The insole is an extremely important part for the fit of the shoe. Most shoe makers buy the pre-made insole that goes with their chosen last, not Bill. A pump traditionally includes a structural support spanning from the heel through the arch. Most often that structure is provided with a metal insert, but we learned how to do this with fiberglass.
The process begins with an insole component that runs the full length of the shoe with an insole board that spans from the heel to the curve of the sole. These components will eventually be covered. You are viewing the side that will be inside the shoe.
Next we cut the fiberglass and prepared it. With our insole tacked to our lasts. This consisted of cutting the fiberglass, connecting it to the insoles with epoxy and adding foil to protect the insole from the heat gun. Restaurant grade foil was stapled onto the insole from the edge of the fiberglass out.
Our last step was to heat activate the fiberglass to bend it to the insole shape. This took several minutes. When done the insole and lasts were wrapped with elastic and left to cure to hold the shape. Note-several of our fiberglass pieces didn’t take, most likely from a faulty mix of epoxy. In these cases (mine was one) a metal shaft was used for the sake of time. So I have on shoe with the fiberglass shaft and one with the metal.