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PostPosted: Tue Dec 11, 2018 11:21 am 
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A project that will be on my bench soon (a few builds to wrap up first) is this 1918 Gibson F2 Mandolin.

My good friend has had it for years, and bought it knowing full well that it had a repaired headstock. Turns out it was a poorly repaired headstock, and over the past couple of years the crack has begun opening up. Its unusual that it opened up given the apparent use of dowels/pegs, and I'll need to do some testing to know what adhesive was used (I hope hide glue and that it just got too warm at some point and started to open up).

For long term stability I'm inclined to replace both the ebony headplate and the back strap. This would involve careful removal of the original inlay or recutting a new "the Gibson," but would provide a very solid repair that would be much, much less visible. Given the current state, a well executed headplate replacement shouldn't have any additional negative impact on value.

Have any of you had success removing and saving Gibson headstock inlay? (I've removed more simple fretboard inlay)
How thick is this era inlay?

I will also likely add splines to reinforce the headstock prior to replacing the headplate/backstrap.

I'm just starting to map out my approach, and welcoming any thoughts or recommendations.

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PostPosted: Tue Dec 11, 2018 11:22 am 
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PostPosted: Tue Dec 11, 2018 11:26 am 
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Or did they just paint the black headplate/backstrap?

I'm picking up the F2 later this week.


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PostPosted: Tue Dec 11, 2018 5:45 pm 
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Something tells me that is not the original head stock. That treble scroll looks funny. They were cut out a lot farther than that. "The Gibson" looks a little too smooth also. They were hand cut and looked that way.
Check out the "Mandolin Archives"...

Image

Most overlays top and back were black dyed pear.


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PostPosted: Tue Dec 11, 2018 5:55 pm 
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Agreed - something does seem fishy.


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PostPosted: Tue Dec 11, 2018 6:15 pm 
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I should add that I always used ebony, the trick is to find it 4" wide. Were it mine to do, I would also dip the tuners in PC etchant and rinse. They just look too new. I'd probably leave off the bushings too...


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PostPosted: Tue Dec 11, 2018 6:19 pm 
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Haans, did the F-series Gibson mandolins of the teens have Ebony front and back on the headstock?


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PostPosted: Tue Dec 11, 2018 8:00 pm 
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Brazilian Rosewood
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Nope...not as far as I know.



These users thanked the author Haans for the post: dpetrzelka (Tue Dec 11, 2018 8:40 pm)
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PostPosted: Tue Dec 11, 2018 8:07 pm 
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dpetrzelka wrote:
Haans, did the F-series Gibson mandolins of the teens have Ebony front and back on the headstock?


From my understanding they used a light colored wood and then stained it black. Holly I think? I could be wrong EDIT: I just saw where Haans had already clarified this, my mistake!



These users thanked the author DanKirkland for the post: dpetrzelka (Tue Dec 11, 2018 8:40 pm)
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PostPosted: Wed Dec 12, 2018 8:59 am 
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I agree, that logo is way too neat for period Gibby work.....Image

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PostPosted: Wed Dec 12, 2018 9:40 am 
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I should have expected it, but am still surprised by the variability in those early Gibson Mandolin headstocks and inlays.
With the two examples here, and looking through the Mandolin Archive, the inlay is set at different angles, the placement of the dot above the "i" jumps around - sometimes nearly touching the bottom of the "T," others not.

This example from the Mandolin Archive, shows a treble scroll that appears partially, partially carved?
http://www.mandolinarchive.com/gibson/serial/7135
Image



Something does seem off about this specific one, I'm looking forward to examining it more closely.
Would any of you know the range of headstock thickness Gibson usually used on these F-series from the teens?


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PostPosted: Wed Dec 12, 2018 3:43 pm 
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Brazilian Rosewood
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Brian, that's more like it. I never was much of a fan of that CNC look.
Dan, there is something wrong about that inlay too. Might be paint. Many "The" parts had the dot cut with it as the photo I selected. Others used a dot like Brian's example. Also, the example you chose has half the "b" missing. so it looks like "Guson". Also have to remember that Orville sold it all to Gibson investors (yea, they had 'em then too) and was hand building them till 1906 or whatever...too lazy to look it up.

Many, many Gibsons had the treble scroll knocked off. At some point, a circular piece was inlayed into the mahogany or maple neck part that was probably around 1" in diameter to make the scroll stronger. This particular 3 point looks like a bad repair of a knocked off scroll.

I used to have a teens F2 a very long time ago, but all I have now is a 1921 F4. Most all the headstocks were tapered from nut to tip that I know of. My F4 has the mahogany neck and without top veneer or bottom, 1/2" at the wide part near the nut and 7/16" at the tip. Top veneer is almost 1/16" and bottom is about the thickness of card stock. I also noticed after all these years that it actually has no dot at all!

Hope that helps...

