I need to ream a 12" carbon fiber grip with a urethane foam core. Do the Flex Coat reverse pilot spade bits work well on foam cores? I have only seen those discussed for use with cork and somewhat EVA. If not, what other options are there besides my CRB reamer set?

And what if the diameter of the blank is larger than the inside diameter of the carbon fiber that wraps over the end of the foam? Will the reamer cut that or will I need to do something else to slide that over the blank?

Thanks in advance.

The foam cores are very light yet rigid and therefore ream easily. A tapered reamer, in the proper size, will do the trick in half a minute, or less.

Do remember to blow out the reaming debris before test fitting. The foam bits can be sharp and will easily scratch a rod blank finish.

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SLOWLY is the key!!

Tapered reamer and SLOW, SLOW, SLOW

You might want to chamfer the hard ridge where the reamer will be entering the grip with a drill bit large enough to get rid of that hard ring. If this is not done, it's very easy to over ream the foam.

Lynn is exactly right, that hard ridge needs to be opened up or as he says, it will be very easy to over ream the foam in the grip. To be sure that the drill bit doesn't screw itself in I take masking tape and wrap it around the bit just a little past where the tip transitions to the flutes on the bit. I usually go about a 1/16" past the tip. I make sure to wrap about an 1/8" thick worth of tape just to make sure it's going to stop.

And as everyone has said, go slowwwwww, and check often. The foam reams extremely easily. Especially if your reamers have a heavy grit abrasive on them. I would also caution you that once you get it to the right size, do not keep testing fitting it. Putting it on and taking it back off the blank a few times after reaming it to its initial fit, will result in the grip going from nice and snug where you want it, to a little loose. Also if the grip has a tenon, putting a butt cap on and taking it off a few times will cause it to loosen a bit.

The grips are very strong, but the bare foam is what I would consider, somewhat delicate. At least that has been my experience with them. I love them though. I'm waiting on a blank for my next build and it will be the 4th build I've done with them.