[beery]

Hi Travellingwave,
That sounds great.
Do make note of the number of turns per layer. This has to be the same for each layer (except the final one). This ensures that subsequent layers have a flat surface to rest on. There is a paxolin coil former which the windings sit on. Reuse that, though you may have to cover it in a layer of tape first as it may have split due to the rusty laminations.
I've had coil winder bobbin adapters made (rather than bobbins) and it is certainly less labour intensive than the normal method of planing down bits of wood and drilling centre holes.

These days I wind transformers on an AVO Douglas coil winder. These are very old and when they turn up they often have parts missing. It took a lot to get mine going. I made up a control circuit using two PICs (one isolated and one on the high side), to drive a washing machine motor via a triac.

When I originally rewound the TV22 line output transformer, I did it myself, making use of a winding machine at a local transformer manufacturer (long since defunct). They only had enormous manual feed machines, which made trying to get the wire neatly side by side a real pain.
It was a very odd set up with the boss having started up on his own after being employed at another winding company. He had equipment that was too big for the kind of contracts he had and little understanding of transformer theory.
This is relevant because he sourced new laminations for my transformer. He ordered a material much thicker than the original, stating that it would make no difference (he was wrong there) and also opted to save money not having the mounting holes punched. His idea was that to simply drill through the whole lamination stack in one go, ignoring the fact that this shorted all the laminations together. These two things would not be a problem at 50Hz, but at 10kHz it was.
They guy was also struggling with a large contract winding switched mode transformers to a customers specification, he only tested them at 50Hz and the customer rejected loads of them due to excessive noise. He blamed them for running them at high frequency! It came as no surprise that they didn't stay in business for long.
Also for this reason I have loads of the "I" shaped version of the TV22 line output transformer laminations (early sets had "T" shaped ones), that aren't much use to anybody.

Your use of an Arduino for the wire feed guide could mean it also has the potential to work as a wave winder as well.

I'll stop waffling now.

Cheers
Andy