I was machining zero clearance plates for my BT3000 and wanted to cut the slot by installing the ZCTP and raising the spinning blade into it. The warning being that if the plate is screwed down and the blade trapped you can break your belts when starting the saw.
So there has to be clearance between the top of the blade at its lowest position and the bottom of the plate, and/or a relief cut in the plate if the pate is thick.
The plastic ZCTP blanks form Ryobi are 1/2 inch thick and have an arched relief in the blade area. I was using a 1/2" thick piece of flooring.
I measured the blade clearance top tip blade fully lowered, to the top of the table

and I could get a 3/16" setup bar with clearance but a 1/4" setup bar touched both sides so at least 3/16".
I put in a relief of 0.25 deep, but I think I'm going to have to increase it to .375 leaving only 1/8th inch at the apex.


Also, the three hole pattern for mounting the ZCTP puts the hole in the thinnest part, very close to the edge, you can see on my plastic ZCTP where it has broken out. I decided to use the four hole pattern which is thicker area farther from the edge.
So there has to be clearance between the top of the blade at its lowest position and the bottom of the plate, and/or a relief cut in the plate if the pate is thick.
The plastic ZCTP blanks form Ryobi are 1/2 inch thick and have an arched relief in the blade area. I was using a 1/2" thick piece of flooring.
I measured the blade clearance top tip blade fully lowered, to the top of the table
and I could get a 3/16" setup bar with clearance but a 1/4" setup bar touched both sides so at least 3/16".
I put in a relief of 0.25 deep, but I think I'm going to have to increase it to .375 leaving only 1/8th inch at the apex.
Also, the three hole pattern for mounting the ZCTP puts the hole in the thinnest part, very close to the edge, you can see on my plastic ZCTP where it has broken out. I decided to use the four hole pattern which is thicker area farther from the edge.

LCHIEN
Loring in Katy, TX USA