Can anyone recommend some easily-obtaibale glue that would work well for the following job:
I am repairing an old stringed instriment (a lute). Part of the work involves sawing the neck off and resetting it at a slightly different angle. I think the best way to strengthen the joint would be with a couple of dowels. The problem is, when I drill the holes for the dowels, I have no way of making sure they will line up exactly (and be exactly in-line). So, I guess the only thing to do is make one of the holes slightly oversized, to allow some play - then use a glue which will fill the excess space. I was thinking of using epoxy (Araldite), but I'm not sure if that would be the best choice. The wood looks like it might be maple and is around 80 years old.
The mating surfaces of the nack and body after sawing the neck off will be as follows: the neck end will be all end-grain. The mating surface at the body will be partly end-grain and partly side-grain. So what is the best glue for going end-grain to end-grain? Hopefully the same glue I'll use for the dowels....
I don't have your glue answer; but would like to suggest that you build a simple drilling jig using steel bushings (something like: )
I don't have instrument-making experience; but I'd guess that you'll want both mechanical and accoustical "strength" in the joint - and would guess that an oversized hole (even if glue-filled) would compromise that.
No, it involves steaming the old joint apart and re-setting it, not sawing cross-grain. I'm no luthier, but I know you don't saw through necks !
If you're repairing a broken neck, I believe long scarf joints are the way to go, not dowels. Are you expecting to play this thing afterwards?
And aren't you the baboon who posted to uk.d-i-y about epoxy and bridges ? I'm beginning to suspect a troll here. How about you leave the musical instruments alone and stick with molesting goats on bridges ?
Hi Morris, Thank you kindly for your input. The above URl seems obsolete, but I think I found the page you meant. I'm not too worried about accoustic transferrence. I guess your drilling rig idea might be good in ideal circumstances, but it is actually rather necessary to have some play in the dowel while the glue is still wet, in order to get the alignment of the neck exactly right prior to glue setting. I 'd have grave doubts about achieving the exact corect alighnment via use of a jig. I'm sure that if the joint is strong, the acoustic properties will be adequate. So, if I may rephrase my question: If I use an oversized hole for the dowel, which glue would you use? (Anyone?) Please bear in mind that the sawn neck-end will be end-grain so the adhesive needs to be good for that too...
I think in this case, it's the only way. The way a lute is constructed, the whole thing will come apart at the seams if I try to steam the jount apart at that point.
Up to the above paragraph, your input was helpful and appreciated. I really can't see the call for the sudden outbust of insults. Maybe ask your doc to change your medication...
What if you clamp the body so that the bodt laminations can't come apart when you steam the neck loose? Might wanna try a Luthier's newsgroup for better information.
This is not intended as an insult, but... Yikes. It sounds like you're about ready to ruin a cool old instrument that has lasted for 80 years (or more?). The repair you described kind of makes me cringe.
Try getting some guidance from a luthier, or have them do the repair. You might try asking over in the "other stringed instruments" section on the
formatting link
board. There's also a new book (within the last year I think) available on lute construction from GAL.
formatting link
'm not that familiar with lute construction and how the neck joint works. But I know there are methods for steaming guitar necks apart without making everything else fall apart.
Use ground hide glue (not liquid hide glue)... The idea is to keep repairs and modifications as reversible as possible. With epoxy, you're going to have the final word on this instrument.
Also, make sure a neck reset is what the thing actually needs. If the neck is warped or the top is warped, a neck reset might not really help it int he end. If all you need is to raise the action slightly, what about making a replica bridge that's just a little higher?
assuming (i hate that word) that you're using something like dowel points to line it all up (drill one side, insert dowel points, dry assemble and tap to mark) you're going to be pretty close... I'd be tempted to only drill one oversized hole, if possible.. then use something like low tech carpenters glue that has a longer "wiggle" time than the newer glues.. with a glue that has a longer setting time, mixed with a little fine sawdust from your cut, you should be ok..
First off, my question is "why?" My second question is "you haven't done much of this sort of thing have you?" Another one is "what is your goal for working on this instrument?" Actually, what would be MOST helpful would be for you to post some pictures to alt.binaries.pictures.woodworking of the lute. That would make it a lot easier to have a good opinion of what needs to be done. Now, in the pursuit of information...if you are having to reset the neck angle because it has warped from the tension of the strings, it seems to me that there are more problems than just a neck angle. It might well be that the neck itself is damaged or too light, and, in that case, you probably need to look at replacing the entire thing. In any case, I am not sure that your plan will work because I don't think that you can create a strong enough joint to withstand the forces of the sring tension AND dynamic forces of playing. Any joint like this is going to be a weak spot, and will likely be liable to break, especially if you produce a deliberately sloppy hole for the re-enforcing dowels. The only way this might work, having mulled it over a bit, would be to use an epoxy and microbubble mixture. The microbubbles add a chunk of structural support to the glue, and might make it strong enough. Having kind of wandered around, though, I would say that before you did anything, I would suggest talking with a real luthier, who can evaluate both the value of the instrument, and, the best way to restore it. Regards Dave Mundt
Jim T's post over in rec.music.makers.builders titled "Refurbishing an old German lute-guitar (resetting neck & repairing split)" has a lot more info and links to pics, the same post over here might have cleared up some of the confusion (I didn't see it till after I had made the above reply).
At least on a guitar, it's actually a compression joint and doesn't take all that much force to hold it together. Harry Fleishman
formatting link
uses a bolt-on adjustable neck and can actually loosen the bolts and make adjustments while it's strung up to full tension (through an access panel). He could probably glue it up without the dowels and it'd stay put if the mating surfaces were tight.
I ended up using dowels and epoxy, and I'm happy with the result. An experienced luthier whose opinions I respect suggested glue alone would be OK, without the dowels, but I felt dowels would encrease the strength considearably and I'm sure it has. I did a test on some scrap wood first and after that, I knew it would be fine. The joint now looks exactly as before and is probably stronger than before. Luckily the neck was dead straight. It just needed resetting.
Thank you all for the help, advice and suggestions. Much appreciated I can assure you I wasn't trolling, like the hot-headed freak suggested.
The instrument was very beaten up and unplayable when I bought it. Now it is all back together and plays like a dream. I'm happy!
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.