So I have a Long Shot with a Remedy Metals powertrain kit in it with a cut down [k26] and the stock spring. I have not been able to find a dart that the kit likes or flies straight (as possible). The kit doesn't like full length darts made from solid 1/2 inch foam (just doesn't make it out of the barrel). I have tried half length slugs with the ACE hardware foam, they fly fine, but I would like to use an 18 drum with the kit. The elites and streamlines just ain't accurate (no **** right?) even with clayed or hot glue tips. My buddy has some of the velocity tag darts and they work WONDERFUL, but they don't seem to be able to reply to any emails or facebook. Is there anybody out there that knows what else I can do or are there any other companies producing a dart that will work in a stock clip system? Anything will help, I just want to be able to use this kit to its full potential!

I haven't tried it yet, but try ordering from this place, I think they're a branch of Xplorer Blaster Parts:
http://www.survivorfbu.com/

Edit: this is also important data to consider when we're testing against the range caps we've imposed in NJ at indoor wars. Based on this data, most people will actually be able to get their primaries under the 75-80' caps as long as they aren't trying to show off. We should probably just switch to a velocity based rule, but we could also set up a more consistent testing rig with a lower cap.

A velocity rule would be much more consistent and be more conducive to safer blasters, but it's my understanding that most people don't own or want to pony up for a Chrony.

I'm working on a chronometer right now using an Atmel chip and and LCD display, if I provided the code, or made a version that was compatible with the cheap (10 dollar) Arduino Mini Pro, would people be interested in building their own board or buying the premade board? Should be cheaper than a standard Chrony. my current version is with surface mount parts, FWIW, but a through hole version could easil be made. just would be bigger.

^Gotcha, I figured as much haha. Gotta do what you gotta do.

I have done that, but I don't remember posting anything about it. I mostly just wanted to make sure that I was staying flat.

Great chart, Koree. That is actually going to be helpful for a project I am working on. Could I get a copy of the spreadsheet data from you?

I just remembered seeing it in passing. You posted a pic, too? Wasn't a thread or anything.

Great data. Very illuminating. Why not just tape a level to a blaster? I remember someone here did that and was really surprised what a PTG shot was. Was it Draconis? I dunno.

Oh, not to threadjack, but I use one cell LiPos. I am currently using a 4300mAh Gens Ace hard case LiPo. Gens Ace is a good brand, if you want a battery that is cheaper, just get something with less current supply.

Feel free to PM me to continue to conversation.

^One guy at Armageddon sprayed his darts, but he very peculiar foam, seemed to have air gun fit in CPVC? If you remember, his foam was pink and silver, I believe, with single BB glue domes.

Best Materials sells their beige foam by the foot here, so you can order whatever length you like. This stuff is supposed to somewhat fat, so you may have to use different barrel material. But it's also supposed to vary quite a bit in the roll, and you could also stretch it to fit whatever barrels you have.
You could also purchase some of Mod Man's red foam.

Does Mod Man even still sell red foam?

No idea, you should look up the specs.

I'm not telling you not to use RM2s, just that they aren't really too much of an upgrade. Additionally, they can suffer brush failure rather quickly if you try higher than 9v.

Haha, yeah they even had some of your old ones, Shmme. Just were in the community bin.

Trustfires/Ultrafires usually do not have the current supply they boast, but if someone has heard otherwise, feel free to correct me.

To find out how much current you batteries can supply, you must know the discharge rate.
Then check out this page to learn how:
http://nerfscience.b...-page_5065.html

At 8.4V, they will need around 4-5A at stall. The batteries you linked can likely do this. However, do not expect a huge increase over stock.

Roboman makes some with 5/8" OD aluminum tubes and PETG.


It's a sound practice in theory, the way to think about it is just by applying basic physics. With a tight barrel fit like CPVC in a spring, there is a certain amount of pressure required to build up to allow the dart to break the coefficient of static friction applied by the tightness of the barrel fit. After this, the amount of the friction the dart encounters while moving is much smaller - this is the coefficient of kinetic friction. Ideally, we want this to be as small as possible. This is the idea behind telecoping/efficient/transition barrels.
Now, does it make a significant difference? Not sure. I am sure there is a trade off between a lower coefficient of kinetic friction and the amount of air escaping along the sides instead of pushing the dart. There's also something to be said about the decreasing force of air as the volume behind the dart increases, decreasing pressure behind it.

The basic idea is that we use tight fit barrels for springers because we need the system to build up enough pressure to generate enough kinetic energy to break the coefficient of static friction.

In an air blaster, the tank stores air, meaning that the air in that system is already at its maximum pressure. A loose fit will take the most advantage of this stored energy.

Try cutting through the glue.

I don't recommend using RM2s. If you do, don't over volt it past 9v.

On another forum, they say the resistors are inductors, but they look very much like 1Watt Resistors.

