Brushless MT project started

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.

flarcer

Well-Known Member
Messages
108
Reaction score
0
Location
Florida...70 degree winters
I've got a MT that I've started a brushless conversion on. I was doing a scratch build setup until I saw jwhites "big build" thread. I got rid of all my gas stuff, bought and installed the Kershaw kit and have questions about where to go from here. I have done 1/8 scale brushless conversions for years but 1/5 scale is new to me which is the reason for the questions.


My plans are to go with the Mamba XL setup. I see that jwhite used Castle plugs, connectors and cappack. Are these parts a must? I've used Traxxas connectors in the past, what about with this build?


(2) 4s lipo packs, what brand do you folks recommend?


What charger are you using?


Thank you in advance.
 
I'm converting to brushless, as well but it's my 5T. I'm going with the XL2 and I'm going to run the caps. From what I understand they help control ripple voltage, which can be hard on ESC's. The lower the ripple voltage, the better. As far as connectors, I really love Dean's connectors, but in this application they're not ideal. The battery and ESC cables are huge, so bullet connectors would be best. I've had great luck with Turnigy Lipos, and I'm probably going to go with a 6s pack from them.

I'm running a Turnigy Accucel-6 charger. It charges pretty much every type of battery out there and it's super cheap. Just needs an external power supply and that's pretty much it. You can either buy a power supply, or mod an ATX PC power supply. I had a PC power supply laying around so I used that. Super easy to mod and cheap.
 
The xl2 has some flaws. It almost requires the cap pack to control ripple. It also has a weak bec. Use an aftermarket one.

I don't have any specific batteries in mind, but make sure they are capable of 300 amps, preferable 350. Take a peek at what some of the 8s losi converts are using.

Traxxas and deans wont cut it. Ec5 at minimum. Castle greens are better. 8mm bullets are best but bullets scare me.

I love my power lab 6 and homemade server based power supplies. It may not seem like much, but the power lab series has 1 amp charges on the balance lead, as opposed to others 1/2 or 1/3. This helps A LOT as you get into multiple cell counts. icharger makes some awesome rigs too but im not as familiar with them.
 
Last edited by a moderator:
The amp draw will determine what connectors you can run. The 8mm bullets are nice and can handle a lot of current. The deans connectors will most likely get too hot. The high voltage escs are expensive. The cap bank is good insurance and can save your esc. The big motors with their huge draw can cause enough drop to fry the esc.

You would be better off with a pair of 8s in parallel than the 4s in series.

I have the I charger 4010 duo and just love it.
 
Thank you everyone for your input. So far I have the Castle ESC cappack, 8mm motor/ESC plugs and green high output battery/ESC connectors ordered. I scanned through the BL 5T link, I guess I should also get the Castle Pro BEC as well? Still would like more first hand lipo size and rating ideas.
 
You need as much as power as possible.

I run Turnigy packs. Only 65c and higher. You will puff you packs with less.

I run only parallel setups. If not you will get really short run times.
 
Too bad CC doesn't post the specs on their ESC's. We would be able to properly match a pack to them. Usually with the C rating, you want double what the ESC can draw. For example if you're running an 80A ESC, you want to run a battery that can supply at least 160A.

The formula to figure out how many amps the battery can supply is:

mAh x C / 1000 = A

So it would be:

5000mAh x 40C / 1000 = 200A
 
Got a pair of Turnigy 65c lipos and added the Castle green connectors. This is the most that I have ever spent on lipo.....EVER. Although I have yet to get a charger, I would like to get educated on the proper way to 'break in' and maintain these. I have always heard that you don't just buy, charge and go. Is there a process involved at this price range? Even a link to detailed steps.
 
A decent lipo charger makes it easy. Your esc should keep prevent you from over discharging.
 
I have also heard that no break in period is needed... but iv also seen with my own packs that the ir goes down on lipos (effectively increasing c) over the first few packs. Because of that I do not run my big lipos all out for the first few runs and only run them to about 3.7v. No idea if it helps but it makes me feel better.

For chargers, I love my powerlab. Others do great with the icharger series. Both are great chargers with the customer service to back it up.

For power supplies, two server supplies wired together will provide all the juice you need at very little cost.
 
My XL2 didn't come with an on/off switch. Power is applied by plugging & unplugging the batteries. I know several people who remove the switches from their ESC if it has one.
 
It's been about 5 years since I did anything RC. Back then I was 1/8 scale and using the Mamba Max which had a switch. I seem to remember for the initial startup you would plug in the batteries, squeeze and hold the throttle, turn on the switch and proceed to program your setup. Now without a switch, how is the initial startup done? The manual that came with my XL stills shows and guides you with a switch.
 
Castle switches are just an on/off tool. Hobbywing and similar use them for tuning, not just on/off.

in castles case, you set the throttle position by pulling the trigger and plugging in the batteries. The esc going into programming mode when it turns on and sees a specific trigger position. The switch makes this easier when using 2 hands, but had become a common short point in some of their older models. That is why many cut the thing out from the get go.
 
Here's a pic's of my conversion. It's not 100% yet.I still have to do a few things to it like a cap pack,dual servo's and a new body. I love the power but it's hard on the tires. With the punch control set at 40% it spins the tires on the pavement.

20140329_185740_resized.webp

20140329_185756_resized.webp

20140329_185806_resized.webp

20140329_185740_resized.webp

20140329_185756_resized.webp

20140329_185806_resized.webp

/monthly_2014_03/20140329_185740_resized.jpg.778bc7b911cee169d13694570bdabe59.jpg

/monthly_2014_03/20140329_185756_resized.jpg.359088eed131dea010ce50bf4e505b9c.jpg

/monthly_2014_03/20140329_185806_resized.jpg.087ccd584c647bff4522effd7fb8f642.jpg
 
Back
Top