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#326393 The BEST upgrade motor for the Stryfe (after extensive testing) is...

Posted by azrael on 05 February 2013 - 07:45 PM in Modifications

Typically, LiPo batteries are more expensive than any other type, and require a more expensive and singularly useful charger than any other type. At least with NiMH batteries, you can use them in your television remote and wireless mouse. All he is saying is that he doesn't see the need for his purposes. For new people buying one type of battery to use in all of their blasters? Sure, LiPos make sense. If you already have Li-Ion batteries, like Trustfires, then use them. The information I found within the independent reviews of Trustfires on DX indicated that the over current protection would allow 4A draw through full discharge. That's probably fine.




You'll notice that I gave both.

I assume you mean voltages while measuring these currents. The stock Barricade measures 4.65v at the batteries with the switch off, drops to 4.0v and climbs back up to about 4.4v at full speed. The modded unit shows 4.75v with the switch off (I don't know about the discrepancy, that's weird), drops to 3.05v while accelerating, and comes back up to 4.25 while running full speed.

I suppose it is possible, but not in the milliseconds that it takes for my DMM to read. Also, is this the chart you are referring to?

Posted Image

Yes, that's one chart I saw. It shows 4.93A for 5V there, but on another site, it said it was 4.5V. Motor specs are pretty hard to find on the internet haha.
Stall current happens pretty quick, I think. I know you measured peak current draw, but I don't know if a multimeter can display it quickly enough without averaging out the samples.
I just work out the rough math for stall current based on current charts and increasing voltage (typical Tamiya specs are at 2.4V).

The voltmeter I put into my gun is pretty crude, but with a battery measured at 4.2V out of circuit, it shows a I think 3.6V when rapid firing, and just 3.9V when just running or after one or two shots. If I press the acceleration button with no clip, it reads 4.1V still.
Just to give you my experience with the LiPo.

Those sound like Ponies. Also, ridiculous requirements. Maybe that's a little much?

The Plasma Dashes don't sound any louder than an overvolted Rayven at 16V, I think. YMMV.
Also current requirements are pretty typical, for more powered up motors.

That said, I think the Plasma Dashes actually run too hot, temperature wise, for use in an plastic enclosure like this haha.
The Mach Dashes I got seem much more manageable, and are pretty close to the Hyper Dash 2s in terms of power requirements.

I am using standard alkaline AA batteries (Rayovac) rated at 1.5v, just do dispel whatever you are trying to cook up here.

How long do the motors take to spin up or recover on the Alkaline?
Not trying to "cook up" anything here. I want an awesome gun as much as you guys haha. I just want consistent results to decide for myself. I'm hearing different ranges with essentially the same motors in a similar setup. There shouldn't be a 40 foot difference in the two sets of results. Just saying.

NiMH is capable of a little more current then alkalines but the biggest difference is that NiMH will have a longer charge life at the high amperage draw then the alkalines will.

You got 70-80ft ptg using what? Stock motors on stock voltage? Trustfires? Something else? I only got 60ft on stock motors and AAs.

The problem with the Tamiya Dash series of motors is that they're 3v motors. Any 3v motor will require twice as much amperage to do the same work as a 6v motor. The Dash motors are built for that kind of amperage of course but as you already know you'll have to use something other then AAs or Trustfires to supply that current.

Just saw this post.
70-80 feet using Tamiyas and a LiPo, like I said in the thread I have which you posted in before haha. Sorry for assuming it would still be fresh in your memory, that was my mistake.
I don't think the Stryfe can do 60 feet at stock. I didn't test mine with the stock setup for long, but that seems to be the average range of one overvolted to 12V, based on other tests I have seen conducted.
Are you actually measuring? Or just guessing? I thought mine was hitting 90, but upon measurement, it was more like 80 at peak distance, with high 60s and 70s on average.

Also, I brought up the current thing because based on the specs, like in the chart posted by Draconis, current draw is reaching a level that could potentially burn out the stock switches, even with your voltage setup. It's just a word of warning.



