Wow
 

Hi guys!
just ran my car in the park for the first time and i am amazed its pretty fast but has so much torque! and the runtime is fantastic
heres my setup:

e-revo
MMM combo
22/65 gearing
2x 3s 5000mah neuenergy lipos

here are some pics of my car:

http://i80.photobucket.com/albums/j1...0/DSC00033.jpg

http://i80.photobucket.com/albums/j1...0/DSC00032.jpg

http://i80.photobucket.com/albums/j1.../DSC006030.jpg

but i have soo many questions! i actually cant believe how many ive managed to rack up this time!
i dont expect answers to all of them! i just need a place to write them down permantly somewhere so i can refer back to them some of the arnt even questions, mearly statements of surprise lol
ok here i go:
(in no particular order)

1. I cant seem to fit the gear cover onto the top of the gears where it should go (i have the single motor mount). i can get it on, but it is really hard to, and once its on the spur gear keeps rubbing against it. is this part really necessary, or is it safe to run without out?

2. this really surprised me: i have two 3s 5000mah neuenergy lipos lasting 40 minutes with still 3.81-3.82v per cell in them! I charged them up fully before i went out, but once i was out it was proper hard running, speed runs and everything! and these lipos lasted for at LEAST 40 minutes. i say at least, because after 40 minutes it got dark and i had to go home. I hook the lipos up to the charger and each cell has around 3.8v still left in them!! not even close to the 3.2v LVC that i had set. This really amazes me.

3. brianG's speed calculator says i should be going at least 50mph, but it seemed like it was going 40-45mph. no matter, still pretty fast!

4. I just have velcro holding down my MMM, and i did some pretty wild sumersaults and its held on fine, no need for zip ties!

5. during and after my running session, i constantly felt the MMM, motor and lipos. during the entire session, the MMM and lipos were cold, and the motor was barely warm, even with continuous speed runs. amazing! i dont understand how people are getting such high temperatures.

6. should there always be a spark when connecting lipos, cos there isnt anymore, but there used to be when i connected them a couple of days ago.

7. how does the MMM let you know when the LVC is kicking in?

8. as the lipos are used in a session, does performance decrease steadily, or is it a sudden drop in performance once they reach a certain point?

9. the next time i drive, i will run the lipos down to the LVC of 3.2v per cell. after i done this, when i get home, should i charge them up to 3.7v per cell? or should i just fully charge them to use next time? or should i just leave them as they are until next time? is there a way i can program my hyperion charger to just charge them up to 3.7v per cell?

phew done!

I tried to answer what i knew, I don't know much, LOL :lol:

1: try a heat gun on the cover and push it out a little. mine rubbed a little too. Heated it up and noe its good.

2: great to hear that you runtimes are that good!!!

3: His calc gives a great estimate. Its been really close on every thing but the lst.

4: just be careful b/c the case can open up on you

5: geared correctly the castle motor runs really cool on 6s. Looks though you found the sweet spot!

6:The spark is from the power capacitors chargeing. Its normal and ok

7:it slows the truck down alot.

8: you wont notice any decrease in you power using a good lipo until they are dead! they dump quick. If your battery lasts 40 mins max you will have near the same power at 1 min into it as the 39th min.

9: only charging to 50%(store mode) is only if you are not going to play in the next two week. If you are going to play again in the next two weeks fill the battery up!


HOPE THIS HELPS!

1. Might not fit with some pinion & spur combos due to the large diameter of the gears- I wouldnt worry, 99% of us dont use gear covers and I've only seen one case of a stone getting caught and killing the esc as a result.

2. Lipos = win :yes: Bear in mind resting voltage will be higher/rebound a little than when you are running the truck.

3. I doubt your eyes can tell the difference between 45 and 50mph :lol: I always thought my hvmaxx setup was pushing my gmaxx along at ~35mph, but in reality it was only ~20mph, once I did the sums on the calculator. You need a GPS or radar gun to get an accurate idea.

4. Good for you, but make sure the velcro doesnt come unstuck from the chassis (I would get the optional holddown when its released).

5. We're in the UK dude, its like 2*C outside! I would get a proper IR temp gun though for accurate readings, but your findings so far are excellent.

6. The caps on the esc will hold a charge for quite a while, so they wont recharge every single time you connect the lipos, which is nice (sparks make me nervous, reason why I didnt want to learn how to weld at school...).

