The Earthglider

I have had an idea for a unique strategy for a Nerf war for quite some time, and that idea is a remote-controlled car. I just did a unit conversion of its top speed, and it can reach up to 35 ft/second. That's as fast as the entire Elite lineup shoots darts. The Earthglider is also more agile than a person, which is insanely good. It simply is a remote control car with a shortened nerf sword on the front.

An overview of the Earthglider, showing its overall shape.

The Earthglider's ribbed front tires are critical to its agility.

 This is a 1/10th scale remote-controlled car that is stronger than both of my arms put together. It is entirely electric-powered, but I don't have a battery for it at the moment. It has a 50-gram steering servo, which gives it most of its agility. The car doesn't even have brakes, but it has about 10 square inches of tire in contact with the ground, giving it a huge amount of rolling friction. From top speed, it still stops in about 50 feet on a smooth surface. I am looking forward to next spring, when I can actually start using this. :)

It's hard to see, but if you look closely, you can see the steering system inside that little cove in the front.

The Earthglider actually is as fast as a dart fired from a stock blaster. I was actually quite surprised when I discovered this. On my front lawn, it rides the bumps like a speedboat, since it just rides on the top of each bump and then hops over to the next one. Its suspension is actually extremely well-tuned, allowing it to chase down a person on most types of ground.

This picture shows the Earthglder's motor and knobbed rear tread.

Questions and comments will be warmly welcomed! :)

~N-Strike Epic

Rapidstrike Review!

This is going to be an official review of the Rapidstrike. I will be including a general review, some reverse engineering, tactical advice and modding advice.



General Review

The Rapidstrike is an automatic flywheel-type blaster. The flywheels have ben optimized for maximum performance and minimum damage to the darts, making power mods pointless. It is already rather powerful, anyway. It has an accuracy of about a 6 foot radius at 30 feet in stock form, giving it a substantial, but not very useful, range. At 15 feet it gets about a 2 foot radius.
Unmodified, this blaster is most useful as a dogfight/swarm blaster, but its weight and bulkiness make the Rampage significantly better for this task. Even for $40 at Target, this blaster is not quite worth the money.

The best advice I can give is that it's best if you use the jam door to stop the flywheels instead of letting them just coast. Holding down the acceleration trigger with the jam door open will create a closed circuit between the motor terminals, which quickly and forcefully stops the flywheels.



Reverse Engineering

This is a photo of the internals of the Rapidstrike from Coop772:

Safety Switches and Lockouts:

1. Forward Clip Sensor: No power flows when this is released.

2. Rear Clip Sensor: This is a mechanical lockout that keeps the launch trigger from being pulled.

3. Jam Door Switch: This switch is depressed when the jam door is open or partially open. It cuts off power to the flywheels, and also stops them when the door is opened.

4: Trigger-to-Trigger lockout: This is a mechanical lockout that keeps the launch trigger from being pulled when the acceleration trigger is not pressed.

Triggers:

1. Acceleration trigger: This cuts off all electrical connection from the flywheels when it is not pressed.

2. Launch trigger: Gives the dart advance system the command to cycle continuously. 

More on the dart advance system:

The dart advance system is comprised of a motor, a gearbox, a crank, a shaft, and a switch. The switch is depressed once each cycle when the shaft is fully retracted, cutting power to the motor. The switch is wired in parallel with the launch trigger, so when the launch trigger is pulled, the recetion switch does not stop the cycle of the shaft. If the clip is removed mid-cycle, the forward clip sensor cuts all power and the cycle remains uncompleted until the forward clip sensor is depressed.

Modding Advice

The rapidstrike uses C-type batteries for a reason. It has the rating stated on the side of the blaster as 6V DC, 30W. The C batteries have lower internal resistance, and can uphold the high current demand of the blaster without too much voltage sag. I used a 9V rectangular battery for a while, but it made the blaster significantly less powerful. The only significant battery upgrade would be to install a large 2-cell lithium polymer battery (7.4V) with equivalent capacity, but this would be expensive and would only make the blaster lighter.

As I said earlier, the Rapidstrike does not get any benefit from power upgrades. This is because it has already been optimized in the tradeoff between lack of power and dart damage.

So, the only mod I did was an accuracy upgrade, which involved moving the rifled barrel section forward so it could do its job. The rifling actually does work, but only when the dart comes in contact with the side of the barrel. I moved the barrel forward, leaving an open space for the dart to traverse unsupported. The darts would occasionally prematurely veer off-course, resulting in a massive pileup where the barrel used to be. To remedy this, I added about 3 inches of barrel tubing from my old Recon, and that solved the problem. Since the barrel is now farther forward, the darts come in contact with its inside surface, doubling the blaster's accuracy.

Also, I have a personal preference to have an open area of casing instead of a closable jam door, so I removed the jam door.

I added the handle from my Retaliator to the lower rail to help support the hulking mass of plastic and metal that the Rapidstrike is, and I also added my 9-LED floodlight on the left side rail. It seems to be quite effective in blinding an opponent in low-light conditions.

