Gibson F-9 Heel Cap Problem (?)

[multidon]

If you just tried to reglue this yourself and pass it on to someone else as having no defect because you think you solved the problem you are fooling yourself and possibly committing fraud on the potential buyer. To me it would be like the trick they used to do to manual transmission cars in the old days. They would fill a bad transmission with sawdust and it would run fine for a while, until it self destructed. A halfway patch job on this would be the same if it was sold or traded without the defect disclosed and priced in.

Again, I say the proper thing to do is have it fixed the right way by a good luthier. And save the paperwork. Have the luthier put down on paper exactly what work was done so it can be shown to the potential buyer. Or sell it as is at a substantially reduced price to someone who is willing to put the money into it or thinks they could take it on as a project. That is how I see it.

This incident makes me wonder about mandolin structural design. In a neck like this it seems like we as asking an awful lot out of that tiny back button to stabilize a neck joint. I thought about buying an instrument from a well known maker until he told me he used a straight mortise and tenon joint, glued only, and depended on the back button to give the joint its stability. With that information I passed.

I like my Weber neck joints, which are as I understand it are like the Gibson joints when Bruce was there (Flatiron too). Someone correct me if I am wrong. But I think that the straight mortise and tenon joint, glued and stabilized by two screws, is not going anywhere.

[Tobin]

This incident makes me wonder about mandolin structural design. In a neck like this it seems like we as asking an awful lot out of that tiny back button to stabilize a neck joint. I thought about buying an instrument from a well known maker until he told me he used a straight mortise and tenon joint, glued only, and depended on the back button to give the joint its stability. With that information I passed.

I like my Weber neck joints, which are as I understand it are like the Gibson joints when Bruce was there (Flatiron too). Someone correct me if I am wrong. But I think that the straight mortise and tenon joint, glued and stabilized by two screws, is not going anywhere.

These are two different issues. The neck joint itself is just the connection to the neck block. The block connection to the rest of the mandolin is where the problem is occurring in this case.

The heel cap is not the only part that's glued. There is more area of the back (and top) that are glued to the block, where they are flat inside the body (outside the carved arch area). The heel cap does provide more surface area to the joint, but it's not the only part that makes that connection. If you look at photos or schematics of this block, you'll see how much area is actually in contact where that glue joint is.

[Bernie Daniel]

Hank. I suggest that you send an email or give a call to David Harvey in Nashville.

I'm not sure that you have a warranty claim but David has a very nice shop at his home (he recently did a lot upgrades to it and I think he can even spray lacquer etc now) and he enjoys fixing Gibson mandolins on the side. In addition he has a personal interest in making sure Gibson mandolins are right!

I had him do a tailpiece separation repair on my Sam Bush and the work was excellent and no problems since. His prices are probably not the lowest around but then you pay for the best. I dare say he knows Gibson mandolins as well as anyone and I am sure you'd be pleased with the result.

Do yourself a huge favor and have him to a complete set up on your F-9 as well -- no one does it any better.

[Bernie Daniel]

If you just tried to reglue this yourself and pass it on to someone else as having no defect because you think you solved the problem you are fooling yourself and possibly committing fraud on the potential buyer. To me it would be like the trick they used to do to manual transmission cars in the old days. They would fill a bad transmission with sawdust and it would run fine for a while, until it self destructed. A halfway patch job on this would be the same if it was sold or traded without the defect disclosed and priced in.

Again, I say the proper thing to do is have it fixed the right way by a good luthier. And save the paperwork. Have the luthier put down on paper exactly what work was done so it can be shown to the potential buyer. Or sell it as is at a substantially reduced price to someone who is willing to put the money into it or thinks they could take it on as a project. That is how I see it.

This incident makes me wonder about mandolin structural design. In a neck like this it seems like we as asking an awful lot out of that tiny back button to stabilize a neck joint. I thought about buying an instrument from a well known maker until he told me he used a straight mortise and tenon joint, glued only, and depended on the back button to give the joint its stability. With that information I passed.

I like my Weber neck joints, which are as I understand it are like the Gibson joints when Bruce was there (Flatiron too). Someone correct me if I am wrong. But I think that the straight mortise and tenon joint, glued and stabilized by two screws, is not going anywhere.

I once asked Bruce that question he said Weber neck joints were similar but not the same as the Flatiron/Gibson joints. I think he told me at the same time that they had never a Weber neck joint failure but I might be remembering that wrong.