#326485 The BEST upgrade motor for the Stryfe (after extensive testing) is...

Posted by azrael on 07 February 2013 - 01:00 PM in Modifications

I tried the Tamiya Hyper Dash motors mentioned in another thread and the motors mentioned in this thread are significantly better for our Nerf use. The Tamiya motors seemed to have a higher RPM which would give a better first shot, but the follow up shots were absolute shit compared to these or even the stock motors.

I posted a video where you can see that my shots are pretty consistent, don't know if you saw it in my thread.
Did you perhaps leave the thermistor in? That would make subsequent shots worse.


Any range measurements for these motors?



#326385 The BEST upgrade motor for the Stryfe (after extensive testing) is...

Posted by azrael on 05 February 2013 - 06:13 PM in Modifications

Sorry bud but NiMH eneloops ≠ trustfire LiFePO4 no way, no how.

I don't like your insinuation that I've been misleading. For the record the generic brand NiMH AAs I have work just as well. Alkalines will give the same dart distance but they run out of juice faster. I haven't tried lithium AAs yet but I'm sure they work as well or better then the NiMH.

As for 90ft ptg, I got what I got and found a decent motor in the process. Polulu.com had over 60 in stock when I made the OP and last I checked they had 5 in stock. That's plenty of folks that will be able to report their results. I'm sure someone will post a vid.

I'm pretty sure Alkalines do not have the same current capacity as a NiMH battery. High stall currents might not be able to be done by standard AAs, thus, recovery time increases.

It's not that you were misleading, but more so that it wasn't clear. No need to take offense.

90 feet is just pretty high, I'm just looking forward to some proof. So far my Stryfe has got about 70' PTG, with a few hitting 80' maybe. If those motors are all that and a bag of chips, awesome.
I'm gonna try some Tamiya Mach Dashes in a few days. :)



#326374 The BEST upgrade motor for the Stryfe (after extensive testing) is...

Posted by azrael on 05 February 2013 - 04:09 PM in Modifications

I haven't measured, and I have no idea how long AAs would last during a nerf battle. I don't nerf battle at all. I'm too old for that stuff. For me this is nothing more then a fun novelty that I harass my wife and our cats with. For my purposes a set of 2000mah Eneloop AAs last a week. So they're not burning through batteries like fire through tissue paper or anything. How big of a deal is it to swap batteries between rounds?



Using a LiPo requires special chargers, special battery storage, modifying the battery compartment, carefully monitoring battery usage, etc. It will be fine for some people and there's definitely a battery performance advantage to those who go that route. But AAs are simple, easy, common, cheap, familiar, etc. I suppose among this crowd trustfires are similar, especially if a person already has them on hand.

I really hope the trustfires work. If the trustfires can deliver the current for these motors and the extra speed doesn't push the darts past their aerodynamic stability I think 100ft+ ranges are possible.

You're using Eneloop batteries, which come in the AA package. But the way you say AAs, you make it sound like you're using standard AAs - which you're not. Eneloops are pretty much like a Trustfire. Just NiMH instead of Lithium Ion. You're just not overvolting it since Eneloop is 1.2V, whereas a Trustfire that nerfers generally use are 3.7V.
In fact, Eneloops can discharge more current than a the common Trustfire, I'm pretty sure.

You make the argument for a special charger, but rechargable batteries like Eneloop and Trustfires need one too. Granted, the a LiPi station is more expensive. I had LiPos lying around, and I have access to a charger. I never tried Trustfires because I didn't want to buy a new setup.


Another very important thing to remember that you guys are not taking into account is stall current.
You guys seem to be measuring continuous current draw, but motors need a lot of current to accelerate quickly in the beginning. That's why I decided to use a LiPo.
The Plasma Dash motor, for example, should have a stall current draw of around 10A. That's something a Trustfire will never be able to supply. And that's just one motor.
The Hyper Dash 2s I used should have around 4A stall current.
I just looked it up, these Solarbotics have a stall current of almost 5A at 4.5V. I expect the recovery time of these is a bit higher than stock motors.


