disappointment

[porkluvr]

I was planning on using 1/4" dowels but I have not drilled the 1/4" holes in my platform. Good thing.

After reading about your problem, SB, what I may do instead is to use either L or D shaped hooks covered with a piece of Teflon tubing. I'll raise the windings off the platform surface and hope that whatever varnish or glue I use won't stick to Teflon.

"D" hooks would act as a channel. I have yards of regular shrink tubing but I'll need to purchase some Teflon.

[Tinkerer]

I often loose count while winding a coil.

Can anybody recommend a cheap, simple turn counter?

Tinkerer

[CrotalusAtrox]

You can get PTFE or FEP or UHMW PE tapes that won't stick to epoxy. Get one with an acrylic adhesive. The Teflon types are expensive, UHMW PE slightly less.

McMaster-Carr has a variety in their catalog:

http://www.mcmaster.com/#high-performance-tape/=7sxeli

PJ

[simonbaker]

I was planning on using 1/4" dowels but I have not drilled the 1/4" holes in my platform. Good thing.

After reading about your problem, SB, what I may do instead is to use either L or D shaped hooks covered with a piece of Teflon tubing. I'll raise the windings off the platform surface and hope that whatever varnish or glue I use won't stick to Teflon.

"D" hooks would act as a channel. I have yards of regular shrink tubing but I'll need to purchase some Teflon.

I'd like to see what that looks like.

But dfbowers has no problems with his winder, so maybe check with him first, don't get turned off by my results. Maybe varnish works better, or he was more patient and careful applying non-stick coating.

Also, I found 1/4" pegs can bend inward, although using a top platter should help that a lot. I use 3/8" pegs.

-SB

[mikebg]

I often loose count while winding a coil.

Can anybody recommend a cheap, simple turn counter?

Tinkerer

Tinkerer,
I converted a mechanical kilometer counter designed for cycling. Eliminate its gears. In order not to rotate his body, hooked to body a small weight that hangs like a pendulum. If you find such device and disassemble it, you'll think of how to convert for turn counter.
When my colleagues asked to repeat my ugly but simple and cheap turn counter, it turned out that the bicycle shops no longer offer mechanical counters, but electronic devices called "bicycle computer". They are inexpensive, easy to reset and can be designed very elegant coil winder because use magnetic sensor. However, the models are not able to show directly the wheel turns, but show the result multiplied by the circumference of the wheel. My advice is you to visit several bike stores and getting to know the capabilities of the proposed devices. You may come across a model that can be integrated in coil winder.

[Tilladude]

Simon,

You could try baking paper, the stuff they sell in kitchen ware shops and such. It doesn't allow the oils and sugars to get through and stick to the metal sheet.

I would wax the boards first then staple the paper down around the edges and go about winding the coil as normal with whatever "thane" you want to use. Then when you seperate the form coil should come out covered on both the paper, trim the extra paper ( maybe leave enough to finish wrapping the coil) and apply the shieding material.

Just some dribblings from my aging grey cells.

Take care,
Dennis

[Qiaozhi]

Or you could try this stuff ->
http://www.amazon.co.uk/BakeoGlide-2.../dp/B00175QHTU

[Tinkerer]

Tinkerer,
I converted a mechanical kilometer counter designed for cycling. Eliminate its gears. In order not to rotate his body, hooked to body a small weight that hangs like a pendulum. If you find such device and disassemble it, you'll think of how to convert for turn counter.
When my colleagues asked to repeat my ugly but simple and cheap turn counter, it turned out that the bicycle shops no longer offer mechanical counters, but electronic devices called "bicycle computer". They are inexpensive, easy to reset and can be designed very elegant coil winder because use magnetic sensor. However, the models are not able to show directly the wheel turns, but show the result multiplied by the circumference of the wheel. My advice is you to visit several bike stores and getting to know the capabilities of the proposed devices. You may come across a model that can be integrated in coil winder.

Thanks for the feedback.
I will look up the local bicycle shops for parts.

Tinkerer

[simonbaker]

Simon,

You could try baking paper, the stuff they sell in kitchen ware shops and such. It doesn't allow the oils and sugars to get through and stick to the metal sheet.

I would wax the boards first then staple the paper down around the edges and go about winding the coil as normal with whatever "thane" you want to use. Then when you seperate the form coil should come out covered on both the paper, trim the extra paper ( maybe leave enough to finish wrapping the coil) and apply the shieding material.

Just some dribblings from my aging grey cells.

Take care,
Dennis

Yes, I know what you mean. I stole some "parchment paper" from my wife's kitchen supplies (again) which I think is same thing. I'm using it for base while making a latex mold of dfbowers coil shell. In that case, it doesn't stick. But you are saying, let it stick, so what, just trim it away. Yes, I see the idea; might do the trick.

What if I put down aluminum foil, let it stick, and then used it to wrap shield -- but I need piece on top also. Problem is wire may get under it if not really fixed down perfectly -- wire rubs along surface.

I feel need something really easy, no fuss.


Thanks for the dribblings.

-SB

[Tilladude]

Simon,

Dribble, dribble, dribble, I think I might have to see a Doc. about this.

Yup parchment paper is what I meant and yes you would need top & bottom pieces. I like the idea of using foil, you would jhave to cover and roll over the edges of the boards and maybe use heavy duty foil to keep the wire from tearing it. If you are doing a layered coil you probably wouldn't be going very fast anyway and tearing shouldn't be a problem.

Take care out there,
Dennis

[Mullihaka]

Nabiul proposed using polyethylene cutting board for coil former. I did.

Using router, I cut 4mm wide and 5mm deep slot around the board. That needs steady hands as the board is only 6mm thick.

I spread 2-component epoxy at the bottom of the slot around the former as proposed somewhere else in the forum. I did it at 10 C, so I hade some extra minutes time before it started to cure.

I had cut the former in 4 pieces like in the picture. When the epoxy had cured, it was quite easy to slid the square part inwards out of the former, and then the rest 3. The big pieces needed some prying with a small screw driver. However, I got the coil out without breaking it or the former.

The former should not have the back of the D straight but a bit curved. The wires did not sink deep in the slot as they did on the belly side of the D. That left the straight part a bit thicker and the inductance lower than calculated.

I think that only one D should be epoxied hard. Having the other D tied with dental floss, taped, shielded and taped leaves it a bit flexible, which is needed to make slight adjustments in nulling. That way most of the circumference can be glued and a small section at the middle of the back of the D left without. Having both Ds rock hard looks difficult to null, as it's more difficult to handle whole D than just adjust a 5cm section of overlapping back of the D.

[Jerry]

I do not understand your disappointment. That coil looks pretty nice to me. Also you took another approach and proved that it does work. I think that is success!

I agree with you on the straight sided D coil. I found the same thing and will try a slight curve on my next one.

Thanks for posting your work.

Jerry

Sorry, I wrote this before I read the entire thread. took things out of context Admin can delete if you want.

[satdaveuk]

Its all trial and error me old mate, I made loads of coils before i got it right, its nice to see others trying different angles, thats good for all of us.

[nakky]

I did it this way.
Grt Nakky

[WM6]

Noble work nakky!