Saturday, March 4, 2017

NERF Hailstorm: Rival Kryptek

Seeing videos of people converting their nerf rivals I had to give one a shot.  Since C and D batteries are so passe I first replaced its 6 C cells with 3 8000mah lithiums which allows this thing to spit out 12 rounds in well under a second.   I modified the trigger to be a two stage trigger pull half way to spin up the flywheels and a high power ducted fan for the feed tube, wait a quarter second then pull all the way to open the gate and unleash nerf hell.  When this bad boy spins up you know its time to duck and cover. The balls also dont feel very good when you get hit so WEAR SAFETY GOGGLES.

I havent spent enough time to work out the feed issues with the backpack. At present Im thinking some sort of cork screw to prevent clogs.  A project for later...

I decided to paint it with a kryptek style staying with light blue grays or silvers. Other than the backpack clogging issues, and that there is no reasonable way to play with others with this, I am quite proud of this bad boy.  Next I need to develop a filtered vacuum cleaner to pick up the hundreds of balls this baby can fire in a minute. 











Parents get sabers too!

It was unfair for the kids to get sabers so the wife and I get sabers now.
I have a light staff under way but at this rate itll be another 6 months.  Too many other projects.
She gets one that looks vaguely sith like with scratch marks for grip while I get two black and silver handled  more classical style.  Both handles are aluminum with a mild level of polish and the grip black is a duracoat for maximum durability.  




She got the bight teal on the top while I got an aqua and ice blue.  Hers is brighter because its a fixed LED while mine are RB and RGB. 

For the internals I used lightsaberos for arduino as found many places on the net.  Modifed the code a bit, and after a lot of playing figured out a stack which allows an arduinonano, a sound amp, an mp3 player, voltage regulator etc all on one board.   later I further added a 5V boost because on powerup with high power blades we often got a brownout on the boards causing a reboot or glitch state.  a buffered 5V boost allows the arduino to stay powered at 5V even while the batter takes a large initial hit. 

Further powering a few hundred milliamps up to an amp for the LED array takes a fair amount of fet power.  I milled aluminum heatsinks that socket some FETS and allow a set screw in the handle to press the heatsink into contact on the ID of the lightsaber aluminum tube turning the entire handle into ground and a heatsink.  Otherwise these fets overheat and blow within 30 seconds.  It turns out using red is even worse because it has such a low potential drop  compared to blue and green that the fet has to dump a ton of power.  Thus why people making red blades often run half of their LED's in series with the other half.  Blues have such a nice high voltage that the fets down have to dump much heat.  The quad fet below is powering an RGB saber. with two fo them running the Red led's.  The 6 fet sink runs the blade in segments with a common ground (or anode, I forget which) making the blade power up in sequence.