7. Truck stops moving. Sometimes it may become jittery on the throttle, or so people say, but usually the truck will simply grind to a halt. You will see it slowing down as the lipos begin to dump though, so you will usually stop running the truck before the lvc kicks in.

8. See above. the discharge curve of lipos is very flat until the last 30 seconds or so.

9. Depends. If you plan to use the truck again in the next few days or so, then charge them up fully. If you dont plan to run it for a week or more, then a 'storage charge' of ~3.7 volts or so is recommended. You should have that feature on your hyperion, if not you can simply stop the charge once the voltage of each cell is roughly 3.7v also- you should be able to see the individual cell voltages if you press the right button during charging, see your manual.

Fun fun fun... :yes:

I can only help you with #9, from my Hyperion Duo manual-

ALWAYS store your packs at 60% of capacity. After a day of flying (uhhh... driving) use Store Mode to acheive this.

It is especially harmful to store lithium packs fully charged, and should be avoided for a day or two at most.

..... There ya have it, right from Hyperion.

The other guys answered your questions pretty well, but I want to interject my $0.02 about #6. There should always be a spark when hooking up the your last connection because the caps are always discharged when you remove the battery.

Depending on which ESC you got: a "true" V3 with wires directly soldered to the PCB, or an V2 upgraded to V3 with connectors on the PCB instead.
What might be happening is that the first couple/few times you plugged the packs in, you ablated the heatsink on the MMM. The heatsink is VERY close to the power plugs, sometimes even touching. When you plug the batteries in, the heatsink shorts out the pack for an instant and basically vaporizes the itty bitty contact area between the heatsink and connectors. After a while, all the aluminum is ablated away and you no longer see a large spark.

Or, your battery connectors could have gotten pitted from the sparking during the first few connections.

Or, you just got better at smoothly hooking up your battery connections, which helps reduce the spark.

Interesting...

With my V1, there is no heat sink rubbing issue, but Im always nervy about connecting up my lipos every time so my technique isnt smooth at all, so in theory there should be a spark every time for me too; but there isnt.

Would the caps always discharge every time you unplug the batts, or is it dependant on if you turn the esc off first (which I do), and also the location of the caps on the circuit- are they in parallel to any components that would drain them regardless of the esc being on/off or hooked up to batteries etc?..

The caps are hooked directly to the power leads. It has been confirmed that even with the power switch off, there is still current flow that can deep discharge your batteries. If it can discharge batteries over several hours, it can certainly discharge the caps over a few minutes. I guess there could be some residual charge on the caps. Maybe that once the cap voltage gets below a certain value (~5v), the current drain is minute. Then, that would mean there is SOME voltage on them and then won't spark as bad next time...

Practice makes perfect to make a smooth entry... :party:

Questions.
 

Hye there. It sounds like you have answers to most of your questions for the most part. Nice setup and congradulations on your success with the operation of your build. One added note on teh gear cover on your tranny. I used longer screws and placed nylock nuts on the screws first, which makes a small gap between the cover and the mounting plate. That took care of the rubbing issues for me, protects the gears from grabing any wires, and also gives you a little cooling effect for the gears during heavy useage. It works great and it is easy to install and remove just like normal. Good luck with continued success with your project.:lol:

Not to high jack the thread!.. (I'm sorry guys)

Jerry!! I wanted to put you builds in the (Best of the BEST 08) but I couldn’t find the thread. a little help please..

Thanks and sorry again..

My girls like it rough...:yes: :wink:

You mean the one you inflate?

No he is talking about Palmela Handerson...

And the bicycle pump does all of the work...

Here I go, gonna try to cover each one...

1. I cant seem to fit the gear cover onto the top of the gears where it should go (i have the single motor mount). i can get it on, but it is really hard to, and once its on the spur gear keeps rubbing against it. is this part really necessary, or is it safe to run without out?

I never use the cover, but I try not to run in a bunch of loose dirt or small gravel... The heat gun technique already mentioned is most likely your best bet...
2. this really surprised me: i have two 3s 5000mah neuenergy lipos lasting 40 minutes with still 3.81-3.82v per cell in them! I charged them up fully before i went out, but once i was out it was proper hard running, speed runs and everything! and these lipos lasted for at LEAST 40 minutes. i say at least, because after 40 minutes it got dark and i had to go home. I hook the lipos up to the charger and each cell has around 3.8v still left in them!! not even close to the 3.2v LVC that i had set. This really amazes me.

