Wednesday, March 28, 2012

SSPB Pump Replacement


I've been trying to build something primary worthy out of a SSPB and this comes close. I would like to try a third one with a few tweaks to see if I can get there. I get 100' but would like 120'! It holds 8 shots with a 1.1" dart. The wye uses a cpvc elbow, a cigar tube hopper and a little tubing nested into the stub to match the blast valve size better (Thanks torumatoko4!) The stub is kept inline with the barrel when trimmed to shape. I like to do it this way for aim but it also seems to improve airflow.


The pumps are from a Buzz-Bee Equalizer water gun. I selected them for their thin size. I wish I had some even thinner ones. I have to look at some other pumps.


For a full look visit Nerf Revolution or The Home of Foam!

Thursday, March 22, 2012

Spider-Man Helix / 4B Shotcannon



The internal volume of the tank expansion was sized to the available space in the shell. I added a simple string/spring trigger attached to the 4B's lever along with a spring against the blast valve. It needs re-doing, but I hate triggers and always put them off! I used 3/4" threaded fittings. At the time I only had the male fitting in conduit. I would normally like to use cpvc threaded fittings as they seem more durable and precise.


The barrels are spread horizontally by a piece of thinwall pvc. It gives a much better spread at range.


The performance of this blaster/attachment combo is impressive. It makes quite a sound when fired at high pressures! It was made for .8" darts. It holds 80 at that size and gives 2-3 good shots. It can get darts out to 100' but only at higher pressures. The spread at range is 20-25'. I have a feeling that I can improve the pattern a bit with those rifled, dollar store baton barrels. The pattern starts at about 40' and goes out to 80' with good coverage. Safety is certainly a concern with this much power. I sized things for 1 pump close range shots. With 20+ darts leaving the barrel, the energy each dart has is safe. I would not fire this thing at anyone at close range with a few pumps. The effort involved in getting 100' pressure is quite high. Still I would love to do an adjustable oprv or pressure regulator on this in the future. I would also like to try shmmee's oogoo darts. I plan on separate write-ups on the blaster & attachment,