Upton Bass: Prescott Restoration

"Prescott" Double Bass, c1830

Every pet owning bass players worst nightmare! Dog hits bass A, knocking it over. Bass A hits bass B. Bass A's scroll ear smashes into bass B's upper ribs. Bass A (German factory bass) is fine while bass B (1830's "Prescott") takes a ride to our Mystic, CT shop to repair the damage.

In repair page one we repaired a smaller rib hole/crack very successfully. This is a much larger hole, but it will blend quite nicely. All the pieces were there and went together without too much convincing. A maple veneer along the inside will give all the support it needs. Touch-up was a bit of work mainly because we had to make our existing varnish opaque to match the surrounding varnish.

The real problem is the scroll. Upon first inspection it was deemed by us to be unstable. The owner bought this bass 18 years ago and noted the cracks and brass pins, so he put some pencil lines to see if the cracks would travel. Eighteen years later, the pencil lines show the cracks have not traveled. But when we took off the plate tuners, everything just started falling apart! It is a miracle that 1) this scroll was not buzzing beyond belief in the owners ear and 2) the scroll has not just snapped off! This neck and scroll though are what we call "Frankensteined" together. The neck length was shortened by way of a lap joint and hardware. The neck heel had been lengthened to ad more over stand. The fingerboard had been reverse shimmed to decrease the projection. The neck heel has been shoe'd twice in attempts to raise the projection. The neck set mortise is very shallow and only lag bolts hold it into the block.

Obviously years of repairmen have brought this neck back and forth. It is time for a new neck and scroll graft!

We x-rayed the scroll to see just what we were in for. About 35 nails will need to be removed before we start to carve, if we go that route. There are two possible repair route's to take:

#1)The scroll will need 8 bushings and cheek grafts. The inner wood of the peg box walls will be replaced with the neck graft, and the outer portions of the peg box walls will be replaced with the cheek grafts. Just a thin amount of original wood will remain in the middle (although most of this wood will be bushings). In the end the scroll will have maintained our goal of conservation of original material when allowable.

#2)The volute will be grafted onto a new neck & peg-box.

Our goal is always the preservation of original material. Even though this scroll shows much evidence of not being original to the maker, we decided to preserve the story it tells, and have elected to proceed with repair route #1.

The string length is currently set at 42.5" and we shortened it a bit to 42". The projection is about 7 inches and that too will remain. The over stand is currently 6.5mm (this is spec for a violin, not a bass) and that will be corrected to 25mm. This will change the angle of the strings over the bridge and thus reduce some of the string tension on the top, as well as make for a more comfortable playing instrument. A new neck block will allow us to set the neck deeper, thus adding the strength to the mortise that is needed so that the lag bolts can be abandoned. Originally the peg-box walls were too thin at the base and were not load supported by the neck. This caused the peg-box to crack along the floor. The scroll graft will allow us to carve thicker peg-box walls that (inside edge) extend into the neck. This will put the load of the peg-box walls onto the whole of the neck and help to prevent future failure.

At the last minute we decided not to install the original tuners back on the bass (they were brittle and had as many repairs and patches as the scroll had). Not enough time (and money) were left, so standard German plate tuners were installed with an offset orientation to take some pressure off the scroll.

The bass finished out very well and was out to gig with the owner the first day it was picked up!

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