I would like to see a video of 90' PTG ranges, the specs I was reading don't seem that crazy.
Also, I'm pretty sure the stock switches are only rated for about 2A, maybe 4A. Be careful with that stall current...

Draconis, I would also check the voltage when you're getting these voltages. See how much it drops when pulling a lot of current.



#326347 The BEST upgrade motor for the Stryfe (after extensive testing) is...

Posted by azrael on 05 February 2013 - 01:08 AM in Modifications

I don't see what the big deal is with having to use a LiPo.
Trustfires just don't hav the current supply for many of the more powerful motors out there. It's a fact.



#327510 The BEST upgrade motor for the Stryfe (after extensive testing) is...

Posted by azrael on 03 March 2013 - 12:49 AM in Modifications

Bobololo, it still happens with plastidip, but I would say to a lesser degree.



#327512 The BEST upgrade motor for the Stryfe (after extensive testing) is...

Posted by azrael on 03 March 2013 - 12:53 AM in Modifications

Plastidip eventually wears off, though, and the dart buildup does still occur so any balancing is probably going to be temporary in a Stryfe or any flywheel blaster, really.



#332335 The BEST upgrade motor for the Stryfe (after extensive testing) is...

Posted by azrael on 26 July 2013 - 03:43 AM in Modifications

Not that insane, the Tamiyas I use are like 23k+ RPM. Dunno exactly since they're slightly overvolted.



#332399 The BEST upgrade motor for the Stryfe (after extensive testing) is...

Posted by azrael on 28 July 2013 - 12:52 PM in Modifications

Have you guys been reading about the failures? Just wanna make sure you're aware that many people have had brush failures with these motors.



#329196 The BEST upgrade motor for the Stryfe (after extensive testing) is...

Posted by azrael on 30 April 2013 - 10:37 AM in Modifications

Where did you get this? Looks very different to the numbers listed on Pololu and other sites...



#329182 The BEST upgrade motor for the Stryfe (after extensive testing) is...

Posted by azrael on 29 April 2013 - 08:15 PM in Modifications

1. The RM2 motor specs for 6v so you're giving patently false info about that.
2. I did measure fps using a ballistics chronograph and they definitely are stronger then the stock motors, volt for volt. Compare apples to apples.

Lying about what? I've seen the table for 1-9 volts, and even at 3-4V, stall current already exceeds the current supply limitations of a Trustfire/NiMh. You can definitely run them higher, but apparently the brushes are complete shit, so I don't think it's smart to run them that much higher.

What numbers? I've never seen any real numbers from you.
torukmakto gave me numbers.
At the same voltages, it was maybe a 2-5 fps increase from stock. I trust him a lot more than you, he's a reputable nerfer on HvZ forums.



#329095 The BEST upgrade motor for the Stryfe (after extensive testing) is...

Posted by azrael on 27 April 2013 - 02:37 PM in Modifications

Tamya Plasma dash motors. SG nerf uses them to compare stock motors. I did a thread on them. Just search "Nerf gun motors, problems and solutions"
They are very good, I use them I'n my barricades. I run 9v on them and they work fine and have been for over 2 months now.

Lol, you're not providing them with the current they want. I guarantee you that if you run them with the proper battery, it will have very different performance. I have used them, they are RIDICULOUSLY fast.

Trustfires and NiMhs do NOT provide enough current for any of these motors. Even the RM2s.
The RM2s should probably only be run on a 1s system.

But torukmakto did some FPS tests, these don't seem to be any better than stock anyway. Duke_W has seen the same reports I have.


If you do use Plasma Dashes with the right batteries, you will need a better switching system. I haven't gotten to using a relay system yet. Will soon, after some robotics projects are done.



#326237 The BEST upgrade motor for the Stryfe (after extensive testing) is...

Posted by azrael on 01 February 2013 - 06:08 PM in Modifications

Neat. Might get a second Stryfe just to compare it.