I plan to make a custom high-capacity clip for the Rapidstrike, since it empties its current one so quickly. I have encountered some problems, but I hope I can solve them.

Feel free to comment any questions you may have, and I will reply as soon as I can.

Thank you! ~N-Strike Epic

Epic New Blasters and Breaking the Flywheel Barrier

So, all along, my mission has ben to make blasters that outperform all current stock Nerf blasters. I have succeeded in that quite effectively, and my Firestrike (which I'll probably end up calling "Île de France") is the start of a new mission for me. Now, I am working to get every ounce of performance possible out of dart blasters. One rule: they can't be capable of injury.

So, I have decided to make an arsenal of blasters with muzzle velocities upward of 85 ft/second.
So far, it's just the Firestrike, Pinpoint, and, surprisingly, the Blowsword.

Firestrike

Pinpoint

Blowsword

Also, one project that has been waiting for a long time, since its a bit pricey, is the Earthglider. I built a remote control car that has the agility of a human. it doesn't even get to 22 mph, but it can get up to 15 mph in under 2 seconds. So I put a shortened nerf sword on it, and thats pretty much it. One problem: I need a new battery, since my current one didn't last all that long doing those repeated power surges that are required during acceleration. It's a 500 watt system, and that battery just didn't quite hold out. Some ozone formed inside its cells, and that raised its internal resistance, which lowers its performance even further. I'll probably jack it up to an 800 watt system when I get a new battery for it. This is not a cheep thing to do, the right battery is around $60.

Also, I got myself a Retaliator and a Rapidstrike. The Retaliator has the AR removed and a heavier spring, as well as a different barrel extension. I really got it for the stock barrel, which I put on the Pinpoint. That really pays off.

My rapidstrike.

The Rapidstrike has a 9V upgrade already, and that really didn't do all that much. Eventually, I'm thinking of adding a secondary flywheel set that re-accelerates the darts. I'm not 100% sure if it would work, but I'd say it's worth a shot, at least 90% sure. This would probably just involve getting another Stryfe and extracting the flywheels. Since I want to double the kinetic energy of the dart, that requires some physics calculations.
Let:
S = Speed
Ke =  Kinetic Energy
V = Voltage to Motor
I = Current
P = Power
R = Resistance

First, the two statements that are always true in an electric circuit:
P=VI
V=IR
From these,
P=VV/R
And Newton's Second Law:
Ke=0.5SS
An approximation about the motor:
S is proportional to R

So, we can say:
P is proportional to VV/S

Wait... oh yeah, this one makes it all really quick:
The square of the speed is proportional to the voltage.

(That one I came up with while working on the Earthglider.)

So, adding Newton's second law of motion back in, we can say that:
The voltage is proportional to the square of the speed, which is proportional to the kinetic energy present.
So, since V is proportional to Ke, if I want to double Ke, I should double V.

For those who skipped all that, the second flywheels run on 18 volts.

I just published my response to the technical problems (namely, friction heat melting dart foam) that are the reason that flywheel blasters are so limited in performance.
This is a pretty big breakthrough. The NIC needs to start developing this technology of multiple flywheel sets. It really is going to pay off... seriously, people, get on this. Flywheel blasters and their semi-auto/automatic abilities just need a performance boost. So who's with me?

Pistol Mania!

I haven't had as much time on my hands these days, with school and all that going on. But i still have weekends mostly free, and so I ride bikes and do Nerf mods. At least I have that much of a life.

On to today's topic: Pistol Mania! From left to right: RADS12, Vortex Proton, Firestrike, and Hunter.

And I didn't even get the Kabam in the picture. But that one is basically small. Like as small as physics would allow. It really isn't much more than a Jolt on steroids.

Well, on to the RADS12: It has 12 shots on the front, as you can see, and 4 sets of 3 barrels. It has a lot of things just for show when it comes to reloading, but it can still reload faster than the flywheel blasters. Who cares about automatic and semi-auto? I can reload my own blaster, thank you. It usually works better, too.

On to the Proton... I have been using it to test out the Vortex discs, and I have come to the conclusion that the XLRs are actually worse. Longer range, maybe, but they fly a lot like frisbee golf drivers. The standard discs fly much straighter. Discs in general are a real pain in the first place, since they're very sensitive to wind.

I'll go with the Hunter first: It is extremely accurate, and more powerful than a stock Firestrike, and it also holds more ammo. It is slightly bigger, however, but that really isn't a problem. In fact, the Hunter has space for two hands and a padded mini-stock on the back.

My Firestrike, however, sends the dart flying at 90 feet per second, and classifies itself with the high-power Nerf blasters. But, of course, I have already modified it heavily. It is not quite as accurate as the Hunter, but the Hunter clocks around 30 feet/second.

Who doesn't love a good Firestrike?

The Hunter, having fallen behind my other blasters, might be for sale sometime. But not yet. 

And to answer that pressing question about why the Firestrike was so good, in stock form it really isn't that good. The two darts on the front are very nice, and it is very fruitful to modify because of its massive cylinder and simple power transfer.

Vivé la Nerf!