Re: Winding coils on a CNC lathe

Tesla List wrote:
> Original Poster: timp-at-clarityconnect-dot-com
>         Hi all, I'm in the early design stage of my first
> coil and the machine shop that I work for just bought a
> CNC lathe (10 feet between centers and 18 1/2 inch swing).
>         If anyone has tried winding secondary or power
> transformer coils on a CNC I'd appreciate any advice.
> Winding the secondary shouldn't present any problems but
> winding a rectangular transformer coil is going to present
> some issues with feeding the wire.
> Thanks in advance,
> Tim

hi Tim..... 

I had the opportunity to wind a few coil sets for current limiters using
rather large I - E  core sets. The easiest way i found to do this on a
lathe set up  was to measure the core section on which the coil is going
to be placed and then make a wooden form that is about 1/8" larger on
both sides ( if you have a core of  3X4 make the wooden block 3 1/8 X 4
1/8 ) this allows for easier placement of the coil onto the core. After
cutting the block from wood wrap it in waxed paper ( about 2 turns )
make 2 end plates from wood ( about 5" larger than the core dimensions)
to contain the wire on the block. drill a hole in one plate next to the
block ( insert wire here to hold it in place ) start turning wire on to
block and use a soft rubber hammer or wooden part to tap the wire into
place be careful not to nick the insulation. Once you have the sufficent
amount of wire on the block, wrap the coil with tape, remove from lathe
, remove both end plates and support coil between 2 supports , tap out
the wooden block and place onto metal core. Once on the core slide some
wooden shims between the core and coil ( this tightens the coil to the
core ). You may want to consider insulating the core before putting the
coil onto the core. It took me about 45 minutes to do each core set with
this system.

Scot D