SET UP.
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B
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D
E
F
MATERIALS
For metal parts, you can use steel,
aluminum, brass, or copper, depending
on what’s available and what kind of look
and feel you want.
Century Spring (
centuryspring.com),
or similar size and spring constant
» Coil spring, about 1" long like from
a click pen, printer, scanner, toy,
or similar — for trigger return
» Coil spring, about ½" long like
from a printer, scanner, or disposable
lighter — for catch mechanism
A. Plastic Pipe
» PVC pipe, Schedule 40,
1¼" ID × 1' length
» PVC or HDPE pipe, Schedule 80,
½" ID × 6"
E. O-rings and clips
» O-rings, rubber, 11" OD,
4" ID ( 2)
» C-clips, 1" ID ( 2) aka external retaining rings or “circlips”, to fit your barrel
B. U-channel stock, aluminum,
1.5mm thick × 22mm base × 12mm
legs, 1' length or
5"×
4"×½"
» Fender washer, 8mm ID × 32mm OD
» Bolt, 6mm
» Machine screws, 3mm ( 7)
» Screws, self-tapping, short ( 7) Mine
had 7mm threads, 10mm total length.
» Screws, self-tapping, long ( 2) Mine
had 18mm threads, 22mm length.
» Screw, short and wide for holding
the plunger onto the rod. I used a
bookbinding screw.
» Metal, assorted scraps
for machining small parts. I made
a 10mm-thick aluminum trigger, a
16mm (
3") cylindrical steel insert for
the handgrip, a ½" round piston stop
from scrap brass sheet, and a
6"
internal stop from a scrap of steel.
Gregory Hayes
C. Metal tubes and rods
» Tube, metal, 1" OD × 1' Different pipe
diameters will work for the barrel, but
you’ll have to adapt them differently
to fit the dart.
» Tube, metal,
7" OD × 1'
» Rod, metal,
1"× 1' like from an old
printer or scanner
» Rod, metal,
7" diameter, a few
inches long or similar stock, for
machining the catch piece and
the rear stop
D. Springs
» Compression spring, 0.7" diameter
× 6" long, 6.2lbs/in item #364 from
» Metal strips, Q" (0.015") thick
× ¼" × 4" to attach the trigger return
spring to the trigger
» Aluminum flat bar, 3mm×20mm× 1'
length for the trigger plate
» Aluminum flat bar or sheet,
1mm×20mm× 1' length for the
trigger ramp and trigger guard
» Pull ring, about 1" ID big enough to
put a finger through
» Music wire, 1.58mm (0.062"), about
1' length You need 4", but expect
some trial and error.
» Cutting board, plastic, ½" or
thicker
» Wood scrap, about 1" thick enough
to make a pistol grip
» Acrylic scrap, ¼" thick enough to
cover both sides of grip
TOOLS
F. Metal lathe
» Soldering torch and solder I used
a little butane blowtorch, about the
thickness of a marker, that I got from
my local auto parts store.
» Drill and drill bits
» Countersinking bit
» Taps: 3mm, 6mm
» Files, small
» Hacksaw, screwdriver, pliers, ruler,
and pencil
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