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Alright all (Evan?),

I got a Gibson Mk-72 in for repair and this baby is hurtin'. The finish is
pretty good and nothing is broken, but my oh my, things have warped.

First, a little background (as much as I could dig up anyway.) The Mk
series (aka the Mark series) guitars were built between '75 and '79 and
were designed for Gibson by Richard Schneider (against the better
judgement of Jeff Elliott, who didn't think it was an appropriate design for
Gibson's factory at the time.) The Mk-72 had EIR back and sides, sitka
top, EIR bridge with slide-in saddle, a plastic raised rosette, a 3 piece
laminated mahogany neck, and an Ebony/EIR/Ebony fretboard with
abalone dots.

This guitar has serial number 0021994 stamped into the back of the
peghead (I think - the second 0 isn't stamped very deeply, could be a 9),
but it doesn't match up with any of the serial number documentation I've
found. If anyone has any insight here, that would be great:


The first problem is that outside portions of the back braces on the lower
bout have come loose and buzz. Since the braces are tucked into the
linings, they can't be removed and re-glued, so is the best way to use a
syringe to glue them back down, or maybe wick in some CA? Those were
the two options I have considered so far. In any event this is the least of
this guitar's problems.

The most obvious problem is the neck. I hear Gibsons from this era were
notorious for warped necks. Well, this one has a doozie:


Jeff Elliott has told me used to do a lot of repairs on warped Gibson necks
and he would pull the frets, plane the fretboard back to where it needed
to be and re-fret. I think this one is too far gone for that.

The other big problem is the top has deformed pretty dramatically. There
is a good belly below bridge and the top has sunken above:


The result is that the action is pretty high of course and the break angle
at the saddle is very shallow.

My thoughts on this one run the gamut from 'do nothing, the guitar isn't
worth the huge amount of work to fix it', to 'great project to cut your
teeth on in terms of repairs', to 'do just enough to make it a bit better'.

So there it is. I'd love to hear thoughts and/or recommendations on this
one and I'll fill in any details I can that anyone needs. Thanks guys!

Cheers,
-Dave

Dave, don't know if you are a repair guy or just a nice guy with a friend who has "this guitar that needs some work".

If your a repair guy, I would think that you may know the value of this instrument and even if your not, by the sounds of it, you know alot about the instrument and therefore may know the general value of it. I can't see it being worth more than $1000 in good condition let alone in the condition it is in at the moment, but what do I know, not very much.

So, what is the guitar worth to the owner? Is he willing to put $300-$400 of repair into it so that it is still only worth $1000 (or what ever it really is worth). That's the real question.

What have you and the owner agreed to?

In most cases, I would tend to think like many people who do repair work would do in this situation. Think of all the time it will take you to do the repair, than double it. Than charge your repair rate at the double time. It will no doubt take longer than you think, it usually does for me anyway.

That's my $0.02 worth of suggestion. But than, I only gave it 1/2 the thought so it's really only worth a penny Rod True38993.8353935185

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Here is something that I just read on the MK series. It was designed by Michael Kasha, aka Dr. Kasha of the Kasha design. Interesting.

There are a couple of MK-35's on ebay right now ranging from $350-$900.

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

Hesh, I don't know what happened to it. The bridge plate is exceedingly
small, and it has radial Kasha style bracing, so I imagine if it lived a while
with heavy strings it would have deformed the top. The heavy strings is
just a theory mind you, as it's current owner got it in the condition it is in.
The neck... who knows.

Rod, yes it belongs to a friend, I am a nice guy , but we haven't
worked anything out yet. I am trying to figure out the options, present
them to him and work out an arrangement. I have limited repair
experienced so I wouldn't mind getting some on an instrument that isn't
that valuable.

The Mark series itself was designed by Richard Schneider who was
originally approached by Dr. Kasha to execute his bracing theories. So the
Mark series guitars are indeed what we would call 'Kasha braced', but
Gibson commissioned Schneider to design the Mark series I believe to
compete with the Ovations which had just stormed the market.

Well, My Father-in-Law and I did a re and re on a worthless seagull 12 string at in the spring of this year. The guitar was worthless as it had a ton of water damage, the top was warped really bad and there were many braces that popped off too.





Well, took the neck off, we pulled the back off, and took almost all of the original top braces off and replaced them with new braces, put in a proper xbrace and re-glued it all up in the 25' dish. Than we put the back back on and than the neck and bridge. Well, we had about 30 hours into it and it turned out really really nice. My Father-in-Law went to the kids wedding and presented him the guitar (it was his grandfather's who had died last winter). Well he was blown away. What was considered worthless by many was redeemed to show it's true worth.

