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Andrew_Aitchison

choosing motors

Im looking to mod out a rayven by replacing the normal motors and adding a second set of flywheels further along. Ive seen both Rhinos and Honey badgers on sale for the same price and wondering why i might choose one over the other.
Plus im probablly going to use a few IMR's for the power source.
blindgeekuk

In that situation, I'd go rhino for the main motors, hellcats for the afterburner, but you wouldn't get decent performance from the rhinos on into, and you'd be putting the IMRs under such a load on the hellcats that they are likely to die... quickly...

For the cost to get a decent charger and lipo (go lihv and mosfet for hellcats), plus a rewire, your talking a similar price to get IMRs and a charger
OldNoob

You can't run Afterburnerz off IMR cells. Just the Rhinos is 16A, vs max discharge of IMR at 8A. Bad idea for duration, cell life and safety.
TBH a proper 180/Lipo single stage will get you from 130-150fps depending on wheels for lower complexity, greater reliability and with less demand on your battery,  for which the Rayven tray is notoriously small to begin with.
SSGT

Re: choosing motors

Andrew_Aitchison wrote:
Im looking to mod out a rayven by replacing the normal motors and adding a second set of flywheels further along. Ive seen both Rhinos and Honey badgers on sale for the same price and wondering why i might choose one over the other.


Rhinos on 3S (11.1V nominal) are effectively your de-facto 130 size aftermarket flywheel motor. You can use Honey Badgers on 2S (7.4V nominal) but for single stage flywheel systems they are, if anything, too fast (above a certain speed max velocity is more to do with dynamic friction and the amount of force the flywheels can apply to the dart than the overall speed of the flywheels) and IMO are better suited as a pusher motor paired either with a 2S motor, like a Mabuchi 3240 (Blade 180) or XP180, for higher-than-average RoF or a 3S motor, like a Rhino or Hellcat, for very high RoF (I believe the latter was Ryan's original vision for them). As noted a well tuned single stage system can easily achieve 130-150fps (39.6-45.7ms-1) which is more than you'll be able to use in most UK games (130fps with Koosh is generally the UK limit, which may become a hard limit depending on whether or not the new firearms legislation applies to flywheel systems, and well above the 115fps/35ms-1 Durham limit).

Honey Badgers do potentially have a use in multi-stage flywheel systems though. If you're using a classic "afterburner" setup (second stage more than a dart's length down the barrel) then you can use a Rhino first stage and a Honey Badger second stage. If, however, you place the second stage directly after the first stage it's possible that you'd need Honey Badgers on both stages since, if the dart will be in contact with both sets of flywheels at the same time, the running speed of the  first stage has to be greater than the critical speed (the speed above which the dart never achieves static friction with the flywheels) of the second set. Depending on your flywheel and cage choice Rhinos might meet this criteria but if the overall setup achieves more than 170-180fps then they almost certainly won't.


Andrew_Aitchison wrote:
Plus im probablly going to use a few IMR's for the power source.


You'd need IMRs around 26650 size in a high current cell holder (or spot welded together into a pack) if you wanted to run a pair of Rhinos and a pair of Honey Badgers - larger if you wanted to run four Honey Badgers and much larger if you wanted to run 180 size motors (longer can and armature with the same cross-section as 130 size motors - usually produce more torque but also demand more current). The specs for most popular motors are listed in this datasheet (waiting for specs for MTB Wolverines). To ensure both safety and peak performance I usually advise aiming for a power supply that can meet the transient loads of the motors - i.e. it should have a burst (peak discharge) rating equal to, if not greater than, the combined stall current of the motors. For anything hotter than OEM motors you're generally looking at some kind of pack - usually LiPo but high discharge NiMH is also fine (although the lower energy density means it takes up more space for the same output). A rewire, along with decent switchgear, is highly recommended (for reliability if nothing else) with standard motors on IMRs but is effectively a requirement with higher current draw motors.
mipevi

Running four 14500 IMRs in a 2S2P configuration should let you comfortably use stock elite semi-auto motors for the 1st stage and Rapidstrike motors for the 2nd stage. You'd need to rearrange the battery holder using leaf springs for the negative contacts. Performance might not be quite what you are looking for.

Or use better motors and packs, unless you want to mount twenty 14500 IMRs onto your blaster.  Mr. Green
Andrew_Aitchison

Thanks for all the info. If I can get up to 130 fps on one cage, even with barrel drag then I wont put a second cage in.
I suppose ill go for Rhinos and a lipo then.
Thank you.
mipevi

I think 130 FPS is very unlikely, the Rayven's barrel is just so long. A Falcon 3S setup got close to 100 FPS average with Koosh.

For the performance you want, an afterburner seems necessary. I will be looking into integrating a Barricade front with a Rayven, mounting LiFePo4 packs on the inside of the blaster. This project will take some time, and I have higher priority modding to get done first though.
OldNoob

Those 100fps figures were without worker wheels. Faux barrel that length is 3-6fps off the average as a rule.
The Rayven cage and general alignment is more difficult to set up than the Stryfe and Rayven wheels are not as good either.
SSGT

Flywheel cage alignment is definitely an issue with the Rayven and is quite likely why it often underperforms over the chrono. Fixing it by shifting the cage is doable but really is a PITA - in most cases you can just add a small shim to the top of the magwell to move the top of the mag over to one side and ensures the darts are centred on the flywheels.

The Rayven barrel is a little on the long side but only slightly longer than a RS barrel and, IIRC, it's slightly shorter than a Recon/Retal barrel.

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