Pipe Rackboard Gauge
by Randy A. Bergum
copyright July 1998
A while ago I built a small pipe display rack for our church in Fullerton in order to raise funds for the New
Organ Fund.
Not having all the tools needed to finish the job, naturally I borrowed what I could. Bob Trousdale lent me a pipe
toe gauge that worked marvelously for this job. This tool allows you to determine the diameter of each pipe toe
at the point where it passes through the rack board on a pipe chest, and these numbers are used in the construction
of the new rack board. The spacing between the rack and the toe board on most chests is 4-1/2", which seems
to be what Wurlitzer used in their chest work. After the display rack was finished, it was time to build a gauge
for myself!
This design was shamelessly stolen from Bob Trousdale, once again proving that he does things the right way. The
gauge was constructed out of wood scraps on hand, the top being 1/2" birch plywood, which is very stable.
The bottom is ash, which was two pieces of 6" wide stock biscuit-joined together for warp resistance, and
the sides are basswood.
I like durable tools, so the wood was finished in satin lacquer for stain resistance. Dimension sizes for each
hole were printed and laminated in plastic, and since my eyes are getting fuzzier these days, a larger type size
was used to aid in easy reading.
The layout work was designed on the computer to get the hole spacing just right, and a plot produced that called
out each dimension from a fixed datum, usually an edge. The layout and drilling of the holes took less time than
the designing (ain't that always the way!).
The rack board and the base were clamped together to eliminate any errors in registration, then all marks were
laid out and 1/8" pilot holes were drilled in both boards together. Most holes were bored with forstner bits,
but bits in the larger sizes are really expensive, so the bigger holes were bored using a trepanning tool chucked
up in a mill/drill. The use of a scrap backing board minimizes tearout on the back side of the rack board.
The toe holes range in size from 1/4" to 2-1/2" diameter. If anyone has run into a pipe bigger or smaller
than this, let's hear about it!
Fig. 1 - The Pipe Gauge
Pipe Toe Hole |
Width of C'sink |
Diam. of Toe hole |
1/4" |
.625" |
.250" |
5/16" |
.625" |
.250" |
3/8" |
.625" |
.250" |
7/16" |
.625" |
.250" |
1/2" |
.625" |
.250" |
9/16" |
.625" |
.250" |
5/8" |
.625" |
.3125" |
11/16" |
.625" |
.3125" |
3/4" |
.625" |
.3125" |
13/16" |
.625" |
.3125" |
7/8" |
.625" |
.3125" |
15/16" |
.850" |
.4375" |
1" |
.850" |
.4375" |
1-1/16" |
.850" |
.4375" |
1-1/8" |
.850" |
.4375" |
1-3/16" |
.850" |
.4375" |
1-1/4" |
.850" |
.4375" |
1-5/16" |
.850" |
.4375" |
1-3/8" |
.980" |
.500" |
1-7/16" |
.980" |
.500" |
1-1/2" |
.980" |
.500" |
1-9/16" |
.980" |
.500" |
1-5/8" |
.980" |
.500" |
1-11/16" |
.980" |
.500" |
1-3/4" |
.980" |
.500" |
1-13/16" |
.980" |
.500" |
1-7/8" |
1-1/4" |
.625" |
1-15/16" |
1-1/4" |
.625" |
2" |
1-1/4" |
.625" |
2-1/16" |
1-1/4" |
.625" |
2-1/8" |
1-1/4" |
.625" |
2-3/16" |
1-1/4" |
.625" |
2-1/4" |
1-1/4" |
.625" |
2-5/16" |
1-1/4" |
.625" |
2-3/8" |
1-1/4" |
.625" |
2-7/16" |
1-1/4" |
.625" |
2-1/2" |
1-1/4" |
.625" |
Fig 2. Hole and Countersink Sizes