72 replies to this topic

[Split]

Part 1:
Plunger replacement.

I'm feeling like shit, but I thought I'd post this up. This is the first part of my overhaul that I've been talking about.
To start, I wanted to replace the puny plunger tube, that could only fit a firefly spring.
I had a lot of ideas, and I wanted to push the boundaries on how much volume I could make it. Since the gun is automatic driven by a gear train, the plunger travel distance has to stay the same, so in order to increase volume, the plunger tube had to be of high diameter.
Measuring out the internals, I could fit up to a 3" diameter tube in there, which, when combined with the plunger stroke of ~2", gives as much volume as a longshot plunger tube (stroke of 4"). This however, proved to be not easily feasible.

Searching through my box of random supplies, I found one of my older ideas. Using empty caulk tubes as plunger tubes, and the slider as the plunger head. The slider on the inside makes the most perfect seal (think 1.5" neoprene washer in a LS plunger tube <- props for that one Slug), because it can't let any caulk through (or the caulk gun wouldn't work). These tubes are cheap, like $2 each, and I'm sure any construction site that has them won't mind giving you some. I happened to have had 6 or so.

Anyway, the best combination I found for making my plunger head with the Vulcan plunger head was this:
1/2" wood screw (mine came with a "middle hinge" from home depot)
#8 washer
Slider
1 1/2" x 1/4" fender washer
Vulcan plunger head

You need to clamp and pre-drill the Vulcan head as centered as possible. Also pre-drill the center of the slider. I used a 3/32" bit; I would recommend using that or smaller.

Here it is assembled:


With this new plunger head you can now use significantly larger springs. I currently have a Longshot spring on here, with about 2 coils cut off.


This also allows you to combine springs. You could fit a BBB spring inside of the LS spring, and still have room for both a Manta ray spring and a Firefly spring with the Vulcan spring. That of course would destroy your gun in a heartbeat, but I just want you to see how versatile this is now.


I had to cut down a significant portion of the plunger tube holder. If you are repeating this, you will also need to remove both the Sealing mechanism and the manual cocking mechanism. Cut carefully, and be sure not to impede on where the rotation arm mechanism goes. (See the Labeled Vulcan Internals for reference)


Important: Look at my finished plunger tube. This is the top of the tube. In order to get this piece, cut off the tip about halfway down (the more conservatively done the better; you can cut more off later), and push the slider out with something long and thin. I used a threaded rod. Rinse out the plunger tube and slider with hot water.
Also, look right behind where the plunger tube is. When cutting to make space for the tube, be sure to leave that lip there. That, and a similar piece on the other side, keep the tube in place. Without it, the tube will move with the plunger, because the seal is so perfect, and no air will be moved (making the blaster a dud).

On there is a 1" piece of 19/32" brass, and inside it is a 9/16" piece. I have yet to determine the best barrel length.

You will need to cut down this nub on the top half's shell to allow it to fit over the new plunger tube.


Overall, the plunger tube inside diameter went from about 3/4" to 1 3/4" (233% increase), the spring became triply as powerful, and the seal became perfect enough to be able to stop the plunger with ease.

Thus concludes part one.

Edited by Splitlip, 09 September 2008 - 12:08 PM.

[Rogue Warrior]

Wow, splitlip you just made an excellent idea. This thing will go down like the deoderant clip. Now I'm thinking super nightfinder. That vulcan will rock.

[Swords]

This is amazing. How is the performance and reliability after this awesomeness mod?

[AJZ]

This is amazing. How is the performance and reliability after this awesomeness mod?

I don't think he's done thus the 'Part 1' at the bottom so I would guess he'll be adding more of the overhaul later.

I really didn't think the vulcan would have much power or reliability until now. Seems like waht you've done here is a taste of what's to come and the fact that your vulcan will be sheer awesomeness. Hope is goes well

[TheNerfLoki]

Wow... That is awesome. Hopefully the vulcan is more reliable now.This is just a general idea but can you find out what keeps breaking in everyone else's vulcans and fix that too?

