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Discussion Starter · #1 ·
Holy crap.... was having a wicked outing on the weekend with my mate racing our ntc3s. Wefinally found a cool spot with a position where we can get above the action...it was all good till a battery moved slightly in my TIGHTLY taped4 cell RTR reciever pack (contacts seem touchy ashell)and it was all over....for me anyways. I watched in silent horror muttering nothing more than "that's bad..." as my precious NTC3 almost careered away toward a thick ugly gutter responding to nothing....... needless to say things could have been a lot worse. It took off from the gutter and hit a warehouse wall about 6 feet up it and sat on the ground idling away..had it hit the gutter 5 metres to the right it would've taken a dive in a dam next the the factory carpark..... I've linked some pics of the damage I ended up with. I've seen it mentioned that NTC3s are considered fragile, but this collided pretty bloody hard and if the parts hadn't given where they did it would have been a lot worse, would've needed a new steering servo for one! Wound up needing to replace a snapped pivot ball, 1 wheel (obviously!), top half of the dif housing and I took the opportunity to buy a carbon front shock tower and a new front steering arm set just in case.The current arms seem straight but I'd rather have spares handy ratherthan getting it all fixed only to find it won't track straight! I'm thinking about buying the"FIX" too as in this situation it would've saved the shock tower and dif case, does anyone know if they're any good?


http://homepages.ihug.com.au/~mrbont/doh!.jpg


http://homepages.ihug.com.au/~mrbont/doh!!.jpg
 

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After seeing a few runaways I finally istalled the one that I have always had in my toolbox. It has worked a treat for me and stopped the truck quick smart as the power in my hump pack died.
 
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Discussion Starter · #8 ·
thankfully I was only half throttle when it cut out on me....... of course murphy and his law prevented it from happening in the braking zone.....


watching a car runaway is trully sickening, especially when it's yours!
 

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Fail safes don't save your car from every situation as they need power to operate.

An FS will save you from radio interference and low power but as they need electricty to detect any problem and turn the servo to hit the brakes, they can't do anything if a battery falls out, a wire gets cut or the throttle servo dies.

Get a failsafe and install it, but to protect against non-electrical issues, use a throttle return spring. It only needs to be a rubber band (inspected frequently for damage/wear) or any spring you can install. Just ensure that the tension is enough to pull the brakes on when there's no power, but not so much that it over works the throttle servo.

For slide carbs, best installation of a rubber band IMO is from the throat to the ball on the slide - that way it doesn't matter if the linkages fall off between carb & servo, it will still do its job.

Cheers!
Oggy.
 
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Discussion Starter · #10 ·
Duely noted! cheers! My ntc3 rtr came with a throttle return spring but it had way to much tension and was really hampering the performance punch wise as it slowed the servo, so much soI had to remove it...a rubber band is prob a better option as it'd be easier to get the tension right....I'm gonna buy a flat reciever pack anyways cos this 4 cell piece of junk holder had gotta go.......


the batteries might look like they're in but they won't fire up the servos.... all I needdo is apply pressure to a certain battery and it starts to work properly...I'll fix it for the mean time but I'll piss it off soon for the rechargeable pack
 

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Yep, failsafes don't work if there's no power. Also they can die if you spill fuel on them... great - lost throttle channel...



Throttle-return spring is your friend.


Don't use rubberbands for the return spring... rubber degrades fast with that engine's heat. Get a softer spring from a hardware store or go have a perv inside junk office equipment eg 'click' pens, dead printers & fax machines etc.
 
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Discussion Starter · #12 ·
what about fuel tubing??

i had fuel tubing on the throttle break link, and it returned to idle speed...



Nismo
 

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What about both
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I have both on my truck so incase the fail safe.. well fails.. then the throttle return spring should do the job, otherwise ill manually put the brake on.. and if the brakes fail ill try and steer it in my direction and grab it.


Lol id love to see all that happen.. itd be classy.
 

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Your wish might just come true!!



Spring on servo makes it eat more power. Extra gadget online also eats more juice. In total your AAs are gunna be drained faster...
 

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I have a 6V reciever pack and it usually lasts ages so it should be ok. How many tanks does it usually take you guys for your packs to go dead and the failsafes to kick in? Has anyone actually let their packs die and let the failsafe kick in??
 

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Ive seen Skidds failsafe work when his batts were flat, but ive been using a throttle return spring and its worked fine. The one time i took it off at Kilsyth it did a runner on me, that was the fastest ive ever run. Ive heard too many bad storied about failsafes to bother with one
 

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well i have a spring return (comes stock with xfactors) but im aslo gonna put a fail safe in it in a few days.. (wednesday- birthday)
but niick lol.. love to see your try and grab your savy at full speed lol..i would rather crash it into something.. or if ui can.. run it into long grass..or try and turn her as much as i can till she runs out of fuel.....one thing u dont wanna do is flip your truck on full throttle..and u cant control it lol.. your engine will kill itslef..









but yeh fail safes ar ea good idea.. and i dont wanna really test it out to se eif it works..lol
 
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Discussion Starter · #18 ·
The other reason I'm gettin one is in case I drive the thing outta range, or if something interferes with the car. Also should something outta the ordianary happen to your radio it also be a great help I spose. Might have to get a stronger throttle servo, cos the one I've got was struggling under the pull of the included throttle return spring..... would've saved me some cash had I left it on tho! I don't think a weaker spring can pull my servo back when the radio is of either.....
 

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These days you can also buy "digital" servos that can be programmed to return to a preset position if they lose radio signal = built-in failsafe.





But methink these things could do with a fuel-cutoff... ie no radio signal or no RX battery power, the fuel cutoff operates.


Just waiting for someone to build one!!
 

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What if you had a third servo, and made a small mount for it and connected the servo horn to a round peice of wire that was tied into a loop, then when the fail safe kicked in it would pull the wire around the fuel tubing...
 
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