On 06/05/2020 08:03, Graeme wrote:

Going back 50 years, I used to use a large loose leaf book, the outer
being two thick black boards, the two joined by a pair of thick straps.
One outer had a key hole, the key being cranked, and operation of the
key caused the straps to be drawn into the cover.Â* Pages had a special T
shaped cut out, which was arranged around the straps, the key operated
which tightened the straps, securing the book.Â* Unwinding the key
released the straps, enabling new pages to be added or old ones replaced.

What I can't remember is how the cut outs were formed in each sheet of
paper.Â* Presumably something like a standard hole punch, but larger.

My Google-fu is having a day off.Â* Any idea what that type of binder was
called?

Try a junk shop.

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