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Old Dec 19, 2009, 04:13 PM
Practice Makes Precision
TDisaster's Avatar
United States, MO, Knob Noster
Joined Jun 2006
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Don, I've noticed you're a luthier so I have a question.

I have an older Stradivarius copy that I love to play, it was my great grandfathers, not sure how old it is. But my cousin had drawn on the neck with permanent marker. What would be the best way to remove this without harming the wood?
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Old Dec 19, 2009, 08:00 PM
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Bedford, TX
Joined Oct 2007
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Originally Posted by TheNightowl View Post
Be careful of that creeping crud, Dwells. All the rest of you, too.

I'm doing way too many reports on respiratory illnesses that are really laying people low, lately. Lot of people winding up in hospitals with pneumonias this year.

Nightowl
Thanks Owl, will do. Kinda took the wind out of my sail for sure...yuk!
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Old Dec 19, 2009, 08:37 PM
Hot Dawg Glider Pilot
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United States, TX, Weatherford
Joined Nov 2002
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TD,

You might try some 90% isopropyl alcohol in a small spot, with a Q-Tip. It probably won't hurt the finish. I don't do violins but they are probably finished with lacquer, like my guitars.

Jack
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Old Dec 19, 2009, 09:21 PM
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United States, OH, Bradford
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Originally Posted by schrederman View Post
TD,

You might try some 90% isopropyl alcohol in a small spot, with a Q-Tip. It probably won't hurt the finish. I don't do violins but they are probably finished with lacquer, like my guitars.

Jack
Well, um, not quite. Expensive, old violins are frequently finished with a multi-layer process based on oil varnish, each maker seems to have their own proprietary recipes and procedures. I have my own finishing procedure that is actually a hybrid of oil and spirit varnishes, with all-natural pigments, saffron in particular, and a ground layer based on "Vernice Bianca", a sort of primer dating back to Roman times, based on gum arabic, egg whites and honey (honey is a preservative, with anti-microbial properties), commonly used on violin-category instruments (including violas, cellos, etc.) and on antique furniture.

However, the vast majority (and almost certainly the Strad copy in question here) are finished with primarily "spirit" varnish. Lacquer is used only on the absolute worst VSO's (Violin Shaped Objects), like you would find in the toy section at your local big-box discount store. Quite different from guitar practice, where lacquer is the norm on virtually everything, including many of the best professional-category instruments.

"Spirit varnish" like what is on this Strad copy uses "spirits" (ethanol or "grain" alcohol) as the solvent, with various resins, principally shellac (NOT the same thing at all as the basic ingredient in lacquer) dissolved in the alcohol.

However, the neck under the fingerboard is traditionally left unfinished (makes a better surface for playing, doesn't drag on your fingers as much as a varnished surface would), other than natural skin oils developing a protective layer in the surface over time. If it's one of these but there was enough oil in the surface to keep the marker from penetrating, then rubbing (isopropyl) alcohol may work, the key word being "may". DO NOT use "denatured" alcohol (ethanol), it WILL attack any spirit varnish it comes in contact with. You can polish the surface afterwards with a new, clean Scotchbrite wood-finishing pad. You might try the Scotchbrite first, before getting out the alcohol, at the very least it should make the alcohol's job easier. Do not use Scotchbrite on the varnished areas of the instrument, it will ruin the finish.

If it's one of the few that did get a varnished neck, you might be OK and the isopropyl may take it off. However, if the marker soaked into the wood at all, you're pretty much out of luck. It may be possible to sand it off (along with the surrounding wood) if the neck was left over-thick to begin with, but significantly reshaping a neck is probably something best left to a luthier.
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Old Dec 19, 2009, 09:41 PM
Practice Makes Precision
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It does have a varnished neck. I'll try the isopropyl, thanks.

Here's a few pictures if you guys wanna see it. (ignore the horrible quality) Oh, and another question, in the one picture you can see the chip on the back. Is this fixable? A girl in my orchestra class one year decided she was going to borrow my violin when I wasn't there and dropped it. etook it to the local luthier and he said he wasn't able to fix it because of the type of wood.
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Old Dec 20, 2009, 12:05 AM
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Originally Posted by TDisaster View Post
It does have a varnished neck. I'll try the isopropyl, thanks.
Make sure it is indeed varnished (not completely clear from the pics). If it isn't, then the alcohol might just drive it in deeper.

Quote:
Here's a few pictures if you guys wanna see it.... in the one picture you can see the chip on the back. Is this fixable? A girl in my orchestra class one year decided she was going to borrow my violin when I wasn't there and dropped it. We took it to the local luthier and he said he wasn't able to fix it because of the type of wood.
I've fixed FAR worse than that. I'm just finishing one now where the entire section of the back around the heel of the neck was broken off, then they tried to glue it back together with the wrong kind of glue (for a whole shopping list of reasons, the only kind of glue that should EVER be used on a violin is hot hide glue, the kind that you mix up from granules and then heat to 140-155 deg. F for use), then they lost the broken piece entirely. I had to find some wood with matching grain ($25 for an 8 ft piece of figured quartersawn maple, which I only used about a 3" square piece of about a foot from one end), carve out a scarf joint into the back, chalk-fit (if you think cutting out wing ribs by hand is tedious, you should try chalk-fitting!) and glue in the new piece to it, recarve the whole area, make and fit a new top block, and wood grafts on the ends of the "ribs" (sides of the violin) and heel of the neck, reset the neck and reassemble the whole thing, then retouch the finish. The ribs around the bottom block were in about six pieces as well, and the bottom block also needed to be replaced. I'm in the final stages now of touching up the finish and then beginning the setup, new soundpost, fitting and voicing a new bridge, etc. I've included a couple pics.

