Help me understand my Emaxx
 

Hey all, just got my first monster, an Emaxx. I plan on using maxxamps 2 cell 6000 packs. On this site when someone says 2s or 4s regarging the batteries for a emaxx are they talking per side or for the vehicle as a whole. In my head I see it in terms as per side thus 2s. In another post someone referred to the truck would need 4s. Im just assuming were talking about the same thing.

Here is the link Im refering to:
http://www.rc-monster.com/forum/show...?t=4593&page=3


I assume the esc is seeing this as a total voltage an pumping the same voltage to both motors ,14.8+? And the stock ESC has a low voltage control setting??

I have a 1/18th scale RC18T thats converted to brushless w/mamba stuff. I run a 3cell 11.1v on it. So Im a bit confused on the twin motor setup and how it works.

Assuming I get 2 6000mah 2cell packs , I will/could combine them into a 4s pack for a brushless setup. Define using the packs I just mentioned, as a series and a parallell connection and what that gives as a result(I can never remember)

thanks again

Joel

You will need a new esc with LVC or buy an outboard LVC for use with the stock esc.

The voltage will "add" and become 14.8v (4s) since the packs are in series.

BTW, welcome to the forums!

Thanks, that helps. Is there a generic diagram that shows a series and paralell connection? thanks for the welcome, Ive had a couple here and none on some other fourms

J.

Yes there is!

Brian G's calculator has a wiring diagram page! It's very cool really.

I'll look for the link and post it here in a couple minutes.

http://www.scriptasylum.com/rc_speed.html

I'll through out some other questions that I have. I'm trying to understand the pack configurations a little better. A 2s2p 6000 pack would be 2 cells in series and 2 in parallel, 4 cells total, to double the voltage and double the amperage?

Man Im getting confused.

Yes! That is correct!

Great, So what is a supermaxx.

Supermaxx is a Brand Name of "Top Quality" T & E-maxx parts from Unlimited Engineering. They make some AWESOME products. Check out the site: www.unlimitedengineering.com

So gorillamaxx is the same, aftermarket parts for the t/e maxx?

sorry for all the basics, Ive been doing a lot of reading but still some confusion here and there.

J.

The Gorillamaxx is similar. they offer chassis', suspension components, and single speed transmission conversion kits (typically used with brushless).

UE makes the best suspension parts IMO. G-maxx makes the best racing chassis.

Got it. So for a great Emaxx basher(I dont intend to race, just play around the house/park ect..) on a minimum budget of quality and necessary parts whats the short list and rough cost. If this has already been discussed you can just post a link.

bump??

Well, a good and beefy maxx would look like this;

FLM 1/8th bulkless conversion (about 120)
1/8th diffs (about 100)
RPM arms (about 48)
FLM chassis (90)
FLM shocktowers (50)
traxxas big bore shocks (65)
stiff springs (20)
UE cvd's (110)

Or you can go for this;

traxxas 3.3 t-maxx arms/shafts/kncukles/bearings/turnbuckles (i got a set for about 70 bucks on ebay)

FLM bulkless conversion (120 per set) 7075 maximizer dif cups (50 for two) FLM towers (50) FLM chassis (90 bucks) bigbore shocks (65) stiff springs (if needed) about 20

that would make a fair cheap, yet rather durable conversion.

Serum, I wouldn't recommend RPM arms with the CVD's since they like to pop out...I would go with:

FLM 1/8th bulkless conversion
1/8th diffs
FLM a-arms
FLM chassis
FLM shocktowers (I would add a wing as well)
Proline Powerstroke Shocks

OR

FLM combo bulks
Maximizer diffs
RPM a-arms
Traxxas 3.3 conversion Serum mentioned
FLM chassis
FLM shocktowers (I would add a wing as well)
Proline Powerstroke Shocks

i never had a cvd popping out with mine.

and where to get the powerstrokes for a reasonable price and new squee? as you know, they are obsolete for about a year now.

You don't have to rush into it all at once. Since you plan to run the titans
for now. I got the pics of how to wire the lvc up to the evx. Just do a
search.

Are these the shocks your talking about?

http://www2.towerhobbies.com/cgi-bin...?&I=LXHKB4&P=Z

Thats them, well 2 of them. There are supposed to be 8 total. 4 of the ones you linked, and 4 with springs. I believe theres a set on Ebay right now...

Not sure Im following. Are you saying I will have 4, 1 on each corner without springs and 4 more of the same except w/springs on each corner also?

The one with springs are a little different.
But you will have 4 of them kind one per corner.

I just won the auction on ebay. They cost me $90.75 shipped, is that a deal?

I read on one of the descriptions that they are no longer made, is this going to be a problem from a parts standpoint?

Yea, that was a pretty good deal. As for parts, I wouldn't worry about it...

yea it should last you and i think tower hobbies may have parts...?

Maybe...

