I need advice on restoration of a severly damaged Martin D28 that I acquired - Page 2

Jimhar · #16 10-24-2021, 06:42 AM

printer2 · #17 10-24-2021, 07:08 AM

The best I could do with the post.

Jimhar · #18 10-24-2021, 07:34 AM

Thanks Fred for the help. I just pasted the link in the image upload and it would not post till you did your magic. What did I do wrong?

mirwa · #19 10-24-2021, 07:43 AM

I dont understand why you would decide to try and resurrect and re-install this top if the guitar has already had a new top fitted, it will not add value to the guitar in any form.

This is coming from someone that speciliazes in difficult repairs

Steve

Jimhar · #20 10-24-2021, 10:43 AM

Quote:

Originally Posted by mirwa

I dont understand why you would decide to try and resurrect and re-install this top if the guitar has already had a new top fitted, it will not add value to the guitar in any form.

This is coming from someone that speciliazes in difficult repairs

Steve

This situation with this Martin guitar is about as mixed up as it could possibly be. The new top that was fitted to this guitar had so many issues of cracks in the new top and separation of the plates and failed cleats on that separated joint and improper rosette installed left me with a real bad feeling about the work that had been performed on the guitar and led me to remove it and here wew are. the new top came off quite easily as did the binding and purfling. They practically fell off .
The situation with the guitar financially is that I have virtually nothing invested in the guitar. It was thrown in as just another box of guitar stuff that I purchased from this lady selling her late husbands stuff which she had no further use for. All of the material other than the guitar was worth well more than the price I paid for it which put the guitar price at free!
Now with that being said What you specialize in is what I need some advise on. I have seen your replies in other posts that lead me to know you are someone of knowledge that would have great insight into problems such as this. I do feel that this would qualify as a difficult repair but not an impossible one but you may differ in your opinion of that. If I do proceed with the repair of this top it is not for purposes of preserving value or profiting but I amsimply trying to make the instrument whole again and if possible with the tattered original top. I may find that the top does not sound good enough after the repair is done to have warranted the effort at which time I may decide to just remove it and install another new top on the guitar.
This isn't about enhancing the value in order to sell the guitar for a profit as I intend to keep it. I would like to have the original top on the guitar if feasible but I know that it will require a difficult repair and I hope to learn a lot in this undertaking. I hope what I have said makes sense and you will find this project worth some comentary. Thanks for your interest.

mirwa · #21 10-24-2021, 06:01 PM

Unless it holds some historical value, I would personally not waste my time trying to resurrect that top, yes it can be done, but for 40 dolars and 15 minutes of work you will have a new top ready to be fitted way more structurally solid and presents better on the finished product

Steev

Jimhar · #22 10-24-2021, 07:07 PM

Quote:

Originally Posted by mirwa

Unless it holds some historical value, I would personally not waste my time trying to resurrect that top, yes it can be done, but for 40 dolars and 15 minutes of work you will have a new top ready to be fitted way more structurally solid and presents better on the finished product

Steev

Just for the sake of arguement lets say you had a good reason to attempt such a repair as this. How would you proceed to acheive a best outcome using this top?

mirwa · #23 10-25-2021, 02:45 AM

Start with gluing and cleating all the open and visible cracks.

Graft fresh wood into the bridge patch

Make a fill piece for the fretboard extension area

Restore and repair the rosette and surrounding wood

Jimhar · #24 10-25-2021, 01:57 PM

Anyone have any preferances as to what is the best glue to use on crack repair on tops and braces and cleats? Some seem to recomend tightbond and others hide glue but still someothers say CA and then there is fish glue. I dont seem to have a personal preferance from experience and would like to hear some opinions from you guys. I have more experience with tightbond than anything else but that was not on guitar tops. Thanks

redir · #25 10-25-2021, 06:53 PM

Quote:

Originally Posted by Jimhar

Anyone have any preferances as to what is the best glue to use on crack repair on tops and braces and cleats? Some seem to recomend tightbond and others hide glue but still someothers say CA and then there is fish glue. I dont seem to have a personal preferance from experience and would like to hear some opinions from you guys. I have more experience with tightbond than anything else but that was not on guitar tops. Thanks

If you are already using Titebond then just use that. It's pretty much the default glue for guitar construction and many other instruments. It's great stuff. Easy to use and cleans up really well. It's also very strong and has enough years behind it to be well trusted.

CA is almost never recommended on top wood as it can terribly stain the wood. Fish is also very easy to use and strong, also a good choice. Hide glue is the best choice for many luthiers but it requires a bit of a learning curve to get right and so without you first learning how to use it would not recommend it.

You can't go wrong with Titebond IMHO.

