Twocam - Posted - 08/25/2024:  03:59:05

Hi all, 1st post - thanks for join.

I have an old, but barely played FB58. I’m a noob player despite owning it from new!

Trying to set it up properly and I notice the neck joint is poorly fitted - will try and attach some photos. The issue seems to be that the neck touches at the rear of the heel but not evenly along its length and not on the pot ring. Also the fret board is touching the tension loop. That seems to be tilting the neck back.

Any advice on fixing the issue would be much appreciated.

Thanks,
Andy
(Cambridge UK)

schwimbo - Posted - 08/25/2024:  04:21:38

You should first sand or otherwise remove the neck / fingerboard wood that is touching the tension hoop. You can take some coarse sandpaper and wrap it around a wine bottle cork and use this as a sanding device. Try to be careful to not remove the finish from the sides of the neck as you sand the wood (some masking tape on the sides of the neck might help prevent this from happening) You need to remove the neck to sand the area of the fingerboard / neck that touches the tension hoop. As you remove this wood that was making contact with the hoop, check to see if the upper part of the heel is now touching the rim / tone ring. Also check to see how the action is changing (you have to put the neck back on the banjo to see this). If the action was too low before you started taking wood off the end of the neck (where it touched the hoop), then you might get lucky and have the action height change to what you desire, and have contact at the rim and tone ring, and no contact at the tension hoop. However, you might also have to take wood off the lower part of the heel (which would be easier to do if the lag bolt was removed from the heel) if the action becomes too high. You can avoid this if you don't mind using a shim at the upper part of the heel to increase the neck angle (after it was decreased by removing wood from the fingerboard and neck wood directly underneath the board). I have had satisfactory results using the clear hard plastic used to package various things (clamshell containers). You can punch a hole in the plastic and slip it over the upper lag bolt. You might be able to get away with a less wide shim that sits underneath the upper lag bolt, and just makes contact with the neck and rim, but not the tone ring. I think neck contact with the tone ring is not necessary as long as you have good solid contact with the rim at the lower and upper parts of the heel. You also need to check to see if the neck is centered with respect to the tailpiece location, so that the strings don't tend to pull the bridge to the side after they are tightened (which could make the strings off center with respect to the fingerboard). This might mean leaving more wood on one side of the heel, or having a thicker shim on one side of the neck than the other.

Good luck with the project!

Twocam - Posted - 08/25/2024:  07:04:21

Hopefully photos are attached…if so, please excuse dust!

 

Twocam - Posted - 08/25/2024:  07:05:51

Thanks for the comprehensive reply - much appreciated. Time to have a little (careful) fun!

schwimbo - Posted - 08/25/2024:  08:44:20

It looks like you are getting some contact below the tone ring and at the bottom of the heel, though it is not a great fit. I would first get rid of the contact between the tension hoop and neck/fingerboard by doing some sanding. Maybe the tone will improve enough by doing this that you won't worry about the cosmetic aspect of a not so perfect fit of neck to rim.

Some have tried a "quicker" way of sanding the neck/fingerboard (and I used to do this as well) where you just remove (loosen until they are out of the way) the 2 brackets on either side of the neck, loosen the strings and the coordinator rods so that the neck has enough clearance at the rim so that you can slip in some coarse sandpaper between the fingerboard and tension hoop. You can work this back and forth to remove the wood. The sandpaper might put some marks on the tension hoop, so if you are concerned about this, it might be good to put some masking tape over the hoop to keep the metal from being scratched. If you don't care about this cosmetic issue, then it would be one less step. I don't do this method anymore as in bracing the headstock (so that the neck didn't move too much as I sanded), it put more stress than "desired" on the lag bolts, and the lower lag bolt hole stripped - making it necessary to glue in a dowel and redrill the hole for the lag bolt. I just take the neck off when I have to sand stuff.

Twocam - Posted - 08/25/2024:  09:24:37

Thanks. I’ve taken the neck off and am carefully sanding & test fitting with a .002 feeler gauge between the tension hoop and neck/fretboard. Figured a smallish gap is still a gap.

Having fun!

Bart Veerman - Posted - 08/25/2024:  09:29:15

There's enough of the neck contacting the rim for that banjo to sound plenty good enough.

I'd simply leave it as-is and not worry about it.

lightgauge - Posted - 08/25/2024:  09:38:04

While you are there, go for .004 gap. As things settle and with string pressure, it usually closes up a little, in my experience.

Old Hickory - Posted - 08/25/2024:  11:39:23

quote:

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Originally posted by Twocam

Thanks. I’ve taken the neck off and am carefully sanding & test fitting with a .002 feeler gauge between the tension hoop and neck/fretboard. Figured a smallish gap is still a gap.

---

Exactly. A gap is a gap. I agree with the advice to make the gap a bit bigger. Remember: because the neck should be tilted downward relative to the plain of the head, the gap at fretboard level will be a bit larger than it is further down. Also, you need to maintain a gap between the neck and the flesh hoop of the head. If the flesh hoop extends outside the outer face of the tension hoop then you need that much more gap.

Old Hickory - Posted - 08/25/2024:  13:27:24

"plain" of the head?

Really? Oy.

Of course I meant "plane."

Twocam - Posted - 08/26/2024:  05:18:44

Now have a .004” gap between fretboard/neck and tension hoop.


The rear of the neck heel only touches the rim on its back edge via the cap/inlay section. You can see the witness mark in the rim. Heel is cut 90deg at that point. A feeler gauge passes between the wood part of the joint - no contact.

Next step advice much appreciated, please?

(check and set the neck angle, then fit a timber shim to the rear of the heel and sand to a wedge shape that matches heel to rim & closes the gap along its length?)

 

Twocam - Posted - 08/26/2024:  07:47:59

Update: running a straight edge across from nut to bridge with neck bolted as is gives 6mm over fret 12. To get down to 2mm (watching a setup video on YouTube, so please correct me if wrong) requires the neck to be laid back. Should the back of the heel also have a 3deg cut (it’s currently square) to enable this?

lightgauge - Posted - 08/26/2024:  15:24:53

What are you calling "the back of the heel" ?

schwimbo - Posted - 08/26/2024:  16:11:20

To avoid more cutting of the heel, you could put a thick enough shim in the area of the upper lag bolt so that it would increase the neck angle. You could also decide to cut more wood off of the lower part of the heel (near the lower lag bolt) to increase the neck angle). This kind of Fender banjo has way too much wood above the 22nd fret for my taste (it locates the bridge too far out towards the center of the banjo head which results in a more mid-range kind of tone). If you did "major sculpting" to the heel (removing wood at the upper and lower lag bolts - which is easier done if the bolts are removed - and at the fingerboard area), you could reposition the bridge closer to the tailpiece, which in my opinion usually improves the tone of the banjo. However, this is a lot of work. The shim idea is easier, and can at least help to lower the action.

Twocam - Posted - 08/26/2024:  22:18:06

quote:

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Originally posted by lightgauge

What are you calling "the back of the heel" ?

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Furthest away from the head.

lightgauge - Posted - 08/27/2024:  05:17:23

The area around the lower lag should be angled to seat flat against the lower portion of the rim. The goal is solid contact from neck to rim.

Old Hickory - Posted - 08/29/2024:  19:32:31

Stew-Mac sells tapered shims. They're designed for going in the neck pocket of Fender style solid body guitars, but they would work fine for shimming a banjo neck. They're expensive for what they are. But easier than making your own or recutting a neck.