vinyl glazing

I'm afraid there isn't any tool made to roll in vinyl glazing. Glaziers just use their hands. When installing vinyl snap in, we always start at the bottom. Some manufacturers built a ledge for the glass to rest on that makes a space so you can slide the snap in under the glass. If not, you can set the glass in the open framed with a small vinyl shim to raise the glass slightly so you can slide the snap in under the glass.