Jimhar · #26 10-25-2021, 07:35 PM

well that sounds good to me. Tightbond it is for this project. I was considering HHG but some of these clamp ups are going to be more than just slamming a clamp or two on as you know. It's difficult enough to keep an unbraced top in a plane with clamping pressure on it while it cures enough to be self supporting and I'm not that experienced at setting up these clamping schemes with the hide glue timeclock ticking. Thanks for your advice on this. Much appreciated. Jim

phavriluk · #27 10-26-2021, 07:09 AM

Titebond Original sets up pretty quickly. Titebond Extend takes longer, allowing for more time to adjust clamps.

Jimhar · #28 10-26-2021, 11:41 AM

Quote:

Originally Posted by phavriluk

Titebond Original sets up pretty quickly. Titebond Extend takes longer, allowing for more time to adjust clamps.

I was not familar with the Toghtbond Extend formulation.That should prove to be useful as some of these clampups will be a bit complicated. Thanks a lot for the info. Jim

redir · #29 10-26-2021, 02:08 PM

You can also dilute Titebond original up to 10% to extend it and it will not lose strength. Fish glue is the best for open work time.

If the cracks come easily together than you could use a strong tape to apply clamping pressure for gluing the cracks together. It's always better though IMHO to use more clamping pressure than tape can apply though.

To do that, since its a cut to shape guitar top with it's curves though you need to get a bit more clever. Use the top as a pattern and draw it out on a piece of 1x wood or some such thing. It doesn't have to be the entire length of the top from head to toe. Just enough to cover the lengths of the cracks you are fixing.

Then put everything out on a flat table. Clamp one side caul to the table, glue up the crack and place it to fit to the contoured caul (protect the table from squeeze out with newspaper or something) then with a long board of MDF or something like that, again line with newspaper, put that on top of the crack and lightly clamp in place. Place the other contoured caul on the other side then with long bar clamps squeeze everything together as you tighten the flattening caul.

I know that's hard to understand in words. So in the image below there are two straight cauls left and right of the top being glued up. Those would obviously have to be curved to fit your guitar top. Then you see the long flat cauls to hold the two halves down so that when pressure is applied the halves come together perfectly. I am using wedges for clamping pressure instead of long bar clamps which you could also do if you make another flat long caul behind the curved one and wedge it from there.

I hope this makes sense.

Jimhar · #30 10-26-2021, 08:17 PM

Quote:

Originally Posted by redir

You can also dilute Titebond original up to 10% to extend it and it will not lose strength. Fish glue is the best for open work time.

If the cracks come easily together than you could use a strong tape to apply clamping pressure for gluing the cracks together. It's always better though IMHO to use more clamping pressure than tape can apply though.

To do that, since its a cut to shape guitar top with it's curves though you need to get a bit more clever. Use the top as a pattern and draw it out on a piece of 1x wood or some such thing. It doesn't have to be the entire length of the top from head to toe. Just enough to cover the lengths of the cracks you are fixing.

Then put everything out on a flat table. Clamp one side caul to the table, glue up the crack and place it to fit to the contoured caul (protect the table from squeeze out with newspaper or something) then with a long board of MDF or something like that, again line with newspaper, put that on top of the crack and lightly clamp in place. Place the other contoured caul on the other side then with long bar clamps squeeze everything together as you tighten the flattening caul.

I know that's hard to understand in words. So in the image below there are two straight cauls left and right of the top being glued up. Those would obviously have to be curved to fit your guitar top. Then you see the long flat cauls to hold the two halves down so that when pressure is applied the halves come together perfectly. I am using wedges for clamping pressure instead of long bar clamps which you could also do if you make another flat long caul behind the curved one and wedge it from there.

I hope this makes sense.

This idea you have to set up the clamps and hold everything together both
down and with side pressure at the same time is exactly what I have been working toward but had not quite got all the ideas together yet. This is a great help. I was thinking of incorperating some plexiglass on top so i could see when I had enough pressure to close up the crack or cracks. I was unsure whether to do more than one crack at the time. I think with the long crack from the tail block through the bridge hole location and then through the sound hole which now has the top in two separate halves with the top of the sound hole being destroyed and missing the piece of top under the fretboard extension as well. This is making me wonder if I should have this piece already fabed and ready to clamp in at the same time as I am doinng the glue up of these long cracks. I do not have a clear defined plan at this point as to what I should do first and second or both together. Should I try to piece the soundhole back together and join that part back to the fret board extension piece that I am yet to fabricate. As an alternative I have thought of building a piece to fit the missing part at the top and incorperate with that a total new sound hole and rosette. It all has to come together and that could happen at the front of the bridge hole with a new bridge plate a bit larger in front of the bridge and behind the bridge to help mate the patch in the hole under the bridge. That would connect the two top halves securely back together. I was also thinking of adding a circular reinforcement under the new rosette restoration to join it to a new piece of sitka above the soundhole. I still have not solidified a plan that I want to go with for sure but I think its in there somewhere! What do you think? I know that I also could just put a new top on it and the I would miss all the fun of trying to learn how to make all the cracks and dings disapear with some finishing wizardry.

I really appreciate your time and effort to point me in the right direction here. It helps a lot to hear what an experienced luthier would do in this situation.

Jim