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Neck Removal on 1931 Martin 0-18T Guitar: Restoration and Repair, Pt. 2

Before we take the neck off the 0-18T for the reset, we need two more important measurements. You may recall we already measured the distance a straightedge laid on the frets falls below the bridge.

The next measurement we need is the height of the neck heel. You can see me capturing that measurement here.

And we also need the distance from the center of the saddle to the body/neck joint.

With those numbers in hand, we can calculate how much material needs to come off the bottom of the heel to tilt the neck back for the correct angle.

If you can read the maths I did on the left (click and it's larger...), or you can find the formula elsewhere.

Now we know we need to remove .040 of an inch to have the correct angle.

Now we can remove the neck.

We're going to drill into the dovetail joint and inject steam to loosen the glue so the neck can be removed.

First step is to remove the fret that is above the dovetail. In this case, it's the 15th fret. We heat it up a bit with a soldering iron.

And use fret pullers to pull the fret out.

The now nekkid fret slot.

This guitar was made in 1931. Martin didn't start using T-frets until about 1934. My other 1931 model has bar frets, but this one has T-frets.

I suspect that these are not the original frets. But whoever did the refretting did a great job.

The fingerboard extension has to be unglued from the top.

I have a homebrew body protector - foil over cardboard - that I use to protect the body from heat during this process.

This guitar's fingerboard is a bit narrower than my template's opening, so I put some extra foil on the shoulders of the guitar.

Heat the fingerboard extension with my trusty fingerboard extension heater.

There's foil over the extension itself so the wood won't scorch. And notice that I also heat my removal knife under the iron.

I usually heat the extension with the iron on its highest setting, applied to the wood (foil) for a minute at a time.

Then I'm able to gradually slide the removal spatula into the joint.

The old glue is hide glue, which separates pretty easily with heat.

Take your time and don't force the knife. When you have resistance, put all of the foil back on and heat the joint some more.

Eventually the extension will be freed up from the top of the guitar.

I just saw a Dan Erlewine video where he separates a whole fingerboard using this method - and he used two knives - one on top of the other to help protect the wood. I'll try that next time.

Next we drill our steam access hole through that slot where we removed the fret.

I have a long (6 inch I think) thin drill bit for this job. Be sure to put a flag on the bit so you don't go too deep!

The idea is to hit the side of the dovetail. It's always a bit of a guess unless it's the same type of instrument you've done before and know exactly where the side of the dovetail is.

I was a bit too far toward the center on this one as it turned out. But the joint still came apart ok.

Now we heat up our steamer. This is a Krups espresso machine I bought used on Craigslist for $10. Works like a champ.

You can see the steamer hose attached to the machine on the left side.

I also have my trusty homebrew neck removal jig. Basically it holds the body in place. There is a screw in the center that goes under the neck heel.

We apply steam and crank the screw handle a tiny bit...tiny bit...until the neck releases.

In practice, I've found that the neck can be jiggled side to side as the steam loosens the glue. Sometimes that motion is enough to release the neck.

Now we can apply steam via the hole we drilled into the joint.

There is a bit of water along with the steam, so I have clean rags there to catch it.

I usually apply the steam for maybe 15 seconds at a time and test the joint. It will take a few minutes to get the joint loose.

Don't force it! Depending on the guitar, there could be a lot of glue in the joint (e.g. Guilds). Usually Martins pop right off, but this one took a bit longer than usual.

And here's the removed neck.

It does seem as though this guitar had a bit more glue than usual in the joint.

I like to scrape the old glue off both parts of the dovetail while it's still warm, since it will come right off.

You can hit the dovetail with a touch more steam if needed.

See the white mark in the finish? This is not unusual when you steam the neck off.

It's actually finish 'blush.' Moisture is trapped under the lacquer.

Do not panic if you see this! It's easily corrected.

Wipe a small amount of denatured alcohol onto the affected area.

The alcohol will soften the lacquer and release the moisture. The finish will look a little flat afterward.

Let it harden for a couple of days and then it can be polished. It will look perfect afterwards.

Now we can go about trimming the neck heel for the actual reset.

All posts in the 1931 Martin 0-18T Restoration Project:
  1. 1931 Martin 0-18T Guitar Restoration and Repair, Pt. 1

  2. Neck Removal on 1931 Martin 0-18T Guitar: Restoration and Repair, Pt. 2 - This page.

  3. Trimming the Neck Heel for Reset: 1931 Martin 0-18T Restoration and Repair, Pt. 3

  4. Shimming Guitar Neck Dovetail and Finish Chip Repair: 1931 Martin 0-18T Restoration and Repair, Pt. 4

  5. Caul for Heat-straightening Guitar Neck: 1931 Martin 0-18T Restoration and Repair, Pt. 5

  6. Reparing Acoustic Body Cracks: 1931 Martin 0-18T Restoration and Repair, Pt. 6

  7. Making a Tortoloid Pickguard: 1931 Martin 0-18T Restoration and Repair, Pt. 7

  8. Heat Straightening Bowed Guitar Neck: 1931 Martin 0-18T Restoration and Repair, Pt. 8

  9. Fret Marker Installation and Filling Fingerboard Chips: 1931 Martin 0-18T Restoration and Repair, Pt. 9

  10. Compression Fretting to Correct Upbow: 1931 Martin 0-18T Restoration and Repair, Pt. 10

  11. Completed 1931 Martin 0-18T: Restoration and Repair, Pt. 11


Post a Comment 2 comments:

  • Sven Nyström said...
    October 28, 2016 at 7:49 AM
    Nice work. Have you considered removing the entire fretboard to install a carbon fibre rod into the neck? I did that on my Dobro tenor from 1936, and so far I haven't thought a neck reset is necessary now the neck is straight.
  • Yr Fthfl Blggr said...
    October 31, 2016 at 8:10 PM
    Thanks for the kind words.

    I remember your post about the rod and I think it's a good idea. But on this guitar, the fingerboard has splits or something along the sides, so I don't want to try to remove it. I write more about it in the Pt. 3 post.

    BUT I do have some other guitars in the works that I'm going to put rods in for sure.

    You know Stew-Mac has titanium rods now? Crazy.

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