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markdavenport
Dec-28-2004, 5:34pm
I have a flat-top parsons mandolin,
oval hole... bought it a few months back...
did not notice the crack...maybe just happened..
or maybe buffed over by seller (??).. it's about
1" long at the bottom of the sound hole... very
small in size. any way to repair the crack or keep
it from getting bigger without going to major expense..

sunburst
Dec-28-2004, 7:05pm
Yes.
Unless you have some experience, I'd say get it to a luthier/repair person.
A little super glue, properly applied, should do it.

Shouldn't be too expensive, My price for simple crack repair is $10 for the first inch.
Finish touch up, cleats, etc. are extra. That should give you a ballpark idea of what to expect.

b.pat
Dec-29-2004, 8:56am
Sunburst,
Forgive a stupid question, but when you mention a "cleat" are you talking about a small piece of wood glued to the end of the crack to prevent the crack from progressing further? http://www.mandolincafe.net/iB_html/non-cgi/emoticons/rock.gif
B.Pat

sunburst
Dec-29-2004, 9:07am
Yeah, a cleat is a wooden patch inside the instrument. It is usually there to align a crack, or to add strength to a crack that no longer fits together well to be glued.
In fact, tho, a lot of them have been put in just to make the owner and repair person feel better.

MandeMando
Dec-29-2004, 12:21pm
I was going to start a new topic, but my question fits somewhat nicely here. #I appologize, first, since my problem is a crack on a fiddle, not a mandolin, however I promise you, my mandolin is my passion! #It is just that where I live (Mali, west Africa) there is no hope of professional help and so, out of desperation, I thought I'd try the fine folks who frequent this sight. #OK, are you sufficently buttered-up? http://www.mandolincafe.net/iB_html/non-cgi/emoticons/biggrin.gif
As I said, my problem is a crack on the top of my fiddle, right under the tailpiece, beginning at the edge and growing, over the past year, towards where the sound post is. #At this point it is about 2 inches long. #It was 1 inch long exactly 1 year ago. #I have meticulously kept a Dampit in the body, but the humidity here takes such swings over the course of a year, that most fiddlers give up and don't try keeping one around. #
Anyhow, I was going to try some superglue, but before doing so, thought I'd ask you all. #I'm encouraged that this might be a reasonable solution, given Sunburst's response above.
Thanks for any help you can offer.

sunburst
Dec-29-2004, 12:53pm
Superglue is fine for guitars and mandolins, but is frowned upon for use in violins.
A violin should be repaired with hot hide glue.
Superglue will work, but violin repair people expect repairs to be done with hide glue, and in the event that a pro works on this violin in the future, (a likely thing, considering how long a violin can last) he or she will be expecting hide glue in that repair. Also, superglue doesn't work as well with violin varnishes as it does with lacquer and some of the harder finishes used on mandos and guitars.

It isn't as hard as you might think to repair that crack, and while I would recommend getting it to a pro, I'll give you a quick idea how to do it, since you can hardly do any irreversible damage by fixing it yourself and you live where pros aren't to be found.

You'll likely need the sound post out in order for the crack to close tightly and align properly. If the crack is not tight and aligned properly, stop and get further instructions.

Get some hide glue, mix it with water as directed by the manufacturer, and heat it to 150 degrees F in some sort of double boiler. A search will likely bring up several discussions on hide glue and it's use.
Brush some on the crack and press and work it into the crack with your fingers. Keep doing that 'til there is glue all the way through to the inside of the violin the full length of the crack.
Use a soft brush and some hot water to clean the glue off of the surface, and let the glue dry undisturbed for 24 hours.

This will work for a mandolin or guitar also, by the way, but is more expensive, so for the mandolin that started this thread, I recommended the super glue.

Also, I know that there are trained violin repair people that frequent this site, so hopefully someone will post better information. I just thought I should warn you that super glue is not generally considered proper for violin repair.

markdavenport
Dec-29-2004, 1:30pm
appreciate the imput... for the super glue
repair.... do you put it on the outside or
inside??

for the cleat on the inside... what type
of wood would you use... type of wood
as well???

thanks

sunburst
Dec-29-2004, 2:01pm
When you have the luxury of access to the inside, the super glue can be applied there.
If the crack actually comes out to the sound hole, a tooth pick loaded with a small amount of glue can be applied to the end of the crack and the glue will wick right along the crack. The right amount of glue will not show, too much can be soaked into the corner of a paper towel applied to the end of the crack.

Cleats can be any wood that glues well.
I like to use spruce for tops and light colored woods like maple, and mahogany for darker woods.

PaulD
Dec-29-2004, 3:55pm
This is in response to the violin crack, but it's going to sound lame because I never know what to call the little part I'm going to refer to! http://www.mandolincafe.net/iB_html/non-cgi/emoticons/sad.gif I'm sure Steve or someone with real experience will jump in and name that part or tell me I'm full of it! http://www.mandolincafe.net/iB_html/non-cgi/emoticons/smile.gif

One thing I've been told to look for when violins crack under the tailpiece is to make sure the little ebony "saddle" that the tailgut wraps around is not too long for the notch it fits into. In case this isn't clear, the tailpiece is held on one end by what I'm referring to as the tailgut, which may not be the corrrect term. The tailgut hooks to the end pin and bends around the saddle thingy. The top is notched to accept that saddle, but if the notch doesn't allow enough clearance as the top shrinks, the saddle will force a crack to open (wood doesn't compress well along the end grain).

Like I said, I'm sure someone with experience will tell us if that's a valid concern, but if it is you'll want to make sure that "saddle" fits properly before trying to fix the crack.

Paul Doubek

sunburst
Dec-29-2004, 4:50pm
Yep, it's called a saddle, and those cracks are pretty common for the reasons you've stated.

MandeMando
Dec-30-2004, 11:23am
Thanks for the help, and for your indulgence as I hijacked the topic! Now if I can just find some hide glue ... perhaps the local leather workers regularly render it? Also, I'll check on the clearance for the saddle. Thanks Paul and John!

PaulD
Dec-30-2004, 11:45am
John... thanks for the feedback. As I've stated, I'm comfortable with woodworking in general but I don't necessarily feel qualified to answer luthiery questions.

Brad... you don't say if UPS delivers in Mali, but I would think you would be able to find what you need (hide glue and the rest) via mailorder through one of the luthier suppliers around the globe. There are good suppliers I could mention here in the U.S., but part of the attraction there for me is domestic shipping... if you're outside the U.S. you should probably evaluate other sources in addition to the U.S. sources.

Paul Doubek