Archive for BRIT NERF Home of the British NERF Community
 


       BRIT NERF Forum Index -> Q&A and New members
Kurgan

Help with Rapidstrike wiring (Foam data service's RS rewire)

Before I start wiring my Rapidstrike, I wanted to check with the experts.
I'm putting 3x MTB rhinos in my RS and rewiring. I'm trying to go by FDS's rewire videos, but I'm a little confused about which wire goes where. I tried to map the connections out but I feel like I'm screwing up somewhere. Can someone help me out?
SSGT

Looks good to me, just make sure the flywheel motors are orientated correctly (for most motors mounted in a RS you want the bottom motor to be wired with forward polarity, i.e. red/positive wire connected to terminal with red polarity marker, and the top motor wired with reverse polarity, i.e. black/negative wire connected to terminal with red polarity marker). The polarity of the pusher motor doesn't matter too much although I like to wire it so that the worm gear pulls the motor into the gearbox rather than trying to push it out. As always, test the circuit on alkalines first - DO NOT plug a pack into a newly built circuit.

Since you're using a Rhino pusher on a live-centre circuit you may also need to play around with the position of the cycle control switch (and/or possibly voltage-drop diodes) to stop it from runaway firing - don't fix it in place until you're happy that it's cycling correctly (you have to test cycle stability with a pack as the pusher motor will likely spin faster on the pack than it will on alkalines).
Kurgan

Thank you. I think I reversed the CO and NO tabs though after examining FDS's video.

Do you think I should go with dead center instead? I'm starting out with a 9.6v NiMH for now because I'm worried about not correctly taking care of a LiPo with my infant son in my apartment.

I don't know what the preferred wiring is for 3x rhinos on 9.6v NiMH. Dead center, live center, etc..?
OldNoob

All you need to do with lipo is not leave it discharged or charge unattended. You shouldn't charge Nimh unattended either. I have two kids and a crap ton of lipo co-existing together. Just make sure they get put away charged at least to 3.6v per cell after a game and keep them in a secure place where the temperature is fairly constant and kids can't get at them, exactly the same as any battery.
9.6v packs are large and generally don't fit in the battery tray of a RS.
Kurgan

I don't doubt that it is possible. But it IS an unnecessary risk, albeit a very mild one, that doesn't need to be taken, at least for now. I can always go LiPo later, but since this is my first time I think it's an extremely good idea to take baby steps, regardless of the money or time it'll cost me.

The 9.6v NiMH I have fits perfectly in my RS tray with tons of room to spare.

But my topic is aimed toward properly wiring my Rapidstrike. I'm trying to find out if the above diagram's rev trigger microswitch should have the CO and NO tabs switched around (or any other immediately apparent fault), or if you think I should abandon it entirely in favor of dead center or another RS wiring method (in which case I could use a diagram or simple "wiring map" if you know of one).

So apologizes in advance for being a noob. I hope everyone here doesn't consider that such an offense. Thank you for any help.
OldNoob

If you own a mobile phone, laptop or tablet, all those have LiCo batteries and are statistically more likely to fail than a quality rc lipo. The myth that lipo is some how inherently dangerous needs to go away.
This forum is firstly concerned with safety in modding, we have pioneered many safety features such as better wiring, mosfets and fuses and if lipo was in any way unsafe we would not suggest it.
Good that you found a 9.6v pack. Post a link so we can check its power output is suitable.
Rev trigger way round is irrelevant, you can have the live feed to the NO and the blue wire to the motor on the Common and it will work the same. As long as nothing is on the NC you will be good.
Live centre is a good reliable loom design, I have found no added benefit from dead centre and it does sometimes cause less accurate cycle control. I never put diodes on the pusher either, if it's not stopping quickly and accurately use a better motor.

Being a Noob is not an offence to this forum, asking questions is important and the only way any of us ever learnt anything.
Franksie

SSGT

Kurgan wrote:
I'm trying to find out if the above diagram's rev trigger microswitch should have the CO and NO tabs switched around (or any other immediately apparent fault)


Yeah, don't worry, swapping C and NO on the rev switch it makes bugger all difference (you aren't using the NC contact so all the switch is doing is making or breaking the circuit - switches don't care which way the current is flowing through them). Like I say, the circuit looks fine otherwise.

A decent 9.6V NiMH pack should still run three Rhinos just fine and should they should still be spinning fast enough to yield maximum performance from anything but the highest crush flywheels/cages. Like Oldnoob (aka FDS) said, post a picture of, and (ideally) a link to, your pack if you're unsure it'll do the job - even though Rhinos aren't the most demanding motors, the appropriate NiMH pack will be significantly larger than the equivalent suitable LiPo. Even though they can take more abuse than a LiPo you still need to treat with a similar level of respect - at the end of the day they both can have a significant amount of energy stored inside them.

Kurgan wrote:
...or if you think I should abandon it entirely in favor of dead center or another RS wiring method


Best option IMO is to try live-centre and see what happens. If you can't make it cycle consistently then all you need to do to run dead-centre is to cut/remove the wire running from NO on the trigger switch to NC on the cycle control switch. The only other real option is 2-switch which works, and is nice and simple, but loosing cycle control entirely is a bit crude IMO.

       BRIT NERF Forum Index -> Q&A and New members
Page 1 of 1
Create your own free forum | Buy a domain to use with your forum