First repair

[Domhnall]

I just recently bought a beat-up kentucky A mandolin off of ebay. The reason being, to fix it up and hopefully learn some lutherie in the process. However, to be able to do this, I must admit I am in need of help. I've already talked to a local violin repairer about it, but I dare say the mandolin community ought to weigh in on it as well.

The Mando (http://cgi.ebay.ca/ws/eBayISAPI.dll?ViewItem&ih=006&sspagename=STRK%3AMEWN%3AIT&viewitem=&item=160122688647&rd=1&rd=1)

This Mando has had some bad repairs done on it, that will need to be undone before it sounds its best, the neck was glued back on poorly and brown paint was used to cover it up.

Follow the link for pictures.

What I need to know is what glue do I need to fix the back back in place, and reattach the neck properly?

How does one unglue the neck? (most likely glued with cartpenters glue)

How would you go about removing the paint? (I'd rather not have to sand it if I can get away with it)

Finally, is it worthwhile to touch up the varnish? If so what would you recomend?

Thanks,

Dan

[martinedwards]

Well, worst case scenario, you have a case, a set of tuners and a tail piecs for less then new!!

the glue SHOULD let go with heat.

get a clothes iron and set it on top of the frets at full heat for at least 30 minutes, maybe an hour.

I lifted the neck off a mando for a re-set this week exactly like this.

the BEST way to remove the paint is to sand it.

the best glue to use is hot hide glue, but ordinary carpenters glue would do fine.

DO NOT use gorilla glue.

[martinedwards]

oh yes, WELCOME!!!!!http://www.mandolincafe.net/iB_html/non-cgi/emoticons/biggrin.gif

[Antlurz]

I think I'd be prepared to find a "Surprise" wood screw buried in that curve of the neck heel under that paint and body putty where they tried to pull the neck back to the body.

If so, it would be an ideal place to insert a steam tube for pulling the neck.

Ron

http://i18.ebayimg.com/07/i/000/a2/24/7c02_12.JPG

[Stephanie Reiser]

I think it's a great idea to purchase that poor instrument with the intention of practising repair work. It obviously has a neck pulling forward. It will be interesting to discover what type of neck joint is in there. I think Ron is right, that you will find a screw under that goop.
Good luck!

[ErikAitch]

I think I'd be prepared to find a "Surprise" wood screw buried in that curve of the neck heel under that paint and body putty where they tried to pull the neck back to the body.
Great call, Ron!

That's exactly what it looks like now that you mention it. Slipping a feeler gauge or similar into the separation might tell the whole story without making a mess.

[Domhnall]

Well, worst case scenario, you have a case, a set of tuners and a tail piecs for less then new!!



That's the way I am looking at it actually. I'm hoping that it will sound at least as good as my current mando (a cheap Johnson) when I am through with it.

How much better is Hide Glue over Carpenter's Glue? If it is a huge advantage I'd have no problem getting some and preparing it, but if it isn't that much better I'd rather go with the devil I know.


I think I'd be prepared to find a "Surprise" wood screw buried in that curve of the neck heel under that paint and body putty where they tried to pull the neck back to the body.

Good to know, I'll be careful.

Thanks all,

Dan

[Antlurz]

Hide glue is the time tested old standby, but there is a learning curve. Rather than a generic "Carpenters Glue"I'd go with Original Formula Titebond. (red label)

Ron

[Domhnall]

Yeah, Hide Glue is the best, but it seems like a tonne of work, considering how much of it I need. I'll take your advice on the Tidebond.

The Mandolin is on its way, so I'll let you all know how bad it is when it gets here.


Dan

[nelson_luthier]

After dealing with that neck you might want to completely remove the back instead of just re-gluing the failed section. You did say you bought this to learn, right? This will allow you to do a complete inspection of the interior as well as learn something about binding. #You will also have an oportunity to check the graduations and make adjustments if needed.

It's not really clear if you want to just touch this up or re-finish. I agree that sanding and/or scraping is the ticket for removing the finish. If it is a varnish you can remove the bulk with alcohol, but almost any other finish will require harsh chemicals that can harm the glue joints as you try to remove the finish. Lots of people will disagree with me on that, but why dink around with nasty chemicals when there are perfectly good toxic free alternatives.

Greg N

[Domhnall]

I think I'd be prepared to find a "Surprise" wood screw buried in that curve of the neck heel under that paint and body putty where they tried to pull the neck back to the body.

If so, it would be an ideal place to insert a steam tube for pulling the neck.

Ron

You were right there is a big ol' screw in there.

Also, the side of the mandolin had a big mess of putty under the paint, and it was covering up a nasty crack. I don't have a camera so I can't post a picture. I think I'm going to have to take Greg's advice and take the back off to fix it that up. And I had already decided to fix up the binding so that only makes sense. I just have to hope I can put it back on afterwards. I didn't think I'd need at first - but now I have enough gluing to do to justify ordering hide glue.

Dan

[Antlurz]

Well, she's no silk purse at this stage of the game, but it definitely can be a good lesson in repair work. Might even make a really nice player too if you do a good job.

take your time and don't cobble it. Learn how to pull the cracks back together, make a form to hold the rib shape in place if necessary. Learn the best way for shimming the neck joint to get a good fit. Lots of things there for experience and maybe a nice playing mandolin when you're done, as well.

Ron

[ErikAitch]

Unflavored gelatin and hide glue are much the same thing, so that's a way to get a little at the grocery store. Although a pound of hide is about the price of a dozen gelatin packets, I wouldn't use the glue for making marshmallows. IIRC, gelatin's a bit higher gram strength than the hide commonly used for luthiery, meaning it gels faster, which makes it good for practice. http://www.mandolincafe.net/iB_html/non-cgi/emoticons/biggrin.gif

[Bill Snyder]

Using gelatin (http://www.frets.com/FretsPages/Luthier/TipsTricks/KitchenGlue/kitchenglue.html) when no hide glue is available from Frets.com.

[buddyellis]

One potential problem with Hide Glue in this case is if the joint is already contaminated with something else. Hide glue really needs fresh wood so you'd need to be relatively careful about getting the old glue residue out of the joint (this is the case anyway, but with HHG, even more so).

In a case like this, I’d probably just use tightbond, depending on how the joint was. If you can get the joint real clean, though, HHG isn’t THAT much harder to deal with, especially on a properly setup neck joint, than Tightbond, et al. Just have to work quick.

You can certainly use Gelatin. My first two mandos were put together with Knox. It’s just a relatively ‘expensive’ way to go, since you can buy a pound of HG for not much more than a box of Knox. :-D