General Mech verses Elect question.

Firstly I will say that I have done some searching and not found a similar question, however I'm still not 100% convinced that it hasn't been asked before so if I'm wrong I apologise and hope that someone can flame me with the appropriate link.

I'm wondering for all you hard core Nerf nuts out there whether there is a definite preference to Mechanical blasters over Electro-Mechanical blasters?

I know the mechanical ones have less things to go wrong during use, but have the Electronic ones proven that they are less reliable or is it just a perceived threat? Are the benefits of the full auto outweighed by the potential problems?

I've moved this to the questions thread.

Umm. Well did you mean flywheel electronic? Because the stampede is an electronic.

I do feel slightly partial towards mechanical blasters, though I do have a few electric blasters. I've had problems with my modded stampede but my vulcan is still going strong.

In my experience I have found electric blasters harder to mod internally, but they are easy to amp up the voltage in. Springers are for the most part easy to mod internally, but have a lower rate of fire. As for reliability, I haven't had issues with either, although if you mod to hell out of them, a springer doesn't have gears to worry about stripping, and have less moving parts, so theoretically they should be more reliable. But it's really up to you.

It will come as no surprise to regular punters here that I am a HUGE fan of the Stampede.

When warring with my sons and their mates, it is all I need.

To build a reliable one is an intermediate to advanced mod, but well worth the effort.

It comes naturally for me now to fire single shot semi auto, three shot bursts and full auto without any heavy concentration on the trigger.

IMHO, for $50 it's a kicker.

littlebro05 wrote:Umm. Well did you mean flywheel electronic? Because the stampede is an electronic.

I meant Electro-mechanical... Though I suspect we are talking about the same thing. IMHO, I have not seen a Nerf blaster that my 20+ years as a fully qualified Electronics Technician would have me call Electronic, though saying that, it does bring up the main reason for my question.

The Stampede uses a switch and a motor, and the rest of the firing sequence is fully mechanical other than the safety cut-out switches. Motors and switches are generally classed as Electric components rather than Electronic... Though maybe I'm just being a major pedant. I was considering adding some "smarts" to my Stampede as a mod, and removing some of the mechanical reliance which tends to have a limiting factor.

Spending some time studying the firing sequence of the Stampede I noticed that the mechanical linkages would by design start causing issue when the voltage is increased as there is the potential for the gear train to pick-up and start moving the breech/plunger shell before it has managed to get completely to the locking mech. In a stock Stampede this is carefully balanced with the return spring, however once the voltage increases then there could be reliability problems. Also the timing of the dart being raise to the correct position is a variable.

What I'm considering would be a substantial change in the way the the sequence is managed. Instead of carefully designed mechanical interactions controlling the firing sequence I'm contemplating using a microprocessor to monitor and control the sequence from the trigger press through to firing the dart and the plunger returning to rest. All that will really take place is that the micro could control the on time of the motor, ensuring that once the dart if fired the motor rests until the plunger has fully returned As at the moment it continues to run which would lead to timings of mechanical actions getting out of sequence.

In practice this means that you could do things such as disabling the stock on/off switch and using it as a single shot / 3 dart burst switch instead. You could even have the microprocessor monitor your clip and as long as you load the same number each time it could tell you when you only have 2 or 3 shots left. It would also allow for data to be retained such as ROF figures recorded, battery monitoring and even variable/programmable ROF for those times you don't need to go all out.

Anyway... At the moment that is purely an idea, and one that I am intrigued as to whether it would be desirable, or whether it would be more of a gimmick. After all, I was introduced to Nerf by the geek community, and it would be so nice to have the ultimate in Nerf Geekery.

Syridian wrote:

littlebro05 wrote:Umm. Well did you mean flywheel electronic? Because the stampede is an electronic.

I meant Electro-mechanical... Though I suspect we are talking about the same thing. IMHO, I have not seen a Nerf blaster that my 20+ years as a fully qualified Electronics Technician would have me call Electronic, though saying that, it does bring up the main reason for my question.

The Stampede uses a switch and a motor, and the rest of the firing sequence is fully mechanical other than the safety cut-out switches. Motors and switches are generally classed as Electric components rather than Electronic... Though maybe I'm just being a major pedant. I was considering adding some "smarts" to my Stampede as a mod, and removing some of the mechanical reliance which tends to have a limiting factor.

Spending some time studying the firing sequence of the Stampede I noticed that the mechanical linkages would by design start causing issue when the voltage is increased as there is the potential for the gear train to pick-up and start moving the breech/plunger shell before it has managed to get completely to the locking mech. In a stock Stampede this is carefully balanced with the return spring, however once the voltage increases then there could be reliability problems. Also the timing of the dart being raise to the correct position is a variable.

