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RESTORATION - 1934 000-18

 

This guitar was referred to us by our friend Frank Ford.  As you will see, it was in need of a lot of work.  The most obvious problem was that most of the X brace was missing.  You will see the other issues in the photos.

    Neck is out - the first step.

   another view.

  and another

   The bridge has to come off (even tho it is not coming off) so that we have a "flat" top to glue to.

  Whenever a bridge is removed a few splinters of the top come with it.  These are carefully removed from the bridge and glued back onto the top.  For a guitar of this vintage we use hot hide glue - since that is the glue used when it was built and because it is a wonderful glue. 

  There was a small section of the top under the fingerboard extension which was loose - essentially there was a crack.  Ron is using the light to warm up the wood prior to gluing it.  Hide glue has a VERY short open time (about 60 seconds) which can be extended if the wood is warm before applying the glue.  Of course one does have to be cautious.

   Here the loose piece of the top is glued and clamped.  We have mapped the top to get the angle of the X brace ( we want to pre-make this before removing the back.    The next step will be to remove the back.  that will be a interesting bit of work.

  Removing the binding on the back - in preparation to removing the back.  A slow and tedious process

  More of the same.

  and more

  etc.

  etc.

Now to remove the back.  It may seem strange to consider removing the back  but subsequent photos will demonstrate why.

  More of the same.  Another slow and tedious process.

  Back is loose from the neck block

and it is OFF!!

Here is the problem.  Much of the X brace is missing.  The X brace will have to be completely removed and replaced.  Plus that strange bit of rosewood.  And the bridge plate is cracked too.

  Close ups

  close ups

  and more

   This is the neck block

  The back

 

  Here we have filled the small slot in front of the bridge.  We opted to remove as little of the original top as possible so the edges of the slot (and the new wood) are not perfectly clean.  However any cross grain repair like this will be very visible so the intent is to fill the slot with good wood (and hide glue) and still get a good joint.  If I had taken a photo of this slot before we filled it you would see that the edges were beveled (as was the "new" wood we added.  this gave us a reasonable amount of gluing surface.

  This is the jig we made to guide the router for cutting the "hole" for the patch we need to put in.  The jig is held in place with screws placed strategically through bridge pin holes and the soundhole, so that it is held rigidly in place without making any marks in the top.

This is the router bit - it has a ball bearing on top of the cutter that rides along the sides of the jig.

Router on the jig,

A bit of holding the breath while Ron cuts the "hole".

Which then looks like this.

We have made a patch of Adirondack spruce (which is the type used by Martin at this era) which fits exactly and even has a good grain match.

After warming the surfaces and applying hide glue, the patch is glued in.

another view of this.

the patch is in.

One reason we elected to route out the cavity for this patch rather than feather the wood into a curved edge is that all of the edges of this patch are under braces - either the X brace or the bridge plate.  This will give extra reinforcement to the edges of the patch.  It is very easy to get a good wood to wood gluing surface when routing the cavity.

  Starting work on the X brace

This shows the notches which permit the braces to join properly.

the ends have been cut to length and thinned down to fit under the lining.  The lining at the back has been removed to permit the brace to drop in but has been saved and will be put back into place.

  Another view.  Before the brace is glued in (one leg at a time) it will be shaped to match the size and shape of the original X brace.  the braces which do remain will help us a lot in doing this - the old braces were measured but were so far gone that they were not as much help as one would like. 

  The first leg is placed to ensure fit.  A few dry runs will be done before gluing since hot hide glue has an "open time" of about 90 seconds.  Gotta work fast.

  Here the clamps are in place.

  The other leg is in place and clamped.

  Another view.

  One of the small "finger braces" was missing so we will replace it.  Nice to have the other 3 for a model of size and shape.

  That's glued in too.

  Here is where the kerfed lining was removed so that we could get the X brace in.

The "missing" piece of kerfing is now glued back in place.

   Making and fitting the new bridge plate - this was made to be exactly the same thickness as the original.

  Glued back in place.

Gluing the back in place.  This has to be done a small section at a time due to the quick setup time of the glue and the desire to make the back fit EXACTLY as it was originally

  Guitar repair shops accumulate lots of clamps.

 

  More of the same

 

  More

  Gluing the binding back in place. 

 The 3M sensitive surface masking tape is good because it is much less likely to interact with the old finish.  

 

  The binding was put back so closely that no touch up finish was necessary. 

 

This website and all of its content, text and images are copyright 1997-2012  by Charles A. Hoffman.  All rights reserved.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2219 East Franklin Ave.
Minneapolis, MN. 55404

hoffmanguitars@qwestoffice.net  or choffman820@comcast.net

(612) 338-1079