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I used my circle cutter from LMI for the first time the other day. The blade cuts good, I made a bunch of cuts a little less than a mm deep for the rosette, and cut soundhole out. I put the wooden rose in the middle that I took out of the piece that was going to be the belly, until it started splitting all over.

But it wasn't all easy.

I had to fix the tool first.

It stopped about 1/4" before it should have. It is even worse on the big end; but I'm not worried about huge holes. This is only a 47mm sound hole. I stopped, to make sure it would work after cutting the outside of the inlay; and it wouldn't the way it was.

If I had a little mill it would be simple. I had to use a file, and stones. For some reason the end mill on their finish cut didn't cut the entire length straight. I have no idea what they did wrong. It just fades away a couple thou a quarter inch from the end.

But I fixed it.

I like the tool. It's quiet and doesn't make dust.

The other tool is one I've had for a little while, but keep forgetting about. 3X prescription glasses, adjusted for astigmatism and everything. Those things are AMAZING. I smoothed the inlay out on the belly, and felt a little ledge. It wasn't as smooth as it looked. "Ah, I have glasses, don't I?"

Wow. What a mess. Now I see why nearsighted people are finicky about details that I CAN'T EVEN SEE! With 3X full field vision, I can see them.

I have more work to do.

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Why be normal?

It's a blessing and a curse. But mostly a blessing.

My camera in macro mode can see even smaller details. Handy in electronics work for reading the micro text on some chips.

I think that circle cutter blade is the same one used in the gramil. Somebody is going to have to take up the mantle of making those things now that LMI is gone, and it may be me. I hate to think of new builders getting started with no hand tool option for cutting binding channels.

Speaking of which, my latest tool acquisition is something I've wanted for a long time but didn't know was available: riffler files! Gramil-cut channels are always a little rough, and a rectangular needle file smooths them to perfection, but can't get into the waist and cutaway curves. I'd heard of riffler rasps, but all the ones I'd seen looked like coarse rasp teeth on 3-dimensional shapes, whereas I need fine file teeth and a plain rectangular shape. I had to buy a whole set to get this rectangular one, but for $15 I can't complain. This is what I bought (I got the package in the bottom image, which says riffler rasp set, but actually has file teeth) https://www.ebay.com/itm/275559797534
The radius of curvature is slightly tighter than my 3" bending pipe, so it should be able to get everywhere. Although the last 1/4" or so at the tip is straight (presumably held by pliers to bend it), so I may have to cut it off to keep from getting in the way. I haven't actually tried it yet, but I do have a headstock that needs binding...

Interesting; tool wear would be my guess.

My first three guitars were StewMac kits, I bought them at the same time. All three had a hump in the center of the long dimension, running the length of the dovetail mortise in the neck block. You could see it clearly with a straight edge. You could also see it clearly with chalk after hours of attempting to fit the neck tenon. That could be easily explained by tool wear in the router bit (cutting edges were worn and shorter in that area of the bit). I did communicate that to them, wonder if they followed up.

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Measure Twice,

Karl Borum

If it was wear, the surface finish wouldn't be so good. I would undercut the ends with the rougher, so the finish end mill wouldn't run into the corners. Even that doesn't really explain it.

Talking about fixing tools. I have all the stuff finally to fix the bandsaw. I was setting the guides and thrust bearings yesterday, and I noticed a couple were VERY noisy when they were fully on the blade. They are worn out. They still turn, so I thought they were good.

Luckily I bought a pack of 10 of the little bearings! But now I have to get the thrust bearing out of the block. I broke the lower one. So I looked around and found a piece of 3/8" steel. Turned the end to 3/16" and sawed it off.

It worked great.

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Why be normal?