Any ideas on how to wind this PI coil ?

[6666]

I have been pondering the construction of this PI coil for some time, does anybody have any ideas on how to wind it to get the slight offset , I have been considering winding between two flat plates with a spacer slightly thinner than the width of two wires, and starting with a single wind of string to get the offset, any bright ideas ?

[chemelec]

First you would need to determine the Inner Diameter.

It would be easier to wind it reversed, going from the Outside to the Inside.
Using Crazy Glue to hold it.

I think the End result would be the same.

[6666]

Thanks Gary, I have worked out the approx inner Dia, I had not thought of winding in reverse , I will have to try and picture it in my mind for a while to work out how to do that mechanically.

[Tibuck19]

I have been pondering the construction of this PI coil for some time, does anybody have any ideas on how to wind it to get the slight offset , I have been considering winding between two flat plates with a spacer slightly thinner than the width of two wires, and starting with a single wind of string to get the offset, any bright ideas ?

Why the graphite ? with 24awg wire, shielding is not be needed unless your hunting where there is lots of wifi routers and lots of electrical interference, but if your like myself, hunting in urban area's with a Surf PI, you end up digging more nails then treasure's .

[6666]

The graphite is for sea water.

[qute1]

Perhaps use a centre disc former with one beveled edge to start the coil off and dabs of sg as you go to hold in place should not be too painful as only 20 turns please keep us updated with your progress and any tips you develop!

[6666]

I like the bevelled edge thanks

[Tibuck19]

IC I didn't think with bigger gauge wire it would be effected that much by salt water. In that case if I was to make it , I would probably be using my 3dprinter, I would make a coil wrap and make the coil housing in two half's leaving a 0.4 mm wall ,5 to 10 mm over hang on beyond one of the two half, I would spray the graphic in to both, then insert the coil, and acetone both half's together and pour the Epoxy resin throw the a fill hole.

[6666]

then insert the coil

Any thoughts on how you would wind the coil wrap ?

[kt315]

this coil is not fast tipo and no sense to tell more.

[qute1]

Give us your design for a best fast coil for surfpi then kt315 (fast tipo) do tell us more oh great guru....

[kt315]

give give give us. oh great guru! give. nothing of own mind control.

i say again - your mistake filling the coil by epoxy.
look on table at right https://en.wikipedia.org/wiki/Relative_permittivity
you never get fast coil with epoxy.
your physics school level is very poor. thats big trouble.

[kt315]

I AGAIN GIVE FULL INSTRUCTION HOW TO DO FAST COIL RIGHT

[Tibuck19]

Any thoughts on how you would wind the coil wrap ?

This is going to drive KT nuts loll , but I first print circular U channel which act's like a bobbin or spool ( much like how Garret makes their VLF coil spools), I did I bit of testing on making my PI coils this way and I see no real depth lost with an open air coil or a U channel spool made from ABS plastic, I'm sure what KT is trying to say is right, BUT shesh how else is one, to make a coil Especially for a Surf PI , it is not the most advance metal detect lol i'm no expect by any means, however i'm rather sure the circuit would never be fast enough for the kind of coils KT has in mind anyways! Perhaps KT can post photo's of finish coil that he makes ?

[qute1]

Thanks kt315 and tibuck love the banter and yes some of us have only been making coils for a couple of years and only wish to see how the masters do it!
Took the liberty of a quick translate for all us englishish speakers hope thats ok KT315.
PI_instr.ru.en.pdf