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Pretty major project, Ray. You are going to have to take it apart, without question, and some of it will be pretty tough to accomplish, even if you have all the time you want. Two weeks is a pretty tight schedule, in my mind.

Button graft, mising wood in several places, badly broken rib, etc. Major repairs. Have you done any of this before? I know you have built a bunch from scratch, but I can't recall you discussing repairs before. Have you got the Weisshaar book?

I would find that a fairly daunting project, and I have done all those before. One thing at a time, though, if you are committed to doing it. Maybe someone with more skill can give you some pointers. I don't want to risk pointing you in a wrong direction.

Chet

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Not an easy fix... especially if you have not done it before, but it can be done... lots of thought and time. What is the value of the violin?, Is it hand made or factory? You will need to disassemble, and do a button graft and a rib doubling... at least.

First you will need to decide is this a fix to be playable or a proper restoration.

Good luck, Mat

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I have done a button graft before and it's not easy. Here is a picture of the one i did 8 or so years ago and i would do a couple of things diffrently now.

1) have a MUCH bigger counter form ie plaster cast

2) not go through the top of the button so i didn't have to make a ebony crown too.

Hope this helps with perspective of the job you have on hand.

LINK OF PICTURE

Jesse

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thnak you Chet, i have the highest regard for your words. yes, i'm beginning to think 2 weeks is unrealistic. picked up a real doozy didn't i?

no i've never done a button graft and i've never seen the Weisshaar book.

i'm taking it apart while gooling button anything right now. its going to be a long night.

than kyou Mat. rib doubling...got it! i'll start making cauls asap. yes, i'm disassembling it presently to have a better look-see at what is going on.

its a trade fiddle. i have no clue of its value. and after i get done with it, i'm going to guess it'll be worth less.

Thank you Jesse.

the picture helps a lot. i think i can do it. the button break took a bit of wood on the treble side and its no where to be found. in doubling and grafting new wood, would i have to cover areas left and right pf the button or should i keep the graft a straight "tongue"?

something else came up i didn't see befroe: the fingerboard was once shimmed to make up for an angle issue i assume. would this be the time to remnove that shim, reset the neck for a better angle or leave it and set the neck as is? the shim job wasn't great.

warning: attached pic is rather long.ish

thank you

Ray

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oh no... what is a clavette?

http://www.maestronet.com/forum/index.php?showtopic=319831

Look at Oded's post #12

The only thing I would add to that is use a piece of wood that doesn't match well and orient the grain so there is a clear contrast to the rest. This way it will be more obvious to the next person who repairs the instrument that it is a clavette and not simply a back piece for a neck reset. Does this seem clear? It's less work than a button graft and you get to keep the original button.

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What about a clavette instead of a button graft?

Yes that would work better with the time constraint. Though i don't like them in general. Seems like the same amount of work for a lesser fix. I know it's easier but it doesn't feel that way. :)

Also this would be the perfect time to fix the angle of the neck but with the time constraints you have i wouldn't bother unless it's absolutely needful.

Jesse

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this is one of those rare cases where i would remove the back, not the top, if nothings wrong with the top theres no reason to remove it, and with the back removed it will be much easier to repair the button, otherwise youd have to remove the top block, reset the neck etc if you only took the top off

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thank you Matthew Noykos, Jesse and lyndon

i understand what a clavette is now. i will toss a coin and figure out if i should go with a graft or a clavette. and yes i think the back definitely needed to come off. i wanted to remove the top too so that i could get to the ribs andf do a proper doubling.

so here's where i'm at...

i think the top[ block isn't really doing its job. it was a bad fit all round and i am thinking about replacing it. i understand the rationalw behind conservation and do no harm as the first rule. and i am aware that this particular instrument is perhaps not of great monetary value. at what point do i ditch conservation or should i stick with it come hell and high water?

i undefrstand the rationale behind using hide glue. is thdere ever a good time to use AR, CA or PVA? if so, what would i need to know to make that judgment?

need to get some sleep before work. will post update tomorrow night. or tonight rather.

thanks

Ray

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Here's a very similar rib repair, a fracture to one side of the end block. You'll have to make a supporting wooden mold like the one in the photo below. You do everything in this mold. First glue the two parts using animal glue only. When the rib is glued and sitting comfortable in the mold, scrape/file the thickness around the break down to .5mm or less and glue a new piece of maple on to this surface. When clamping this piece of maple you will have to use a sand bag so as to disperse the clamp pressure evenly. Re thickness the rib after. Delicate work, not to be rushed. Good luck!!

thank you just the same lyndon. have a good one.

so the pieces fit back nicely, but there are chips missing.

