I am sending you this document to support and illustrate what I did in FWT, LLC.
The specs called for 1 1/8” holes but we always received the material with a 1 1/16” holes, and we were enlarging the holes with a reamer – which does not produce a true round hole
Most of the time the operator went off the round shape, and had to fill it with welding material and work on
it again
Annular cutters come with a ¼” pilot pin which serves as the center for the annular cutter to cut a round hole without wobbling. Drilling a ¼” hole for the pilot pin is the way to go.
But in our case we already had a 1 1/16” hole and the ¼” pilot pin was useless for us.I envisioned and fabricated a 1 1/16” pilot pin to keep the annular cutter from wobbling.
And it went from an average of 24 minutes per hole to 28 seconds, flat.We’re making 50 holes in the time we were making 1.