banjonz - Posted - 01/02/2025:  14:53:41

I have a cheapy Asian banjo for repair. It has had the usual "fall off something" and cracked the neck. It hasn't broken it and is still appears structurally sound.
My approach would be to see if I can open the cracks a wee bit and squirt in thin CA glue. What do you think?

Owen - Posted - 01/02/2025:  15:03:27

I've never repaired a banjo neck, so I say without reservation, "Go for it!"   

Fwiw, when I glue cracks, where it's feasible, I like to get out the ol' 3/8" Black & Decker and augment it with dowels across the crack.

mrbook - Posted - 01/02/2025:  15:47:43

Use original Titebond or hide glue, not CA glue, epoxy, or Gorilla glue.

wtalley - Posted - 01/02/2025:  16:01:23

Thin CA glue will wick into the tightest of cracks. In fact, you should clamp the crack and then apply the glue. It will wick right into the crack. Keep applying the glue until it stops wicking into the crack. Wipe off the excess with either acetone or debonder. Personally, I have no reservations about using CA glue on any part of a banjo that a repair person would not have to take apart.

notty pine - Posted - 01/02/2025:  16:43:36

Just be careful not to get glue in the trussrod channel.

banjoT1 - Posted - 01/02/2025:  17:52:29

IMO...on the one hand the break is easy to repair - but then, on the other hand, there is a very critical issue you've got to experiment with before you dive in.

But first, again IMO, the successful outcome is largely dependent on your workmanlike attitude, patience and pre-planning. And, even though you label the banjo as an "Asian cheapy" it offers you an excellent learning opportunity that others could only have wished for.

Remember...details, details.

a) the good thing:
...obviously the break is not a "complete" break, meaning that the parts and wood fibers remain in relatively good alignment. This matters because there be less to no lateral parts slippage as you gingerly apply clamping pressure (after inserting glue).

b) the bad thing:
...unlike other break possibilities where pieces must be fit together as a puzzle, your situation makes it difficult to apply the glue into all the necessary nooks and crannies.

c) the experiment:
...using wood scrap pieces you'll need to settle on a thin or thinned-out adhesive/glue that when injected into the break will flow quickly but without setting up too fast. Other folks may have certain CA glue recommendations but from my experience I would experiment with a water-soluble glue that you've thinned out so it flows and properly wets all wood fibers (the judicious use of extra water will help do that).

d) the big deal:
to prepare for clamping...one properly padded c-clamp should be sufficient. Don't over tighten. A little squeeze-out is good. Sit next to it for 20 minutes ..... then with a very sharp chisel you can pare off the moderately hardened-up squeeze out but if you set it aside the neck for say, a day, then cleanup will be exponentially more difficult. Work around the clamp but DO NOT remove it earlier than 24 hours.

e) the result:
hopefully you've done good up to now. Now proceed to finish touch-ups. Don't fuss too much or you'll create unnecessary problems. Rather, a very light smear of matching shoe polish on your fingertip will help to 'invisilize' the break line. Most felt markers for example, are not UV fade proof.

f) atta-boys:
...show us your victory.

Fathand - Posted - 01/02/2025:  17:56:52

I have trouble sometimes getting CA glue to stick wood to wood.



I have successfully repaired at least 4 broken guitar and banjo neck breaks, including one banjo neck in 5 pieces. I have used original Titebond for all of them. I do not thin it. 



You can sometimes get the titebond in there by drawing through with dental floss or strong (sailmakers) thread. Blow through with air, or I have heard of sucking it through with a suction cup (not tried).

Clamp well, practise dry clamping first. I have used a vise if it fit.



Titebond has the added advantage of being water soluble and can be damp wiped off before dry without damaging the finish usually. CA eats nitro in my experience.

Edited by - Fathand on 01/02/2025 18:03:35

banjoT1 - Posted - 01/02/2025:  18:15:05

...yes, everything Fathand above sez.



Thermoplastic adhesives/glues (such as the water solubles) tolerate disturbances of their molecular chain and cross-linking during clamp and handling farting-around, set up and 'drying' but thermo and other chemical-set molecular chains do not.



...wicking, yes, is very important - that's why IMO, soluble glue experimentation is necessary for YOUR situation.

Edited by - banjoT1 on 01/02/2025 18:19:49

martyjoe - Posted - 01/02/2025:  22:02:55

Using bicycle tubing tightly wrapped around the neck makes a very good and even clamping force. Making an awkward job simple.

 

sunburst - Posted - 01/03/2025:  08:08:09

The wicking property of CA makes it tempting in situations like this, but I prefer the tried-and-true strength of hot hide glue. Hide glue can also be wicked deep into cracks like this if the wood is warmed to above the temperature at which hide glue gels. Slowly and gently heat the neck until it is above about 90 degrees F, add a touch more water to the glue to thin it slightly and keep everything warm while working the glue into the crack. Clamp and let it cool for as long as it takes. I would leave it clamped overnight at least.

banjoT1 - Posted - 01/03/2025:  11:25:37

...furthermore Mr. BanjoNZ, you mentioned that you might even try to "open the cracks a wee bit. Here's my O on that:

a) good idea but when doing so (ie., prying the break to open up a bit) is sorta like poking your finger in the eye of potential mayhem and heartbreak.

b) with much trepidation, a brain surgeon's touch, and keen awareness of what you're doing, you MIGHT be able to leverage open the break just enough to give additional working space in order to stuff adhesive in and around those hard to reach nooks and crannies. BUT, I would only do so - NOT by hand-leveraging it open....that method is too uncontrollable. Rather, you could rig up on your workbench a method that clamps/holds firm, the peghead (neck upside down), then with a very, very light pull down at the heel you would like see the crack/break open up a bit. The pulling down at the heel could be done tourniquet style - this gives you control to a safe stopping point that would allow then for hands free glue application. Dicey ? Maybe yes, maybe no - depending on how Zen-careful you are and your understanding of the physical properties of the neck's wood fiber flex.