If you just want to gain some experience, than go for it. Take it all apart, take lots of pictures and make lots of notes. You've got nothing to loose as long as your friend is game.Rod True38993.8845486111

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

I would say this guitar is certainly not worth the work it would need to
restore it. If it were a customer coming in to my shop I would recommend
heat pressing the neck and reglue the back braces. How is the neck angle
in relation to the current bridge position? I've never recommended a
bridge doctor before in my life, but on most of these Mark series guitars
you can't kill the tone much worse than it already is.

As to the back braces, butterfly needles are a wonderful thing. They can
be hard to find, but sometimes your local hospital may sell them to you. I
spent about 10 minutes making a plunger for the syringe (the needles are
only available in a very fine gauge and can be hard to force glue through),
and keep it in a glass of water when not using it. Then I soldered an
alligator clip to a chunk of solid 10awg electrical wire, and use this tool
all the time. If you don't want to go through all this trouble just work glue
in with your finger and a feeler gauge and clean it up when you're done.








David Collins38993.9319791667

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Eschew obfuscation, espouse elucidation.

and before you try to work any glue under the brace scrape out as much of the old glue as you can.

Dave,
I have done repairs similar to this. I don't know what you feel the repairs are worth ( to you as well as the customer). I always think one amount and then do it/say for much less. Then as I do the work I say to myself "never again...never will I do this so cheaply..." . Until the next time...

I estimate closer to over $1000. in repair work. As stated above, the neck isn't just warped...it's twisted. That means fretboard removal, shavng the neck ( if possible) true, new fret board ( old one will probably shrink when removed and remain somewhat "twisted"). New fret job. Probably a neck re-set to help compensate the action problem. Probably still need a bridge doctor to aleviate some of the bow in the top and you still have those loose braces.

Now, if you'r not "in the biz" and this is a hobby for you, then it might be a lot of fun...certainly a great learning experience. On the other hand...what is 10-20 hrs of your time worth?

You need to talk to the customer and find out the "real" value of the instrument. I recently repaired a few "sentimental value" acoustics and the owners could care less about the cost to repair/restore. To them, the real value was in owning and playing an instrument once enjoyed by a deceased loved one.Dave-SKG38994.4399768518

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Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"

David Collins,

I love that glue jig...neat!

_________________
Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"

Izzat a "2" I see stamped between the second and fifth tuners? Many if
not most of the Marks I've had in the shop were stamped as seconds that
way. In fact, Gibson made a huge number of seconds in that ill-fated
Mark series.

They also had a designation "BGN" for those they felt couldn't make it to
the exalted "second" classification. I find it helpful to explain the
miserable state of Gibson's production to owners of Mark series guitar so
they don't get the mistaken idea that they are in possession of a desirable
or collectible instrument.

Some have survived in fine condition, of course, and have owners who
like the way they sound and play. But, I find it interesting that this is the
kind of instrument that turns up for sale on the Net with lots of
superlatives and the word "rare" in the description, while truly rare and
great guitars need no such hype and are more commonly listed simply by
their names. . .

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Cheers,

Frank Ford

FRETS.COM
HomeShopTech
FRETS.NET

I second the recommendation to do a heat-set repair on the neck. I repaired a very similar twisted neck and it came quite good. This is a lot quicker that removing frets and planing flat.

Thanks all!

David, I love the butterfly needle setup! I'll have to get something like that
set up whether I use it on this guitar or not.

Frank, no that's just a smudge not a 2. Can't find any other markings on
back of the peghead, so this seems to be el primo Mk-72. Does that
change your mind on the collectability rating for this one?

Barry, what was your process for doing a "heat-set" repair on the neck?

Does anyone know what the neck attachment method was on these
guitars? I assume it's dovetailed, but with Schneider it could have been
anything.

Still pondering this one... keep the thoughts coming guys. I really
appreciate it.

Cheers,
-Dave
dgalas38994.5748726852

BTW, if anyone cares, here's what Mr. Cumpiano had to say about the
Mark series:

Regardless of what Schneider later called (in conversations with me) the
impulsive and premature decision to misapply the system, Schneider
indeed participated closely in the design, tooling, production and
marketing of the Gibson Mark steel-string guitar. The process was vastly
more complex and difficult than the production of ordinary guitars. The
result was a utter, certifiable and expensive flop. The Gibson Mark guitar
was heavy, ugly and an utter failure sonically. It also suffered from the
worse aspects of mass-produced guitars: bad glue-ups, poor materials
selection, indifferent workmanship, bad action adjustments...in short, a
complete fiasco.

