Working Cannon (Not Print in Place)

Here is a remix of the Print in Place Cannon by Makkuro . I really like the original and the print in place design is very well done. I found though that PLA was not very forgiving and coil spring broke after just a few fires. This remix takes Jürgen Weigert rounded design, removes the firing mechanism and includes a seperate plunger with a screw on knob so that a compression spring can be added post print. In my design I uses a 9mm diameter by 35mm long compression spring. I had this in a kit of springs I bought on Amazon a while back, but you could use any compression spring from 7mm x 30mm upto 14mm x 40mm, although I haven't confirmed these sizes. The knob is a screw fit and easily removed, so different springs can be tested. If you already printed the thick rod version of the original and the spring broke, you could possibly retro-fit the plunger to the original print. I printed mine with .6 nozzle .2 layers.