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LordSparrow

Cheap Motor Questions

*Sighs*

Hello.
I want to do my first "proper" mod, like lipo and motor upgrades and everything, ready for November's GuN. I was thinking that I could do it on a reasonable budget, and that I would expeiriment with some things on the blaster, you know, make it really personal, something I could be proud of.
Well, after a lot of research, I found out that it was actually going to cost more than my initial budget. Fine, I thought, I'll just sell some of my blasters, I dont have room to store them and I never use them anyway (Post still up at: [url] http://britnerf.co.uk/about3312.html [/url] . So yeah. Time goes by, I sell about 3 blasters, still not enough for the hellcats or potential honey badgers that I wanted.
The fact that I bought 8 ultrafires plus charger doesnt help my money either. I was hoping they might be a substitute for a lipo. Further research shows that this is not true.



Then, I come across ebay links, a lot of them, advertising 130 and 180 sized motors at a similiar rating to the hellcats, rhinos and other motors, such as these, maybe?:

[url] http://www.ebay.com/itm/New-180-D...%3D6%26sd%3D231726371857#shpCntId [/url]

[url] http://www.ebay.com/itm/1pcs-3-7V...3D2%26rkt%3D6%26sd%3D121960252153 [/url]

[url] http://www.ebay.com/itm/New-130-D...3D2%26rkt%3D6%26sd%3D152240473009 [/url]

I understand that they are rated 6 volts, but would they be a reasonable alternative to MTB motors?
There is also the issue that they are being shipped from china, and they might not be able to ship in time.

If it wasn't an issue of cash, then I would love to buy them from Blaster Smiths like any sane nerfer.
Thanks in advance.[/url]
Dazzle740

I did something very similar to you, when i first started to mod blasters i searched and found what i thought to be acceptable alternative motors online. Ordered them and waited for them to arrive from China (which you will find will be a minimum of 2 weeks) did all the usual checks when fitting used normal AA batteries to check rotation etc. then when i connected a Lipo for the first real test upon depressing the trigger for the first time was met with an almighty high pitched (and VERY loud) banshee type scream and the motors shat themselves and immediately died lol.
I now will only buy MTB motors from either Blastersmiths or Oldnoob of this site.
LordSparrow

Dazzle740 wrote:
I now will only buy MTB motors from either Blastersmiths or Oldnoob of this site.

As mentioned above, I would LOVE to do that, but getting the cash for this sort of thing within 10 days, waiting for it, installing it and then testing it just seems impossible.
Dazzle740

I do know what you mean as I have had two blasters under going mods for nearly two months now. Was hoping to have them done for last months GuN but cosmetic mod didn't go to plan, first time hydro dipping lol.
And I'm rapidly running out of time to have them complete for this month's GuN but taking your time and doing it properly is ultimately the best way.
Personally I would wait save up and get decent MTB motors and pay out once and know they will work.
At each Gun event loads of the players use standard blasters, I myself use a standard hammershot for some of the HvZ games.
SSGT

Re: Cheap Motor Questions

I think you might have fallen into the same trap that quite a few newcomers (and probably most of us at some point) fall into. You're (understandably) enthusiastic about completing your first modification and want to rush out and buy things but you'll inevitably find that you've wasted your money and end up needing to spend more than you would initially to get where you wanted to be in the first place.

As Dazzle pointed you're unlikely to get motors shipped from China within two weeks and almost certainly won't get them in time to install before the next GuN. To be honest, even if you bought MTB motors from BSUK, I don't think you'd do yourself a favour having the next GuN as your deadline. If this is your first proper electrical mod you'll want to take the time to make sure it's done well. Quite honestly you're better off waiting and saving up and doing a good job than trying to rush it. There may also be other things that you haven't considered, for instance two of the motors you linked were 180 size and the other was a 130 size motor - which size are you after? 130s fit inside the existing shell with minimal modification but tend to have less torque than 180s and so have comparatively slower rev and response times (which you prioritise will largely depend on what you want out of your finished build). If you do go for 180s then you need to think about how you're going to cover the holes you need to cut in the shell for them to fit - are you going to buy a pre-existing motor cover, like those that BSUK offers, or would you prefer to try and make one yourself? Then what are doing about the power supply? If you're using aftermarket motors you're pretty much ruling out drop-in 14500 size cells but, if you're using a LiPo, do you know the discharge rate or capacity you'll need? If so, will you need a battery tray expander to fit the pack you need? Again, if you do, would you be buying one or building one? What about switchgear and wiring? Is it rated to meet the current demands of the motors you've chosen? These are all important questions that you need to nail down before you buy anything otherwise you'll end up blowing your budget and/or wasting money on a load of components that end up going unused when you find that you wanted/needed something else instead.

