Filling in mahogany gap.

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Mike Perez
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Joined: Sat Feb 19, 2022 1:24 am
Location: Southern Ca

Filling in mahogany gap.

Post by Mike Perez »

Hello.
I just plugged the rear pickup cavity to an old solid body electric guitar.
I used poplar and made it just shy of the back surface so I could inlay some thin mahogany for a flush surface.
The mahogany came out okay. I had some gaps between the cavity and the thin mahogany piece.
The cap was crisp but the old recess was hand routed and as you can see, a bit crooked.
Because the old finish was black, you can see black in the gaps.
I plan in cutting away some of the black material and filling it in with mahogany dust and glue, but the Titebond will not allow any stain.
Would a different glue work better?
I plan on staining it and clear coating it.
At this point mahogany dust with yellow tinted glue is better than black streaks.
Any suggestions would be apprenticed.

Thank you,
Mike

Guitar back fill.jpg
Mike Perez
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Location: Southern Ca

Re: Filling in mahogany gap.

Post by Mike Perez »

Would something like Timbermate be a simple solution?
Marshall Dixon
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Re: Filling in mahogany gap.

Post by Marshall Dixon »

Mike Perez wrote: Thu Sep 07, 2023 9:40 pm Would something like Timbermate be a simple solution?
I don't know if this will help but Titebond can be stained a gun metal blue color with tincture of iodine. I've done it where it came out quite dark after several applications though not a true black.
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Bob Gramann
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Re: Filling in mahogany gap.

Post by Bob Gramann »

Why not rout a little shelf around the opening and make the mahogany filler fit that rabbet? Any gaps would be the same color and wouldn’t require filler to look professional. Timbermate will look like you pushed putty in the gaps and will shrink later and leave depressions.
Mike Perez
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Location: Southern Ca

Re: Filling in mahogany gap.

Post by Mike Perez »

Bob,
Do you mean something like this, where I can inlay some strips of mahogany into the route channel?
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back route.jpg
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Bob Gramann
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Re: Filling in mahogany gap.

Post by Bob Gramann »

Yes, but much smaller and closer to the original outline so that you don’t go out to the edge. It will look better if you redo the mahogany patch as one piece rather than inlay strips. Making a template to guide the router will increase the odds of your success. You can make the template several times until you get the shape right before you route the guitar.
Mike Perez
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Joined: Sat Feb 19, 2022 1:24 am
Location: Southern Ca

Re: Filling in mahogany gap.

Post by Mike Perez »

I think you're right.
I was trying to save as mush of the original wood and that just made the "patch" too complex.
I will route more and square it off to make a tight fit much easier.
The edge doesn't matter as I am going to add binding to both sides.
'Can't chose between white plastic, curly maple or rope binding.
I'm leaning toward rope binding.
Thank you.
Mike Perez
Posts: 56
Joined: Sat Feb 19, 2022 1:24 am
Location: Southern Ca

Re: Filling in mahogany gap.

Post by Mike Perez »

I decided to take the advice and simply made a new cap.
A simple template and some sanding gave me a near perfect fit.
The grain was close but not an issue.
The body has a light shellac finish but not the cap.
Oh, after seeing a mahogany acoustic with rosewood binding, I think I might go that route.
Thanks again.
Attachments
Back.jpg
Back cap.jpg
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Bob Gramann
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Re: Filling in mahogany gap.

Post by Bob Gramann »

Nice fit. Congratulations.
Mike Perez
Posts: 56
Joined: Sat Feb 19, 2022 1:24 am
Location: Southern Ca

Re: Filling in mahogany gap.

Post by Mike Perez »

Back.jpg
With a few coats of shellac.
Very different grain but the fit was spot on.
African (current) on top of Honduran (1982)
Battle scar.
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Bob Gramann
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Re: Filling in mahogany gap.

Post by Bob Gramann »

A few months of light exposure ought to darken the patch considerably.
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