Brobdingnagian Bertha (Giant Fiberglass cannon)
Posted: Mon Jan 08, 2007 1:49 am
This cannon is constructed of appox 8 feet of 6" Fiberglass steam pipe, rated to 280 PSI. I got the stuff from my grandfather when I was visiting him over the winter break. The bushing in the bell towards the bottom is a 6" slip to 4" female PVC bushing, purchased fom mcMaster. because the pipe however is fiberglass, it didnt fit perfectly, it is therefore rammed in as far as i coul get it, and bolted into place. The ammo stop is a piece of 1/2" threaded rod. Much more infor about this project available over at spudtech in <a href="http://forums.spudtech.com/topic.asp?TO ... 5381">This Thread</a>.
<b>Combustion Chamber</b> - 39" x 6"
<b>Barrel</b> - 54" x 6"
*approx ratio is .72:1
<b>Ignition</b> - BBQ ignitor producing a single spark towards the rear of the chamber.
<b>Primary Fuel</b> - Metered propane, there is a 53" piece of 3/8" PVC tubing. It takes 15 shots with this meter to fuel the chamber.
<b>Ammunition?</b> So what fits in a 6" diameter pipe? Plant pots. And old Large Yuben coffee cans...[twisted]
<a href="http://img243.imageshack.us/my.php?image=img0606nm2.gif" target="_blank"><img src="http://img243.imageshack.us/img243/4417 ... nm2.th.gif" border="0" alt=""></a>
<i>how the pipe was after the insulation was stripped off
<a href="http://img148.imageshack.us/my.php?image=img0607ri8.gif" target="_blank"><img src="http://img148.imageshack.us/img148/3322 ... ri8.th.gif" border="0" alt=""></a>
<a href="http://img243.imageshack.us/my.php?image=img0618av9.gif" target="_blank"><img src="http://img243.imageshack.us/img243/5344 ... av9.th.gif" border="0" alt=""></a>
post-priming and bushing installment
<a href="http://img201.imageshack.us/my.php?image=img0619nt2.gif" target="_blank"><img src="http://img201.imageshack.us/img201/7893 ... nt2.th.gif" border="0" alt=""></a>
ignition on left, fuel injector top-right
<a href="http://img224.imageshack.us/my.php?image=img0635eb9.gif" target="_blank"><img src="http://img224.imageshack.us/img224/7113 ... eb9.th.gif" border="0" alt=""></a>
full cannon shot
<a href="http://img167.imageshack.us/my.php?image=img0637hv5.gif" target="_blank"><img src="http://img167.imageshack.us/img167/2203 ... hv5.th.gif" border="0" alt=""></a>
propane meter
<a href="http://img132.imageshack.us/my.php?image=img0636ym3.gif" target="_blank"><img src="http://img132.imageshack.us/img132/1287 ... ym3.th.gif" border="0" alt=""></a>
projectile stopper
<a href="http://img132.imageshack.us/my.php?image=img0638ty7.gif" target="_blank"><img src="http://img132.imageshack.us/img132/1880 ... ty7.th.gif" border="0" alt=""></a>
flower pot
<a href="http://img411.imageshack.us/my.php?image=img0641ew2.gif" target="_blank"><img src="http://img411.imageshack.us/img411/990/ ... ew2.th.gif" border="0" alt=""></a>
holy coffee can batman!
<b>Combustion Chamber</b> - 39" x 6"
<b>Barrel</b> - 54" x 6"
*approx ratio is .72:1
<b>Ignition</b> - BBQ ignitor producing a single spark towards the rear of the chamber.
<b>Primary Fuel</b> - Metered propane, there is a 53" piece of 3/8" PVC tubing. It takes 15 shots with this meter to fuel the chamber.
<b>Ammunition?</b> So what fits in a 6" diameter pipe? Plant pots. And old Large Yuben coffee cans...[twisted]
<a href="http://img243.imageshack.us/my.php?image=img0606nm2.gif" target="_blank"><img src="http://img243.imageshack.us/img243/4417 ... nm2.th.gif" border="0" alt=""></a>
<i>how the pipe was after the insulation was stripped off
<a href="http://img148.imageshack.us/my.php?image=img0607ri8.gif" target="_blank"><img src="http://img148.imageshack.us/img148/3322 ... ri8.th.gif" border="0" alt=""></a>
<a href="http://img243.imageshack.us/my.php?image=img0618av9.gif" target="_blank"><img src="http://img243.imageshack.us/img243/5344 ... av9.th.gif" border="0" alt=""></a>
post-priming and bushing installment
<a href="http://img201.imageshack.us/my.php?image=img0619nt2.gif" target="_blank"><img src="http://img201.imageshack.us/img201/7893 ... nt2.th.gif" border="0" alt=""></a>
ignition on left, fuel injector top-right
<a href="http://img224.imageshack.us/my.php?image=img0635eb9.gif" target="_blank"><img src="http://img224.imageshack.us/img224/7113 ... eb9.th.gif" border="0" alt=""></a>
full cannon shot
<a href="http://img167.imageshack.us/my.php?image=img0637hv5.gif" target="_blank"><img src="http://img167.imageshack.us/img167/2203 ... hv5.th.gif" border="0" alt=""></a>
propane meter
<a href="http://img132.imageshack.us/my.php?image=img0636ym3.gif" target="_blank"><img src="http://img132.imageshack.us/img132/1287 ... ym3.th.gif" border="0" alt=""></a>
projectile stopper
<a href="http://img132.imageshack.us/my.php?image=img0638ty7.gif" target="_blank"><img src="http://img132.imageshack.us/img132/1880 ... ty7.th.gif" border="0" alt=""></a>
flower pot
<a href="http://img411.imageshack.us/my.php?image=img0641ew2.gif" target="_blank"><img src="http://img411.imageshack.us/img411/990/ ... ew2.th.gif" border="0" alt=""></a>
holy coffee can batman!