On thinking about it a bit further, I would probably make a diagonal joint by cutting off the peghead and splicing a new peghead center onto the smoothed neck part of the break. Both top and bottom veneers have enough left to strengthen the glue joint. I would cut the taper in the peghead blank. Then I would make an accurate top veneer from ebony and glue it on. I would add the back veneer after I had cut the mahogany to the shape of the peghead and glue it on (taking off the rest of the backstrap) and proceed from there. the mahogany center of the peghead should be soft enough that you could cut it to match the veneer easily with a coping saw and then sand by hand the rest of the way. Don't forget to bevel the top of the peghead as they were beveled and tapered...the back was longer than the top and the faces of the two sides that make the point taper back to front.

Image

Here is the other side. What's happening here is that the cuts are being made perpendicular to the fingerboard.

Image

Hope you can see this but the slant of the tip of the headstock, the bass curl and the wide edge before the nut, all straight lines are also tapered from back to top.
Cut the inlay by hand, you can't do worse than Orville! Blend the dye stain and French polish to finish off.
This has the makings of a very nice repair...



These users thanked the author Haans for the post: dpetrzelka (Fri Dec 14, 2018 6:55 pm)
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PostPosted: Fri Dec 14, 2018 7:30 pm 
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Hans, I greatly appreciate the advice, and it sounds like a great plan to follow.

For the finish - this neck has clearly been over-sprayed, as there is hand wear that is under gloss finish. I'll need to sort out what they sprayed. Would the original finish have been Shellac/French Polish or nitro?

Do you have a recommendation for a source of accurate templates for the heastock shape and inlay?


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PostPosted: Sat Dec 15, 2018 5:11 am 
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dpetrzelka wrote:
For the finish - this neck has clearly been over-sprayed, as there is hand wear that is under gloss finish. I'll need to sort out what they sprayed. Would the original finish have been Shellac/French Polish or nitro?


1918 is a bit too early for nitrocellulose finish. I believe Gibby used a varnish on these originally.

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These users thanked the author B. Howard for the post: dpetrzelka (Sat Dec 15, 2018 11:20 am)
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PostPosted: Sat Dec 15, 2018 8:27 am 
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Brazilian Rosewood
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They used oil varnish with FP over. I used JOHA (Jacob Hammerl) oil varnish with JOHA spririt over. Since it has little to do with tone, you could use FP.

https://www.internationalviolin.com/Pro ... ound-clear

Don't have a template for an F2. Try Roger Siminoff.



These users thanked the author Haans for the post: dpetrzelka (Sat Dec 15, 2018 11:20 am)
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PostPosted: Sat Dec 15, 2018 10:09 am 
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Brazilian Rosewood
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...or, just enlarge the photo I provided up there until the tuner pegs are the right distance apart.


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PostPosted: Sat Dec 15, 2018 10:48 am 
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I was just looking through my bookshelf for another reference and found Roger Siminoff's Ultimate Bluegrass Mandolin Constrction Manual -which includes F5 style head stock drawings. I'll plan to add the scroll strengthener that he recommends. I need to check my own bookshelf more often.

Looking on Siminioff's website, I see he references a different headstock for the F5 vs F4/F2
Image
Do you know the difference between the headstocks on the two model groups?


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PostPosted: Sat Dec 15, 2018 3:03 pm 
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Brazilian Rosewood
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F5's are skinnier. By the looks of it, 3rd one is the H5 mandola.

Do this: go through the archives and find all the headshots of F2 pegheads. My old one looked quite similar to the one I picked above. Find the one you like. Scale it up so that the tuner posts are .906" apart. Done.

F5...

Image

F4...

Image

H5...

Image



These users thanked the author Haans for the post (total 2): dpetrzelka (Sun Dec 16, 2018 9:43 am) • Clinchriver (Sat Dec 15, 2018 6:12 pm)
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PostPosted: Tue Dec 18, 2018 3:27 pm 
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Haans,

I've got a pretty nice peghead shape drawing coming together. Since I'm doing it as a vector drawing, I may just CNC the head plate before gluing on, then cutting peghead mahogany body and back strap to match. (Cut perpendicular to fretboard plane). I'll share the drawing when complete, just in case others would benefit.

For "the Gibson" inlay, it appears each luthier at Gibson was cutting their own version
- is there an accepted standard?
- white MOP.
- originals have clear saw marks, I know it would be appropriate to match that fidelity, slowly coming to terms with that.


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PostPosted: Wed Dec 19, 2018 12:12 pm 
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I need to make a few more refinements, and verify some of the measurements, but getting close on a nice outline for an F2 headstock.

Image


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PostPosted: Wed Dec 19, 2018 12:29 pm 
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I did attempt to get in touch with Roger Siminoff, but realize he retired a couple of years ago. Amy and Kali took over Siminoff's website, and run Straight Up Strings, but I haven't heard back from them about his drawings for his G-1 (F4/F2) headstock.

Unfortunately links to their web store for his Pro series plans are also broken.


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