I just bought a Stew-Mac archtop a few weeks ago and really love the sound of this particular banjo. The banjo is endearing with some manufacturer quirks (the inlays aren't quite linear and there are no evident truss rods) but the back of the neck is consistently a bit sticky. I have wiped it down and rubbed it and was hoping playing would help to clear whatever is back there but to no avail. There is no obvious residue or debris and the finish is not tacky except for the posterior aspect of the neck where my thumb/thumb webspace makes contact. Any advice as to safely cleaning or treating without having to sand and re-finish?
It is not a shiny lacquer-type finish. How would I discern oil versus varnish versus lacquer other than shiny versus non-shiny? The banjo was a kit from the mid-70s. The Minn-Wax theory sounds plausible..... I'll try the Stew-Mac # also.
You could try putting a little solvent on a rag and wiping the sticky part. You can tell the type of finish by how it reacts to different solvents. For example, if you use alcohol and any color comes off on the rag, then the finish is probably shellac. If you use lacquer thinner and you get any color, the finish is lacquer. if you use mineral spirits and get some color, you have got something else... The objective is to try this on a small area, use a little bit of solvent, don't rub too hard, and see if you get a little color on the rag. You will at least know what you are dealing with then.
You also might try some 0000 steel wool, just on the sticky part. Be careful with that, though. If it is real gummy you might end up having to strip it all off.