TambokGT

If it turns hot then it's on the brink of crapping out on you.

Donnie-D

Tell me a little more about this Fail Safe.

What does it do...?

How does it work...?

How big is it...?

Where does it mount on the car...?

Will it add a bunch of weight to my car...?

Thanks!

Turbo9000

iTrader: (5)

dang it...there goes another servo... but on the upside i found my hitec HS-925mg hi torque at the bottom of my junk box and it still works perfectly.( i have no idea how it got there) that was my mbx4's steering servo

popsracer

Got a question on Fail safes.

What happens if the battery voltage drops too low to run the servo. Is the Fail Safe going to detect low voltage BEFORE the servo quits working.
I had a battery pack fail during the Main and the only thing that saved my Car was a good strong throttle return spring.
Was really my fault, I charged the pack the night before the race and didn't bother to read the display numbers before pulling the pack off the charger. Turns out it only got about a 300 Mah charge, just enough for practice and 2 qualifiers. Bought a NEW pack the next day and turns out it was BAD too. What luck!

InitialD

Most of the time yes. The fail safe detects and kicks in when the voltage drops to 4.?? V. Just enough to lock out your servos.

Then again if for some reason you receiver pack dumps suddently, the fail safe will not save your car... Just like when the receiver pack connector gets cut off. This is the only time when the TRS will save you.

Boomer

That's what they're designed to do - return everything to whatever neutral you set at a cut-off that is still able to run the servos.

Supposedly, even if you have a quick dump, it should bring a neutral setting since it takes less than 1/10 of a second for most of our servos to travel half their full distance (or to center).

But that's the best argument for both a return spring and a failsafe. . .

jason102276

i am using a rubber o-ring around my carb for a throttle return spring works really well on slide carb

i wrap it around carb opening then stretch it over the lever

i want to get a failsafe also because a throttle return spring wouldnt help if i got glitched by another drivers radio

at the same time i wouldnt want to only rely on the failsafe cause if i wrecked and battery came disconnected it wouldnt return the throttle position

but in all honesty i only ever used a throttle spring for a couple races after sedan nats cause they teched them but there has been at least one occasion when these things could have saved me some loot

this year i am going to be more carefull

i had a crystal fail on my ko radio and the servos both went completely nuts i was lucky it didnt burn out my hitec digitals(not known for their reliabilty)

BOLISARIO

iTrader: (57)

What size O-ring and where could you get them?

jason102276

it was aprox 1/2in in diameter as long as it has to be stretched

i work in a auto shop so i just took some but it was an auto a/c o-ring that could be got at any auto parts store it was green i think the color is cause it is for a/c some are blue

i used a rubber band at nats but the rubber band is affected by nitro fuel so after a while it will break the a/c oring is meant for applications with refridgerant oil and freon so it should be able to stand up to the nitro fuel

Turbo9000

iTrader: (5)

An o-ring... thats a good idea.. it'll surely outlast a rubberband.

simonfdr

I think you should have both. Fail Safe when radio goes out of range, the Return spring for when the battery decides to be a little bi*ch such as popping out.

popsracer

A fail safe will NOT work on a dead servo. A return spring will pull it back to neutral. I think an O-ring is way stiffer than needed. Just change the rubberband every month or so, as part of your pre-race inspection and set-up.

simonfdr;

If your having problems with batteries poping OUT, your not securing them properly.
------------------------------------------------------------------------------------------------------------------
Obviously you can NEVER be 100% safe.

An Experiment:

Try removing the Receiver Xtal at full throttle (engine off) and see if the FailSafe pulls the throttle servo back. I'm curious to see what happens.

ant

ive tryed failsafes but found running a hitec 925mg steer
and a hitec 625mg throdle the current draw activates the failsafe
now it sits in the pit box.
got the mtx3 setup even with total loss of power or servo failer
it will return to newtal and aply a small amount of brake
just with the right linkage setup.

CRASH

iTrader: (26)

What fail safes due you guys run, besides the throttle return spring. I know that in my XXX-NT with Futaba S9402 servos the throttle return spring is not strong enough. With my NTC3 I definetly am considering one. Either the spring or an actual fail safe unit or both. In my RC Boats I use a Futaba radio with PCM but for cars I use the M8 and unfortunately they do not offer PCM at this time. PCM is a great failsafe.


Thanks,

Turbo9000

iTrader: (5)

I use the newer dynamite unit. Ive had no problems with it.