For strengthening fur, a piece of cotton cloth - available in every weight from handkerchief to canvas fixed in place with white wood glue - PVA I think it is, but the non waterproof sort, will protect the back to whatever extent is needed, as long as you make the right choice of cotton cloth. You can then draw the shape on the cloth, and if you ever need to remove the backing a wet sponge left on it for a few hours will reliquify the glue and allow the cloth to be removed without damage. Several spongings and it will be as though never glued at all.

The white glue is also useful for sealing the edge of leather or pelt where there is some separation or for making repairs if there is a nick or slice in just the wrong place. Sometimes there can be a softer place in the skin and gluing on muslin or a strip of bandage can even it up.

If you are doubtful about anything then cutting out a tester in sturdy cotton and sewing it together either by tacking, or some sewing machines can do chain stitch which is very easy to remove, then you can make adjustments and retry until perfect.

The cotton could then be kept for future patterns, or you could make a more rigid pattern from it, or some of it could be used for backing very light fur or leather.


Just in case - when cutting fur, I use tiny scissors and work from the inside, slowly snipping through just the skin, so as not to cut the hairs. Once the piece is cut out I then put it down fur side up and trim the very edge to make a fur free seam allowance for sewing