Coil Winder - Rev 2

[gemini86]

I'm getting ready to build my rig soon.

I have my totalizer hooked up with a reed relay and a magnet on the chuck to give me turns counting. only one direction, but I'll live with it for now. I'm wanting to wind some really fine wire, machine fashion for nice flat layers. CJ says it can be done without a travers guide, but no matter what I try, I cannot get a good layer without overlapping or just getting stuck in the corner. How far away does my wire guide/tensioner need to be from the bobbin? About a foot? More? The sections I'm winding are less than 1/4 wide.

 

[CJ]

move in close if you wind the small stuff,

you can find mechanical winders on evilbay for cheap, Veeder Root is the brand you want,

as soon as you hit the margin you need to really put a big lead on the guide to get the wire to swing back the other way,

for tension i just tape a piece of light foam around the wire and attach it to something,

 

[gemini86]

so are you leading the wire as it winds or just letting it lay naturally? I've tried even winding by hand, but there's no way that will work.

 

[CJ]

what size wire are you using?

anything over about #38 and you really need a stepper motor and a lead screw,

you can feel and see the wire snap over the previous turn as it rounds the 4 corners,

that would be the max turns per layer, there are many points in between max turns and a visible air gap, so it may look like the wire is right next to each other but there is a micrometer of air in between,

all the V72 chokes i have unwound have been hand wound, no perfect layers,

now days, you can buy machines that will wind #44 with max turns per layer, i think that is what Ollie is doing at Funkenwerk, they say turn to turn capacitance is so small that you do not need to worry about it, but with 21,000 turns you would think it would add up, so i put a little air in between each turn,

there are also 2 pieces of poly insl per chamber on the stock Tele chokes, i guess they are trying to cut down on capacitance, these are 1 turn pieces that5 occur about every 2500 turns,

 

[gemini86]

I'm using 42 since I got a deal on it and thought it would be easier to work with. I guess I'll just give this one a go random wind.

 

[CJ]

getting a little more automated on this winding machine,

use to have to manually switch directions of the wire traverse with a switch,

took some PNP transistors out of the junk box and built a one shot circuit,

then added some contacts to the traverse and wired in an octal relay,

here is the schematic and a pic of the sw. contacts,

used sheet metal that will bend in case of a malfunction,

saves the motor and lead screw,

took a movie, was going to link it to youtube but 89 meg is too much to watch a platform change directions, 

tried using 3 different mechanical switches mounted to the platform, but they always got stuck in the middle and the motor made weird noises so you need a no bounce sw for this,

using a threaded rod to allow adjustments for different bobbin sizes,

now i can make a cup of coffee while the machine is winding back and forth,

an opto-isolator is inside the Geckodrive, sinks about 16 ma at 5 volts in order to reverse the direction of the stepper motor,

you could use a single 5 volt supply with NPN transistors and just use an open collector to sink the current if you want,

a relay makes a nice clicking noise which tells you that your wire has changed directions, which lets you know that wire is not being wound on the spindle,

 

[12afael]

CJ, what are you using for the traverse mechanism? I thought it was a gecko device but it is just the driver isn't?

best regards
Rafael

 

[CJ]

here is the traverse mechanism, a small stepper motor with a belt drive to the lead screw,  on an aluminum frame, picked it up at a surplus shop, some type of CNC driven parts maker, it is kind of slow since the lead screw has many threads per inch, but that is good for small coils,