set)
;************************************************************************
;Responces:
;   PTPIC vx.xx: (xV00000000:)
;   xShhhhhhhh: - axis has stopped
;                   hhhhhhhh= ABS position (32bit hex)
;   xNhhhhhhhh: - Cycle Position
;                   hhhhhhhh= position (32bit hex)
;   xG: - axis is running
;  xC: - Cycle has reversed
;   xL: - Limit hit (when enabled or checked)
;
;**********************************************************************
;e.g. quick setup acctm 2.5s cycle 0.5Hz Frq 1kHz
;X go @ 1000hz 10s acceleration >XA00000100:XC000003ff:XD0fffffff:XF000003e8:XG00000000:
;X decelerate to stop >XB00000000:
;Y go and oscillate > YA00000100:YC000003ff:YD0fffffff:YF010003e8:YG00000000:
;Y nudge left or right > YN000000ff: YNffffff00:

 

[DaftFader]

Git-Hub initial commit

https://github.com/WKTodd/Coil-Winder/tree/main

 

[Bo Deadly]

Wow. TK, asm and stepper motors. That's some old school fun.

 

[DaftFader]

>>>That's some old school fun.
Yep I went to several old schools

 

[DaftFader]

Updated github again :
Windersettings.py now includes motor enable options to suit cheap stepper board and serial port selection (including a simulate option if you want to try software without the hardware)

Winder.py is the main file so run this from command line if you have python installed
>>python3 Winder.py