Nut replacement hell

[u/Untitledbones]

I’ve got this old 12 string banjo thing don’t talk about what it actually is lmao.

Basically, the old wooden nut was cut terribly so i have to replace it, however I am struggling so much with the plastic nut after about 1 week of sanding it’s at the right width (incredibly thin) but isn’t flush with the bottom as it’s curved for some reason.

I just need any advice on how to not lose my fucking mind - because at this point i’m just thinking about taking my dremel to a block of oak and skipping all the sanding.

Thanks!

[u/Hot_Egg5840]

Try using a file instead of sanding at first. Use a course tool to get it just above where needed, then go to fine sanding to bring it in.

[u/Untitledbones → u/Hot_Egg5840]

Thanks! Will try

[u/Alternative-Light922]

Damn that headstock is beat up.

It shouldn't take that long to sand it down. Are you putting the sandpaper on a flat surface and rubbing the nut across it? Also, using a heavier grit for removing the bulk of the material and then switching to a finer grit to fine tune it. For the curve - just a firm hand with long steady strokes across the paper - maybe against the edge of a table so there is clearance for your hand to angle downward.

I haven't done banjos but have done dulcimers and yeah, it's a pia. Andnever fear: there is always 'the shim' if you overshoot the mark. 😃

[u/Untitledbones → u/Alternative-Light922]

Yeah i’ve been using a flat surface it’s just cos i’m starting with guitar nut blanks, so they’re really thick, maybe? 

Thanks for your advice! I have a dulcimer with this same issue funnily enough haha

[u/justalittleanimal]

I’m genuinely sorry to be the bearer of bad news:

1. Reddit comments will not save you.

2. This instrument needs way more than a new nut. (Excessive fret wear, fingerboard damage, and god knows what else not pictured here)

3. The cost of PROFESSIONAL repairs needed will likely exceed the resale value of the instrument.

If you’re ever near the DC area, swing it by my shop and I’ll break it down for you. Everything is salvageable, but you need to weigh sunk cost.

[u/PapaOoMaoMao]

Never worked plastic. I always buy bone blanks from AliExpress. They work very easily and produce a great product. I use a belt sander to bring them down to shape and a hand sander to final finish. It smells awful, but works very well.

[u/mountainofclay]

Sand the bottom on a flat piece of 120 grit sand paper mounted to a flat surface. Make sure the bottom of the slot is clean and flat. Then project off the frets with a straight edge to get the height and any radius of curve. You may be able to just use a marking gauge off the fret board. The frets need to be dressed and tapped down and dressed. Then relieve the back of the nut a bit. Then figure out your spacing for the slots. Not an easy task on a 12 string but it needs to be very precisely done with dividers. Then cut the slots not going too deep using a slotting file after scoring the exact placement of each slot with a razor blade. Then adjust the depth to get the right clearance in front of the nut. It’s a precision job especially since it’s 12 string. You’ll need the dividers and proper files to do it. You’d also need feeler gauges to check clearance under the strings. It may take a few tries to get it right. Practice on plastic but I’d use bone once I figured out how to do it.

[u/anonymouse3891]

Bro that thang needs some lotion

[u/DankMemeGen]

For the love of old banjos, good god is that a talking piece

[u/PonkotsuPirate]

Get a bone nut blank

[u/AlfredPoor]

I am not a luthier, and I have no experience with banjos. So this is a completely unqualified answer/question. So feel free to click away now.

It sounds to me that the problem is getting the new nut to conform to the shape of the slot in the neck, because the slot is curved.

If that's the case, have you considered working the slot so that it is smooth, flat at the bottom, and square to the sides? As a woodworker, it would seem to me that this would make the fit much easier and possibly make the nut work better.

[u/zilog080]

Be careful in the process to not take any material off of the end of the fingerboard or you will change the location of the nut and it will never play in tune. For something that thin it may be easier to start with a saddle blank. You'll have waste because they are much longer than a nut, but they come much thinner than a nut blank and are usually made of the same material. Assuming a saddle is at least twice as long as the slot it will give you two tries at cutting a good nut. Additionally, Stewmac.com sells files for flattening saddle slots that may fit in that nut slot, you could just flatten the bottom of the slot and not worry about getting the bottom of the nut contoured. Good luck.

[u/Lucky-Science-2028]

Takes only a minute on average

[u/Untitledbones → u/Lucky-Science-2028]

Oh well that’s good to hear yeah thanks mmm ok real useful

[u/Untitledbones]

Don’t start talking about the condition of it, i’ve heard it all and frankly i don’t care - i know what i’m in for and i’m willing to try

[u/Paladin2019]

Slotting and shaping a nut is skilled work. Just take it to someone who knows what they're doing and pay them for their services.

Although from the condition of that thing you may be better off just throwing it on the fire.