Hipponater

I'm working on making a Doomsayer as a last summer project before I have to slow down my work for college. (Mainly due to lack of tools at my apartment). All was well until I was reassembling the turret so I can test the rotation mech.

When I have the turret assembled like shown

(shown outside of the larger black piece to show order, it's correct, isn't it?)


Another view, pieces spread out

the metal bar does not extend out of the last big beefy gear piece to attach my 1/8" pushnut fastener. As can be seen here:


and here:


I've read how important that fastener and it's position is, so I don't want to cut down the black plastic tube on the big beefy gear to expose more metal bar without first getting some advice.

I've taken off the pushnut fastener from the other side (the part of the turret facing away from the plunger tube) and put on a new one hopefully a little further up the rod to get me a little bit of space, but it didn't work.
My gears were glued where AssassinNF glued his, seen here, because I'll be using CPVC barrels. I took off the glue, but I still don't have enough room.

Here's some pictures of my glued over spring. The center is wax paper, I had to be creative in how to be able to get it off the beefy gear without using lube.
It's flat at the top and bottom, except where I've tried to cut away a little. It does not compress at all.






and here's a picture of how much of the metal bar is extending from the other side:



I think the problem is that the flat plastic disk that goes over the spring is sitting too high. But to go lower, the spring must compress. Has this happened to anyone else? How should I fix it?

Edit: Changed some spacing.

Edit 2: Thanks, Salmon, I took off some hot glue and got it working.

(If you just want to see the mod, skip to Materials and Tools)

The Lanard Hand Cannon (LHC) is pretty cool right out of the box. It shoots huge (nearly 1” OD) darts that look like jumbo stefans. This gun really has potential. The internals are sturdy (and can be reinforced) and the plunger tube is fairly large.

This modification will go over a few things. We’ll be extending the plunger draw to move more air, improving the seal, adding a spring, as well as adding PVC coupler with minimal dead space. Finally, we’ll be reinforcing the internals so that this puppy can last war after war.

First, open it up. All screws are the same length except the one under the pump handle; it is a little bit shorter. Take note of the internals, the catch and trigger mech are a little different than the usual springer. Because of this clicking plunger draw, we can extend the pump pull and get more air moving faster.

Some of the other mods (using a recon spring) as well as wrapping the coupler in e-tape may have come from Darken.


Materials and Tools Required
Materials:
Recon Spring (or other spring)
Epoxy Putty
PVC Coupler
JB-Weld (or epoxy)
Electrical Tape
Hot Glue
Canned Liquid Foam (used for straw mods and such)
Tools:
Dremel (Cut off wheel and sander attachments)
Hot Glue Gun
1/4” Drill bit and Drill Press (Preferred, but a hand drill or dremel will work)
Ruler
Marker

First, let’s start with the plunger rod. The stock seal is terrible. There isn’t much seal at all. Wrap some electrical tape (tightly) around the outer larger ring (Just under 2 wraps). The top of the tape should be about even with the very end of the plunger rod.
It should look like this:


Next, take your canned foam stuff and fill all the dead space. Leave it slightly under the edge of the tape, as we will be adding hot glue. You can use hot glue instead of the foam, but then it is not removable if need-be.


Now add hot glue over the top to add some toughness to the top. Also, glue on your foam cushion. I used a ring from an old disk shooter, cut down to fit.





Finally, add a spring. I used a recon spring and a stock spring. I got the recon spring on by force, then twisting once it was started.


A note about spring replacement: The plunger rod is really wide, so a spring to be used must have a larger ID. A #49 is just slightly too small.

As always, add lube to the plunger tube and ensure a tight-ish fit.

Now, take the plunger slide mover rod thing. Lightly sand the pieces to be reinforced and add epoxy putty as seen below.



I outlined the epoxy putty because it’s tough to see with the color of the plastic. This piece is much sturdier than that of the PAS, also easier to reinforce. Keep the epoxy putty flush with the plastic so it can still slide in the shell.

Now, place back the internals, (take the springs off the plunger rod), and line them up. Click the plunger rod back. It should click 8 times. Move the plunger rod so that it clicks a 9th time. Mark where the shell needs to be cut, like so:



Then, cut out along the green so the plunger draw piece can slide. I think I used a 1/4” drill bit. Drill it out, and then cut it with a dremel. Sand down the other pieces. They just slide together; no screw will go in that post.


