UPDATE 24th of May 2019
Released an improved final version of the blaster which can be found here
UPDATE 27th of April 2019
-Made a Stock attachment lug which can be found here
UPDATE 31st of March 2019
-Adjusted the Plunger Seal Cutting Jig, the cutouts are now offset to lineup with the breach better, the holes should be towards the top when installing the plunger tube.
-Optimized the O-ring track diameter on the Plunger Head for better performance.
UPDATE 30th of March 2019
-Moved the spring placement point on the breach for faster breach return.
UPDATE 25th of March 2019
-Added files for an automatic jam door, that opens when the breach is in the loading position and closes when the breach is in the firing position, which is helpful for avoiding jams when one of the barrels fails to fire it's dart.
-Uploaded source files for the parts related to the plunger assembly for those that wish to modify them for other sizes of PVC https://www.thingiverse.com/thing:3516329
UPDATE 24th of March 2019
-Made a revision to ShellFront, if you have already printed that part it will not need reprinting, however some shell cutting will be needed, See Addendum 1 at the bottom of the most recent build guide for what plastic to remove.
UPDATE 21st of March 2019
-Fixed incorrect link to the wrong product for PVC B in build guide.
-One of the breach pusher tabs broke on the pump grip, so I have changed the print orientation, which should strengthen that part, Print instructions for that part have also been updated. Also revised the pump to make the return stroke less sticky.
-I noticed an issue with the breach not returning quickly enough if you pump the grip forward too fast, Which I think this is due to the breach being heavier than that of the prototype's, so I have revised the print instructions to no longer print it at %100 percent infill. I will revise the spring placement on the breach in a future update to make it pull harder when the breach is released which should result in a faster return.
-the C836 spring makes the prime very difficult and also makes the blaster unbearably loud when firing, So I would advise against using it without ear plugs.
UPDATE 20th of march 2019
-Tweaked the length of pvc used in the plunger to get full travel with the pump grip, previous plunger length was stopping the stroke short and causing pusher arms not to fully elevate. Also tweaked length of spring retainer pvc to compensate. See updated build guide.
-Also decided to try the Century 836 spring ( https://www.bunnings.com.au/century-spring-corp-22-2-x-101-6mm-compression-spring_p3970395 ) made famous by the Make Test Battle Sledgefire mod video, which I think is around 12 kg, performance is much improved, hopefully the shell and breach can hold up to that much power.
This is the BETA release of THE SCATTERSHOT, a foam dart launching, pump action, Spring powered, 3d printed blaster. It fires 3 half darts per shot in a 3 degree spread, is fed from an under slung horizontal box magazine and has a 12 + 1 shot capacity. Read the included build guide thoroughly before attempting to make this.
This page only includes the blaster, the magazine can be found here https://www.thingiverse.com/thing:3497413
To operate the blaster, load the magazine with up to 12 darts per stack, then, with the pump in the forward position insert the magazine by pushing it up and forward into the magwell till it catches in place, the darts must be facing up. then prime the blaster by pulling the pump back all the way till the trigger catches then all the way forward, the blaster is now ready to fire, half priming will more than likely jam the blaster. To remove the magazine, push the mag release button in the trigger guard. In order to help prevent dry firing, the blaster will not prime when the magazine is empty. Do not dry fire the blaster, or fire it when the pump girp is not in the forward position, as this can damage the blaster.
I have successfully tried springs up to 10 KG, I don't how much higher of a spring load the blaster can take.
To avoid potential injurys, be sure to wear safety glasses and ear plugs and all other appropriate safety equipment when making and using this blaster.