[Lynx]

You just asked him to do all the legwork for a problem you have,

You greedy bastard!

[g-force]

I'll have to try this but doesn't that decrease the rof which is the entire point of the vulcan? If it does that doesn't matter I mostly use mine as a 25 clipped longshot. Good job though.

[Split]

If you've ever been to a war, you'd see that the ROF is just unnecessary after a certain point. Yes it does decrease the rate of fire slightly. That's why it's so important that you choose what balance you want in the springs. Put in a million springs and have high range, low rate of fire, or put in a couple weak springs and have a high rate of fire and low range. I think that a shortened Longshot spring, plus maybe a first gen Firefly spring is where the happy medium is. I'm leaving it there for me.

Also what is important are the batteries. That's why I present

Part Two:
Variable Power output

I've mentioned in other threads that I feel that 14.4 volts, giving about 4-5+ rounds per second is complete overkill. But I don't think I'm ready to completely negate that option by just wiring my blaster up to one battery.

What I've done here is have two 7.2V batteries that I can switch between using one or both, on the fly. If I want I can even unplug one so that I don't have to carry around the extra weight.

This allows for maximum versatility in the field. In between rounds I can choose how I want to set up my Vulcan. A Phillips screwdriver allows me to add or remove springs quickly, and this new part can manage the weight and power of the gun on the fly.

Here is the overall wiring setup:


And here are the diagram schematics to make this work. If you know how to wire this stuff up, this should make sense (the switch is a SPDT, or one side of a DPDT can be used). If you don't know how to wire this up, you should not start with this, so I will not explain in depth.


And here is the switch finally installed on the blaster. Switch it one way for a normal pace on one battery, or to the other for a boost!


Thus endeth Part 2. Enjoyeth.

Edited by Splitlip, 13 August 2008 - 05:41 PM.

[Bomberman]

Oh. My. God. This is like, Frankenvulcan. The new plunger tube was genious! This kind of plunger would make a Super nitefinder alright, or really, a super anything! But on the fourth picture in your first post, what does the brass barrel do? Is the chain going to feed between two pieces, and the dart slide down the brass barrel? I must have missed something, because I am not really sure how this is going to work. I understand the new plunger, and battery replacements and everything, but the brass barrel picture has me perplexed.

[slowguitarman]

Oh. My. God. This is like, Frankenvulcan. The new plunger tube was genious! This kind of plunger would make a Super nitefinder alright, or really, a super anything! But on the fourth picture in your first post, what does the brass barrel do? Is the chain going to feed between two pieces, and the dart slide down the brass barrel? I must have missed something, because I am not really sure how this is going to work. I understand the new plunger, and battery replacements and everything, but the brass barrel picture has me perplexed.

Yes, you did miss something. His vulcan has no rotation mech. That means no chains. He singled it.

[Split]

My rotation mechanism broke. I have no chain and what not. See here, here and here. I plan (I don't mind saying this here as I've said it elsewhere, and as you can see I hold true to what I say) on making the gun breechless hoppered. There are other designs in the works on that note though, in case the hopper dealio proves too difficult. But those are all for another part (at least 4 or higher).

Edit: You guys are insane. The next two posts should just be deleted.

Edited by Splitlip, 13 August 2008 - 02:05 PM.

[Rogue Warrior]

A singled Vulcan? Doesn't that destroy it?

[Bomberman]

A singled Vulcan? Doesn't that destroy it?

No, it BROKE. So he pretty much HAS to single it. He is putting all the extra power he can get out of it.
But okay, I must have not read a part of the other thread. Oh well. Still, and amazing mod.

[imaseoulman]

Splitlip, Congratulations. You may have single-handedly redeemed the Vulcan! Is there any chance you can get a video of this thing firing? I'm trying to gauge if it is worth the time and effort.

About ROF, my main concern is how long it takes to get the first shot off. I haven't seen one of these in action so I'm still not crystal clear on the cocking mechanism, but can this thing stay cocked for a while before shooting, or does it have to fire right after being cocked? My concern is pointing it, needing to get a shot off and having to wait half a second for the motor to pull back the plunger. I know you can prime it manually, but can you prime it with the motor without it firing? Hope this makes sense. Your efforts are appreciated.