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.... is thdere ever a good time to use AR, CA or PVA? if so, what would i need to know to make that judgment?....

Don't even think of using anything but fresh hot hide glue! All of the synthetics can creep understress in time and especially if ever exposed to heat. Hide glue has stood the test of time.

Good luck!

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greetings to all

here's a fiddle belonging to a friend of a friend that i've been asked to fix.

before i jump on it, i would sure like to hear some suggestions from the experienced folks on this forum

i have two weeks.

thanks in advance.

r

+++++++++++++

Hey, A piece of cake. (Just kidding)

Seriously I think you can do it. However, like anyone else who is dong

such a repair, you have to think through it before taking each srep. Pretty soon you will finish all the necessary steps.

Since it is a trade violin, the fear is minimum.

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http://fiddlehack.com

lay the back flat, lightly take off the high chunks of the old glue that keep the button from lining up properly.(I mean off of the plate gluing surface area)

practice putting the button where it goes, so you can see that the fibers are lining up and locking together.

lay the back out on two pieces of soft thin (4mm thick or so) stable wood that can be cut back off,,, one piece some what larger than the break,the other piece just to keep things level .. do not get glue on any surfaces that need new wood,as you won't be able to clean this up easily.

making mistakes of this nature is what takes all the extra time.

glue the plate to this scab wood,(not too much glue,just enough) along with the button,perfectly srtaight.

after it dries piece together all the missing parts.glue it up.

Make a cast…

To make a cast of the upper bout,( dozens of ways to do this) To be fast and dirty I would cut out 3/4 plywood close to the shape,10mm or so over,(upper bout to the corners) place some short screws around the perimeter of the wood,like along the purfling, to hold the plaster on.(like grabber screws). Place them so they will not touct the plate if the wood rests on the arch..

place two 1/2" bolts through the center to hold in a sturdy vise ,(like smashing two of your fingers in a book,,,it will keep it from twisting).

Don’t have a vise ?,,then forget the bolts,,,,,,,,,,,,, then after you’ve made the cast,,screw another larger piece of wood to that with which you can clamp or screw that to a table,,,,

,,you can build something with a dam around it if you want,,,I wouldn’t,,,,the contraption that I described can be reused 100’s of times,,,,just break off the plaster with a super giant sledge hammer mix and pour !!! You just need to be able to hold the work firmly.,,,,,,,,,, Or make a full cast or half or whatever

You will want to be able to clamp the work to the mold while you work it. if you knock it out to the floor,,,,,,,,,,,oops

now is when you cast it.

Lay the plate on something flat this kind of thing doesn’t need a vaccume box.place more of your scab wood around it so the plaster ends up level with the gluing edge of the plate and rib line.

Cover it with saranwrap,,, tape it down so there are no excessive wrinkles,,don’t pull it too tight. And tape it away from the plate ,,You want a decent impression of the edge.for support

Mix the plaster thick ( I like to add a little rock putty,,,makes it much tougher) generously glob on the plaster over the area in question

If you’ve never done this before,,practice mixing small amounts,,and play with it to learn about its behavior paterns.

Once you learn how easy and helpful and FUN !! it is to cast ,,you won’t be able to stop !!!!

You’ll find all kinds of uses for this..

Place the plywood and goosh it carefully on the work,

If the plaster is thick you must work fast,,,,(if you are in a hurry you must make it thick),

If it is thick you glob it on,,,,push in your holder plywood dealie’’use a putty knife to push the plaster around the edge where it goes,,in a couple of minutes,,it will get stiff ,,,then trim the edge off clean,,,,,,in a few minutes when it is set and getting warm,,,, get it off the plate before it bursts in to flame,,just kidding!

Really though you can pull blisters in the varnish if it is mixed strong and just left on the work.

Don’t do this and go to dinner,you could come home to a well done fiddle.