What I'm considering would be a substantial change in the way the the sequence is managed. Instead of carefully designed mechanical interactions controlling the firing sequence I'm contemplating using a microprocessor to monitor and control the sequence from the trigger press through to firing the dart and the plunger returning to rest. All that will really take place is that the micro could control the on time of the motor, ensuring that once the dart if fired the motor rests until the plunger has fully returned As at the moment it continues to run which would lead to timings of mechanical actions getting out of sequence.

In practice this means that you could do things such as disabling the stock on/off switch and using it as a single shot / 3 dart burst switch instead. You could even have the microprocessor monitor your clip and as long as you load the same number each time it could tell you when you only have 2 or 3 shots left. It would also allow for data to be retained such as ROF figures recorded, battery monitoring and even variable/programmable ROF for those times you don't need to go all out.

Anyway... At the moment that is purely an idea, and one that I am intrigued as to whether it would be desirable, or whether it would be more of a gimmick. After all, I was introduced to Nerf by the geek community, and it would be so nice to have the ultimate in Nerf Geekery.

That sounds great! I would buy one if you made some working models in a kit. Also, does this mean you could add an ammo counter on a 2 digit LED display? What sort of microprocessor would you use? PIC? AMTEL?

Sorry dude. I can't comprehend this information. My head hurts reading it :(. I'll let the more experienced electrical members of forums discuss this.

I'll just nod and smile on this one, way over my head. though, I love reading up on how these sort of epic geekery projects come together!

Ummmm... yeh... pretty technical stuff.

I'll take my mechanical LongShot or clip-fed Titan any day...

Will be interesting to see WIP though.

Cheers,

Nice, good to have someone with some real electrical knowledge around here. I have a fairly limited knowledge or electronics, mostly learned through playing whit stuff myself and living with an engineering student when we started Nerfing.

Dart pop up timing from a stock clip starts becoming an issue around 30v. The rate of fire is just too high for the clip to load darts fast enough. However it's all a bit academic at that point unless you've upgraded the motor as you'll be burning through them very quickly.

A microprocessor to monitor and control the sequence certainly sounds doable and probably not all that difficult. I'd imagine that the hard part would be to figure out the correct timing. Once you've got that down, using a switch to limit it to a semi auto mode should be fairly straight forward.

Battery monitoring would be quite nice and isn't something I'd considered before. Will have to make one shortly... Plenty of people have done ammo counters before. Personally I think they're well cool but not really worth the effort from a purely practical standing.

All in all though, very keen to see how this progresses. Keep us posted please

Yeh, once again, it's nice to have a different perspective on things.

Though, I have to interject... we have a number of guys here with quality electrical knowledge, including 238232 and ONN and a few other guys

Cheers,

Sorry, re read my first sentence and that didn't really come out as intended. Lets rephrase that to be "it's good to have more people around here with real electrical knowledge".

Jeo wrote:Sorry, re read my first sentence and that didn't really come out as intended. Lets rephrase that to be "it's good to have more people around here with real electrical knowledge".

haha... wasn't having a dig at you mate, not at all.

Just wanted to highlight the couple of member's who have been a big help for me with my severe lack of electrical knowledge. But hey, I can at least make nice Lshot's and pretty handy paint jobs. Can't be good at everything!! lol

Cheers,

clunk07 wrote:Yeh, once again, it's nice to have a different perspective on things.

Though, I have to interject... we have a number of guys here with quality electrical knowledge, including 238232 and ONN and a few other guys

Cheers,

Why thank you Clunk!

And how've you been anyway?

While I do understand what he's getting at, and while I don't doubt that it can be done/he can do it, it's going to be a complicated one off (or limited run) item.

Sure the different firing mode selector is doable and will be a great feature, but the limiting factor in the Stampede is the dart feeding at speed.

Gears and mechanisms are great in that model, you just need to reassemble the thing correctly and use a lighter lube for higher speeds.

Back on topic...

It's the pick of the "electric" models, and if you're looking to make it "electronic" and have the resources, it's certainly possible.

I'm going to focus on what it really needs... a smooth feeding, sealed breach so as to take advantage of the full potential of it's fantastic direct plunger design.

clunk07 wrote:haha... wasn't having a dig at you mate, not at all.

All good. Point still stands though.

oznerfnerd wrote:I'm going to focus on what it really needs... a smooth feeding, sealed breach so as to take advantage of the full potential of it's fantastic direct plunger design.

Now that's something people would be interested in!

Hey ONN,

Any time mate - credit where credit is due etc.