To answer the question on the motors you linked, only the first (30800RPM on 2S) and the third (36200RPM on 3S) would likely be much use but that's assuming they even meet the (limited - there's no torque figures) specs listed. Even if they are approximately to spec you never know what the quality control is like - you may end up with two motors with wildly differing performance even though they are supposed to be the same motor and even if they are well matched they may not last more than a few games.
OldNoob

All of those motors represent a good way to waste further money. Not only are they largely untested and often rubbish bs ones that work, they also won't arrive in time for GuN
Learn from your mistakes, sell all your surplus and buy the parts for a proper primary for games.
If you have the base blaster, be clever. Rewire it, don't worry about the stock rev switch, retain the standard motors. Ask other GuN attendees if you can borrow 3 IMR cells to run it on. Go play a game.
Then you can go back and add things to it as you have more money, start with a lipo and charger plus a pair of motors.
Sell your trashfires to a flashlight person. You can use the charger for IMR cells if you want, or sell it with the batteries, just don't advertise it on here.
blindgeekuk

I might have 2 IMR's and 2 dummy's on hand for GuN11.

Like the others have said, don't try and rush it, especially not for this GuN. You've got a few months to try it over the winter, and get the right gear.

I'd actually recommend having 2 -  a kid friendly one, with a simple reqire on stock motors/cage thats using a 2s, and something fancy with rhino's and more interesting internals (mosfet, artifact cage, special flywheels) for the 13+ games
Dustybin

I was searching those links for torque, to no avail. At 1 amp draw with no load, I highly doubt that they will produce enough torque for Nerf flywheels.
OldNoob

Also, you don't have to do it all RIGHT NOW! It took me 6 months to complete my first proper primary.
Borrow 2 IMR's off BG and play, they will run in a stock stryfe loom fine. Air you get some wire and do a basic rewire before then that's a bonus.
LordSparrow

Re: Cheap Motor Questions

Thanks for your quick reply guys.
SSGT: I understand the size of motors varies, and I have seen info about modifying shells with 180's. I thought that I could create my own plate to cover the motors, maybe with something cheap from poundland and then dremeling it, and then epoxying it onto the shell. The blaster in question is a Hyperfire, so I will need at least 1 130 motor, for the belt drive, and two 130 or 180 motors for the flywheels.
As for the rewiring, I bought this beefy copper wire from maplin. Ive been practising rewiring some of my own blasters, so I should be OK with that part.
And then the lipo. Ive been googling, looking for equations, (For a few days, V = I / R was all i could think of  Shocked ). Ive cosidered microswitches, read about swapping the little weakiling they call a JST for a big boy deans, researched about chargers, looked at what C was and all sorts of other stuff. But hey, Ultrafires on sale? Only two four packs left? Primitive brain: Buy now, ask questions later.

OldNoob: I was warned of your hatred towards Ultrafires. I still dont understand whats so bad about them. I trust you guys though, you have experience in this field, but in my eyes, theyre still better than AAs, therefore better than anything Ive got. Ill keep them, just as a way to increase performance without going into the blaster, at least until I can scramble enough change to get proper IMRs. I will try to be gradual, as you suggested.

BGUK: Im not sure that 2 IMRs would be enough to power a hyperfire, but I cant thank you enough for your interest and quick reply. Im turning the hyperfire into a hyperpistol (more on that later), so Ill find a UK located AA battery tray off ebay and slip it into the fore grip deadspace.

Anyway, thanks again for your quick reply's and interest guys.
Lessons learned: Cheap Ebay motors are a no-go
                        Ultrafires and Trustfires are not to be trusted
                        Be gradual with mods on a budget
                        Spend more money for highr quality components that will work longer

And as BGUK pointed out:



Ill have more than enough time to test my setup then.
Minky

It's a marathon not a sprint for sure..  As you know I've started my first mod which I hope to be my primary ongoing and although I'm a week or so in I can impart these not so sage words of advice:
Ask even stupider questions Smile I got all excited about rebarreling the RC and ran out and bought 17/32 brass.. Of course I needed it to be that on the inside..
Be ready to adapt,  despite thinking I'd comprehensively thought everything out almost nothing is actually going perfectly to plan, but despite this,  step by step it's shaping up awesome.
Dremels really aren't as useful as you tubers make out and I'm so happy I listened to everyone about what saws to buy. Used the thing once.
Stock plasters. Literally just ran my finger over a scalpel like a damn idiot!

So maybe, not that helpful but I hope if you feel you've made some poor choices know you're not alone!  Smile
OldNoob

Don't change Hyperfire motors unless you are changing the flywheel cage, all that will happen is you will make whirlybirds. Rewire it and run a 2s lipo or 8.4v Nimh, that's all it's good for.

Few helpful terms.

Voltage- an electromotive force or potential difference expressed in volts.
More VOLTS=motors spin faster

Current- An electric current is a flow of electric charge. In electric circuits this charge is often carried by moving electrons in a wire. It can also be carried by ions in an electrolyte.