#326241 The BEST upgrade motor for the Stryfe (after extensive testing) is...

Posted by azrael on 01 February 2013 - 07:04 PM in Modifications

What kind of torque does it have? Any numbers?



#325122 Strongarm AR Removal

Posted by azrael on 07 January 2013 - 01:11 PM in Modifications

Very nice. Nerf made some good improvements to the Maverick design, like the improved seal.

What kind of spring looks like a good replacement for the stock one?



#332823 Nerf Mega Centurion Mod

Posted by azrael on 09 August 2013 - 05:05 PM in Modifications

TBH, I don't see why a reverse plunger is all that different from a normal direct plunger. The reason why the reverse plungers generally suck is because in stuff like the Maverick or Recon, they are moving a very small amount of air. That's why those blasters have small ranges and small potential for mods.



#333489 HammerShot Mod Guide

Posted by azrael on 27 August 2013 - 01:09 AM in Modifications

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



#327925 Nerf Elite Strongarm Clip Mod

Posted by azrael on 12 March 2013 - 03:08 PM in Modifications

One would expect that you must apply approximately 59 Newtons to prime it.

Ha ha. thanks for the conversion of units. :P
I was hoping to see if maybe I just installed it wrong or something, or maybe my gun is messed up. The sliding mech doesn't catch on the tube anymore really, or at least it pops off due to the amount of force the spring exerts.

There's just been a couple of issues I've had with mine, tried rebarreling one barrel with the polyester tubing on mcmaster, and that didn't go over well, actually resulted in a loss of range - possibly due to the fact that the plunger only forms a temporary seal with the barrel. But I've seen people doing it with CPVC, so I dunno what's up.

Welp, just kinda rambling now.



#327878 Nerf Elite Strongarm Clip Mod

Posted by azrael on 11 March 2013 - 04:57 AM in Modifications

How hard is it to prime with the 6kg spring? I found it crazy hard, really easy for the priming mech to not catch the plunger, too.



#325618 Stryfe Modification - Something slightly different...

Posted by azrael on 22 January 2013 - 04:26 PM in Modifications

If you don't mind me asking, what are the specs on the single cell LiPo you ordered? I'd assume it would have to be ~4100mah to keep up with Plasma Dash motors.

6000mAh

I'm thinking people are melting darts because the flywheels aren't gripping them well, so the darts end up being rubbed the wheel several times before being pulled forward correctly.
The Plasti-dip is what works against this, making it more efficient, and this is why I haven't melted any darts.

As far as why it's quieter, I think it's the quality of the motors. They're probably more balanced.



#325590 Stryfe Modification - Something slightly different...

Posted by azrael on 21 January 2013 - 11:31 PM in Modifications

16v Stryfe on stock motors is starting to melt darts.

Whoa. I certainly haven't seen that.

My friend has noticed scuff marks on the tips of his overvolted Rayven, though.



#325629 Stryfe Modification - Something slightly different...

Posted by azrael on 22 January 2013 - 10:10 PM in Modifications

Be careful your flywheels don't come apart at those high RPMs. Probably not too much to worry about while the blaster is assembled but when you have it apart on the work bench testing remember to wear eye protection just in case.


they snap on, I don't think there's much risk. ;)



#325583 Stryfe Modification - Something slightly different...

Posted by azrael on 21 January 2013 - 09:56 PM in Modifications

Based on the battery's label, and paralleling it, I'd say, 40A continuous, 80A burst.

Also gonna put a mini voltmeter in there so I don't run it below 3.7v.



#335883 Stryfe Modification - Something slightly different...

Posted by azrael on 09 December 2013 - 03:01 PM in Modifications

Sorry for the necro, but I would like to know if 3 AA nimh batteries would provide enough current to run the motors. I'm planning on putting these in my rapidstrike.

No idea, It's very hard to find discharge rates on NiMH batteries. The mod on the nerf reddit has done it using eneloops, and the spin up time isn't great. Try using 6 - 3 in series paralleled with another 3 in series.



