Tried my hand at making two concept drill bit reamers yesterday. The problem that I encountered was that the stem on the bits would not go into the hole in the grip. It still took a few swipes with a rat tail file. However, once inserted the drills did their job in no time at all. You will still need your grit reamers to fine tune the grips to fit your rod blank but that will only take a swipe or two to do finish the job.
When you glue a grip some of the glue will leak into the cork hole and that is the reason the drill stem would not fit. Once filed smoothly, the stem fit and it only takes a couple of minutes to ream out a grip. This is a great tool.

Are you talking about the pilot bit cork boring tools we outlined plans for in RodMaker? Heck of a tool.

The minimum bore size you can work with will be limited to the OD of the spade bit you've purchased. But many in the 5/16th inch range can be had. Others are closer to 3/8th inch.

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Yes Tom, the bits in the RodMaker are the ones I made. The problem that I had was the stem going in the hole of the cork rings. The spade size is 3/8" and almost a perfect fit on a fly rod that I am building. The project that I am working on now is to see how cheaply I can build a 6 wr. fly rod. I bought a fly blank from Andy about a year ago for about $20. It is an Allstar IM6 blank that they used to make for other OEMS. The reel seat is a green aluminum Pac Bay seat to go with the color of the blank. The cork grip is also a Pac Bay bamboo burl grip that Donart and Cabela's sells for $9.00. The total cost will be around $55.00. Not too bad for a rod that I will use for bream fishing. I ordered the full wells grip with recessed rear cork to fit the reel seat and it fit perfectly. The one thing that I do not like on that grip is that the diameter drops of the grip two cork rings forward of the front end drops down to 21mm's. The full wells without the cut out drops to 24 mm's and looks and feels a lot better. I wish that I could buy the bamboo burl rings to turn my own grips. They look very nice with cork finish on them.

Tom
About 10 years ago I had a set of piloted step reamers made at the local machine shop. They're 12 inches in length start at .250 of an inch and go up .010 per step. Since I ream each cork ring to fit the blank I get a perfect fit and the rings are not chipped around the hole, which I find hard to do with a hand reamer. I do the same thing when I inlet the cork ring for my fly rod handles perfect hole and perfect fit evereytime.

These aren't reamers, but actual boring bits.

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