Those are inductors, they exist to smooth out AC ripple. They serve no purpose in our circuit, as we don't care what kind of noise the motors can introduce in an electrical signal, as we have one.

Those are locally stored. You need to upload them online to something like imgur.

Stock elites have amazing flight dynamics. Agreed that at high velocities they are wildly inaccurate, but at lower speeds they outperform any NiC stefan I've ever used. That is the true measure of flight dynamics. Any weighted peice of foam we slap together will fly strait and true when we back them with incredible velocities, but the stock elite dart was engineered to perform wonderfully at lower speeds and coax as much range out of lower powered blasters as possible.

But any decently powered air blaster will have higher FPS than Elite blasters.
The Elite dart works well because most of the weight is in the front, and it's a good amount of weight for lower power blasters. If you use a stefan with more weight in the tip, of course it will not perform as well in a lower power blaster, the blaster needs to put more energy behind the dart to make it fly further. Heavier tip means it needs more kinetic energy to move the same distance.

But even at 5-7kg spring loads in Elite Blasters, Elites are pretty inaccurate, IMO.

Yes it's normal, there's a diode drop, for some sort of pre-rev mode.

If you search, it's been documented that people have brush failures at higher than 2s for RM2 motors.

You should not be using trustfires with these motors, anyway, as they cannot supply the current that the motors ask for at high voltages. This makes for slower recovery/start up time.
Trustfires can barely supply 2A at all.
Also, their voltage when under load is poor.


Remember, voltage supply is not everything, you must also consider the current discharge rate of batteries.
Check out the article on my under either the Rayven guide or tech articles, infamous goes over it quite a bit.

There is no safety issue, as long as you are using batteries correctly and making sure they never drop below their nominal level and overdischarge. I have never had any problems with high current setups, and I recently helped build a robot where each motor consumed 100A at stall. No issues whatsoever.

One thing I have to say is that I actually really like the darts that come with this blaster haha. The black foam is great. Buzz Bee needs to release a 100 pack of these EXTREME darts, I would buy that.

I can back up Duke's range claim however. Tank expanded, 8 pumps, this thing gets 100+ flat no problem with an 8" CPVC single barrel. My pump shaft nearly broke where it connects to the handle, so it is necessary to reinforce it as Duke pointed out.

Contrary to popular belief, I'm not just making shit up.

?
ShaNayNay's is tank expanded. It didn't sound like yours was.

ShaNayNay, what did you use for your tank expansion? Rough estimate of air volume?


FWIW, I think stock elites have terrible flight dynamics. The tip is so light that at higher FPS, they do not have stable flight at all. They swerve, for sure.

http://nerfhaven.com...iew=getlastpost


Not sure about where to get it in the midwest, otherwise. Kmart is the only store here that carries it. Drop about 20 mins southeast for one, just happened to already be heading that way.

With 5 pumps, too, though? I mean, maybe because it's higher pressure, because it's smaller...I mean, Supermaxxes hit 100' and they have a smaller tank than a Panther....:0 I dunno haha.

Like I said, I'm getting over 100ft with stock streamlines and 5 pumps.

Good luck

Really? With the stock tank? I'm about to pop an older Panther in my Air Max 10.

Double posting, the perils of using a tablet.

Since I have this post slot, sorry, does anybody know where can I find an AirMax 10? My local wallyworld and Target only carry the six and the one.

Just bought one an hour ago from Kmart.

Fair enough.

Venom's check valve is still pretty viable. Didn't Ryan also use one in his fairly recent extension spring/later blaster?

I also think of it cost versus time, though. I like to tell myself that my time is pretty valuable :0 haha.

What's the point of making a check valve? Nylon check valves are pretty cheap on McMaster, is there a reason why I shouldn't use one? srs question haha.

Clearly, a wire has been accidentally disconnected, sir.

BTW, if you decide to mod it, don't use a soldering gun, use an iron. There's a guide on soldering on my blog, linked both in the Rayven mod guide and the technical pages part.

Don't worry, there are plenty of us experimenting to find the most effective way to do tank expansions for the new versions.

Yeah, I've been looking at it, just trying to figure out what to use for the side wall/ends, if that makes sense. Fat PVC pipe gets expensive fast!
I'd like to be able to fire some Buzz Bee missiles with this thing if possible haha.

The issue is the spring, just don't use the stupid battery tray contacts hahaha. That's all it comes down to.
Or at least solder to the metal plate and not the spring. Or solder a crap load of wire or something to the spring to increase the area. That will reduce resistance.

As far as trustfires doing that, I would say that's more due to overdischarging the cell or shorting the battery. Trustfires have terrible current discharge rates. Well below what most powerful motors need at stall. When using any kind of powerful battery, you should always install a simple LED voltmeter to prevent overdischarge.

