to start took a chunk of aluminum and cut it to size, then i drilled the hole for the spool to ride in and the ports for the air source and pilot of a piston valve to screw into. the finished body
<a href="http://s696.photobucket.com/albums/vv32 ... 0_0147.jpg" target="_blank"><img src="http://i696.photobucket.com/albums/vv32 ... 0_0147.jpg" border="0" alt="Photobucket"></a>
and
<a href="http://s696.photobucket.com/albums/vv32 ... 0_0148.jpg" target="_blank"><img src="http://i696.photobucket.com/albums/vv32 ... 0_0148.jpg" border="0" alt="Photobucket"></a>
then for the spool i took a steel rod and shaped it on the drill press. then i made my own seals out of a rubber sheet. that right, no boughten orings for me 8)
the spool with spring removed
<a href="http://s696.photobucket.com/albums/vv32 ... 0_0150.jpg" target="_blank"><img src="http://i696.photobucket.com/albums/vv32 ... 0_0150.jpg" border="0" alt="Photobucket"></a>
and i connected it to small piston valve to test the semi auto
<a href="http://s696.photobucket.com/albums/vv32 ... 0_0145.jpg" target="_blank"><img src="http://i696.photobucket.com/albums/vv32 ... 0_0145.jpg" border="0" alt="Photobucket"></a>
and with a fire extinguisher as a 400psi air tank for it
<a href="http://s696.photobucket.com/albums/vv32 ... 0_0144.jpg" target="_blank"><img src="http://i696.photobucket.com/albums/vv32 ... 0_0144.jpg" border="0" alt="Photobucket"></a>
i made it with all hand tools and only 2 powertools, a drillpress and grinder.
it works perfectly for semi auto and with that tank i can get alot of shots.
the only problem is that the chamber on the piston valve gets hot with continuous fire...



