Bobbins for EI-120 Lamination

[rplate]

Hi folks!

I am facing a dilemma. I have bought M6 grade EI-120 lamination mostly for winding power transfomers and chokes. Now I have to choose bobbins, but unfortunately seller packing only one size per shipment.

I added a size for all available bobbins, of course for power transformers the bigger bobbin the better, but for chokes the bigger size probably will be overkill.

What size do you think will be optimal for EI-120 lamination?

 

[LinuksGuru]

You don't need to buy bobbins, you cut them from 2mm paxolin, presspan, FR2, or FR4 with CNC router or even sheet metal scissors. Look at instruction attached. Its in Russian but the basic idea is clear, its self-locking design.

 

[rplate]

Thanks! That's an idea! What is the original book? Is it something about practical transformer winding?

 

[LinuksGuru]

It is an old Russian book about basic transformer design and cosntruction. Old books available as free download from varius archive sites.

 

[Tubekwk]

Hi rplate

In the past I have successfully cut a piece out of the middle of a bobbin the reduce the stack size and taped over the join with some extra insulation at the ends, the cut needs to be very accurate. I guess you could also increase the stack size by using two bobbins to make one.
Ken K

 

[Tubekwk]

This book may help.

Coil Design and Construction Manual
By B. B. Babani
ISBN 0 85934 050 3

 

[rplate]

This book may help.

Coil Design and Construction Manual
By B. B. Babani
ISBN 0 85934 050 3

Thanks for the reference! Looks very interesting.