Screw On Neck Reset On Vintage Banjo Mandolin

[Paul Said]

I purchased a "no name" vintage banjo mandolin that requires a neck reset. The instrument did not have a dowel neck attachment and the neck was just screwed to the body. I have read that fitting a shim between the neck and the body i spossibly the easiest solution. My other option is to reshape the neck joint to provide more tilt angle.

What is my best solution?

Regards

Paul

[Paul Breen]

You have a zither banjo, almost certainly of British make. Neck angle is set with the neck heel to pot connection but the wooden pot needs to be held solid between the neck and tailpiece to keep it's shape stable under string pressure. It is common and likely for the pot on this type of banjo construction to warp into an oval at a right angle to the strings and there-by raising the string action. The drop in tone ring assembly should have an adjustment screw or other strategy at the tailpiece and neck ends to bear against pot and hopefully keep it round. Your banjo may not need a neck re-set at all and the action issues could be from this common problem with Zither banjos. The neck connection on your banjo could be shimmed but re-shaping the neck heel for a good fit is best.

In this image, on the top left ring, can be seen a machine bolt coming out of one side and a threaded hole for another at 180 degrees that was missing. One bears against the neck from inside of the pot and the other against the tailpiece.

The tone ring assembly mounting brackets are not enough by themselves to keep the pot round, seen here...

These images are from a mandolin banjo and it was a pain in the a** to get it playing as good as it could. This instrument is very bright, bordering on ear piercing. You  may want to consider setting it up as a 4 string mandolin or as a ukulele with plastic strings. Both alternatives would reduce problematic string tension. Hope this helps...

[Paul Said]

Thank you for you response. There is an adjustable machine bolt facing the neck but not on the tail end of the ring assembly. The machine bolt head was not resting against the pot when the ring assembly is in place so l suppose l should adjust this  as a first step.

I also have a suspicion that the strings gauge may have been too heavy for this instrument. There was an old set of spare strings in the case and the no 11 was stamped on the back of the box. I'II chase up some lighter gauge string as well. Thanks again.

Paul.

[Allen L Wall]

Being a banjo player it seems like some kind of dowel down the center inside the pot in line with the neck would help when the strings art tuned up. I know this would violate the "prime directive", but just a suggestion.

[Paul Breen]

Might be possible to add a rod but there is limited space below the tone ring assembly.

These are just not very well designed instruments for 8 strings of tension. The best banjo mandolins are heavy built, 11" wood rim instruments. Even those suffer from a lot of overtones. Stuffing a towel or sock or the like in it helps and so does getting rid of 4 strings and setting them up with only 4 strings, A.K.A. Tango banjo. You won't see many of these out at jams...