[AdrianH]

Thanks retailer, I think the brown colour is not a varnish or lacquer as it is the colour even in the centre of the transformer, I should have done this before, so here is a picture a bit late sorry.

Thanks for the answer on the margins. I have purchased a cheap winder from Ebay, it was less than £19.00 (UKP). It needs a bit of fettling to make it work a little better and I have done some work on it, I am probably not going to be winding many transformers, but it will certainly save a lot of effort. I am on the look out for a small variac and it will probably take a while to get one at a reasonable cost. I find it strange that I can get small transformers cheaper then buying laminations and bobbins separately, I guess down to scale.

Adrian

I should say that that of the 6 laminations shown, the three on the top row are very similar finish, being a brownish colour and the 3 bottom ones look more like plain mild steel to me although they are probably not.

Sizes are for the two top larger ones 1 7/8 x 1 1/4 inch
The middle top is the size I used on my audio transformer is 1 5/8 x 1 1/16 inch
The three smaller ones are 1 3/8 x 15/16 inch and that transformer was 1.5VA 15 Volt at 100mA.