As to your other point -- I don't think Gibson dovetail joints fail very often either. The Gibson neck joints has been around and doing just fine or over 100 years I don't think we need to start worrying about it now.

[VernBrekke]

The Flatiron/Gibson and Weber neck joints are similar but different. Although, they are both mortise and tenon joints, the Flatiron/Gibson necks that were made in Montana had threaded brass inserts that were drilled and screwed into the end of the tenon.

When we were transitioning from Flatiron to Weber (Sound To Earth), it was decided to stay with the basic mortise and tenon concept but change the brass inserts to two barrel nuts that are located in holes that are drilled through the side of the tenon instead of into the end of the tenon. The holes that are drilled through the end of the tenon, for the bolts that connect to the barrel nuts, are much smaller than the holes that were necessary for the threaded brass inserts. As a result, the pressure of the barrel nuts on the structure of the tenon, when the bolts are tightened, is distributed more evenly with the Weber system than with the threaded brass inserts that were used by the Flatiron/Gibson system. We felt that the Weber system would be stronger and less sensitive to over-tightening than the old Flatiron/Gibson system.

Vern Brekke

[peter.coombe]

There has been a lot of debate and "advice" offered her for little progress. This is a fairly standard repair, although fairly rare in mandolins (compared to guitars), sometimes it can be caused by exposure to extremes of humidity. There is no need to remove the back, no need to reset the neck, just re-glue it. To re-glue - pull the frets, remove the fingerboard, steam the dovetail joint and remove the neck, wait for the wood to dry out from the steam, clean up the glued surfaces, re-glue the neck, reglue the fingerboard, refret and cleanup any finish damage. A shim might be needed to tighten the dovetail joint so the problem does not occur again. Not that difficult, but is time consuming so is likely to be expensive.

[multidon]

Thank you Peter. The procedure you describe is exactly what I had in mind when I said "neck reset".

But here's the thing I don't understand. You say no neck reset needed, but then you go on to describe what I think of as a neck reset. The only thing missing from your described procedure is checking the neck angle and its trueness, but wouldn't you need to do that anyway if you remove the neck? I am confused.

[peter.coombe]

Well I guess you could call it a neck reset, but I usually consider a neck reset if you need to change the angle of the neck. In this sort of situation you usually don't need to actually change the neck angle because all that is needed is to re-glue the neck dovetail joint. Of course you need to dry fit the joint and make sure the angles are still ok before gluing, and if you need to shim the joint then you really do need to make sure the neck angle is still ok before gluing it.

[HoGo]

I think by the "other" neck reset he meant change in angle of neck.
On mandolins finished with clear varnish or lacquer. But in case of modern Gibsons with rather thick chippy cloudy toned satin lacquer the finish repair will be IMO the worst part of the job and nearly impossible to hide the job.

[dhergert]

I'm no expert at lacquer, but the advertised specs of the early F9s (of which this mando seems to be an example) state specifically that they had an intentionally very thin layer of lacquer. Would that be any help in this case?

Gibson Pure headline: "Wednesday January 22nd, 2002 Sleek Gibson F-9 makes legendary mandolin sound more affordable"

"... Vintage Brown finish - a hand-stained light chocolate color with an extremely thin satin lacquer outer coat..."



-- Don

[Charles E.]

I wonder what Hank decided to do? I hope we will hear back from him.

[HoGo]

I'm no expert at lacquer, but the advertised specs of the early F9s (of which this mando seems to be an example) state specifically that they had an intentionally very thin layer of lacquer. Would that be any help in this case?

Gibson Pure headline: "Wednesday January 22nd, 2002 Sleek Gibson F-9 makes legendary mandolin sound more affordable"

"... Vintage Brown finish - a hand-stained light chocolate color with an extremely thin satin lacquer outer coat..."

-- Don

Advertisement....
Reality is diferrent. The finish on teh one I have is already chpped at the joint and the missing chip is close to 1mm thick. That is not what I would call thin finish... Also, most of the color is in the lacquer and not in the wood so it covers any imperfections around joints and edges.

[HonketyHank]

I wonder what Hank decided to do? I hope we will hear back from him.

Still pondering the alternatives. Right now I am leaning toward putting it on ebay with a relatively low starting bid, full disclosure with a link to this thread, and label it as a "project opportunity". But I am not in a hurry.

I certainly do not intend to try to sneak it onto ebay as 'just like new except for a few minor scratches and dings'. And I think I would rather get something for it than drop significant bucks into fixing it properly.