Yeh, things are looking up. Did a quick mod to an SM3K this week - 120 ft flat x 8 auto-rotating barrels, in less than half an hour. Not exactly a LS or a Stampede, but I may actually be back in business... once I organise some workspace!!

Cheers,

Jeo wrote:Dart pop up timing from a stock clip starts becoming an issue around 30v. The rate of fire is just too high for the clip to load darts fast enough. However it's all a bit academic at that point unless you've upgraded the motor as you'll be burning through them very quickly.

LOL, Yes, I figure you would be. Have there been many experimentations at those higher voltages? Personally I would much prefer to put the time in improving the drive system rather than using the hammer approach and just over supplying a $0.50 motor. But thin I guess it really depends on how extreme and how much money you want to throw at a project. The way I see it is that I'm in it for the experience of doing the mod, not necessarily the outcome.

Jeo also wrote:I'd imagine that the hard part would be to figure out the correct timing.

Actually by using the smarts of a Microprocessor we can do things like monitor the motor current so that the micro knows when it's no longer driving the plunger spring. So timing would be purely relative. Instead of having the mechanical linkage to ensure the full firing sequence by holding the trigger on whilst the motor runs through a cycle the micro will detect the trigger and turn the motor on then wait for the current to drop back to a non-loaded value to shut off the motor.

And Jeo also wrote:Battery monitoring would be quite nice and isn't something I'd considered before. Will have to make one shortly... Plenty of people have done ammo counters before. Personally I think they're well cool but not really worth the effort from a purely practical standing.

There are heaps of other things that can be done just with a bit of software and minimal electronics. Such as the ability to add a PIR sensor to the front and have the gun auto fire when someone step in front of it (Great for one man ambushes, set the gun up behind a barricade and switch it to auto, then sneak around the side with a Recon and have some fun), or even remote firing with a small keyring remote, adding LED sequences for muzzle flash, Bluetooth data monitoring to a smartphone to monitor the blaster performance, with some sensors in the barrel you could monitor muzzel velocity, and track how consistent it is. I could go on, but I think at the moment I'm just thinking up extravagances that only someone like myself would actually find useful.

oznerfnerd wrote:I'm going to focus on what it really needs... a smooth feeding, sealed breach so as to take advantage of the full potential of it's fantastic direct plunger design.

Now here's where I show my ignorance, I'm confused I thought the breach was actually quite a good seal? Are you talking about sealing the breach to the rest of the barrel? If you are then I would be interested in finding out how much of a performance increase you get out of that considering that with the tapered insides of the plunger casing you only seem to get a seal in the last third or so of the plunger movement. Even with fixing the plunger seal you may only get half of the air compressed in the plunger tube (though I have been considering finding out of you can get some brass tubing that fits neatly within the plunger tube without reducing it's capacity too much. given the current amount of air volume that I can detect I wouldn't have thought that sealing the breach to the barrel would have increased it's performance by much. Not to mention that the faux barrel is oversized and you certainly wouldn't get a seal around the dart unless you replaced the barrel as well. Not that I'm trying to poke holes!!! I'm just trying to understand this more clearly as it seems like an interesting problem. Is there a thread on this topic that I haven't been able to find?

OzNerfNerd, you have mentioned in other posts about the Stampede that "Set up properly, the Stampede is an awesome blaster."... Is there a ONN Stampede set-up guide around somewhere that I could use to set mine up?

The Stampede's breech is rather poor. I've heard of a few member's trialling brass/petg/conduit breeches in various shapes and forms. Though, nothing definitive has been showcased yet.
Currently, I think ranges of around 75 feet or so, slightly angled, are pretty much normal for a fully modded Stampede.

As for a guide - try littlebro's:

http://www.oznerf.com/t3506-write-up-nerf-stampede-ecs-general-modifications#62541

Stampede is pretty simple to mod, so there shouldn't be too many issues. My commission's utilise either a 9, 10 or 13kg spring upgrade. I have heard of people utilising the stock spring as well, but it's not something that I find a need for. I've commissioned 14 Stampede's in the last 9 months, and most people want a mid-range blaster, with high ROF. Using 4 x 14500 unprotected li-ion batt's, I tend to get around 4.5 to 5 rounds per second. Doesn't take much time to empty a Raider drum if you go crazy.

