This maybe well know in sewing circles, but having found it in my grandmothers sewing machine I thought it was too good an idea not to document and pass on in case it isn't
Step 1: What Is It?
My grandmother was the village seamstress and clearly used a lot of thread we found several commercial sized cones of it in her sewing cupboard. With her sewing machine today I found this one with an adapter to make it work with a standard home sewing machine.
Step 2: How Was It Done
The adapter is very simple. She appears to have taken an empty wooden cotton reel and carved off one lip and trimmed the body of the reel a little to make it a tight fit in a commercial cone of thread