[angelof DEATH182]

Double-long Breechless Deodorant Clip.
All I have to say.

[Split]

Splitlip, Congratulations. You may have single-handedly redeemed the Vulcan! Is there any chance you can get a video of this thing firing? I'm trying to gauge if it is worth the time and effort.

About ROF, my main concern is how long it takes to get the first shot off. I haven't seen one of these in action so I'm still not crystal clear on the cocking mechanism, but can this thing stay cocked for a while before shooting, or does it have to fire right after being cocked? My concern is pointing it, needing to get a shot off and having to wait half a second for the motor to pull back the plunger. I know you can prime it manually, but can you prime it with the motor without it firing? Hope this makes sense. Your efforts are appreciated.

I'll try to get a video. The answer to your question is no it won't stay cocked. It's really not bad at all. It scares me at how fast it goes as soon as you press the trigger. There is no half second delay. It's really about the same as pulling back on a Firefly or Mav trigger, where it has to rotate the turret. You'll survive.

Thanks AOD. I was hoping for something more than 16 shots though.

I'm not done yet guys. Some of the more important parts have yet to come.

[Jabulus]

Put in a million springs and have low range, high rate of fire,

I sure hope not.

Anyway, this definitely ups the intimidation factor, even if it's going to be singled. I gotta say, I didn't think it was possible to modify the vulcan very well because of the integration of electronics and mechanics that make up this gun. Looks like you proved me wrong.

[analogkid]

Very nice. Can't wait to get one myself. How are your battery packs wired, series or parallel? If you wire them in series, I believe the motor spins faster/receives higher voltage and if its parallel then the motor will have more torque/more available current. I can't tell from your wiring diagram, its kinda unclear. If the motor strains pulling back larger springs, more torque would be a help.

EDIT: Yeah I totally spaced on the part where he said 2 7.2V batteries for a total of 14.4V. Can't find where it is referred to as series though, but I should have guessed. However, I just checked Wikipedia and...

Generally, the rotational speed of a DC motor is proportional to the voltage applied to it, and the torque is proportional to the current.

Just for future reference. Sorry Splitlip.

Edited by analogkid, 13 August 2008 - 07:55 PM.

[Split]

Searching still applies in the middle of a thread. I've said several times that it's series. I've also told people not to wire them in parallel. Also, if you knew the difference you would know that when I said 14.4 volts that means it's series. Since you didn't know the difference I'm assuming the answer doesn't really matter that much to you.

Also, the motor doesn't get more torque from being in parallel.

Thanks jabulus. You know what I meant, but I edited it anyway for everyone else.

I've received a few questions on this: I have no intention of doing a motor replacement. The motor can handle this load just fine, and running stable with 14.4 volts, outputting far more rounds per second than necessary in a war, I deem it significantly unnecessary.

[wespelarno]

Generally, the rotational speed of a DC motor is proportional to the voltage applied to it, and the torque is proportional to the current.

Yes, but V=IR where
v=voltage
I=current
R=resistance

So increase in voltage gives increase in current. In a DC motor, Torque is proportional to current. But it is also proportional to the number of turns in the motor. The number of turns in the motor is inversely proportional to the current. But an increase in the number of turns of the motor gives gives a greater increase than the assosciated loss due to reduced current. This is assuming no gearing is used. Higher turn motors gives less current but way more torque, hence all the RC rock crawling guys use 55 turn lathe motors (application requires maximum torque) and the rc drag racers use 2 turn motors which allow way more current (application requring maximum rpm).

[Split]

Part 3:
Drum magazine

I'd like to start off with a few quotes on this topic:

Try a unique modification. (Try and think out of the box on a certain gun)

I agree with many of you, this would be very cool if it actually worked. However, if you really think about it, accomplishing that feat would be nearly impossible (and I mean making it work like an actual drum magazine that uses an auto-advance). Maybe for the vulcan, but not the longshot. Maybe this "mod" will be the foundations of a breakthrough in manufacturing a real working drum magazine. Does anyone actually like this?
-A side of nerf

I'll take that as a challenge.