Motors draw more CURRENT as load on them INCREASES, up to their stall current, where they are stopped from rotating. If there's a failure or short, the circuit can draw the FULL current available from the battery. This happened in the recent flaming Vauxhall Zafira recall!

Basic Nerf 130 motors typically draw 4-5A EACH under stall load and about 2A when you start them, this is the BURST CURRENT. Mod motors can draw 30A burst.
A Tossfire can supply the VOLTAGE to make your motors spin fast with no load on. The minute a LOAD is applied, the motor draws more CURRENT from the BATTERY.
This is where the problem starts- Your Tossfire  can supply, on a good day, 2A. That is not even enough to meet the START UP current of ONE stock motor.
What happens then is a fat voltage sag, as the battery can't supply the energy required. What you are now doing is OVER DISCHARHING. This is when you are pushing the battery beyond its designed limit. Try lifting a grown adult over your head. You are the battery, the adult is the motor load.
A Tossfire is a LiCo cell, THE MOST VOLATILE lithium chemistry, with NO PROTECTIVE CIRCUIT, unlike the cells in your phone. Look what happened with the hew Galaxy phone battery, that's a LiCo failure, what happens when you over discharge a Lico cell and the protection circuit doesn't work or isn't there.
All that is without the risk of cloned, damaged or dangerous rewraps which are often sold as *fire cells.


I don't hate Ultrafires, I do hate people potentially burning down their house, injuring themselves, injuring others or giving our community negative publicity through bad practice.
SSGT

Re: Cheap Motor Questions

LordSparrow wrote:
I thought that I could create my own plate to cover the motors, maybe with something cheap from poundland and then dremeling it, and then epoxying it onto the shell.


Nothing wrong with that. People have done everthing from sheets of plastic paint/bottle caps and even vortex discs. Sometimes you just need to raise the existing motor cover.

LordSparrow wrote:
The blaster in question is a Hyperfire...


Echoing ON, the Hyperfire flyhweel cage doesn't take too well to upgrades that increase the flywheel speed, nor does the conveyor always feed too well at higher speeds. Also note that the conveyor motor is not a 130/180 size motor, it's the equivalent of an FA260 (metal brush flat-can 260). You can fit a 130 or 180 in there but it won't be a drop-in fit, you'll need to do some shimming or mounting with hardware/motor screws.

LordSparrow wrote:
As for the rewiring, I bought this beefy copper wire from maplin.


Do you have a link to that on the Maplin site? If it's solid core it's not really ideal for blaster wiring, stranded wire is much better.

All you really need to know regarding LiPo specs is that you want the product of the "burst" C rating and capacity to be greater than the maximum current the pack will ever need to deliver. If, for instance, you're three motors have a total stall current of 63A (i.e. two Hellcats and a Honey Badger all on 3S) then the pack discharge rate (C rating * capacity in Ah) should be equal to or greater than that (e.g. you could use a 3S 2200mAh pack with a 30C burst rating -> 2200mAh * 30C = 6600mA or 66A).

Microswitches are a little more complex (see this post) but, for the most part, you should aim for full-size 21A for the rev switch and sub-mini 10A for the trigger and cycle control (although others have used these for rev switches with no issues).

I'll echo ON again regarding *****fires (or any LiCo cell). They're low discharge and poor for motor applications. To be honest I wouldn't recommend buying into IMRs either if you know you'll move to packs in the future. Setup costs are about the same but if you do go with IMRs you'll end up spending that money again on packs anyway since even 14500 size IMRs struggle to power anything more powerful than a pair of stock 130 motors. Granted you probably have an Ultrafire charger already but, depending on the model/quality, it may not be the safest thing in the world - better off selling it and putting that money towards a pack charger IMO (which, with a cheap to make cell holder adapter, can charge IMRs and *****fires anyway).
Dazzle740

I am also (amongst other projects) modding a hyperfire, but I would personally do the same as I have and keep the stock belt motor and try to supply no more than approx 6.5 volts 7 at extreme . As beyond this or changing the motor for faster creates major headaches in reliable feeding of darts due to the belt speed being so high the teeth don't engage with each dart but instead just buzz over the top.  I have done this method and have just updated the flywheel end.
But either way the main thing is to not rush any aspect of your mod, as I said earlier my hyperfire will of taken just under two months to complete, not due to complexly of the mod but due to time available to sit and mod lol but just take your time and do things right the first time which might initially cost more for parts but ultimately will be cheaper due to not wasting money on tat.
tbr

blindgeekuk wrote:
I'd actually recommend having 2 -  a kid friendly one, with a simple reqire on stock motors/cage thats using a 2s, and something fancy with rhino's and more interesting internals (mosfet, artifact cage, special flywheels) for the 13+ games