...but then, within the last day you may have repaired it by now. (??)

banjonz - Posted - 01/03/2025:  11:29:17

Thankyou for all advice given. It gives me plenty to consider the best approach. I am thinking towards thinned titebond. What would be the ratio of thinning 50/50?
Also what would be the finish on these banjos? Catalyzed polyester or something else?

banjoT1 - Posted - 01/03/2025:  14:04:23

...well, to answer these sorts of questions that's why it's necessary to experiment. For example, if possible, using as closely similar wood scrap material, create a partial break, then open the break a "wee bit" to get a "feel" of glue consistency you need and "feel " of the procedure.



Without the benefit of videos here, and sorry if this sounds preachy, but there are no scientific or shop manuals to follow...rather, your visualization and execution of the repair falls into the heading of "Luthiery Arts" or "Journeyman Woodworking" - competency levels achieved by many prior failed attempts and costly re-works.



And no, IMO your suggested 50/50 mix is waaay to thinned out. I would experiment by squeezing out say, 2 tablespoons of glue on a plastic palette then using a coffee stir stick-type thing, drip in several water drops, then stir. Then go "...hmmmmm". Repeat until the mix has good flow but not watery. Next, while still working swiftly through all of this (so your stir mix doesn't dry up) next, with a 1/16th " bamboo shiskeebob skewer, stuff the glue into the simulated break...step back, purse your lips then say "....hmmmmmm" again.

Now, repeat your recipe but in the quantity you need. Remember....once you decide what you think will work - proceed. Have all necessary accoutrements, tools, clamps, rags, tape, etc., on the ready close at hand.



Next...proceed accordingly, either:

a) launch yourself into the dark abyss of doubt (like... "should I really marry her ?") or,

b) whistle while you work - with certainty of expected outcome.



And also remember, if you screw up it's almost non-repairable but, if you understand why, and promise not to do it again, then you can help the next guy.

Likely the finish is a pre-catalyzed lacquer for speedy set-up and quick cure - but other folks might offer better info. 

Edited by - banjoT1 on 01/03/2025 14:21:14

banjonz - Posted - 01/04/2025:  11:34:50

Thankyou for all your input. I decided to use ultra strong aliphatic glue which I was able to force into the major crack by opening it a bit then applying glue with a 0.02" feeler gauge. I did this a number of times to ensure deep penetration. I left it clamped over night then using CA glue with a pipette, I wicked along the other cracks a few times. It looks like it worked. All that is left is refinishing.

banjoT1 - Posted - 01/04/2025:  20:04:15

Other than our preference for something NOT broken, those things "pre-owned", "repaired" or "refurbished" typically are worth less, i.e., less desirable, less priced, etc. However, although there's a severity range of neck breaks - from "hairline crack" to "splinters", let's take your break for example banjoNZ; I'm not so sure that your good repair would negatively affect the output of your Asian banjo, nor for that matter would a good peghead/volute repair affect the acoustics of say, a $5,000 banjo.

This is theoretical only cuz I've never come across any acoustical test reports about this sort of thing nor do I recall any relevant postings here on BH.

So, any reliable data out there?? Of course there's anecdotes, perceptions, and opinions but I'm enquiring about actual data.

If not then we could say, theoretically, that a good repair of a fixable peghead/volute break would likely not affect a banjo's SOUND characteristics.

...yes, no, links ??

sunburst - Posted - 01/05/2025:  10:06:33

No links, but there is scientifically derived info in the literature. Some can be found with an internet search.
Guitars, mandolins, banjos and others are similar in that the real work of making sound is done at the body of the instrument. Plate modes of motion, air mode of motion, coupling of oscillators and so forth. Necks are mostly involved in full body bending modes, and in most hand held stringed instruments the lower ones of those are lower in frequency than any notes played on the instrument, so there is little affect on sound and can petty much be considered negligible. Higher ones don't seem to make much difference. (Electric basses can be an exception.)
So, when we understand the basics (that's all we need and for the most part, all I really understand about it) of how acoustic instruments produce sound we can realize that little thought needs to be invested into how a repaired peghead break will affect sound and move on to the structural aspects.

Bart Veerman - Posted - 01/05/2025:  12:08:59

I've never needed to glue a neck but I've fixed a couple of cracked chair legs with great results. I can imagine this stuff doing a good job on necks. Talk about wicking in real good and the glued kitchen chair leg holding up real good to hefty guests:

leevalley.com/en-ca/shop/tools...ctor-glue

Edited by - Bart Veerman on 01/05/2025 12:24:36

banjonz - Posted - 01/05/2025:  14:48:17

quote:

---

Originally posted by Bart Veerman

I've never needed to glue a neck but I've fixed a couple of cracked chair legs with great results. I can imagine this stuff doing a good job on necks. Talk about wicking in real good and the glued kitchen chair leg holding up real good to hefty guests:

leevalley.com/en-ca/shop/tools...ctor-glue

Thanks Bart. There is a supplier here that sells it. I do however have syringes with a whole selection of different needles and have tried using my glue to inject into cracks. It was quite a while ago and I cannot remember the outcomes. I must retry it. Thanks again,

---

Dan Gellert - Posted - 01/05/2025:  17:23:44

A suction cup can help push/pull glue into a crack, though it might be tricky to find one of the right size and flexibility to work on that curved surface.

sunburst - Posted - 01/05/2025:  20:18:49

To help glue penetrate a crack one can simply put one's mouth over the area and blow glue in. A mouth can fit better than a suction cup.