When you’re done, it should look like this:



Repeat the process with the other side of the shell.

Now, we need to make the plunger handle be able to move the slide back that far. The easiest way is to cut the handle, rather than cut the shell. (While doing this late at night, I started to cut the shell; I had to repair with epoxy putty, which is why my gun has the putty on the side).
Line up the handle with the holes so you can gage how much needs to be cut.


Cut off the end.

Here it is compared to a stock one:



And here’s a shot of the end. It’s about flush with the brace piece that comes across.


Now, let’s add a coupler.

Cut a PVC coupler in half. Sand down the bottom so that it will fit level and the barrel will not be crooked. It fits in the large orange piece perfectly, and fights perfectly on top of the smaller one with the AR. Drill out the AR.




Take the two orange pieces with the AR and the peg, and drill/dremel them out. I drilled out the smaller one and dremeled the other one with the sanding attachment. Wrap electrical tape around the PVC coupler leaving you room for adhesive at the bottom. It should fit well in the fake barrel. Not too snug, but a nice fit. If you plan on RSCBing this guy, cut the fake barrel to the same length as the coupler. (Or suffer from extra dead space).
Line it up like this:


Then line it up and JB-Weld it. Clamp it while it dries.

Picture Limit Reached, Continued in next post.

Edit: Shit, I forgot to test it the other way and it doesn't quite work. More at bottom

After seeing Split’s Hornet Shuttle Valve Mod, I wanted to make one, it's an amazing mod, however, at $10 apiece from McMaster, the shuttle valves are too pricey for me. I was looking around trying to find them cheaper when I ran across the picture here http://www.kepner.co...ttle_valves.htm and figured they could be made. The goop on mine are still drying, but they should be in a hornet tomorrow. I blew into them and it worked perfectly, but after the goop is finished drying, I’ll assemble it and see the real results.

Materials needed:
4” of 1/4” OD, .170” ID vinyl tubing
7/8” of 3/8” OD, 1/4” ID vinyl tubing
3/8” of 1/2” OD, 3/8” ID vinyl tubing (optional, but recommended)
BBs. (1 per)
1/4” dowel rod (5 or so inches)
Goop

Tools needed:
Your preferred cutters for tubing (X-acto knife, razor blade, etc)
Drill Press (preferred) or hand drill
1/4” drill bit

Start with your materials


Cut your 1/4” OD tubing into 3 parts, two will be the ends of the shuttle valve; the third will be the air exit. I cut all mine to about the same length.
Take the 1/2” OD tubing and slide it over the 3/8” OD tubing and center it. Like this:

This is slightly difficult, I took my vice, adjusted it to an opening of 3/8”- 1/2” and set the piece on it, then pushed the inner tube down while the edges of the vice held the outer tube from moving.

Once you have that centered, congratulations, you’ve finished the hardest part.

Now, slide in your 1/4” dowel to the two tube piece you just made.

The dowel will hold the tube so it does not collapse on itself while you drill. Drill a 1/4” hole (centered in the middle of the 1/2” tubing) through the 1/2" tube and through the 3/8” tube until you hit the dowel. Don’t drill through the other side of the tubing. Slide out the dowel. It should now look like this:


Now, put in one end of the input tubes, they form the top of the T shape. Put in the piece on the side and the bb. Make sure the side tubing does not protrude into the center, that will prevent the bb from moving and your valve won’t work.



And finally, add the other side.


Now, you can check it by blowing in one of the top parts of the T shape. The air should come out the side tube, but not the other end. If it all works, goop it up!




And you’re finished and ready to make a backpressure gun kick ass.
Hopefully it works, it seems to now, but we’ll find out when I put it in the hornet. Any tips/suggestions?

Edited to change spacing.

Edit2: Shit, I tested again by blowing in one output with the bottom plugged, it doesn't seal entirely with the other side, some air still leaks out. I'm working on fixing it by various means (changing from BB to 1/4" slingshot weight to other ball bearings) and funneling the edges of the tubes, anyone have any tips?