PI Mono Coil Cable question

[green]

Someone needs to start a thread to specifically to talk about coil types wire types and their relationships to SRf. Everyone could record data there and we would have one specific place to look for info on design potential of the different coil configurations and their application for use on specific target Tc catagories.\
Hint Hint.
I cant think of a better person Green since you have been working with this extensiveley .
That and you have a wonderful way of presenting data.
Just thinking Planting seeds.
Best Regards

I agree it would be nice to have a thread on coils. Lots of information in other threads. Some very long on graphite shielding and other topics. Wondering how to get a new thread to have needed information and still not be to long. Thinking test procedures for measuring desired coil information. Defining what coil information is wanted. Some build procedures. Ohers? Hopefully get them defined before starting the new thread. Any other thoughts?

[godigit1]

Hi Green,
You pretty much nailed what I was thinking but maybe a ongoing input of new coil data from different designs as well as Some of the pro coils could be evaluated.
It would be a great place to decide on a design or introduce a new disign for evaluation before starting and or deciding if a pro coil might just be worth the investment or not.
Thanks for thinking about this you allready have a good collection of coil data but getting it all in one place and adding to it in a defined manner as you say would be perfect.
So to keep it short maybe a sticky with desird testing perimiters and procedures and a ongoing thread to compare results, I guess we allready have that but maybe a place to gather the test data and discuss how to design for a purpose.
Thanks again

[Matt_Rowe]

Hiya Yatahaze,,,,I have tested my coils in shallow salt water, and No, water does not get inside. The coil cable and coil wire is one continuous cable. I use 16 stranded normal hook-up wire that is 0.5mm in diameter. The wire is rated at 600v and PTFE Coated. By being one cable the wire has no solder joints for the coil to see and the wire has less capacitance which helps the speed of the coil. When I have finished building my coil I wrap the coil in 2 layers of paper medical tape. Then I wrap the coil in cotton fabric that is 3/4 of an wide. I make a centre piece for the inside of the coil (for the ears to sit on) , out of 6mm plywood and drill tiny holes around the edge. I use waxed cotton thread (the type for sewing Tents, camping equipment etc,,,) to sew the piece to the coil. The waxed thread is waterproof and does not break easily so a lot of tension can be applied. I then put a coat of fibrglass resin on to the coil. When it's dry I apply another coat. I build up the layers gradually giving each layer time to cure. When I have time I will make a PDF document , with photo's, on how I do this. Hope this helps. Regards,,,Marty

did you ever make a pdf document yet, if so how can i download it

[Matt_Rowe]

Have a read of this paper. 'Stranded wire with uninsulated strands as a low cost alternative to Litz wire' by Xu Tang and Charles R. Sullivan. I downloaded a free 7 page copy some years ago but couldn't find a site today, although there are plenty of them that require membership to do so. Very relevant to PI coil and cable design and my personal conclusion was that there is no benefit to using Litz. Tin plated stranded wire does have benefit over solid, in that the higher resistance plating does break up the cross sectional eddy currents in coil wire. The paper explains all.

Eric.

Paper in pdf https://engineering.dartmouth.edu/in...%20useful%20to

[Matt_Rowe]

Hiya Yatahaze,,,,I have tested my coils in shallow salt water, and No, water does not get inside. The coil cable and coil wire is one continuous cable. I use 16 stranded normal hook-up wire that is 0.5mm in diameter. The wire is rated at 600v and PTFE Coated. By being one cable the wire has no solder joints for the coil to see and the wire has less capacitance which helps the speed of the coil. When I have finished building my coil I wrap the coil in 2 layers of paper medical tape. Then I wrap the coil in cotton fabric that is 3/4 of an wide. I make a centre piece for the inside of the coil (for the ears to sit on) , out of 6mm plywood and drill tiny holes around the edge. I use waxed cotton thread (the type for sewing Tents, camping equipment etc,,,) to sew the piece to the coil. The waxed thread is waterproof and does not break easily so a lot of tension can be applied. I then put a coat of fibrglass resin on to the coil. When it's dry I apply another coat. I build up the layers gradually giving each layer time to cure. When I have time I will make a PDF document , with photo's, on how I do this. Hope this helps. Regards,,,Marty

arty, did you ever do a pdf or something with your coil build, i have a minipulse kit coming from andy for my first pi build, beach model. thanks
M

[MartyJ1963]

Hiya Matt,,,Just seen the post. No, I never got around to making the pdf on 3dss coil build,,,It's still on my 'to do' list but just haven't had time with work etc,,,If you look up the 'Chance PI' Build thread (https://www.geotech1.com/forums/show...hance+pi+build) you'll find loads of info there (Baum7154) that's where I learnt to build mine,,,loads of good info,,,I don't use any other coil now only 3dss. Regards, Marty

[Matt_Rowe]

Thanks marty i will go read the thread and look for his posts,