Ouch!

Well, I'm leaning toward removing the neck and the back and fixing
everything just for the experience. Can anyone confirm for me that the neck
is dovetailed on these guitars? Steaming it off is the way to go I presume.

Cheers,
-Dave

[QUOTE=dgalas] BTW, if anyone cares, here's what Mr. Cumpiano had to say about the
Mark series:

...in short, a
complete fiasco.

Ouch! [/QUOTE]

C'mon, Mr. Cumpiano, tell us what you really think!

I'd offer to buy it cor cheap, then dive in, with the stipulation that if it's successful, he can buy it back with the cost of repairs added. If it's not a success then you've learned a lot.

I think the real value in a project like this is what it can teach us about what wood feels like when it's at its limits of stress as you're trying to force a top or a neck back into shape. Building usually can't teach about what it feels like to try clamp a twisted neck to make it straight, how far you can bend top wood before you hear the tell-tale clicking that means it's about to start cracking, etc. At least, we hope that we don't have to deal with such issues during a build! I gained a lot of touchy-feely kind of sense about instrument woods while repairing and rebuilding junk guitars, not to mention what they look like (or perhaps shouldn't look like) inside. I think I owe a lot of my "victories" to having put all those junkers back together. One of them I still have, but alas, it's not the L-00 I gave away! burbank38996.8007638889

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now known around here as Pat Foster
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I wouldn't remove the neck unless it is in need of a neck set to fix a
high action.

Removing the twist is actually easier with the neck attached to the
body, assuming your doing a heatset. The reason for this is that the
body gives you a way to control the neck when trying to untwist it.

My setup for the heatset can be seen in the photo. I had the guitar
clamped in my string compensation jig which was basically used to
hold the body firm. You could probably rig up a way to clamp your
guitar to your workbench. I bolted a 1x4 to the peghead to give me
a "handle" for untwisting the neck. I used a 2"x18" heating blanket
on top the fretboard which was held down with a 2x4 and the clamp.
I heated the neck up until I felt warmth on the back of the neck.
Then I propped a board under one end of the 1x4 to twist the neck
back a little further than straigth. I turned the heating blanket off
and let her cool for 24 hours. When I took the setup apart, I was
pleased to see the neck came out perfect. I kind of got lucky on this
one.

Thanks Barry,

I might give that a shot. Depending on how the top comes out the neck may
have to be reset anyway, so I was thinking of just replacing it. Since this is a
learning experience, I might go for the de-twist then re-evaluate.

Thanks again for the info.

-Dave

   So many options on this disaster. You should find that like many I use heat to straighten things out. A good set of heat blankets will do well but you can also use the old Kitchen oven or cloths iron.
    The important thing is to heat the glue to let it creep then hold the joint in the position it needs to be in. On black bracing I like the jig . Rememeber that only hide glue can stick to itself all other glues need a good cleaning . Warm water helps and be sure to allow ample drynig time.
    This is a project that will test your skills and You and the customer should be clear and agreeable. I do like the suggestion about buying it and then allowing the customer to buy it back.
    You have alot of work here but you will surely learn alot.
Good luck and keep us posted. I think there are allmost as many techniques in repair as there are repair people
john hall
BCG

A book called, I think, the History of the Guitar, from Renaissance to Rock, has a good pictorial of the construction of the Mark Series Guitars and will likely show the neck joint. If you can't find the book let me know and I will look at mine for you and see what I can help out with.

Shane

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Canada

Thanks Shane,

Do you know who wrote it?

It's at home Dave but I am not. I will look tonight and let you know.

Shane

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Canada

Thanks Shane,

Whenever you get to it.

Hi Dave,

The book is "Guitars - From the Renaissance to Rock" by Tom and Mary Anne Evans, 1977 - ISBN # 0-448-22240 X.

On page 279 it shows the Mark neck joint as a tradition dovetail joint vertically but with a mortice into the top and head block for a tenon on the fingerboard extension. This mortice looks about 1.5 inches wide and about 2 inches long by about .5 inches deep. There is a hole in the mortice on the guitar so I don't know if this extension is bolted down or glued. You know, why not e-mail or call Gibson and ask what they have to say about this joint? They may have the solutions for you! In any event, this a GREAT book and well worth hunting down!

Shane

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Canada

Thanks Shane, I'm on it!!!