But why in the world would anyone make a drum mag for the Vulcan.

This was well before I had even ordered my Vulcan, let alone had the rotation mechanism broken, and the plunger tube volume tripled.


My goals for this project: breech-less, high capacity, auto-advance, refillable, removable.

Final product:


The body is made from a 5" OD coupler, and the inside is two 2" couplers, one is cut down and attached to the other for a perfect fit.

The part everyone is wondering; how does the auto advance work? I went through a lot of ideas on this one. I tried a stretched compression spring that I kept inside a small tube for a few weeks to make it curved. That one always failed because the spring wanted to turn around inside the chamber. I tried those pen holders that pull it in automatically to try and pull the advancer, which failed because it would pull the advancer only from its base, and adding one that would pull from the top would damage any loaded darts.
I tested out tracks and routes for pulls, but they all failed as well. What I finally went with was a coil spring to actually turn the entire center piece (whereas before it was stationary, and the advancer was the only thing that moved), and attach the advancer to that. The coil spring came from a tape measure, and I was able to scrap all of the mounting brackets to use to keep the piece centered.



In order to accomplish it being breech-less, it had to be airtight. Which made making it refillable difficult. For this, I made a feed slot that will be covered up with tape, which will be replaced after every fill. And to pull back the auto advance, I used picture line that runs through a 1/16" hole covered in E-tape for a seal.


So all of that means that I should reduce the amount of times I have to fill it. So to make it high capacity, I made the size for the chamber a little bigger than 3/4", allowing the darts to stagger. This means that it can hold a calculated 50 shots!
A picture of the staggered darts:


Making it removable was also a fun project. For this, I built the shell in two pieces, one with the back and the auto advancing center piece, and the other with the breech-less brass insert, which sticks out slightly from both sides of the magazine. The brass is made out of the same size as the barrel.


The coupler on the right here, attaches to the blaster.


This is the barrel, nested within a piece of brass slightly bigger than it. When you insert the drum magazine into the blaster's coupler, you then slide the barrel with its coupler onto the front of it for an airtight seal. To remove and replace the magazine, pull out the barrel, which ideally is secured via a rotating attached arm or something similar, then pull the magazine out of the coupler.


To make it secured by more than just the brass, I use cabinet latches:


Here's how it would be installed:


So what do you all think? It's a functioning, high capacity magazine. Isn't that what we've all been looking for?

Edited by Splitlip, 20 August 2008 - 10:09 PM.

[A side of nerf]

I agree with many of you, this would be very cool if it actually worked. However, if you really think about it, accomplishing that feat would be nearly impossible (and I mean making it work like an actual drum magazine that uses an auto-advance). Maybe for the vulcan, but not the longshot. Maybe this "mod" will be the foundations of a breakthrough in manufacturing a real working drum magazine. Does anyone actually like this?
-A side of nerf

I'll take that as a challenge.

But why in the world would anyone make a drum mag for the Vulcan.

It's like it was meant to be split.

Anyway, awesome job, this is phenomenal. This design will be sure to have it's impact on the NIC. I applaud you.
Do you have a picture of it in the gun with the gun put together?

A side of nerf

Edited by A side of nerf, 20 August 2008 - 05:00 PM.

[Ubermensch]

You ripped off the Tommy 20!


Seriously though...



OH MY GOD!!! You are a GENIUS! This is a revolutinary mod, and will truly impact the NIC. Amazing. Congratulations. Wow.



How many darts do you think it could hold?

[Norther of Heaven]

I request, no, DEMAND a video be taken of this machine.

[Split]

I can't actually close my gun right now because I'm halfway through Part 4, and certain things (like the bar you can see in the last picture coming from the rotation arm mechanism) are keeping me from closing it right now. I will have Part 4 up soon, or at least part 4.1. It itself is also a big addition as much as the impossible drum magazine.