160 replies to this topic

[CaptainSlug]

The piece out the back is a folding stock. It hinges forward and locks onto the barrel to become a foreward grip. I can route the tubing through the butt of the stock to keep it from dangling under my arm.

Length of the gun with stock folded: 18 inches
Length of the gun with stock extended: 28 inches

4 inches shorter than a Longshot when folded, but it's much skinnier (1-5/8" wide)

Edited by CaptainSlug, 19 September 2007 - 11:11 AM.

[Nonsense Man]

Oh ok I kinda expected it to be smaller but its still going to be awesome.

[Z-man12]

So the valve you built the other day. I wan't to make sure I understand correctly, its basicly a lager verson of the RF20 type valve. Am I correct in assumeing that?

Your really buckleing down on this project. I am glad to see its getting done.

[CaptainSlug]

So the valve you built the other day. I wan't to make sure I understand correctly, its basicly a lager verson of the RF20 type valve. Am I correct in assuming that?

Not quite. The RF-20 valve is a push-button valve (like your average ball valve in function but easier to actuate). The one I had to make is a 3-port 2 position directional control valve. The off-the-shelf models are ridiculously restrictive, or prohibitively expensive and bulky. The valve has to alternate which port connects to the blast chamber while sealing off the opposite one.

Mechanically a more annoying task to accomplish and it took me a good deal of time to get a working design together. Hopefully this latest one does everything I need it to.

A = Air Cylinder and Blast chamber
P = Paintball Tank
EA = Barrel

Position 2 being the state that's active when the trigger is not pulled.

Edit: The valve is back together with new O-Rings and washers. It works but much better than before. I also got the shortened barbed fittings installed.

Edited by CaptainSlug, 19 September 2007 - 04:32 PM.

[Z-man12]

So it works sort of like this then. (Blue lines = air)



I just want to be compleatly sure I understood what you wrote above.

[CaptainSlug]

Yes that's basically correct. I can mount the valve in the gun facing forward or backward, depending on who the trigger is cut and the spring is placed.
You can understand the mechanics better with a larger version of the drawing.

http://www.captainsl...valve_split.gif
The washers on the center rod press against either of the two O-Rings in the center chamber to create a seal. This blocks the nearby port off from the center port and connects the opposite port.

I also just got an E-mail from my boss letting me know that he finished welding my internally mounted tank. I can lathe it down at work tomorrow and then test everything.

Edited by CaptainSlug, 20 September 2007 - 01:50 PM.

[CaptainSlug]

Testing all the pneumatic components together for the first time. Things are working, yay!

Edit: Forgot to show a better picture of the tank. It's a length of 5/8" OD aluminum tube with two threaded adapter bushings welded into each end. The ends were then lathed down to match the original OD.

Edited by CaptainSlug, 20 September 2007 - 11:24 PM.

[shadowkid33]

Two things. First off, I'm so glad to see this finally being turned into a working prototype. I can't wait to see it in a war, especially in the civil war rounds.

Second,

Is that based of a three way valve for paintball guns?

[CaptainSlug]

It's not based off of anything in particular. It's the eighth valve design I've come up with for just this gun.
Tomorrow I start machining.

Edited by CaptainSlug, 20 September 2007 - 06:17 PM.

[Lynx]

Wow, Captain Slug is pulling off a semi automatic nerf gun. That is freaking awesome! When will the other major projects like the shotgun, artillery (in general i.e. the Artillery thread/gattling gun), and "The Cole Breech"...Bum Bum Boom!

[bobafan]

How will you carry the HPA tank? It's not really big enough to strap to your back like low pressure air tank.

When do you expect it to be assimbled and in working order?

I have a fairly technical mind, but there is no way I could figure any of your great projects out by myself.

I just hope I will be able to see them in person at some war.

[CaptainSlug]

1. How will you carry the HPA tank? It's not really big enough to strap to your back like low pressure air tank.
2. When do you expect it to be assembled and in working order?

1. Not big enough? Haha, that's funny considering the tank is about the size of a medium sized watermelon. It fits comfortably into a camelback bag.
2. Sometime next week.

Late Night Edit: Change of plans. I'm going to make a new valve based on the current design, but much simpler to machine and rated for higher pressure levels. The current valve is having issues with o-rings creeping out of place. The design and configuration works, but I want to make a more robust version.

Edited by CaptainSlug, 21 September 2007 - 01:48 PM.

[six-five-two]

1. It fits into a camelback bag.

So you could drink out of it and hold your tank at the same time?!

[CaptainSlug]

After two hours of work the new valve is machined. I will assembled it and take a photo tonight. I made it out of solid piece of black Delrin and it should be rated up to 200psi. It will also get a slightly higher flow rate.

It also has an adjustable tension on the spring return. I used an online claculator to figure out that the spring will have to apply atleast 3lbs on the valve rod to keep it sealed @ 50psi.

6PM Edit: Here's the Photo

Edited by CaptainSlug, 21 September 2007 - 05:09 PM.

[King Of Butt Land]

That's really sexy. How much did that block of delrin set you back? Seems like it would be great for machining valves what with all the self lubrication.

-butt

[CaptainSlug]

It was made from a 1" diameter rod I had leftover from a previous project. Delrin in round rod form is pretty affordable (1" Diameter is $4.16 per foot).
And yes it is an awesome material to machine.

Edited by CaptainSlug, 21 September 2007 - 05:58 PM.

[Cennipe]

How did you thread that?

[King Of Butt Land]

Usually you would use a pipe tap. Unless however you're super machine-shop man and have pipe taps in your fingers.

-Butt

[CaptainSlug]

How did you thread that?

I have my own set of taps plus a good number of pipe taps that I've been collecting. The materials engineering lab I work at also has a wide assortment of taps.

All of the work on the valve so far was done using the lab's manual knee mill and manual machine lathe. All of the gun parts made from round rod will have to be machined using the lathe in order to make sure they're accurate.

[Nonsense Man]

What kind of material will the case be made out of?

[CaptainSlug]

Most of the gun is going to be made out of polycarbonate sheets in 1/4", 3/16", and 1/8" thicknesses. The aim is to be able to put the gun together "naked" in that everything can be mounted to the frame and function properly without having to be enclosed. This will allow for easy adjustments of components without needing to completely dissect the gun. Some adjustment points will have open access ports that I can put tools into.
The protective cover will either be the same material or be made from polystyrene (if I can get it to cooperate).

I already have all of the raw materials I need. I'm going to start the majority of the machining on Monday. I have a bunch of miscellaneous stuff I need to work on tomorrow.

Edited by CaptainSlug, 21 September 2007 - 09:53 PM.

[CaptainSlug]

Just tinkering with color options. I had other stuff to take care of today.

Edited by CaptainSlug, 22 September 2007 - 05:23 PM.

[the beast]

That paint job would be so awesome. Im hoping this project turns out well. But for an extremely inexperienced painter like me it would be extremely hard.How are you going to paint it? With painters tape or our they all seperate pieces.

[CaptainSlug]

They're separate pieces that I will paint with vinyl dye.

[PharaonArin]

That thing is going to be a fucking beast. Now your going to have to develop a bigger magazine so you dont run out of darts in like 2 secs.

I cant wait to see the finished product.