That's exactly what I do, I currently use Stryfe's with a simple re-wire and a couple of IMR's for the Kid friendly games. And then bring out the Rhino and Hellcat powered Stryfe's for the 13+'s.
Broz

I've not seen anything appropriate wire wise at Maplin myself. I've asked in store if they sell stranded silicone wire and been met with either responses to the negative or blank expressions.
Franksie

Easily found cheaply on eBay and delivered within 2 days
LordSparrow

SSGT, actually, I had bought the wiring maybe 3-4 years back. It is solid core copper wire. Why is this bad?
As for the lipo, would this one work?
https://www.hobbyking.com/en_us/turnigy-2200mah-3s-30c-lipo-pack.html
To my understanding, it should, when not taking into account energy lost through heat + sound, power the three motors non-stop for 1 hour, right?

Honestly, in this situation time is the one thing Ive got plenty of. I can sit down and work on it for about  5-7 hours a day, maybe even full days on the weekend. Im the type of person who really get into the things I do.

ON, as for the flywheel cage, Could I just get a stryfe cage and stick it in with epoxy putty? I understand that I would have to make sure its in line with the barrell, so the darts dont spew out in a different direction.
I mean, its probably the same process as installing afterburners or more flywheels along the barrell.

Dazzle, did you use stick mags for your testing? Drac pointed out that drums have a less responsive spring than stick mags in his Hyperfire vs FDS Rapidstrike video.

Originally I was going to use the Solarbotics RM2s, running off 2 IMRs or 6-8 AAs. I wasnt so sure though. Many said that they are good motors compared to how little they cost, but I read that their brushes will burn out instantly if you give them too much voltage.

Minky - I find my dremel very useful, actually.
OldNoob

The stryfe cage doesn't fit. It won't stay gobbed in with putty or crap, you would have to set up new mountings in the right place and STRAIGHT as well as aligned to the pusher and barrel. Anyone mounting afterburners with gobs of putty is equally not a modder to emulate.
That lipo is 3s, everyone told you you will break the conveyor and get whirlybirds if you use 3.
Solid core wire IS NO GOOD, it won't bend through the shell and doesn't have the current carrying capacity of a comparable multistrand like this one save yourself hassle and buy the right bloody wire.
RM2's are flat out the worst POS motor ever. I know, I bought some.
SSGT

The main benefit of stranded core wire is the flexibility (especially if you get silicone or PTFE/Teflon insulated wire) - it's much easier to route through tight spaces. Solid core, especially thicker gauges, is more prone to kinking which can reduce the cross sectional area (effectively meaning you're using a thinner gauge wire at that point) but also weakens the wire at that point. Solid core is already less tolerant of vibration and, if there's a weak point at a kink, it's even more likely to fail and break due to fatigue.

3S 2200mAh pack with a 40C peak/burst discharge - it can supply up to 88A for up to 10 seconds so easily enough to power three of pretty much any motor you want (except maybe MTB Wolverines). It's hard to estimate how long exactly the pack will be able to power three motors for since it'll depend on the motors and the load applied to them for that time period (heat and sound, at least from the motors, largely don't matter since that's taken into account by the voltage/current spec - we know how much power goes in and that's all we need, we don't really care if it's going to mechanical power, sound or heat when calculating run time) but if you had 3 Hellcats running continuously that pack should be able to run them for 14 mins at their rated load or 1hr 36mins at no-load. There is a common (although very rough) rule of thumb that suggests that you go through about 1 mAh in capacity per dart fired but that will vary, among other things, based on the motors you use and how long during a game you tend to keep your blaster revved without actually firing.

Again, assuming you could rig a non-canted cage to fit, running the Hyperfire conveyor motor on 3S can start to cause issues. People have done it (and even replaced the motor with something like a MTB Rhino) but it doesn't always work well (probably more to do with Hasbro QC and manufacturing tolerances than anything else).

RM2s use brushes made of stamped copper sheet. Before too long they'll look like the brush pack on the left (that's from a Rayven motor running on 3S but the RM2 brushes will do the same in an even shorter space of time on anything other than 4 AA cells).
Boff

Solid core has its place but not in Nerf power applications. I'm using it a lot on the Arduino project stuff I'm working on at the moment but as others have stated, stranded wire for Nerf is the only way.

I think the whole lesson of this thread is that asking questions ahead of time is the best way to do things. We have the Vault now to make sure that the latest and accurate information is collated in one place for reference.

I think I might create a Vault archive request thread in there so people can ask questions that then get answers codified or linked in Vault threads.
Franksie

My advice would be listen to experienced hands like Old Noob and SSGT - learn from their mistakes rather than making your own and don't cut corners.  You're asking for advice but you're not sounding too receptive to what you are being told.
OldNoob

Franksie- Kids know everything, they just ask us old guys to humour us.

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