Are they re-making them!:)?

Where did you get that from? :p

The only thing Ive saw on tower is the bypass shock. Cant say Ive looked for any other parts for them, I'll check it out.

i dont know it may be?

I've noticed a few times that my emaxx will suddenly go into reverse on its own. the first time it might just glitch backwards. Then it will get to where it wants to creep slowly backwards steadily. Today I was hauling grass across the yard when it applied reverse on its own and sent the truck in to a tumbling fury = / What is going on?

Could this be the LVC kicking in(I have a dimension engineering one)? Is this a sign the tx batts are getting weak?. Im using the stock traxxas tx and the light is still bright red, not sure if it changes on low batts or not.

It seems to happen only when my batteries get down to 7.4-7.5v.

I don't know how that lvc works.
I have had a lvc go wide open reverse on me.
Well the batts are 7.4 at stand still. But with load could fall to 6v.

Is it an programmable/adjustable LVC? If it is, that may be the issue.

Try using profile 2 on the ESC (assuming you have the stock EVX), this eliminates reverse and makes you only have brakes. This should fix the problem.

The issue is that the EVX goes straight into reverse once the motors slow down enough, so any extended brake signal results in reverse.

I have a similar problem with my 18T. My Spektrum Receiver's Failsafe is set to brake slightly, but since it usually takes a second or two to kick in, its enough delay for the Mamba ESC to unlock reverse (its programmed to unlock reverse after the trigger has been in neutral or brake position for two seconds - must be returned to neutral if it was in brake). This usually throws it into a reverse spasm.

Fortunately, I've never lost signal with Spektrum, but I am going to have to re-program the ESC or reset the failsafe to solve the problem (either lock out reverse or set failsafe to neutral).

For now, I dont have to worry since I cut my antenna in half...I'm going to get a new one soon and solder it on.

Do any of these LVCs have a little adjustment on them? Like a SM potentiometer? If so, that would set what the LVC sends to the ESC when it cuts off. Obviously, you want neutral. :)

You were running lipos on the evx wernt you? Did you not use a lvc? Anyhow I ran the truck some more with the starting voltage at 7.6 and ran it to 7.2v. No reverse experiences this time. I did get a lot of stuttering at a stand still then wide open throttle. I assume this is an overdraw of current that the batts cannot supply?

As far as Im aware the lvc is not programmable. Im gonna shoot dimension a email about the issue to see if this is what it is.

Yep. That would be the cause of the stutter. I just ran mine. When it got low
it would let me know. Stutter some to show low voltage.

Here is what I sent dimension engineering and their response:

Hi, I bought a liposhield for an emaxx monster truck. Im using 2 2s2p
> 6000mah 7.4v packs. When the liposhield \"kicks\" in what should be
> response by the vehicle?
> I\'ve had a few instances where the truck wants to run in reverse on its
> own, or running wide open and it suddenly applies full brakes. The
> functions of the esc are foward/brake/reverse, with a slight delay between
> brake and reverse.
> Also when the batteries are getting low I get a \"stutter\" upon a
> standing start with wide open throttle. Is this a function of the
> liposhield?


Hi Joel,
LipoShield is mainly aimed at r/c planes that have a throttle going from
0-100. When in cutoff, the throttle will slowly be scaled back towards the 0
position, in proportion to the battery voltage. In a car configuration,
you'd typically have 50/50 throttle or 30/70, so the 0 position will
correspond to a full brake or reverse. Unfortunately there would be positive
feedback in this situation - if the battery voltage gets low, the car starts
driving backwards which will lower the battery voltage even more. Basically
if you want to use LipoShield/Cellshield on a car, when you start getting
odd behaviour it means that the battery is drained. We do have an upcoming
product aimed at cars that will have a throttle rollback better suited to
cars/boats - it is in beta testing right now.
Please let me know if you have any more questions!
Best regards,
Hisham Sakr
Dimension Engineering

So it is designed for planes. That explains the reverse for sure. If you see any thing of a stutter or such. End the session. That is what I did on first one
i had.

For the most part Im not really satisfied with how this lvc is working on the truck. Im likely to take a strong look at the car one he mentioned when availiable.

If Its cool with everyone, I'm going to continue to use this post for other general questions pertaining to my learning my way around the truck and making changes rather than post all over the place. I think it will better serve(myself,& other new commers) since it will deal with a lot of the basics on making it brushless worthy.

My next question is the installation of the 3.3 arms, turnbckles, carriers and slidershafts. Ive noticed that there seems to be a front pair and a back pair. Where the turnbuckle mates to the carrier, there is a link, but Im not sure what its called. Some sort of pivot ball. Anyhow one set set(turbuckle links) is mounted in the center of this pivot ball and the other set is mounted in the same fashion except its on one extreme end of the pivot ball. In the pic which end of the truck does this one go on and what is the orientation?

thanks, J.