The reason the cells read 3.8 is that after you let them sit, lipos will reagin some voltage. I would say that 40mins is great with your setup, you may get a few more minutes than that before the lvc kicks in. Now you see how good 6s lipo really is!
3. brianG's speed calculator says i should be going at least 50mph, but it seemed like it was going 40-45mph. no matter, still pretty fast!

The erevo handles speed well, so you may be going faster than you think...

4. I just have velcro holding down my MMM, and i did some pretty wild sumersaults and its held on fine, no need for zip ties!

I would suggest meking a hold down plate and ziptieing the mmm to that plate and screwing the whole lot onto the chassis. The cases do come apart, no way to get around that (unless you glue it, and I would NOT do that)
5. during and after my running session, i constantly felt the MMM, motor and lipos. during the entire session, the MMM and lipos were cold, and the motor was barely warm, even with continuous speed runs. amazing! i dont understand how people are getting such high temperatures.

What were the outside temps?

6. should there always be a spark when connecting lipos, cos there isnt anymore, but there used to be when i connected them a couple of days ago.

Mine spark everytime, but only after sitting for a while between uses. If I unplug the pack and plug it back in within a few mins it will not spark. The caps bleed down till they are empty while sitting...

7. how does the MMM let you know when the LVC is kicking in?

It stops you running and if you look at the leds while pulling the trigger the yellow light blinks. You should still have steering, but it is time to stop and charge.

8. as the lipos are used in a session, does performance decrease steadily, or is it a sudden drop in performance once they reach a certain point?

Lipos hold voltage well until they get close to 3v per cell. After you run for a while you will feel the performance drop right before the lvc kicks. I never hit the lvc anymore, as I just stop running when the performance drops off.

9. the next time i drive, i will run the lipos down to the LVC of 3.2v per cell. after i done this, when i get home, should i charge them up to 3.7v per cell? or should i just fully charge them to use next time? or should i just leave them as they are until next time? is there a way i can program my hyperion charger to just charge them up to 3.7v per cell?

Good to charge them back up, at least to half capacity. I have always charged mine fully and stored them, but that is supposedly not good to do... No idea why, maybe the cells do not like it... Never had an issue though.

Stop picking on me, its not my fault girls dont like me as anything more than just a friend. :cry:

Take a few dead presidents with you next time. :wink:

Save your dead prez' for RC stuff. Being a girls "friend" means you're always around when she needs someone to talk to, inevitably you're bound to score. Better still, with your wallet still intact.

Nah, they are all mingers... you are better off wating for the right one...

Hmm, hookers in the UK may not want american money, the euro is strong right now, so exchange rates might screw you over (no pun intended). At least we have a better idea what Brian G spends his non-rc money on. "5 dollar make you holla big boy!"

Hmmmmm and we wonder why they dont let him on the traxxas forums anymore.

HAHA, thier moderator are power hungry gits...

Luckily we have moderators who are not afraid to throw in a few good jokes! (and damn lucky to have me posting here frequently)

I miss those days. I remember just about every response he gave cause all the questions went like this.

Question - Hey Neil, I want to build a dual motor velineon emaxx.

Answer - What the !@#$#$%$^&* planet have you been living on. Everyone and their mother owns on of those and they dont work worth @#$%@^@$%. Did you steal my blowup doll, you !@#$#@$%$&.

Yep the good old days.

Yeah, but being just a friend puts you in the "friend zone" and she'll never see anything more than a male version of her girlfriends.

Nah, I don't have problems in that arena. And anyway, 5 dollars?!? I'd be afraid to get near someone who is that cheap!

Delusional are we? :wink:

wow thanks for all these replies guys, its great! i also posted this on the traxxas forum and got 1 reply! :lol:

the outside temp when i was running was about 5 degrees C maybe? not sure...

about the batteries, i thought 8000mah was meant to last you 45 minutes, and 5000mah about 20-30 minutes. that was the downside of running 6s in the e-revo. i cant understand how my runtimes are that good. im gonna take it out today to see if it was a fluke!

I got the MMM combo, but the MMM has bullets all round, including the battery side. both bullets are touching the heatsink, and i am afraid of breaking them if i try to pry them away. does this mean they are shorting out my lipos? i remember hearing that CC insisted it wasnt a problem

I beg to differ Brian G. In S. Florida, the "friends zone" is where it's at. No strings attached and better "service" than Castle Creations!

