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I hope this helps someone!

I was sanding the top of this ebony OM when disaster struck.

My home made purflings were thin in spots and I sanded through them. To top it off, my repair was ending up pretty horrible. I tried to rig up a 1/32nd inch blade to excavate some new lines and touch up the purflings, but it was not working out very well. My usual fly cutter method of installing rosettes wouldn't work on a completed instrument, as the top had been braced and curved already, plus how would I center it?

I had to come up with something. Here's how it was looking:


Then I saw that thread where the guy had attached a block to his Stew-Mac rosette cutter with a razor blade for cutting the lines. It looked light enough to manipulate on top of the completed guitar, and seemed to be a pretty sturdy tool so I got one.

First I had to find a way to center the tool in the completed soundhole. I couldn't just drill into empty air and set the pin, so I made this plug.
Here's how. First I installed the pin and rough cut a circle with my dremel. I didn't cut all the way through, I wanted a lip. Fortunately, it was the outside ring that needed repair, not the inside, otherwise I wouldn't have trusted the soundhole to support the plug while I was dremeling away the surrounding support surface and would have been forced to make some form of internal support. As it was, no problem:


Then I bandsawed around it and trimmed away the excess, finally chiseling away the excess to leave an even ledge around the plug.


Last, I fitted the plug tight into the soundhole so it would not move at all. It was delicate, as the plug had to be absolutely stable and tight to not move in the slightest, yet not so tight that it was risking damaging the soundhole upon removal. Mission accomplished!


Now I was able to route and install new purflings on the completed soundboard around the rosette.
Here's the finished project! I had to install extra lines around the perimeter because of my crappy initial repair attempt, but surprisingly, to my eye it doesn't look unbalanced. I'm pleased with the result.

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Old growth, shmold growth!

Nice work. Thanks for sharing.

these are not mistakes but design enhancement possibilities

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Nice save!

Whisperer :
Super recovery..............!!! Just love your rosette.............this type seem to be in vogue right now ....a bit of work but a real super break from tradition...!!!! CONGRATS.
Tom

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A person who has never made a mistake has never made anything!!!

+1

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Thank You and Best To All

I made a plug that looks exactly like the one you have made for the same repair when the purflings came out stripping for a re finish. Glad to see that worked so well. Did you need to go a bit deeper to compensate for the arch in the top, and if so how much?

I routed down 1/16 inch at the deepest spot, It didn't seem to vry more than a 64th around the perimeter. I figured tha since the top was already mostly sanded except for the final sanding that would be good as long as I made sure the purfling was seated all the way around.
I don't see myself sanding 3/64th's of the top away with the final bit.

As much fun and success I've had with the flywheel rosette cutter, I may switch to this version. for main rosette installation. I would like a better tool than the dremel for that though.

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Old growth, shmold growth!

Very well done!

Great save, Chuck.

Bob

Thanks guys!
The solution was so obvious and simple it took me 2 months and forum post on a different topic altogether to realize it.


I'm just glad it worked out.

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Old growth, shmold growth!

I did a total save a while back.
You can fit a Proxxon Motor into the Stew Mac router base. I used a drill press 1/2" drum and just sanded the threads off and a bit more till the Proxxon fit. Then I just drilled a hole and tapped for a set screw.
Turns the whole thing into a really viable and accurate unit.

Yes, it certainly was a nice save. Congratulations to you for resisting the urge to freak out and instead just studying the problem through and figuring out how to fix it. I must say I like the looks of your border lines in the "save" better than your original plan. Very well done, I say!
Patrick

Thanks!
I too like the bolder appearance of the "save".
This wasn't a commission, but rather me pushing my personal envelope by making all my own bindings and purflings, so when I sanded through, I took it more as an oppurtunity to develop my skills further in preparation for an actual emergency.
My first attempt was to try to cut the lines out by hand using a modified x-acto blade, that didn't work out to well as it also left a huge uneven gap aorund the purfling, which I attempted to fill with extra spruce from the same soundboard.
The whole thing became a mess.
I'm glad I tried it though, with this setup I think I could have replaced just the original lines, which would be useful if the scheme were more fixed or had already been approved.
Here's some more pictures of the actual guitar. the theme is Ebony and Purleheart, so the back and sides are ebony, and the bindings and purflings are purpleheart and actual ebony, not black dyed fiber, ad it has a bound sideport:

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Old growth, shmold growth!

Late arriving to this thread. A very nice save indeed. I like the rosette, and the purpleheart and ebony colors, gives the guitar a very bold look overall. Noticed you have sound port on lower bout, do you like it better than on upper bout?

I don't know which I prefer right now, actually. I'm still experimenting.

I do know that I like the sideport concept in general, and everyone who has played a guitar with one has been impressed.

I've made one guitar with the sideport up top, for a guy who has hearing aids. Compared to his guitar without a sideport, the one with the sideport is much clearer to him than the one without it, which now sounds somewhat muddled in comparison, and this one will be my second with the port on the lower bout.

I'm leaning towards the lower bout because I can make the port a little larger, which seems to make it more effective, but my sample size is small.
The guitar I made with the larger sideport on the lower bout is very voluminous and full, plenty of bass, but full mids and highs for harmonics.

Also, my female customers I've noticed tend to rest their ladyparts on the upper bout, which has actually covered up the sideport completely in one case.

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Old growth, shmold growth!

Great save & beautiful geetar!
Congrats!
mike

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Mike Collins