My e-revo brushless edition build

[jpoprock]

Originally Posted by mistercrash

And finally, the rear body mount brace I made with a carbon fiber rod broke. I was jumping the triple in the back stretch and while the truck is just leaving the jump, I notice a marshall in the middle of the path of my ERBE so my reflex was to apply the brakes.... in mid air I landed very badly with the back of the truck hitting the ground first. That is when I broke the brace.



This goes to show that a brace is needed to keep the rear body mount from flexing too much when running a rear wing. Without the brace, it might have been the body mount or even the chassis breaking. I made a new one using a spare steel P2 pushrod.

So... do we know yet what LENGTH the rod needs to be in order to fit from the shock mount to the wing? I have a ton of these, and they are either too long or too short. A proper measurement would help, cuz I would like to get some to try!

However, if you do take a hard landing on the wing, doesn't that then just cause more stress and pressure on the shock mount, possibly causing it to rip itself from the chassis? Or bust a bulkhead?? I'd rather lose a wingmount then to destroy either of those!

[shaunjohnson]

look at the revo design....you are not going to rip out the shock mount!!
even with that brace in place the weak link might still be the brace or the wing mount but i highly doubt it's gonna take out the shock mount.
he said it's a P2 rocker pushrod if that's any help.

shaun

[mistercrash]

Originally Posted by jpoprock

So... do we know yet what LENGTH the rod needs to be in order to fit from the shock mount to the wing? I have a ton of these, and they are either too long or too short. A proper measurement would help, cuz I would like to get some to try!

You sound mad for some reason. The LENGTH of the rod will change depending on how you fabricate the part that goes on top of the shock tower to secure the rod to. I didn't measure anything when I made this thing. I made the CF part that goes on the shock tower and used that same shock tower as a template to make the holes. Once it was installed, it was just a matter of filling the gap between that part I made and the body mount. I used an old style P2 pushrod that was all aluminum and put a few more threads at each end and cut the excess to make it fit.

Originally Posted by jpoprock

However, if you do take a hard landing on the wing, doesn't that then just cause more stress and pressure on the shock mount, possibly causing it to rip itself from the chassis? Or bust a bulkhead?? I'd rather lose a wingmount then to destroy either of those!

The rod ads strength and rigidity to the body mount but the rod is still the weak point. Either the rod will bend (or crack in the case of the CF one) or the ball ends will be pulled out. I have seen aluminum chassis' that were bent upwards and those bulkheads ruined because the M4 screws were pulled out of them when the chassis bent. That rod is a mod that was brought to fix that problem, it has proven to work very well ever since rear wings were introduced to the Revo.

[shaunjohnson]

Originally Posted by mistercrash

I have seen aluminum chassis' that were bent upwards and those bulkheads ruined because the M4 screws were pulled out of them when the chassis bent.

been there done that, did your threaded insert mod and i'll never go back
one of the best mods for revo ever those threaded inserts!!

[jpoprock]

I sounded mad? Sorry about that! I wasn't mad at all. Just goes to show how sometimes text can be totally misinterpreted! I'm never "mad" really!

No, I had remembered once when removing my shocks from my ERBE, that one of the long screws that screw down thru the top of the mount, never seemed to "bite" and come to a noticable stop. I had forgotten that I simply changed to a longer screw! So, when I posted that, I had forgotten that I did that, wondered if the pivot of a rear end lid slap might pull the mount from the chassis, but yer right, that's not going to happen.

Good call on the pivot ball popping out or the shaft snapping.

My frustration in finding the right length shaft was true though. I could have swore that i had some P2 Pushrods, but these aren't I guess. I thought I had them with me today, but they must be at home or else I'd look to see what mm is printed on them. That's why I was asking for the length, so I didn't have to go to Traxxas to look up what length the P2 rods are. But I will do that, so no need to worry about it.

Thanks!

[Kevlar]

I dabbled in bracing and haven't broken a rear upper assembly since, but did learn how to drive more gooder, and this is what I was doin':



I did have quite a few crashes with this setup, and the worst thing that happend was it popped out of the hole I drilled in the vent, and have had to drill another hole and lost a few screws, but better than replacing the whole mount!!! I used the stock push rods...


.......I love your build threads mistercrash....my revo wouldn't be what it is without your insight!

Here is another brace idea I ran across. I may try this way on mine. This with the combination of the single brace on the front side I believe would be indestructible. Maybe even a little overkill. lol

[suicideneil]

http://www.neweramodels.com/item.cgi...&part_id=10137

Not entirely sure how or where it fits though, but it looks nice

[mistercrash]

It looks really nice but like you said, where does it go? It looks really super duper uber heavy duty.

Remember what I did to my Racers Edge servo horn in post #20, well my ACE 1015 servo couldn't take it for very long. The Racers Edge horn is 3/4'' long and the mod I did made it 1'' long. The extra throw was nice and made the steering very fast as the servo didn't have to move as much to lock the wheels left to right but the extra leverage this long horn put on the gears was too much for my ACE. The same thing happened on my nitro Revo that had the same set up. So after replacing the gears in both servos, I went back to the stock length of 3/4'' that the Racers Edge horns had originally and this should fix the problem. The steering is a little slower but fast enough to satisfy me. More high end servos may have stronger gears that can withstand the extra leverage that a 1'' horn puts on the gears so I think it is still a good mod but you gotta have the servo to go with it.

[Bondonutz]

Originally Posted by jpoprock

My frustration in finding the right length shaft

[rawfuls]

Originally Posted by Bondonutz

HAHAHAAHAHAH

You would do that!

[mistercrash]

I received the rest of my 5.5 bullets today. I should find the courage to start soldering very soon. I put an OFNA rear wing on the ERBE because the Traxxas wing on my nitro Revo was broken so I needed another wing. The LHS had both the OFNA and TRAXXAS wings in stock so I went with the OFNA one because it just seems stronger. I put it on the ERBE and put the ERBE's TRAXXAS wing on the nitro Revo. I had a puffed Zippy in my battery box, it just puffed sitting there with the other lipos. I don't know what happened to it but both cells were badly puffed. So I unsoldered the connectors which I will keep and put the cells in the middle of the driveway and punctured both of them very hard with the tip of a long crowbar
There was some fizz with tiny sparks in the hole and a little smoke for 1 minute or two, then came the big puff of smoke, and I mean a lot of smoke and a lot of fizzing for about 20 seconds. But no flames at all. Then down to a little smoke and soft fizzing for 5 minutes and then nothing. I let it sit there for another hour to cool down and tossed the cells in the trash once I inspected the cells to make sure that they were all consumed. I should've made a vid. It was a cool experiment.

Yep... Lipo pops always make for good video.. shoulda hollered!

[shaunjohnson]

i cant make lipo's go bang!!!
lets see....never had a genuine failure yet, both failures caused my ME and the rest were on purpose.
the maxamps cell i tryed to blow up...well....
dead short.....nothing
gave a single cell 12V and pumped it with 100 amps from a car batt...nothing
nailed it...nothing
hosed it..nothing
douced in some nitro and set it on fire....nothing!!!!

the ones that did fail were caused by gravel rash under heavy load, that one caught fire so i ripped off the top cell (while on fire) and tossed it away, saved the pack and now it's a 4s.

the other one was left plugged into the MMM so when the MMM died it took out the lipo too....no fire luckily cause it was in my car

Shaun.. You can't force current from a car battery.. It's a constant voltage source..

If you want to 'help' a LiPo pop, find a bug battery charger and set a 10A charge rate and hook that up to the battery... that should be more entertaining.. My guess, without trying, is that it should see 20+ volts...

You could also plug it into the wall...