Hi Rod,

I usually take a plasma cutter and knock a rough 2.25” hole in the center of the disk blade if I’m using a 2” mounting pipe for the duck box. I then take and drill a .375” hole or similar hole in the mounting pipe where I want the disk blade to sit. I insert a 3” - 4” long bolt into the hole so the disk blade can’t slide down the pipe any further than the bolt. I think the disk blades I’m using are around 20” - 24” diameter but that isn’t really critical, a blade as small as 12” would likely work. Thanks.

Bryan