Mike's Oud Forums

Used fretboard how to fix?

Yaron Naor - 9-21-2009 at 07:56 PM

My friend, an Oud player, (play a lot) have a problem:
After a year we saw that the fretboard has long holes beneeth the strings - see the photo
Does anyone know if there any solution how to fill it with some material, or glue?
(The fretboard is too thin already to sand it down)

[file]11293[/file]

fernandraynaud - 9-21-2009 at 10:14 PM

Well, this looks like a good quality rosewood, but that's what I've always thought, that any fretless instrument should have the fingerboard sealed immediately, BEFORE problems develop.

For what it's worth, for people who have not yet reached this stage, so far the most practical protective coating I've found for my needs is Tung Oil, and I'm mentioning it again because it's been very useful. It's surprisingly hard after it sets, easy to build up in thin layers, very easy to correct wear and rebuild the coating every few months if needed, like whenever you change strings, it only takes the instrument out of service for about 24 hours, new coats bond to the old. I have fretless basses that have like-new fingerboards. You have to stay on it, check your fingerboard regularly and never neglect it. But it's not a good filler if the wear is already severe like you show. It's also a little strange to work with, make sure you wear gloves, it goes from viscous liquid to hard polymer in some steps, and it's difficult to get it off your skin if you contact it while it's still very tacky. Japan Dryer can be used to speed setting -- formulas like Formsby's already have it in the mix. There are lots of advantages, like the fact it's liquid to start with, and does not alter the tone as much as epoxy. Normally the first layer soaks into the wood, but I was amazed to find that with a little sanding, it will even bond to a varnished fingerboard without requiring totally stripping the old finish. Here is a fingerboard with thin layers of Tung Oil, as you can see it's much too thin to act as a filler.

[file]11295[/file]

Incidentally, what are we looking at in your photo? Is the fingerboard removed from the instrument?

There are two other techniques people use that might help here. One is indeed epoxy. You might look up some articles and videos on using epoxy for fretless bass fingerboards. It's a bit tricky to work with, but it's tough and a good filler.

Another, and I think that might work for this fingerboard, is gel cyanoacrylate, gel SuperGlue. What I've seen done is sanding the surface lightly, then gooping on some thin layers of gel superglue with e.g. a playing card, using accelerator to help it set, then another layer, then sanding perfectly level with a long sanding block, then steel wool. By the time you are done it's a hard transparent glassy surface. It will brighten the tone, so maybe you'd prefer a little rougher texture. The stuff is not quite as tough as certain epoxies, but it's fast setting and pretty easy to work with. Obviously gloves are important to wear. I can't find the articles at the moment, but there are some very good ones on using it for fretless basses as a protective layer, the gel kind should also work reasonably OK as a filler, I must admit I've never tried it myself, but it seems plausible. You obviously need to start with a lightly sanded and clean surface. How deep a layer you can use for filler would have to be determined by trial and error. It's also possible to apply more if it wears after a while, though not as easily as Tung Oil. But you need something that can act as a filler here, and Tung oil will not set easily as filler, so Epoxy or Gel Cyanoacrylate is what I'd try on this fingerboard.

Varnishes and lacquers and shellacs and urethane are pretty useless. They are too soft and offer no advantages.

Good luck!



freya - 9-23-2009 at 01:41 PM

I have filled several worn oud fingerboards with good success. First I score the fingerboard with a sharp x-acto along the base of the groove, in the direction of the groove ( to give a bit more binding depth). "Wet" the groove with a very thin application of water-consistency cyanoacrylate (I use Stewart Macdonalds #10 "thin"). Then sprinkle a layer of rosewood dust into the groove until it just fills (a little over is OK but the stuff is hard and takes time to sand down) . Then apply just enough CYA to saturate the dust. Repeat if necessary to account for sinking of the wet matrix. Be careful not to apply too much glue as it will run like water once the dust is saturated. Don't touch the wetted dust as it will stick to anything.

Let it sit for an hour or so. I only use accelerator under emergency conditions as it smells lethal. Then using a flat sanding block (or wood plane with no blade) 6-8 in. long sand down the the filled area, being careful not to rock the block so as not to round the outer edges of the fingerboard or make a depression along the length of the fingerboard. I use a sequence of 320, 600, and 1000 grit, finish it off with 0000 steel wool and oil to taste.

The CYA glue/rosewood dust matrix is extremely hard and I've never seen subsequent wear. I had lots of practice doing this filling worn guitar fretboards (I think this whole process is documented somewhere at frets.com) where the resulting flatness is less of an issue. If you have concerns you can practice on a gouged piece of pine. The color of the rosewood dust, once wetted with the CYA glue is quite dark, but that's the price to pay for long-term correction of the nasty buzzing caused by a worn fingerboard.

fernandraynaud - 9-23-2009 at 09:13 PM

Thassa real clever, Freya, love it! But ... where do you get the rosewood dust from, maybe from the fingerboard :) ?

On the "ounce of prevention" front (I'm just treating my Sukar fingerboard), here is what 2 (thicker than usual) coats of Tung Oil looks like before final sanding:


[file]11327[/file]

It's very glassy, like hide glue in texture, but tougher and insoluble. The degree of smoothness after final sanding determines the brightening of timbre (if any) and how visible it is on the fingerboard. It sure is strange stuff. Light accelerates the polymerization.

You can fine-sand it into invisibility and just forget about it, only to check periodically that your vigorous vibratos haven't worn into the wood. If you see any wear, wipe another thin coat on, that dries overnight. If one wanted to remove it, it seems to turn liquid again in contact with liquid tung oil.


