help needed old guitar

[hans jones]

My craft work is reasonable. How would be the best way to take on repairing the missing

'vine work ?'  ornate work.  Acceptable is what I am after. Any suggestions welcome.

 

http://earlyguitar.ning.com/photo/img-0676?context=latest

[Michael. N.]

You will have to produce some sort of fairly accurate paper pattern. Take a head on photo and print to scale or produce a negative image. Either will work. You could also use tracing paper carefully applied to the actual guitar.

I presume the original is in thin Ebony, around 1 mm thick but best to measure the original. Actually that may be some type of stained fruit wood given that the bridge has been shaved down.

Glue your pattern on to the Wood/ Ebony and cut using the finest hand fret saw blade. Magnification helps but it's not strictly necessary if the eyes are up to it. Sadly I now need the magnification. These were normally cut in batches with the veneer sheets glued together. That way you get identical and symmetrical patterns. It also helps to strengthen the pieces whilst they are being cut. As you are making single replacements it's probably best to glue paper on both sides of the Ebony veneer. Use water soluble glue.  Join/insert the pieces as best you can and I'm sure a bit of Black mastic will help.

The French marquetry cutters had their wonderful machines ' Chevalet de Marqueterie' (Donkey, to us) which could cut up to 8 patterns at a time. I suppose Lambert, Pons and Co. sent the apprentice to buy a dozen or so of their mustachios from the Parisian marquetry cutters. I assume it wasn't the Guitar makers who were cutting this stuff, especially given the power of the Guilds. I've often wondered if Lacote and the rest made those closed ring, consecutive Black/White rosettes or if they were bought in. There nearly always seems to be 10 white strips and it's such a common pattern. 

[hans jones]

I have some ebony but cutting it is another matter I will have to try various ways. I also noticed a similarity with the shapes so they may well be bought in as you suggested. Someone at the time was very skilled or had a clever machine for doing this work. I may find a way but it is going to be a learning curve for sure.

[hans jones]

And further to your observations see link and scroll down to look at Andreas Zettler of Wein

almost identical.

http://www.the-guitarworkshop.com/restoration.htm

I hope the link is allowed (mods)

[hans jones]

Exactly the same I would say. Sadly I have not mastered the cutting of the ebony so on hold at this moment. I have thought of making a mould from Plaster of Paris using the good bits from either side, then making another mould to get the orientation from the newly cast resin piece.

[William Bustard]

One past in-expensive solution I have used successfully whereby the present existing parts of the bridge are preserved:

 Get some ebony stained fruitwood veneer and use a knife. Carefully cut on the line with several passes until through. If you require thicker material then used two layers. After roughed out use a small emery board to shape then re-stain and finish to match the existing parts. I do not finish the gluing surface. Once applied I blend any joints after filling any (very) tiny holes with the finish.

The use of a well lit magnifying lens is recommended for best results. 

Using the plaster and mold idea while interesting may be more time consuming  because of the watery muddy mess and the amount of work as well as the possibility of failure and the un-even and greater mass around the bridge area of the table.(soundboard).

Making a complete new bridge would be easier.

[hans jones]

http://earlyguitar.ning.com/photo/img-0676?context=latest

Thanks for input. As you can see in the photo the missing bits are very small and delicate. I will look into your suggestions. The ornate stuff is just 1 or 2mm high and not much wider so quite tricky. It plays well but tuned dgcfad as a bit less stressful and suits my croaking.

[William Bustard]

Yes I understand. I have "whittled" small ebony pieces and they often crack or break if too thin which required repeating procedure until I got lucky. So the veneer method is much more stable when doing it.

More decription of the method follows:

Construction grade veneer is usually around 1mm so you would need 2 small pieces put together to start. If you only have regular veneer you may need 4 or so.

When doing this the last time; I glued the veneer up to a paper-board base which precut to the desired shapes. Cut the veneer to match the paper-board sand with very fine to the final shape and profile.

Then carefully removed the paper-board backing with a knife. Fine blades are required and a delicate "t-ouch"!

Once complete and  finished the way to look, dry fit to check it out, if looking right, glue to the area lightly with a thin layer of fish glue or some other natural glue held by green painters masking tape.

Good luck hope that helps. Repairing instruments can be a fun thing. I am currently working on a harp/lute/guitar. After 5 or 6 years of non-posting activity, I Just wanted to contribute a little to the forum.

Try checking out the threads on making the rose from wood, heres one,

http://earlyguitar.ning.com/forum/topics/material-for-vihuela-rosette

cheers

WB

[hans jones]

 I am encouraged to go on. The veneer method looks like the right way to go and judging by the work on your posted link page my requirements seem much easier. Will post back as to how I get but it may be in a few weeks.  

Many thanks h