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  #16  
Old 11-27-2017, 11:00 AM
Howard Klepper Howard Klepper is offline
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Originally Posted by Shortfinger View Post
Guy 2 described a hot bend operation as a possible alternative to the neck reset.

Heat the neck to soften the glue binding the fretboard to its mahogany substrate. Then bend to straighten as required, and fixture into position until all is cooled and adhesive re-set.
This is sufficient reason not to use guy 2.
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  #17  
Old 11-27-2017, 12:27 PM
redir redir is offline
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Gosh I guess I learned on the Internet today that I suck... <<cries>>
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  #18  
Old 11-27-2017, 01:58 PM
LouieAtienza LouieAtienza is offline
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Gosh I guess I learned on the Internet today that I suck... <<cries>>
As long as you're not "guy #2," you're OK...
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  #19  
Old 11-27-2017, 02:47 PM
redir redir is offline
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Well I guess I am that guy because I have heat pressed a guitar neck in the past successfully. Well it was a bass neck to be specific. There is a jig you can make that is basically an aluminum bar with clamps to apply pressure to the neck as you heat it up. Maybe it's an old school approach but again it's not like it's unheard of.

The Thomson Belly reducer acts on a similar principal.
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  #20  
Old 11-27-2017, 05:49 PM
Todd Yates Todd Yates is offline
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Originally Posted by redir View Post
Well I guess I am that guy because I have heat pressed a guitar neck in the past successfully. Well it was a bass neck to be specific. There is a jig you can make that is basically an aluminum bar with clamps to apply pressure to the neck as you heat it up. Maybe it's an old school approach but again it's not like it's unheard of.

The Thomson Belly reducer acts on a similar principal.
A number of things are wrong with the Guy 2 answer.

First, "heat pressing" is simply the wrong fix for the Martin. The loose fitting 3/8" metal tube cold creep of the glue allows excess relief over time. Heating it and bending it back is at best temporary. It will bow again. Compression fretting is one one permanent fix, but there are others.

Second, he linked (or as stated by the OP at least) excess relief and a neck reset. Both problem affect playability, but other than that they are unrelated. I suspect Howard had that in mind when he made his comment.

The Thompson Belly reducer is a different thing entirely. It was developed for use on vintage instruments which are primarily built and repaired with hot hide glue. It does not tend to cold creep, so the fix is more permanent. It is also made correct excessive belly caused by a number of things, including abuse. Presumably the guitar will be treated better moving forward. In the OP's case, it's not poor treatment that caused the problem. The belly reducer may also be used in conjunction with re-gluing or replacing the bridge, which is a substantial brace and will also help maintain the geometry.

Regarding the bass you worked on, did it have an adjustable truss rod? If so, I'd guess you used that and heat to straighten it. The OP's Martin depends solely on the stiffness of the neck. Heat pressing does not increase stiffness, hence the temporary nature of the improvement.

Long story short, heat pressing may have some limited utility but more often than not I see repairmen suggesting it when they have no real idea how to fix the problem correctly. It's an early indicator that a different repairmen is needed - where my guitars are concerned anyway.
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  #21  
Old 11-28-2017, 06:56 PM
H165 H165 is offline
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Quote:
more permanent


Here, I include this sentence, because without it the AGF-O-MATIC sends me a message telling me my message is too short to post.
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  #22  
Old 11-28-2017, 07:17 PM
LouieAtienza LouieAtienza is offline
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Quote:
Originally Posted by Todd Yates View Post
A number of things are wrong with the Guy 2 answer.

First, "heat pressing" is simply the wrong fix for the Martin. The loose fitting 3/8" metal tube cold creep of the glue allows excess relief over time. Heating it and bending it back is at best temporary. It will bow again. Compression fretting is one one permanent fix, but there are others.

Second, he linked (or as stated by the OP at least) excess relief and a neck reset. Both problem affect playability, but other than that they are unrelated. I suspect Howard had that in mind when he made his comment.

The Thompson Belly reducer is a different thing entirely. It was developed for use on vintage instruments which are primarily built and repaired with hot hide glue. It does not tend to cold creep, so the fix is more permanent. It is also made correct excessive belly caused by a number of things, including abuse. Presumably the guitar will be treated better moving forward. In the OP's case, it's not poor treatment that caused the problem. The belly reducer may also be used in conjunction with re-gluing or replacing the bridge, which is a substantial brace and will also help maintain the geometry.

Regarding the bass you worked on, did it have an adjustable truss rod? If so, I'd guess you used that and heat to straighten it. The OP's Martin depends solely on the stiffness of the neck. Heat pressing does not increase stiffness, hence the temporary nature of the improvement.

Long story short, heat pressing may have some limited utility but more often than not I see repairmen suggesting it when they have no real idea how to fix the problem correctly. It's an early indicator that a different repairmen is needed - where my guitars are concerned anyway.
As a quickie fix for a problematic electric neck (which had a standard Fender style trussrod) I actually did use the heat technique, but afterwards popped the 2, 7, and 16 fret off, drilled some 1/16" pilot holes through the fret slots into the maple, then chopped some brads and CA glued them in and replaced the frets. A little "cheapie" fix for a certain brand neck with some "problematic" glue...
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  #23  
Old 12-05-2017, 05:24 PM
Shortfinger Shortfinger is offline
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I was all set to drive the D18 down to NE NM this week, to put it in Mr Bryan Kimsey's excellent hands, and then thought, two round trips to NM and driving ain't free, so I took it to a Martin authorized shop in Boulder.

Did I say we are moving soon, maybe by March, from this high plains front range location, RH maybe 15 percent much of the winter, to SW FL, a subtropical climate with RH well in excess of 80 percent?

So my D18 got a really good inspection by a luthier at Woodwind's and was declared borderline for neck reset, meaning that the neck relief (about .025") might be addressed first by refretting with oversized frets to expand the fret widths and take out bow.

Then there are the cracks in the top.

And the dreadful 1970 era bridge placement.

But the biggest thing is the impending move from the arid high plains to the vicinity of the Everglades, and the recommendation is I wait until the guitar becomes a Florida resident, and then see what its shape is and how to improve things.
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  #24  
Old 12-05-2017, 05:36 PM
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murrmac123 murrmac123 is offline
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Quote:
Originally Posted by Shortfinger View Post
But the biggest thing is the impending move from the arid high plains to the vicinity of the Everglades, and the recommendation is I wait until the guitar becomes a Florida resident, and then see what its shape is and how to improve things.
You could always try maintaining the guitar at a constant humidity by keeping it in its case (with a humidifier) when it's not being played, rather than exposing it to the vicissitudes of the varying ambient humidity between Colorado and Florida.
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