[file]11329[/file]

Yaron Naor - 9-24-2009 at 01:30 AM

Quote: Originally posted by freya  
I have filled several worn oud fingerboards with good success. First I score the fingerboard with a sharp x-acto along the base of the groove, in the direction of the groove ( to give a bit more binding depth). "Wet" the groove with a very thin application of water-consistency cyanoacrylate (I use Stewart Macdonalds #10 "thin"). Then sprinkle a layer of rosewood dust into the groove until it just fills (a little over is OK but the stuff is hard and takes time to sand down) . Then apply just enough CYA to saturate the dust. Repeat if necessary to account for sinking of the wet matrix. Be careful not to apply too much glue as it will run like water once the dust is saturated. Don't touch the wetted dust as it will stick to anything.

Let it sit for an hour or so. I only use accelerator under emergency conditions as it smells lethal. Then using a flat sanding block (or wood plane with no blade) 6-8 in. long sand down the the filled area, being careful not to rock the block so as not to round the outer edges of the fingerboard or make a depression along the length of the fingerboard. I use a sequence of 320, 600, and 1000 grit, finish it off with 0000 steel wool and oil to taste.

The CYA glue/rosewood dust matrix is extremely hard and I've never seen subsequent wear. I had lots of practice doing this filling worn guitar fretboards (I think this whole process is documented somewhere at frets.com) where the resulting flatness is less of an issue. If you have concerns you can practice on a gouged piece of pine. The color of the rosewood dust, once wetted with the CYA glue is quite dark, but that's the price to pay for long-term correction of the nasty buzzing caused by a worn fingerboard.


Thank you all for the info!
What is "water-consistency cyanoacrylate" is there water inside?
Thanks
Yaron.

freya - 9-24-2009 at 03:38 AM

The "water-consistancy" CYA that Stewart Macdonald sells is pure CYA that has the same consistancy and wetting properties as water. It is also great for glueing any sort of crack where deep penetration is needed. It can be sanded and buffed out just like Nitrocellulose lacquer and is as hard or harder. The only caveat is that it will also darken wood the same way water does though, unlike water, the darkening remains once it has dried. I've repaired dozens of (lacquered) cracked guitar tops and side with it and because it penetrates well into both sides of the crack and then crosslinks, the repairs are stronger than the original wood seam. Not recommended for unfinished oud tops as it is essentially like applying lacquer.

Yaron Naor - 9-24-2009 at 03:41 AM

Quote: Originally posted by freya  
The "water-consistancy" CYA that Stewart Macdonald sells is pure CYA that has the same consistancy and wetting properties as water. It is also great for glueing any sort of crack where deep penetration is needed. It can be sanded and buffed out just like Nitrocellulose lacquer and is as hard or harder. The only caveat is that it will also darken wood the same way water does though, unlike water, the darkening remains once it has dried. I've repaired dozens of (lacquered) cracked guitar tops and side with it and because it penetrates well into both sides of the crack and then crosslinks, the repairs are stronger than the original wood seam. Not recommended for unfinished oud tops as it is essentially like applying lacquer.


Thanks!
This is Ebony fretboard, do you think if I will put ebony powder and mix it with the glue it will stay long?, with the strings presure?

Y.

freya - 9-24-2009 at 04:11 AM

I've filled ebony guitar fingerboards with the glue/rosewood combo and it's held fine. Scoring the groove deeper with the xacto helps the bond. You might want to wipe the fingerboard down with naptha first just to remove excess oil (generally a good practice for bonding oily woods) Also the glue/rosewood dust combo dries close to ebony color. Just let everything dry completely before doing any scraping or sanding. Ebony dust should also work as well as rosewood but I can't recall whether I've actually used ebony dust. If water will wet it so will the CYA and once the CYA crosslinks everything is bonded together.

Yaron Naor - 9-26-2009 at 08:56 AM

Quote: Originally posted by freya  
I've filled ebony guitar fingerboards with the glue/rosewood combo and it's held fine. Scoring the groove deeper with the xacto helps the bond. You might want to wipe the fingerboard down with naptha first just to remove excess oil (generally a good practice for bonding oily woods) Also the glue/rosewood dust combo dries close to ebony color. Just let everything dry completely before doing any scraping or sanding. Ebony dust should also work as well as rosewood but I can't recall whether I've actually used ebony dust. If water will wet it so will the CYA and once the CYA crosslinks everything is bonded together.


Thanks for your answer and knowladge!
I will sure try it!
What is the meaning of this fraze:
"If water will wet it so will the CYA and once the CYA crosslinks everything is bonded together"
Should I put water on the glue before or after?

Thanks
Yaron Naor.

freya - 9-26-2009 at 11:32 AM

No, definitely don't put any water on it. All I was trying to say is the thin CYA behaves exactly _like_ water and will "wet" (i.e penetrate and spread) just like water. Another source of thin CYA is woodcraft.com 08X51 "Hot Stuff Adhesive". If you use CYA a lot, I'd also recommend getting some "Super Solvent". It's great for getting the glue off of fingers and will remove CYA from nitrocellulose lacquers without harming the lacquer, though it's always good to do a little test on the lacquer in an inconspicuous spot to be sure. If you've got a scrap piece of ebony around, practice on it first.

Yaron Naor - 9-27-2009 at 11:54 PM

Quote: Originally posted by freya  
No, definitely don't put any water on it. All I was trying to say is the thin CYA behaves exactly _like_ water and will "wet" (i.e penetrate and spread) just like water. Another source of thin CYA is woodcraft.com 08X51 "Hot Stuff Adhesive". If you use CYA a lot, I'd also recommend getting some "Super Solvent". It's great for getting the glue off of fingers and will remove CYA from nitrocellulose lacquers without harming the lacquer, though it's always good to do a little test on the lacquer in an inconspicuous spot to be sure. If you've got a scrap piece of ebony around, practice on it first.


Ok Harry, Thanks!
Now I understood complitly, Ok thanks
Yaron.