A warm oven will speed up the dring time of the plaster,,,especially moving air ,,a fan ect,,

DO NOT put a plate back into a damp mold,,,,,,,use some saran wrap if you are in a hurry,,

But only for a little bit,,,,do not leave it in there..(let it dry)

The mold will take a day or two to dry depending ??????

Now with the plate in the cast

Remove the glued on scrapwood,with planes chisels coarse files or whatever

cut out the shape of an "A" pointing tword the endblockl through the button continuing through the block area using knifes and chisels and files and scrapers. small scrapers with 90o or less corners so you can make a clean edge joint..,,,take this down to the purfling so you are replacing all of the wood. take some strong maple, and cut out your "A" shape, flat on the bottom and 90o on the sides.

With a little matching you should be able to match the profile of the sides and glue it in.

I usually orientate the grain to be paralle to the rib gluing surface so as to facilitate easier removal at a later date, without excessive grain splitout. You may need to double up more of the edge than the button area,,,just go for it..,,do it all in one piece and forget the “A” shape…

Just be careful and watch what you are doing, It really isn’t that tough,,

Nothing can take the place of experence.....

good luck,,have fun

Evan

http://fiddlehack.com

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thank you bcmviolin, Mat, Fellow and Evan

i will attempt the rib doubling first because i've done one of those haphazardly in the past. this time i will pay close attention to the excellent pictorial example and learn from it.

yes i will stick to hide glue. if i'm still awake tomorrow night, i will get plastered, along the detailed instructions from Evan. many thanks for taking time to explain.

i took apart the neck this morning. its going to need a new nut. i will leave off the badly executed shims and reset the neck at a better angle later.

i have decided to go with a button graft and a new neck block. thank you all for the information that pointed out where i needed to go next. will be digging into the archives yet again and googling the night away.

the top is fine as far as i am concerned. i don't think there will be time to take care of a few minor things that bug me. i have to let them go.

grateful person

Ray

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Here's a very similar rib repair, a fracture to one side of the end block. You'll have to make a supporting wooden mold like the one in the photo below. You do everything in this mold. First glue the two parts using animal glue only. When the rib is glued and sitting comfortable in the mold, scrape/file the thickness around the break down to .5mm or less and glue a new piece of maple on to this surface. When clamping this piece of maple you will have to use a sand bag so as to disperse the clamp pressure evenly. Re thickness the rib after. Delicate work, not to be rushed. Good luck!!

hello bcmviolin

i meant to ask, why did the lower corner blocks looked the way they did? should i do the same somehow?

thanks.

Ray

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Hi Ray, I presume you mean the split corner blocks? It's a way of simply removing the lower ribs with minimum disturbance. Just split the two blocks in half down the grain with a very thin blade (see attached photo) and when your finished the repair just glue the blocks back together. Best of luck, Brian

hello bcmviolin

i meant to ask, why did the lower corner blocks looked the way they did? should i do the same somehow?

thanks.

Ray

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Hi Ray, I presume you mean the split corner blocks? It's a way of simply removing the lower ribs with minimum disturbance. Just split the two blocks in half down the grain with a very thin blade (see attached photo) and when your finished the repair just glue the blocks back together. Best of luck, Brian

thank you very much Brian. i was tempted to split the block but wasn't confident that was the right thing to do. i will do so next time if the need ever arise. i learned a lot from your pictures! thank you.

I really hope I'm wrong but....... on the photo of the inside of the top plate there appears to be a glue line in the vicinity of the soundpost. Is there any indication of a repaired crack on the top side?

Barry

hello Barry , sorry for the lousy picture, i was trying to keep the file as small as possible. it's actually a pencil line. not sure why or how it got there. on the back, someone also drew a circle where he or she thought the sound post had to to go. the soudpost has thin strings tied to the top and bottom end. no sound post cracks on either plate.

spent too much time taking it apart...

taking a break tonight. information overload.

hope to come back stronger in the morning.

thanks

Ray

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Your very welcome Ray, glad to be of some help. I'm no expert myself, the pictures I posted are of a project I was working on at a Hans Weisshaar workshop in Mittenwald earlier this year with Gorge Ettinger from LA. I find it very difficult to learn without seeing the particular work actually being done in front of me, or through decent explanatory photographs. You're very courageous taking on a project like this one. Looking forward to seeing the finished results. Brian

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