#325573 Stryfe Modification - Something slightly different...

Posted by azrael on 21 January 2013 - 07:49 PM in Modifications

This is a quick run through of what I did to a Stryfe I picked up yesterday.
I don't think this is something everyone should do, as technically, what I did is dangerous. There are safer ways to do this, but I was lazy. I'll elaborate later in the post. As electrical engineers, we know what we're doing. mostly, haha.
This is not a tutorial, and this is not in depth. We did this rather on the fly, and will be doing the same process later this week with a Rayven.

What we used:
18 gauge wire, red and black
Plasti-dip spray paint
Hakko FX-888 soldering iron
lead free solder (harder to use, but the fact that it melts at higher temperatures is better for our purposes here)
Tamiya Hyper Dash motors
8.2V LiPo Battery and connectors

I wanted to mess around with an electronic blaster, as opposed to air powered and plunger type ones for a change. A friend of mine got the new Elite edition of the Rayven, so I picked up the Stryfe.
He happened to have some Tamiya Hyper Dash motors lying around from a quad copter project, so we decided on a whim to put them in:
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Notice there are no caps on these motors, as on stock ones. They're not necessary, since there is no signal here. We don't care about their effect in a system like this. Just wanted to point that out.

I have read someone tried Tamiya motors in a Rayven before without success. To that guy, I say, "wat a nub". I remembered reading that he kept overvolting it to get the motors started, and even then it didn't work well.
That's not how to use Tamiya motors. They run at a maximum of 4.5V, but draw a lot more current. So that would be one Trustfire in this case - 3.7V. Not good enough - it can't supply nearly enough current. I'll explain my approach later.
Notice I also left the Thermistors out. Why? These motors run hot! Those thermistors will be doing their job too well. Plus we KNOW we're running at a safe voltage here, so there's no chance of burning them out.

Also, I use teflon insulated wire, in this pic, should be able to handle the higher current demands with no problem.
I remembered a cool trick Coop did to his flywheels on his Stryfe, namely painting them with Plasti-dip. Great idea! I just put one coat on, but will be adding more later.
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About to reassemble here...
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You'll notice I left the locks in. I ended up taking out the jam door electronic lock, but that's it.
To explain, leaving the locks in prevents many possible problems with the motors stalling or jamming - which is something we don't want to do. Motors draw a significantly greater amount of current when starting up or stalling.
Looks like I took this picture before I replaced the wiring...I only brought one color of Teflon insulated wire with me, so I replaced the red and black wires with 18 gauge wire appropriately colored, which will be safer to run all that current through them.

I popped out the orange wall thingies in the battery drawer:
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and shaved off the blue divider, too:
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Notice the connector. Yep, that's a lithium polymer battery connection. That's how I'll be powering this thing! Way more current supply on tap, way more efficient.
Here it is charging:
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We are charging it so that both cells are the same voltage. Why? Because we are going to take it apart! this battery is an 8.2V cell. We need 4.2V.
So we're going to disconnect the cells, and put them in parallel for higher current supply.
This is the extremely dangerous part I referred to. We are charging them first so they are balanced, so we don't want any crazy voltage offset sparking when we do connect them. These discharge can a lot of current, so don't lick them or let them short circuit. YOU WILL DIE. srs bsns.
Here's a picture as we pull it apart:
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Connected in series, see?
We're going to connect the positive terminals together, and the negative terminals together. This will give us 4.2V.
Now, I said there was a safer way...They do make one cell LiPos. We just didn't have any, and we didn't feel like ordering them.
I won't go over the exact process because it's not safe for the average nerfer to try. So I didn't want people duplicating it.

Everything back together:
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Results?
We don't have actual measurements, but I would say around 80-90 feet.
Comparable to a overvolted Rayven, but here's the best part: at almost less than half the noise!