Of course, this opens up the never-ending debate on Power supply options, which, hopefully, won't become an issue in this thread (seriously guys - let's not make a debate, unless you're looking for a holiday... and, yes, I'm back... haha)

The 3 most common options are:

4 x 14500 unprotected li-ion's
Li-po packs (I have not a great deal of experience, but I think most people run 2 x 7.2v packs)
12v SLA batteries

Cheers,

Syridian wrote:

Jeo wrote:Dart pop up timing from a stock clip starts becoming an issue around 30v. The rate of fire is just too high for the clip to load darts fast enough. However it's all a bit academic at that point unless you've upgraded the motor as you'll be burning through them very quickly.

LOL, Yes, I figure you would be. Have there been many experimentations at those higher voltages? Personally I would much prefer to put the time in improving the drive system rather than using the hammer approach and just over supplying a $0.50 motor. But thin I guess it really depends on how extreme and how much money you want to throw at a project. The way I see it is that I'm in it for the experience of doing the mod, not necessarily the outcome.

Jeo also wrote:I'd imagine that the hard part would be to figure out the correct timing.

Actually by using the smarts of a Microprocessor we can do things like monitor the motor current so that the micro knows when it's no longer driving the plunger spring. So timing would be purely relative. Instead of having the mechanical linkage to ensure the full firing sequence by holding the trigger on whilst the motor runs through a cycle the micro will detect the trigger and turn the motor on then wait for the current to drop back to a non-loaded value to shut off the motor.

And Jeo also wrote:Battery monitoring would be quite nice and isn't something I'd considered before. Will have to make one shortly... Plenty of people have done ammo counters before. Personally I think they're well cool but not really worth the effort from a purely practical standing.

There are heaps of other things that can be done just with a bit of software and minimal electronics. Such as the ability to add a PIR sensor to the front and have the gun auto fire when someone step in front of it (Great for one man ambushes, set the gun up behind a barricade and switch it to auto, then sneak around the side with a Recon and have some fun), or even remote firing with a small keyring remote, adding LED sequences for muzzle flash, Bluetooth data monitoring to a smartphone to monitor the blaster performance, with some sensors in the barrel you could monitor muzzel velocity, and track how consistent it is. I could go on, but I think at the moment I'm just thinking up extravagances that only someone like myself would actually find useful.

oznerfnerd wrote:I'm going to focus on what it really needs... a smooth feeding, sealed breach so as to take advantage of the full potential of it's fantastic direct plunger design.

Now here's where I show my ignorance, I'm confused I thought the breach was actually quite a good seal? Are you talking about sealing the breach to the rest of the barrel? If you are then I would be interested in finding out how much of a performance increase you get out of that considering that with the tapered insides of the plunger casing you only seem to get a seal in the last third or so of the plunger movement. Even with fixing the plunger seal you may only get half of the air compressed in the plunger tube (though I have been considering finding out of you can get some brass tubing that fits neatly within the plunger tube without reducing it's capacity too much. given the current amount of air volume that I can detect I wouldn't have thought that sealing the breach to the barrel would have increased it's performance by much. Not to mention that the faux barrel is oversized and you certainly wouldn't get a seal around the dart unless you replaced the barrel as well. Not that I'm trying to poke holes!!! I'm just trying to understand this more clearly as it seems like an interesting problem. Is there a thread on this topic that I haven't been able to find?

OzNerfNerd, you have mentioned in other posts about the Stampede that "Set up properly, the Stampede is an awesome blaster."... Is there a ONN Stampede set-up guide around somewhere that I could use to set mine up?

Far out mate,

You do love typing.

I'm just home from work and tired, so I'll keep it short and sweet.

Yes, as Clunk said, the Stampede breach has some issues when you try to amp it up.

There are some feeding/jamming issues that occur at higher ROF's, and while the power is improved with a heavier spring, many believe that a plunger this size could deliver much more power if the breach could be sealed better.

There is also the elusive "onfiring" problem that can occur with higher voltage/ROF's.

I do a few short mod guides specific to some of my products, but haven't done one for the Stampede.

I'll get howled at for this, but I believe that some of the best pictorial mod guides can be found on SGNerf's modworks site.

Check it out.

Nah ONN,

Definitely no issue with referencing SgNerf's guides. I'm sure most of the seasoned modder's in Australia can credit a fair bit of their work to guides from either psyk or SgNerf.

Cheers,

Thanks Oznerfnerd and Clunk.

It's been most helpful. Yes, I can credit SgNerf with all of the mods I have done so far including the case mods and custom paint job (other mods were AR removal, impact dampener and voltage increase).

Yes, I do like to type... Or should I say that I do like to discuss issues in detail so as to get all of the information I can and a full understanding of how to implement it. I also like to share my knowledge and discuss it so as to merge multiple streams of knowledge into one more comprehensive version.

These forums have helped me to understand the plunger/teflon tape mod better which in other tutorials didn't seem that straight forward. I now have my stampede vacuum loading darts.