.1 ohms is pretty huge, IMO.
I doubt that is what it is, though.
I don't know the dimensions of the spring, and I don't really care too much, but here's some math from a flashlight forum:

Looking at #24 gauge bare copper wire which has almost the same
diameter as 0.022 inch wire, the resistance for 1000 ft is 20.8 ohms.
For 1 foot, it's 0.0208, and for 1 inch it's 0.001733 ohms.

The length of the helix is approx:
L=4.5 turns times 0.375 inches times pi=5.3 inches.

The increase in length due to the helix over the
circumference is only about 0.2 percent, so this increase
will be ignored.

5.3 inches times 0.001733 equals 0.00918 ohms total for a copper spring.

Knowing that the resistivity of SS is about 42.4 times higher than
copper, multiplying the total resistance times 42.4 gives us an
estimate of the total resistance of the SS spring.

R(SS)=0.00918 times 42.4 which equals 0.39 ohms total.

This number indicates something went wrong with the previous
calculation done in the previous post. I suggest checking
it for an error involving the conversion factors. Since rho
is given in ohm-cm i suggest working entirely in cm and cm^2
and redo the calculations.

That should give you an idea, at least.

You are underestimating stall current, meaning the current that a motor uses when it starts moving. It can be pretty big, depending on how many volts you're feeding the motor. As you increase the voltage, the current demanded by the motor increases too.

It's a pretty well documented phenomenon in in flashlight forums. MY WIRE wouldn't catch fire under those circumstances, I use teflon insulated stuff, it's pretty tough stuff. Also, my spring HAS gotten hot enough to catch flame. I had to put out my Stampede - this happened to me. Why doubt me?
I don't know anything about yours. I've used slightly higher gauges of this teflon insulated wire in robotic builds that consume over 100A at stall current. And it was fine.
You might be fine because Trustfires are honestly terrible batteries that cannot supply the current that these motors need. They have a poor discharge rating. If you use something that actually gives the motor what it needs, it is a different story. My rate of fire is higher than most 4s (16.8v) Stampedes I have seen with a similar spring load (I am approaching 10-11kg).

Are the dimensions of the spring similar to anything that we can replace it with?

Short darts require less FBR to make, are easier to handle, are easier to load, and you can fit more of them into a tube magazine. Homemade darts were originally the same length as stock darts, but over the years people have made them shorter and shorter as it has become clear that the extra length was not really contributing all that much to accuracy.

Ah yes, capacity is another point, of course.

I think there's a reason why drag has become less of an issue, in that a dart head now is significantly a greater amount of mass compared to the dart itself, especially since it's shorter, so the forward vector is much more dominant than any other direction.

It's not about making stefans, I'm saying that dart length is not the sole reason why a projectile gets increased performance. We use shorter darts because they have less drag, but they won't be more accurate. They may fly a bit further, though. It's a tradeoff, I would think, because darts are drag stabilized.

I was thinking, dart length is one of the reasons streamlines/elites fishtail at long ranges, right? So would cutting off the bottom half of the dart and just using the half with the head on it increase performance in non-clipped blasters such as the crossfire, strongarm, or triad? If this is completely wrong, well, shows how little I know about how darts work. Thanks,

The Dart Blaster

I'm pretty sure I'm still drunk but actually the main reason for unstable dart flight is that there isn't enough forward focused weight in elite dart. Dart length only contributes to drag, but if you have a dart with stock length, but with more weight in the tip, I'm pretty sure flight will be stable.

Silicone dome darts using a 3D printed mold. Work in progress.


More info here:
http://nerfscience.b...-dome-dart.html

I always wondered how you got the insides so clean.

What printer are you using?

Right, I'm familiar with the process, I have one for prototyping at work.
Do you have any support material on these?

Any idea when you'll have more wyes in stock?


EDIT: Woops, thought this was in the sales forum. My bad.

Ah, I see.

Yeah, actually I'd like to know how much there is to modify the shell for rear loading.

I'm using unprotected (gray) trustfire batteries.

Testing the solder joints, they provide negligible resistance alongside the metal plates, though I don't know if this is relevant.

When firing with 6 D batteries, the voltage across the two panels on the battery sled dips slightly from 9 to about 8. When attempting to fire with the trustfire batteries, it drops to 0 volts.

That is a VERY clear indication that your AA tray does not work, either because of your solder, or because of the tray.

Dude, as already pointed out, your battery connector is connected to the battery sled in the wrong polarity.

The black wire should go to the spring.
The red wire to the tab.

There is no thermistor in the battery sled.

It should not matter if you solder the wires to the spring and tab, so long as the join is good and clean.

No other electrical mods are needed unless you want to remove all of the locks.

Wrong, the spring has a high resistance, and should not be soldered to. Excessive current draw can cause it to light on fire. This is a well documented problem with battery springs. Ideally, battery trays shouldn't use springs at all.

Break what to the what? And why? Sorry, just not clear as to why I shouldn't do something.