Hopefully get a video in this week, when we get our proper one cell LiPos in the mail....and our Tamiya Plasma Dashes! Even faster RPM woo!
I will also be installing Dynamat dampening material in it to see how much that helps.

So what did this accomplish?
Hopefully a different approach than just sticking Ultrafires in a blaster.
Put really nice motors in a blaster.
Quieter than overvolting.

EDIT: For people reading this, I no longer use this battery, because it's silly dangerous haha, and also I'm now using Mach Dash Pro motors, which have higher RPM and a more torque than Hyper Dashes. Less current draw than Plasma Dashes, which run far too hot to be useful in this purpose. They might work if you use lead free solder, I guess. The Mach Dashes are almost as fast, though.



#325701 Stryfe Modification - Something slightly different...

Posted by azrael on 24 January 2013 - 09:46 AM in Modifications

I think you guys being a bit ridiculous, I'm never turning on the motors when the gun is open. Why would I? And I initially understood "come apart" to meant come off the motor, that's why I responded like I did. In any case, I'm pretty sure there will be no issue.

Right now at 19000 RPM, they're fine, not in any danger of exploding like that. Shouldn't be a problem at 25000, the same motors have been used to spin plastic propellers just fine. the diameter is also much smaller than a CD, and the edges of the flywheel are stronger since there's an outer lip.

That CD exploded because it's not meant to be run faster than 10000 RPM or something like, whatever 52x read speed is. Plus it's using what, a vacuum motor? It's gonna vibrate like hell, because it's not meant to be spinning a disk like that.
You've brought up a ridiculous comparison, I think. :)



#325585 Stryfe Modification - Something slightly different...

Posted by azrael on 21 January 2013 - 10:11 PM in Modifications

I haven't noticed any dart wear, but I haven't done too much testing yet.

I got this mostly because I thought this would pair well with my 35 dart drums. So I've fired them off a couple of times through.



I'll get current readings tomorrow maybe, tonight I'm getting silly drunk.



#327292 Stryfe Modification - Something slightly different...

Posted by azrael on 24 February 2013 - 09:05 PM in Modifications

I put some Mach Dash Pros in my Stryfe. I like these a lot better. Only 3 bucks, too!
Almost no heat generated in the bushings. I can't feel any, TBH.
Current draw is a bit greater, haven't measured yet.
Range is at least 10 feet greater than before.

Mach Dash Pros are double axle motors, so you'll have to cut one side down. The RPM is higher, and I'd like to think torque is higher since it was designed to be a double axle motor haha.



#325956 Stryfe Modification - Something slightly different...

Posted by azrael on 28 January 2013 - 01:49 AM in Modifications

well, I've used BJTs (specifically in a Darlington configuration) before switching, they're cheaper and pretty simple to set up. Technically faster at switching usually, because of the FET gate capacitance.
I've had better experience with current handling too. Something with the capacitance in the MOSFET gate...

Either one could be used.



#326293 Stryfe Modification - Something slightly different...

Posted by azrael on 03 February 2013 - 11:56 PM in Modifications

Here's a quick test I took. Just mostly to show the recovery time.

http://youtu.be/HQnS0wkgEA4

Range is actually closer to 60-70 feet, using elites and modified streamlines (chopped stem and covered hole on the tip).

Here's a pic of the spread.
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unrelated, also I put a shotgun grip on my Recon ;D
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#326233 Stryfe Modification - Something slightly different...

Posted by azrael on 01 February 2013 - 04:31 PM in Modifications

I don't have the battery on me, and I only tested the stock setup for a few seconds before modding so I don't have a good frame of reference.

I definitely just don't describe my Stryfe as "bogged down" in the very least.



#326219 Stryfe Modification - Something slightly different...

Posted by azrael on 01 February 2013 - 11:53 AM in Modifications

well, there is something you are doing differently.
my Stryfe is very consistent, recovery time didn't seem any different than stock.

I'll record something tomorrow.



#326196 Stryfe Modification - Something slightly different...

