Sanding Bridges

Tcoates@aol.com Tcoates@aol.com
Sun, 06 Apr 1997 12:31:35 -0400 (EDT)


<<Tim,

   I haven't had a chance to look for the article yet, so in the meantime,
do you do this sanding by hand or with something like a finishing sander?
I have several of those 'L's coming up here, so I'm just gathering
information. Thanks.

Avery>>

Hi Avery,

Sand by hand using a sanding block and 120 grit.  Be careful to keep it
level.  Just sand enough to remove the grooves.  Many times the bridge pins
aren't in the correct spot.  So, renotching is done next.  Use the longer
bridge pins with the one end pointed.  Insert about ten unisons of pins at a
time.  Put one drop of Epoxy (West Systems best) on tip of pin before driving
in with tack hammer.  You can hear it hit bottom.  Use laquer thinner to
clean up excess epoxy (covers top/notch and seals them).  Tooth brush works
well for this.  Let epoxy dry overnight.  Use belt sander with 80 grit belt
to level pins (don't worry about heat, doesn't happen if you constantly
move).  Debur with nylon brush.  Lub with DAG.  Takes about 4 hours.

I find doing this before any soundboard work is best.  The gray dust from the
leveling of pins gets into exposed soundboard wood (I don't care how careful
you are, it still happens.)  The epoxy can also make little spatters on the
board.  So guard against that if you aren't repairing/refinishing the board.
 If you don't like using epoxy on bridges I suppose you could do without.
 But it does help fill hairline cracks.  A 100 watt solder gun will release
the epoxy if you need to get epoxed pins out.  The bridges can be
taped/sealed with duct tape while the soundboard is being repaired (dried
down).  Duct Tape (Is Red Green on this listserve?) keeps the bridges from
being affected by the drying down process.  Also helps from getting knuckles
skinned  <g>.  The heat from a hair drier will release the adhesive when
removing the tape.

This is all off the top of my head, as the Spurlock article is at my shop
library.

Tim Coates
University of South Dakota




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