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Howzit all?

I'm soliciting opinions here. I am building two guitars: an 000 and an OM. The OM is going perfectly but I'm beginning to suspect the 000 is cursed.

First, I was routing the top binding ledge with my Fleschman-esque jig. I did not properly secure the bit and it began to slide down. Luckily, I caught it before it got too out of hand but the ledge was way to deep.

So, I had to remove the top and thin the sides down by about a half inch. Not a huge deal but major surgery and a time killer. Unfortunately, I cracked the top in a manner that I did not feel good about salvaging so I began to build a new top.

Last night, I was cutting the rosette channels on the new top when I had another equipment malfunction. This one wasn't my fault though! See, I use a flywheel cutter with custom ground cutters. Well, I found out the hard way that this unbalanced configuration can cause the entire chuck to come loose from the drive shaft. The drive shaft (Craftsman) is slightly tapered and the chuck is, apparently, just pressed onto the shaft.

You can guess the rest. The chuck came down the shaft with the cutter and half of the rosette is cut clean through the top. It jammed and this is why a complete circle wasn't cut through.

The underside is a little ragged but nothing a little filler wouldn't cure. On the topside, the channel is clean. I inserted the purfling and once inserted, you cannot see the problem.

So, my question is two part: 1) If I go ahead and carry on as if nothing happened, will the soundboard integrity be compromised? In comparing the old top, which was braced, I note that the braces cover at least half of the affected area (the half that cut through is the tail half) so, there would be a bit of purfling visible right at the juncture of the X formation. 2) If we assume that the soundboard will be structurally ok, then is this a deal killer when I go to sell the instrument? Anyone with an inspection mirror is going to see the problem right away and I might look like a hack.

Obviously, I hate to start on a THIRD top but..... What do you think?

I'm one of the people who fits the patch.

I has a pignose amp drop THROUGH the soundhole of an old epiphone I had. Ply top so it held (ish!!) if it had been a solid cedar top it never would have survived.

George Lowden does the patch too, so some good builders are at it as well!!

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Sergei deJonge also doubles the top around the soundhole area. It looks great and he also feels that it improves the sound.
So, I'd go with the 'full patch' treatment with no regrets if I were you.
Cheers
John

[QUOTE=mconk]   

Well, I found out the hard way that this unbalanced configuration can cause the entire chuck to come loose from the drive shaft. The drive shaft (Craftsman) is slightly tapered and the chuck is, apparently, just pressed onto the shaft.

[/QUOTE]
You probably know this already, but for info:
The arrangement you describe for your Craftsman is pretty standard in most drill presses. Often the chuck is friction-fitted to an arbor, which in turn has a Morse taper which mates with the spindle. It's amazing they work as well as they do; it would be nice if drill presses had threaded draw bars the way milling machines do, to keep the arbor (and chuck) in place.
I once had this problem with a drill press; once the arbor vibrated out, it seemed to damage the taper surfaces enough that I could never rely on it again. Hopefully you will have better luck.
Cheers
John

Wells-Karol jig???