Posted by azrael on 31 January 2013 - 05:21 PM in Modifications

I just got finished installing the Hyper Dash motors into my Stryfe. I must say, I like the stock motors more. The RPM is significantly higher on a much lower voltage with the Hyper Dash motors, but they seem to lack torque to a point where it's annoying. Waiting in between shots for a second or two is just not worth the slightly higher range they were allowing. The motors seemed to nearly die every time a dart traveled through the fly wheels.

Although, temporarily running these motors on a higher voltage was pretty crazy. I thought my shell was going to fly apart during some of my tests.

What battery are you running it off of? You can't just run them off Trustfires. The Tamiyas have a large stall current draw, and a fairly large constant current draw - Trustfires can't supply enough current, that was the whole point of my mod haha. I'm only running it at 4.2V, off a Li-Po that can deliver 25A of continuous current, and even more in bursts. Also, they're supposed to be run off a max of 4.5V.

I experience no wait in between shots. I'll try to take a video this weekend.



#325926 Stryfe Modification - Something slightly different...

Posted by azrael on 27 January 2013 - 07:00 PM in Modifications

Good idea on the dynamat. I like that idea.

I was thinking the same thing about those switches the other day. What's a BJT? You could use a relay and there's probably one that will handle the current and fit in the gun easy enough. Looks like I'm gonna have to hit the local electronics geek-shop tomorrow for one. My AtomicMods motors are coming tomorrow and they too draw a lot of current. My hope is that the Eneloop AAs will deliver the current so I don't have to resort to exotic batteries. I've heard of Eneloops delivering 4A without too much voltage drop. Guess I'm gonna find out.

After that I guess I'm gonna have to see about redesigning these darts because I'll be satisfied that at 40krpm and 50g-cm of torque (both motors combined) I've come as far as is reasonable and a little beyond with modifying the gun. The darts still leave much to be desired.

a BJT is a transistor. A relay can work too, that's a pretty good idea.



#325919 Stryfe Modification - Something slightly different...

Posted by azrael on 27 January 2013 - 05:35 PM in Modifications

Quick update.
We tried the Plasma Dashes, and got some Dynamat.

The Plasma Dashes draw too much current, and since our batteries can actually supply the current they need, the momentary switches in the acceleration trigger switch fry. I would guess they are only rated for 2A of continuous current, which is what the current draw of the Hyper Dash 2s just clocks under. According to my multimeter, they have a continuous current draw of 1.8A.

Plasma Dashes easily draw twice that, and their stall current is even greater than that.

Hah, totally forgot about checking the current rating for the switches. So that's the limiting factor.
The system can totally work, if you want to do a work around. You can either get higher rated switches, which are usually significantly bigger or the other idea we had. We were thinking about using the stock switches to actuate a BJT to do the switching. However, the BJT will still be dissipating a good amount of heat, so it will need to properly rated and heatsinked as well.
All in all, the Plasma Dashes run really hot, to the point where continuous fire is not too sustainable.

I ended up putting back in the Hyper Dash 2s, and infamous used some Torque Tuned Tamiyas we had lying around. The Torque tuned feature 14g per cm, compared to the Hyper Dash 2's 10g per cm, but have a lower RPM.

We are considering getting Mach Dashes, which have 20g per cm, and still have a high RPM. These have almost half the current draw of the Plasma Dashes, but a bit more than the Hyper Dash 2s.

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I installed a voltmeter, which is hooked up the acceleration trigger, so I know how much of the battery is drained.
You can see the Dynamat lining. It does work, and it does help. My gun is quieter than before, all vibration has stopped. There is still noise of course, but it's only from the motors. Pretty cool.
I also redid all my wiring with teflon insulated wire.

It's worth noting that while the Dynamat helps in the Rayven infamous owns, since the flywheel enclosure isn't bolted, there's a lot more rattling than in a Stryfe.



#325732 Stryfe Modification - Something slightly different...