Warrenty
 

I got the MMM combo, but the MMM has bullets all round, including the battery side. both bullets are touching the heatsink, and i am afraid of breaking them if i try to pry them away. does this mean they are shorting out my lipos? i remember hearing that CC insisted it wasnt a problem

This sounds to me like a problem for sure. Do a continuity test and see if you have a short on the heatsink. If so then drop Castle a few lines and send it to them for repair/replacement. Seems easy enough to me.

that is no problem, if it does cause an arc then it will immediately burn away the connecting material and leave you good to go

huh? sorry that last post was beyond me lol. are you saying i should just keep running it as it is? will it damage my lipos?

cheers

Wont damage the lipos- read BrianG's explanation further back and it should become a little clearer.. or not... :smile:

Well that's a different "friend zone" than I am talking about. I am referring to the zone where she thinks of you as one of her g/f's, not as a romantic (or carnal) partner.

DO NOT attempt to pry them away. The only thing you will succeed in doing is breaking the PCB and that's bad (and probably not covered under warranty).

Castle has indeed said that's it's "no big deal", but I still disagree. But I am just a hobbyist with only 4 years of electronics school, and about 15 years of experience. The Castle guys are real engineers with much more experience.

Sorry. I do try, but tend to get wordy. :oops:

hi guys

just got back from day 2 of running, and this time my results seem more normal. runtime was about 30 minutes, which is still very good for two 5000mah packs.
MMM was warm, but the motor was hot. i have a handheld temp gauge but it was difficult to take readings with the body on, but i did my best. it was 120F, so i know i have not damaged anything. would it be better to get one of those on-board loop temp gauges by traxxas that i can just wrap round the motor? do those work well?
top speed was around 45-50mph with 22/65 gearing.

heres the thing im concerned about. This time, i ran the truck till the LVC cut in. The MMM stops the trottle when i try to accelerate, so i figured this was the LVC. no sounds or lights or anything, just throttle interuption.
anyway, so i stop running and hook my lipos up to my hyperion. i have the custom LVC set to 19.2v, thats 3.2v per cell just to be safe. I look at the first lipo, and sure enough each cell is about 3.2-3.3v. all is good. i look at the second lipo, and two of the cells are 3.2v, but one of them is 3.0v?? whats up with that? Technically the MMM LVC should have cut in sooner because the overall pack voltage would have been lower than what i programed it to cut off at. I am a little concerned now... not too concerned though. 3.0v is still ok right?

What i think i'll do now is charge both lipos up to 60% because i wont be driving it for a few days.

3.0V is still okay and so was your temp of 120F.

By handheld temp gauage you mean an IR heat gun (the type you point at an object then press a button to get a reading)? Dont be affraid to stop for a minute or two to take off the shell and get good temp readings (I have a whacking great big hole in the rear of my shell for said purpose). Dont be too worried about the cell voltages being slighly uneven either, I get the same thing with my A123s and zippy lipos; the safest minimum voltage for lipos is about 2.6-2.8v per cell. You wont get any warning lights or sounds either as the MMM has no way of making sound- the chimes are generated by the the esc pulsing current through the motor at certain frequencies to generate a high pitch buzz, and it cant do that & spin the motor at the same time.

You worry too much... :wink:

i know, its not healthy... lol

thanks for that bit of info, but i think you are wrong about the MMM not being able to make sounds. otherwise, when you turn it on, it makes sounds, but the motor does not move.

also what would you say about the on board temp gauge, are they any good?

thanks alot for your help

Wrong- how dare you question the word of a BL God! :diablo:

Disconnect the motor from the esc, then try turning it on- you will suddenly find there is no noise at all. The motor doesnt need to spin to make the chimes, its the frequency of the current through the windings that generates a sound- its not done in a way that makes the motor want to spin. Trust me, or just ask BrianG etc. :wink:

Anyway, the onboard temp gauges with loops look pretty good, you just have to find a way to keep the loop around the motor (a finned can would be handy), and then you can monitor the temp at the push of a button, and record maximum temps etc with different gearing. Wouldnt like to recommend a specific brand, but Im sure a little searching around will yield answers- they are normally used on nitro engines, so thats a good starting point.

Neil is right (that actually caused me physical pain to say! :wink:). The motor doesn't turn. The ESC is probably sending pulses to two opposing phases at once to keep it from moving. However, I have seen the motor move slightly when it beeps, but it seems to depend on where the rotor is sitting at the time.

o right lol i surrender to your r/c knowledge! i think i will grab myself one of those on board temp guages, they seem pretty nifty