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PostPosted: Sun Nov 01, 2015 5:06 pm 
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Walnut
Walnut

Joined: Thu Oct 29, 2015 3:59 pm
Posts: 2
Hi,

In the mid 80’s I bought a used Gibson MK35 and over the years played the heck out of it. Along the way, the MK accumulated “personality”. It was loaned, used, glued, abused, dropped and well-traveled. Even with all this, I could always throw a new set of strings on it and it played nicely and sounded good to my ears. Within the last year, the top started to deform where the bridge is attached rendering the guitar unplayable.

My interest in guitar design was never beyond using it as a tool (until recently). A decision was made to sell the MK, however, I changed my mind and plan to give the repairs a go. That’s why I’m here. On the way are a few books that I hope to be of help in addition to expert advice on this forum.

If you good folks are up to offering a few suggestions as I fumble along, I’ll be indebted. I surely don’t want to give the impression that anyone can come along and slap a guitar together. I admire the skills, knowledge and experience you guys have. When completed, if the MK can accept strings and play a decent chord, I’ll be overjoyed.

If the consensus is positive I’ll post up details of this unique MK35 and continue on as a “repair” thread.

Thanks,
bel



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PostPosted: Sun Nov 01, 2015 7:37 pm 
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Contributing Member
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Joined: Sun Mar 06, 2011 12:04 am
Posts: 5824
First name: Chris
Last Name: Pile
City: Wichita
State: Kansas
Country: Good old US of A
Focus: Repair
Status: Professional
The MK series was not one of Gibson's success stories, but if this is one is good - it can be saved. Have you done a search here to find threads about removing and reglueing the bridge?

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"Act your age, not your shoe size" - Prince


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PostPosted: Mon Nov 02, 2015 7:49 am 
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Old Growth Brazilian Rosewood
Old Growth Brazilian Rosewood
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Joined: Fri Nov 02, 2007 9:49 am
Posts: 13387
Location: Ann Arbor, Michigan
First name: Hesh
Last Name: Breakstone
City: Ann Arbor
State: Michigan
Country: United States
Status: Professional
Hi Bel and welcome to the forum. As Chris rightly said the MK series was not G*bson's finest hour and was the result of a collaboration with Kasha and one other, Richard Schneider. They were considered state of the art in their day and there were a number of innovations introduced with the MKs.

One of my friends has one that his Dad gave him for high school gradation and we have also worked on a number of others.

Yours likely needs a neck reset and if the top is distorting there is likely a reason such as the bridge plate has worn from the string balls trying to pull up through the holes since these used cheap, plastic, moulded bridge pins. This can crease the plate making for an unstable surface for the bridge and then the bridge lifts. Braces can be loose too.

I can see in your pics from here the deformation of the upper bout just next to the neck, that often means neck reset and the guitar is old enough that it will need a reset likely too.

When we see and work on these it's not unusual for them to need what we call the "whole nine yards" and this level of work can often be over $1K to have done commercially AND............ well.

Neck resets are not the place to learn to work on your own instrument especially if you have high hopes that the instrument will be made right and like new in terms of playability. Bridge plate repairs and replacement are also not a hobbyist type of DYI repair and there is risk of splitting the top center seam if done incorrectly.

For neck resets you need to know and understand acoustic guitar geometry and have some pretty good finishing and wood working chops too.

With this said step one would be to measure the action for the high e and the low e at the 12th fret measured in 64th of an inch and let us know what it is? This will be how we determine if this thing needs a reset.

Most of all though my suggestion to you is if you value the instrument like my friend values his complete with college bong water stains and all...:) please consider getting an eBay beater to learn repair work on and put this one aside until you can do the things such as a neck reset, bridge removal and reglue, bridge plate repair, etc. well and reliably. People do like the MKs and they have a loyal following as you can see on the Internet.

Lastly you will also need some special tools that you likely do not have as well and I am telling you this so that you have hopefully a realistic view of what you are in for if you go the DYI route.

If there is any hint of FUD, fear, uncertainty, and doubt in my post as a stalking horse to scaring you out of the DYI route and into sending it to our professional repair business relax, we don't accept shipped in work and have more than enough work to keep us happy.

My interest is two fold with the well being of the instrument coming first (sorry...) and giving you quality information and advice next.

Again welcome!


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PostPosted: Mon Nov 02, 2015 8:34 pm 
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Walnut
Walnut

Joined: Thu Oct 29, 2015 3:59 pm
Posts: 2
Hi guys,

Thanks for the interest and honesty. I understand that the MK series is not thought of highly by some folks. My MK always played nicely and sounded good to me.

I already took the strings and hardware off. String height at the 12th fret was close to 3/8” from memory (see the warped-top photo below).

Decades ago, the neck was glued after physically coming loose from the body. When I received the guitar after the repair, the strings were not centered on the fretboard. The high e was too close to the edge and the low E was too far away. I always attributed the string misalignment to the neck and lived with it. Yesterday, I routed a strong thread through the nut high and low E slots, down the fretboard over the bridge and secured the ends at the longitudinal center (lower body). I assume the bridge should align with the guitar center between the D and G string holes. It actually sits about 5/32” off center towards the high E string. This was the cause of the off-center strings.

This MK has what looks to be a J45 top and bridge. The bracing is real close to production Kasha bracing.

I don’t plan to do anything soon and will consider your advice.

Thanks,
bel


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PostPosted: Tue Nov 03, 2015 7:39 am 
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Old Growth Brazilian Rosewood
Old Growth Brazilian Rosewood
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Joined: Fri Nov 02, 2007 9:49 am
Posts: 13387
Location: Ann Arbor, Michigan
First name: Hesh
Last Name: Breakstone
City: Ann Arbor
State: Michigan
Country: United States
Status: Professional
Hey Bel thanks for the measurement. 3/8th" is 24/64th" at the 12. The target spec for the low e at the 12th for this guitar is around 6/64th" so the thing needs a neck reset as I suspected.

You can also see that neck resets are pretty difficult for folks who have never done any Lutherie work before because whom ever did the one on your MK really screwed it up if they can't even follow and work to a center line resulting in the high e being too close to the edge of the fret board.... This is yet another reason why the neck likely needs to be reset to recenter it as well.

Since it has been reset and since it's a dovetail it's also likely that the previous neck resetter may have done something to make it even more difficult to get off such as too much glue gluing the neck cheeks to the sides or no telling who's lunch is in there as a shim...

You may be in for some struggles with this one.


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PostPosted: Tue Nov 03, 2015 7:41 am 
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Old Growth Brazilian Rosewood
Old Growth Brazilian Rosewood
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Joined: Fri Nov 02, 2007 9:49 am
Posts: 13387
Location: Ann Arbor, Michigan
First name: Hesh
Last Name: Breakstone
City: Ann Arbor
State: Michigan
Country: United States
Status: Professional
Also some more Lutherie forensics for you. The bridge shows string ramps that were likely made after production and as a quick fix for the neck angle being ready for a reset.


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