Celastic toe boxes, shaped

The “toe box” (or “toe puff” in Europe) is a stiffener that holds and reinforces the toe shape. It’s inserted between the lining leather and the upper leather.

Toe boxes can be made of:

Leather, which is molded while wet and then sanded to shape

Celastic, which is fiber/synthetic material that’s activated by solvent, which makes it pliable and moldable while activated but dries hard

Thermal, which is plastic that’s activated by heat, which makes it pliable until it cools

There are very strong opinions in the shoe and boot making community about the virtues, benefits, and traditions of each of these materials. My opinion is that if it holds the toe shape and the back edge blends seamlessly into the lining so you don’t have a ridge showing on the finished boot/shoe, you’ve done a good thing.

I personally use Celastic. I’ve seen boot makers activate their celastic in margarine tubs of solvent and then reach down with their bare fingers into the solvent to grab a snotty disgusting piece of celastic, but I don’t do it that way. I lay my celastic toe boxes on a cookie cooking rack, drizzle a blend of contact cement thinner/acetone over them, and don’t pick them up until they’re dry to the touch but still pliable. I do the rough shaping on my finisher and the final shaping by hand. You need a light touch with the sanding with celastic because you don’t want to sand it all away. A more accurate way to describe it would be “gently shaping.”