Just received a new order of composite cork blocks. 1 1/2” x 1 1/2” x 12”. I have a lathe which I put on a 8” or 14” drill bit. But not all cork blocks are straight. So I was going to make a 3 sided square jig, to hold it straight while drilling. Then after drilling 1/4” hole then use the Flexcoat reverse drill bit, then epoxy arbors inside the cork composite to reduce the weight. I’m going with 18 to 22 arbors depending on grip size.

I’m sure someone has done this and has advice.

Thanks

Mike

Mike,
I am admittedly a bit puzzled and hopefully you can explain.
First, if you clamp the (curved) cork blocks in your “3 sided square jig, to hold it straight while drilling”, and then center drill it to size, when you release the clamp, won’t the block return to the original curved state? Even if the foam arbor is inserted before removing the clamp, is the foam rigid enough to hold the cork perfectly straight? Assuming the cork blocks are ~ square and will require shaping into a round circumference, why would it matter if they are a little “bent” to begin with? In other words, why not just straight bore the curved blocks?
Second, to consider going through so much effort, you must have calculated how much weight you will save. Granted, the foam core might be lighter than cork, but how much? Did your calculations include the weight of the epoxy to bond the foam into the cork and a winding check, epoxy ramp or whatever to conceal the foam core opposite the seat?
I don’t mean to be pessimistic or play devil’s advocate. I am simply here to learn.

Mark Talmo
FISHING IS NOT AN ESCAPE FROM LIFE BUT RATHER A DEEPER IMMERSION INTO IT!!! BUILDING YOUR OWN SIMPLY ENHANCES THE EXPERIENCE.

I use block cork (composites) frequently in making custom fly rod grips, and the following suggestion gleaned from my experience.

1.) Do not bore the entire 12" unless that will be the length of your grip. Shorter material is easier to bore straight!
2.) Do not bore the 3/4" all the way through, bore the end to fit the blank diameter.
3.) U sue a 3/4" Forstner bit to bore for the 20mm foam reel seat cores I use.
4.) I do all this before turning the grip shape and diameter.
4.) Doing this reduces the weight of the grip substantially.

Let me clarify,

I have the 3 sided jig and a 4th side that pushes the block square. I totally agree I should bore as short a piece as possible. I did experiment with this, by cutting into 3 four inch pieces and marking these sides, drilling on a drill press, then glueing back together. The cuts were hard to see.


Just always searching for the best way.

Thanks,

Mike