Posted by azrael on 24 January 2013 - 06:54 PM in Modifications

Its low risk, sure. But at 40,000-60,000+ RPM that some of these racing motors spin at its definitely possible for someone to have an anomalous weak flywheel disintegrate at speed. Low risk but high penalty. It only takes a pair of safety glases to protect your eyes if you're bench-testing.

The Tamiya Dash series of motors run $15-$20 shipped. There's a very good $5 alternative that I'm going to post about in a few days. I'm also going to test some $40ea AtomicMods motors just for giggles. I'm currently trying to decide whether torque or speed is more important for our application. If it is speed then the Plasma Dash motor is probably as good as its going to get, but I'm leaning towards torque being more important and these boutique slot-car motor manufacturers don't publish very good performance data so its a little tricky selecting the right motor.

After a while crocodile.

The Plasma Dash is rated for 25000 RPM, 29k without a load. Nothing insaaaaane, IMO.
EDIT: Just looked up the AtomicMods you mentioned, definitely take care with those!

What's a good amount of torque, in your opinion?

The Hyper Dash 2s in mine now have no trouble gripping and flinging darts, I believe they have 10 grams per cm.
The Plasma Dash has 20 grams per cm.

The Plasma Dash is probably the priciest one, it's not hard to get it for less than 11 dollars each if you look. I just used Google. Shipping was like 5 bucks altogether for 4 motors.



#325976 Stryfe Modification - Something slightly different...

Posted by azrael on 28 January 2013 - 01:56 PM in Modifications

Would something like this work?

I understand that brushless motors are more efficient than standard ones, but what advantages would they have in a flywheel gun? More torque, therefore less downspin from firing?

Edit: I now realize that these are only 10k rpm, half the speed of the mod here. So I guess they wouldn't work? Or could torque make up for it? I really don't know much about flywheel guns.

Actually, because the 25k RPM spec is taken at 2.4V, my motors should be running at around 40k RPM since I use 4.2V.



#325770 Stryfe Modification - Something slightly different...

Posted by azrael on 25 January 2013 - 03:18 AM in Modifications

I don't think its possible to get enough torque out of a 130 size motor to keep the flywheel speed up while firing a dart. The best we can do is reduce the problem. If you listen carefully you can hear it even on my "high-torque" robotics motors. The moment the dart head contacts the flywheels the RPMs take a massive dump and have to spin back up after. It happens fast, and definitely faster then with the OE motors but its still audible.

Also, do the math. The flywheels are approximately 4" in circumference. Multiply (RPMs X 4")/12" and you get your theoretical dart speed. My darts shoot≈90ft ptg and leave the gun going 100fps (measured with a balistics chronograph.) That calculates to 300rpm. My motors are 25,000rpm. The problem is obvious. That tells me I don't even need 1000rpm free-running speed if I can get a motor strong enough to pass a dart without losing more then 50% of its speed. The only thing these high RPMs are doing is storing inertial energy in the flywheels, which does help but not enough. I suppose there's an argument to be made for adding mass to the flywheels as long as the post-shot re-spin-up isn't too slow.

Someone please be my hero and convert their blaster to larger diameter brushless motors. It would require major reconstructive surgery on the blaster but the results would be in a whole 'nother universe.

After a while crocigator

surely you don't need much torque to toss a dart that only weighs 50 grams?

Can you explain your math? I'm not following where you derived that from... It definitely seems like an oversimplified model to follow.

One thing that your analysis doesn't explain is that dart speed remains pretty constant with rapid fire shots for me. If it was losing that much energy I would think it be apparent after a shot. I'm pretty sure these motors have plenty of torque for our purposes.



#325716 Stryfe Modification - Something slightly different...

Posted by azrael on 24 January 2013 - 04:26 PM in Modifications

The Hyper Dash 2s were something he had lying around, so I'm not sure.
The Plasma Dashes I ordered were 10.50 each.



#329094 RoughCut 4x4 "Dudley"

Posted by azrael on 27 April 2013 - 02:32 PM in Modifications

Nice!

Any chance of a firing video?