Complete information on working SM style device.

[CTG Labs]

One coil done 3 to go

35SWG 1.85km 774 Ohms3.23Henrys

Peter

Hi Peter,

Nice wind!  How did you manage this?  I built a coil winder with PIC micro and stepper motors, but I could not get something this good!


Regards,

Dave.

[Peterae]

Hi Dave
Thanks for the comments.

LOL i was going to build a coil winder just as you described, but thought i would try a manual wind first, it was not so hard really.
i wanted a 38mm hole in the middle and 19mm square cross section coil, because i am driving at 330v fast pulses, i needed as much wire as i could get on the coil to increase the resistance.

I bought some 38mm washers with 8mm hole in middle, i used enough washers side by side to give me 19mm, i then placed two old cd's each side and two mdf disks i cut the same size as the cd's for stiffening the cd walls i then used 2 large washers to hold all together with long 8mm bolt.
I put down a thin layer of insulation tape over the washers to wind onto.

I then placed the 8mm bolt into a speed variable battery drill and held in a vice,i fed the wire through a long small dia tube to hold and feed the wire into carefull layers, with a bit of concentration and practise i got very good results, every 20 layers or so i stopped winding and brushed a layer of Laquer on the wire, i continued this until all 1.85km were wound.

I then put two more coats of laquer on the outside of the coil, and when dry i carefully dismantled the mdf and cd's, this was tricky because the cd's were glued to the coil so i used some fresh laquer to redissolve at the cd interface and then with a gentle twist of the cd removed it.

Once both cd's were removed, i then painted both flat sides with about 4 layers of Laquer with good soakings and when dry, i then removed the washers from the center, and then painted laquer on the inside.

I used a fast drying Laquer 30 minuets drying time.

Hope that helps

the finished coil is over 0.5kg Gulp

Peter

[CTG Labs]

i continued this until all 1.85km were wound...

Ya, a lot of wire!

How long did the over all wind take?


Regards,

Dave.

[Peterae]

Heres a picture of the Tetra Frame, i used 1.5mm card covered in masking tape as the mold, then filled with resin.

Peter

[Peterae]

It takes about 30-40 minutes to wind it, and then a day or two of laquer painting on and off.
Even with the drill at full speed i was able to get good control over the layering, it almost finds it's own path across with a gentle help.

Peter