This brings me back to the previous questions.

Where exactly do you want to seal the breach?

Are you talking about a better seal in the breach itself, between the breach and the dart?

Or are you talking about a better seal between the breach and the barrel?

Sorry for bolding, I just figured as I am notorious for typing long-winded boring posts I would highlight the important bits. Gotta love forums.

Both scenario's would be the goal.

A more snug fit for the dart in the barrel, and an air-tight seal between the breech and barrel.

Cheers,

Haha at least you 'dn't tlk lyk dis'.

You don't want the plunger seal too tight. This is because even if there isn't any air escaping, if the plunger is moving too slowly, that means the air pushing out of the plunger is slowed down. Thus, decreasing in range and velocity. You want it to be at around 90-95% plunger seal. That way, it moves quick enough to push the dart out faster, but air loss is so minimal that it becomes unnoticable.

You can experiment that with the teflon tape to get the fastest moving plunger as well a nice seal.

With regards to 18drt mags not feeding fast enough for higher-than-reliable voltages, why not a bigger magazine spring? Fair enough we're dealing with foam, not brass and jacketed lead so there will be a reliability limit where the feed spring squashes the darts out of shape.

Might even be able to just stack two springs. Unfortunately I just fed the last of my 9v procells to a guitar pedal so crazy DC voltages are out of my league.

mister_elliott wrote:With regards to 18drt mags not feeding fast enough for higher-than-reliable voltages, why not a bigger magazine spring? Fair enough we're dealing with foam, not brass and jacketed lead so there will be a reliability limit where the feed spring squashes the darts out of shape.

Might even be able to just stack two springs. Unfortunately I just fed the last of my 9v procells to a guitar pedal so crazy DC voltages are out of my league.

I've often considered that, but some darts jump out of the clip by themselves even with the standard spring.

You might need to extend or heat mold the "lips" of the clip, to narrow the gap a bit.

And then you'd have to make sure you didn't close it too much for it to snap into the breach.

Not trying to step on any toes or tell people there wrong here, but just provide another opinion.

The seal between the dart and the breach in my stampede is good enough to vacuum load darts. And now that I have used teflon tape on the plunger I get a nice "POP" as the dart leaves the breach. I'm thinking that that's probably the best seal I'm going to need. They are after all only foam darts.

As for the seal between the breach and the barrel... Given that the barrel is considerably larger bore than the dart and the fact that the volume of the usable compressible space in the Plunger tube is no where near the volume needed to project a dart the full length of the barrel anyway, I doubt that that any increase of performance of the dart would be noticeable. This is based on the physics that in order to project the dart through a tube whilst increasing it's velocity during the entire length you need to have a substantial increase in localised pressure behind the dart. If you don't, it'll stop when the pressure is equalised with the atmospheric pressure, ie when the volume that was originally uncompressed reaches it's uncompressed state again.

Now in order to make this work you would probably need to have a substantially bigger volume of compressible space (space in the plunger tube once the plunger has started compressing air). In my stampede this is only about 2/3rds of the whole plunger assembly and calculating this volume out says to me that it's too big a project due to the fact that you would virtually need to rebuild the entire blaster.

If anything I would probably prefer to remove the barrel entirely as any benefits in accuracy that you might gain would be offset by the loss of momentum of the dart through the barrel. That is just the nature of of the physics involved. Though I must admit I do like the look of the stampede barrel.

Anyway, once I get my "μStampede" up and running I'll add code and circuitry to the barrel to sense muzzle velocity. Then we can really start putting some of these mods to the test. BTW, I'm really enjoying this discussion and hope that others are too. The ability to share idea's and discuss finding is what makes Forum communities fantastic ways of sharing research and idea's.

Syridian,

I'm assuming that you're using stock darts?

Correct me if I'm wrong.

Cheers,

Were are both NOT asses.

Yes... your assumptions are correct, though I do have some of the blue darts with the flat-ish rubber ends as well. I do actually prefer the stock darts, they seem to fire better.

I do have another question...

Has anyone actually tried Motor substitutions in the Stampede?

I keep looking at some of the alternatives thinking that instead of ramping up the voltage of a $0.50 crap 6V rated motor, why not replace the entire motor with a high efficiency RC motor that is designed to provide high torque and high speed?

Or even go with a brushless system that most of the Li-Po batteries that people are using are designed to power... Of course this would really require going "Electronic", but oh what fun could be had. A brushless motor with ECS could be a simpler solution to providing a dialable ROF, though combined with a μController would provide an awesome combination.

Totally overkill, but then what isn't with most custom mods.