I love the design of the Rainbow Pump and the recent Pump Snap but I don't have the time or patience to machine polycarbonate or figure out how to make a snap not fail after catching 3 times. So I came up with this. I'm not saying this is completely original because its not. Similar homemades can be found all over the NIC but this is my version of it. It's catch is the easiest, cheapest and most reliable catch that I have ever worked with. Ring catches have been around for a while now but they always required a T sticking out or some other variations requiring a lot of sanding and such so I came up with this.
All the pictures were taken after I built it so I'm missing a lot. And it's very unorganized at most points. My next ones will be much better than this.
Materials-
1 ½” PVC
2” PVC
1” PVC T
1” PVC coupler that fits inside 1 ½” PVC x2
small bits of various sizes of PVC
corner bracket
small hinge
small catch spring
1/2” pex or cpvc
½” reducer that goes inside 1 1/2” PVC for barrels
To build the blaster, you cut two segments of 1 ½” PVC, one 14” and the other 8.5”. One the smaller piece, you cut slots in both ends so a bolt can go through them. You then put a 1” coupler inside so the two segments can be connected and put the T on the end.
Then you need to take some PVC segments so you can fit it inside the pressure chamber and allow the plunger rod to slide through it with little friction to make the spring rest
To make the catch, cut a piece of pipe that can slide over your plunger rod with a bit of room. I think I used 3/4”. Get a wood screw and cut it down like this:
Make the plunger rod like this: your seal of choice on the end, at the point of near max compression, add the size of the spring rest and make a grove like any other ring catch gun.
Glue/screw the reducer into the front of the gun
Put the spring on the plunger rod, then put it all the way inside. Then put the spring rest on it and screw it in so the spring is compressed slightly. Then you screw a hole in the catch ring and a slightly larger one in the pressure chamber so that the part of the screw without threads can slide up and down. When the catch is assembled, the catch will almost touch the spring rest. You put the spring on the screw, then screw it into the PVC then slide the ring on and screw the small part into the ring. This is confusing me and I designed it, so heres a picture. Its very simple but hard to put into words.
Next, you attach the front to the back. I used pop rivets because I didn't have screws that would let me slide the 2” PVC on top of it but if you have small enough screws, do it that way. The top of the blaster should be where the grove faces up.
Next cut the sheath for the pump action mechanism. Leave a small gap on the side where it is closest to the back so that it can slide past the catch screw. I didn't take a picture of this when I had the gun apart so refer to the first picture for how I did it.Slide it on and proceed to the next step.
Next is the trigger. I riveted a angle bracket from a broken snap to a hole in a small hinge. Then I screwed the hinge onto the pressure chamber so that it could move and push the screw up but not tight enough to prevent the catch from staying engaged.
Next I cut out a handle from a broken dart tag blaster and used tone for the handle and one for the pump grip. I used six screws to screw it on. Check to make sure the catch stays engaged before and after this because it sometimes interferes with the catch and caused me trouble the first time I put it together.
Next you put a bolt in the plunger rod so that when the sheath goes back, it pushes the plunger rod back. You also can put a string to prevent dry firing damage to the gun.
I took these pictures while I was disassembling the gun so everything is backwards and I forgot to take pictures of a lot of things.
Here is basically how the catch works:
Edited by LilNickyG, 19 November 2011 - 12:23 PM.