As far as the chip in yours, hardly looks worth bothering with, unless it's deeper than it looks in the photos. "Old and beat-up" looking is "in" these days, so unless it's really deep I'd be inclined to leave well enough alone. However, if it's enough to be a significant problem, grafting in a new piece should not be too much trouble. Tricky part would be touching up the finish and getting it to match.

I thnk we've managed to completely hijack this thread at this point, so unless the rest of the folks here really want to learn about extremely precision woodworking techniques such as chalk fitting, or how to learn an entirely new definition of the term "sharp" when it comes to tools (as well as how to achieve it), or how those little ornamental Victorian-filligree-looking thingies on the bridge are actually a tone and volume equalizer for the individual strings, at this point it might be best to shift this discussion to private e-mails.
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Old Dec 20, 2009, 12:26 AM
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Don, I have to admit I'm enjoying your sharing your knowledge.

I have an older friend that builds classical guitars and repairs instruments of all kinds, or at least he used to in better times, I built a new workshop for him during the middle of last year to his specification. I'm totally untalented in this field, but wooden musical instruments, most welcomed, its all related by harmonics and resonances etc I suppose, Don't we fly with them?
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Old Dec 20, 2009, 12:36 AM
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I'm finding an amazing amount of technology from lutherie that applies to model airplanes, and vice-versa. I'm even using violin & guitar technology on some of the UAV & giant-scale constant speed propeller work I'm involved in.
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Old Dec 20, 2009, 09:57 AM
Practice Makes Precision
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I'm positive the neck is varnished. That's the one thing I hate. My hand always sticks when I shift .

Thanks for the help! The repair looks amazing.
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Old Dec 20, 2009, 10:25 AM
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Originally Posted by TDisaster View Post
I'm positive the neck is varnished. That's the one thing I hate. My hand always sticks when I shift ....
That's precisely why they normally are not varnished!

I had a customer not too long ago, a jazz guitarist, who had me strip the varnish off the neck of his guitar for the same reason.

Wouldn't be too difficult to scrape the varnish off the neck, sand & polish it out and treat it with a little bit of walnut oil. Do you ever get over to the Dayton, OH area?
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Old Dec 20, 2009, 10:36 AM
Practice Makes Precision
TDisaster's Avatar
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Originally Posted by Don Stackhouse View Post
That's precisely why they normally are not varnished!

I had a customer not too long ago, a jazz guitarist, who had me strip the varnish off the neck of his guitar for the same reason.

Wouldn't be too difficult to scrape the varnish off the neck, sand & polish it out and treat it with a little bit of walnut oil. Do you ever get over to the Dayton, OH area?
Almost never. That's quite the drive from North East Pennsylvania.
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Old Dec 21, 2009, 07:45 AM
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ARF superbalistics

I think i might have mentioned that this Discus scale ARF i am throwing together over christmas would need an amount of hands on attention, and its true, its under the knife for good reason, wood work needs to be done 'fore and aft to make it even slightly airworthy.

The first pic below shows the factory wing joiner tube setup, i hope a trained design engineer didn't come up with this- but then, it is from China...

I was about to to do the usual RCG Discus mod for this glider by replacing the very thin and flexy plastic rod joiner tube with a metal one, but quickly realised that this would cure nothing at all, the tube is in no way integrated with the spar system 1/4" in front of it- genius hey.... in fact a metal tube might only improve the chance of a rip-out under load.

Seeming i would like to fly thermal, some aerotow and slope with this nice looking scaley I decided to try and integrate the tube with the spar by boxing it in alongside the spar system, whatever the heck these are, i might find out one day if it gets into a good bingle.

Tomorrow I'll cap it off and replace the 2mm top sheeting i cut back to get inside. Hopefully it will then sustain a bit of winching and high starting, and be more airworthy for the landing rigors of slope soaring.

Then again, it only cost $130 AU, so what can you expect. $1300 and you would expect not to have to do any of this. But still its a good bargain if you are a builder, they look and fly nice, although a little ordinary for thermalling...
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Old Dec 21, 2009, 09:15 AM
Silent Wings
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United States, TX, Amarillo
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Steve
Looks like you have the handle on it. I'm sure that the strength will be greatly improved.

Tis the season, and to all friends here on the thread we hope your Christmas will be a joyous one!
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Old Dec 21, 2009, 09:49 AM
Hot Dawg Glider Pilot
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United States, TX, Weatherford
Joined Nov 2002
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Yep, tis the season... Merry Christmas everyone! Santa came to my house early. I guess he knew I'd be in Ft. Worth... I don't believe I'll have any trouble getting the first Journey flying by the end of January. The hardest panels are built, and If I can't get my carbon problems ironed out, I have another solution for that. And then there's that dark-side project... the Xploder 4000... Oh well, at least I'm putting the woody first...

Darth
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Old Dec 21, 2009, 05:10 PM
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Lol, but for how long, Darth.. If you are anything like me you will have trouble resisting playing with a huge mouldie like that, my woodie build would sure as apples slow down.

Merry Christmas to all my woodie building friends here at RCG, may we all have something fun to occupy what building time we might get over the season, and get to spend some time with friends and loved ones, and most of all... survive them.


EDIT: My christmas present will be a little late this year, but thats ok because Santa Ray is likely to be a very busy chap over the silly season.
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