Archive for category: Repair and Restoration

EXTREME neck repair

19 Dec
December 19, 2013

Have a lot of time on your hands? Of course not, and neither do we.  But sometimes it’s fun to go nuts.  I know that many shops would recommend simply replacing a neck when you have damage to the neck heel like this. But the truth is that just anything can be fixed.  Plus  when faced with the bill,  the public school that owns this bass  would likely put this instrument out of commission rather than replace a neck.  In Wisconsin, before close to one billion dollars was taken out of the public school system in 2010 I didn’t think things could have gotten worse.  We know better now. At least those responsible for that move can proudly  point to their Tea Party inspired fiscal policies and say – “see, I told you  charitable giving would make up the difference!”

This  Engelhardt came to us with not only two cracks in the neck heel but the male part of the dovetail was sheared off as well.  With a pocket and  insert it’s possible to kill two birds with one stone – reinforce the breaks and come up with a new dovetail tenon. It’s easier when you can do this without the fingerboard attached because then you can use a router or table saw to hog out much of the waste. But here we used drills and chisels to make a straight sided but tapered pocket as big and deep as we dared to go, using little die makers squares to try and keep things squared up.

If you can manage to keep the pocket  more or less square then fitting an insert isn’t that bad.  Yes, I know that the blind back wall is a stress riser that may contribute to a future crack but the back corners do incorporate  a large corner radius, plus that part of the neck heel is thick.  The Kay/Engelhardt basses are ideal for this type of reinforcing spline because the grain of the wood is going the same way as the spline.


blockless neck conversion and restoration

23 Jul
July 23, 2013

This was a demanding project involving a large South German bass with “blockless” construction and an integral bass bar.  The bass was in rough shape and had suffered through many of the typical amateur repairs.

First we started with the top, repairing all the top cracks, then we planed out the integral bass bar and judiciously took out extra material in that area until both sides of the top were symmetrical. A bass bar was fitted,  edges replaced to widen the top and the table edge was patched with half edging all around to reinforce  the new edge replacement and correct the use of wood putty that was used to fill in craters around the plate edge.

For the back, the button area was glued together using the aid of a plaster mold, and an inlayed patch reinforced the break. Then the ribs in the upper bout were joined to the back again and a spruce neck block was fitted and glued in.

Someone had inexplicably  used a rasp to work down the ribs so we built up the rib height in the lower bouts with bent quartersawn maple stock,  joined with a simple square edge joint.  That was reinforced with new inside lining.  Also,  rib height was added in the C bouts due to sagging and large doubled rib patches were removed, allowing for reinforcement of the rib cracks with small cleats and linen strips.

Before the top was glued on we decided on a final string length, neck overstand, angle and bridge height.  The string length was taken down from an impossibly long 44 3/16″ to 42″.  A new German machined carved neck was installed (the original scroll was unusable) and finally we finished things up with the setup and varnishing.

top reforming

28 Dec
December 28, 2012

A German “shop bass” came to us where the top was badly sunken and cracked  around the sound post area.  After opening the bass it was clear the the top had been regraduated at some point and had been thinned too much in the area around the F holes.  So after stabilizing cracks we started with a partial plaster cast of this area to help  reshape the top.   The work involves removing the bass bar, thinning the top where you want to make changes, “correcting” the mold to give you the shape you want, then pressing hot sand bags into the top as it sits in the mold.

After we pushed the top back to the original curvature we prepared a large bed for a “belly patch”  and fit the reinforcing spruce patch into place.  This new wood stabilizes the shape, reinforced numerous cracks in the area and allowed us to thicken up the top plate a bit where over thinning had weakened it. After this work was done we could move on to other repairs on this bass.

A complicated job – really more of a “restoration” than a repair.  To all my customers patiently waiting on me to finish up big projects – please bear with me. These projects have a way of getting out of hand!

new tuning machine spindles

16 Nov
November 16, 2012

The tuning machine spindles on this Eastern European made bass were made from soft die cast zinc and the driven end eventually deformed.  We made some new ones from hard wearing stainless steel and this little project was a good excuse to use the lathe and milling machine we have here.

New neck for a Kay bass

28 Apr
April 28, 2012

We installed a new Engelhardt neck on a nice Kay bass from the Forties. You can get the new neck without the dovetail precut which allows you to get a tighter fit in the old mortise. In this case we increased the neck angle and overstand for better neck projection.

French Style Scroll Graft

28 Apr
April 28, 2012

Here are some shots of a new neck we installed on a nice old Tyrolean bass.

Originally “blockless”.

Center seam insert

28 Apr
April 28, 2012

Older flat back basses often  need an insert to restore the original width of the back.


Carbon fiber neck reinforcement

28 Apr
April 28, 2012

Here’s one way of stiffening the thin neck of a  bass – using a carbon graphite bar.  Shown is the routing setup post cut, the carbon rod and the maple filler strip that goes over the top.

Doubling the button

28 Apr
April 28, 2012

This nice Romanian bass suffered a blow to the neck and as a result the  button broke from the back and stayed with the neck heel.  The repair involved reattaching the button, then removing the back. Then we prepared the broken area for a patch and fit one in. The bass was then reassembled, the neck reset and the varnish touched up. The final image in the set is of another bass where we did a similar repair.


New Bass Bar

28 Apr
April 28, 2012

We installed a new bass bar for a smaller German shop bass. The bass had cracks right along the  bar at the top and bottom of the plate so we decided to reinforce the glued cracks with egg patches and fit the bar over them.

While the top was off we also replaced some ragged plate edges, patched in spruce around the upper and lower block areas and  fit half – edging all around.