PDA

View Full Version : Best Brushed Setup



WeatherB
11-03-2005, 04:13 PM
Hey guys,
After getting fed up with the lack of torque and cogging on my Mamba setup I decided to switch back to the brushed configuration.

I wanted to use my existing 3-cell Lithium cells so I tried these:

Setup #1:
Futaba MC230CR
Apogee 1660 3-cell Lithium
Graupner 4.8 volt (stock pinion)

I ran this indoors with good results and okay temps (150 motor, 120 ESC, 90 batteries). The car was very fast and powerful. I then installed the body and took the car to my garden, after about 5 minutes of running I noticed that car had no power. I checked the temps again and noticed the motor was 250F. I ran it a couple more times and then the motor died.

Setup #2:
Futaba MC230CR
Apogee 1660 3-cell Lithium
Stock motor (16 tooth pinion)

I had to install a 16 tooth pinion since the stock pinion wouldn't come off the Graupner motor. Once again I ran the car indoors but this time with the body. The car once again ran good and strong. Temps were good too, after about 10 minutes of hard running the motor was 170, 110 esc, 83 batteries. I had yet to try it outside but I think I should purchase a stock pinion before taking it to the garden. I think the 16tooth in overkill.

I am very impressed with these Lithium cells, I've never finished a battery charge yet. I played around for 5 minutes yesterday and recharged the pack. The charger only put in 110mah. THAT'S CRAZY! That equals to about an hour of run time. :eek:

DrVonHoSS
11-03-2005, 10:34 PM
Hey guys,
After getting fed up with the lack of torque and cogging on my Mamba setup I decided to switch back to the brushed configuration.

I wanted to use my existing 3-cell Lithium cells so I tried these:

Setup #1:
Futaba MC230CR
Apogee 1660 3-cell Lithium
Graupner 4.8 volt (stock pinion)

I ran this indoors with good results and okay temps (150 motor, 120 ESC, 90 batteries). The car was very fast and powerful. I then installed the body and took the car to my garden, after about 5 minutes of running I noticed that car had no power. I checked the temps again and noticed the motor was 250F. I ran it a couple more times and then the motor died.

Setup #2:
Futaba MC230CR
Apogee 1660 3-cell Lithium
Stock motor (16 tooth pinion)

I had to install a 16 tooth pinion since the stock pinion wouldn't come off the Graupner motor. Once again I ran the car indoors but this time with the body. The car once again ran good and strong. Temps were good too, after about 10 minutes of hard running the motor was 170, 110 esc, 83 batteries. I had yet to try it outside but I think I should purchase a stock pinion before taking it to the garden. I think the 16tooth in overkill.

I am very impressed with these Lithium cells, I've never finished a battery charge yet. I played around for 5 minutes yesterday and recharged the pack. The charger only put in 110mah. THAT'S CRAZY! That equals to about an hour of run time. :eek:


Did you update your Mamba ESC software with the Mamba Link? As soon as I did that ALL cogging went away.

If you run a Graupner 4.8 volt on a 3 cell lipo make sure you have a fire extinguisher handy.

An 1100 mAh pack will take 10 hours at 110mAh to charge.. assuming the battery is totally dead.

mat3833
11-03-2005, 11:32 PM
id try the graupner 6.0 volt. or just get an AON motor for your mamba 25 ESC, then sell the motor on ebay or somewhere. oh and what lithium cells are you using? what C and capacity? the cells could be you cogging problems source.

Matt

mat3833
11-03-2005, 11:35 PM
oh if you didnt kno:

What does the "C" mean in 10C, 20C etc ?
we use the designation 10C etc to mean how much a cell or pack can discharge in amps. C always equals the capacity of a cell or pack. For example. Let use a PQ31003S pack rated for 12C. In this case C=3100mah. the number before the "C" is the multiplier. so 12 x 3100 = 37200mah. to get amps we simply divide by 1000. 37200/1000 = 37.2 amps. 1000mah = 1amp.

So for the above pack (PQ31003S) rated @ 12c we now know the max discharge rating is 37.2 amps.

Another example: a 20C 1800mah 3S pack. What is its max rating? 20 x 1800 = 36000. 36000mah = 36000/1000 = 36amps. So the 1800 3s pack @ 20c has a max rating of 36amps.

so when ever you see a C rating take the number before the letter "C" and multiply the packs capacity by it. That is it. To get amps from your new number simply divide it by 1000mah.

hope this helps.

Matt

WeatherB
11-04-2005, 01:25 PM
LOL, who slow charges batteries anymore? 1C is the way to go.

I was told that my Mamba already had the newest firmware since the firmware came out a long time ago and my hobbyshop just got these in stock.

I am using two Apogee 830mah 3-cell packs in parallel. Each pack is 10.5C so in parallel it should be 21C. I doubt the cells are the problem. The Mini Inferno is just too heavy for the Mamba motors. Based on your calculations: 21 * 830mah = 17430mah / 1000 = 17.43amp dischange (continuouse). I believe the cells can peak to 42C (34.8amps)

As for getting the AON, I don't want to sink any more money into the Mini Inferno unless I am 1000% sure it will solve the problem. It's running just fine with my brushed setup right now.

EphiDelt490
11-04-2005, 02:21 PM
Ask Kortz if the Half 8 is too heavy for the Mamba motors ;)... Or just watch the video from the Pottbelly race and you can see a Mamba 5400 wrecking shop. Mine runs great with the 6800 in it, just need to pick up some LiPo batteries to get it really moving.

WeatherB
11-04-2005, 04:20 PM
That's weird? You don't have any cogging or torque problems? Mine runs fine on pavement or somewhere flat but once on the track you gotta give it a rolling start otherwise it'll cogggg like no tomorrow.

mat3833
11-04-2005, 05:38 PM
my mamba works great(5400) i plan to get the 6800 later and install my cooling fan. i have some cogging at the end of a pack but it is like an early warning system.

Matt

bermbuster
11-04-2005, 05:55 PM
my son ran a mamba25 esc with a 5400..... intellect1200s(8) and he had no problems......

WeatherB
11-05-2005, 02:36 PM
That's really weird... When I say cogging I mean that if you try to accelerate from a dead stop the car has problems going. You need to start moving really slowly (takes a lot of throttle control).

Regardless, I took my H8 on the track today and had no problems with my "best brushed" setup. I ran for about 20 minutes and used up 608mah from the pack. Motor temp was 131F. I think I should purchase a 14 tooth pinion for a little extra speed though.

JuJuB
11-06-2005, 10:31 PM
Offtop:
Where can I get that 480 BB motor from for how much? I'm planning on doin the conversion to my chasis to fit it on there (even though I've been saying that for 2 months now :D ). I hear that a 480 motor gives more power/speed. I'm gonna run it w/ an 8-cell pack.

snoopyspaz
11-07-2005, 06:54 PM
Offtop:
Where can I get that 480 BB motor from for how much? I'm planning on doin the conversion to my chasis to fit it on there (even though I've been saying that for 2 months now :D ). I hear that a 480 motor gives more power/speed. I'm gonna run it w/ an 8-cell pack.

www.hobby-lobby.com has them, do a search on graupner motors. good prices too :)

Peter

Ronny
11-13-2005, 12:40 AM
LOL, who slow charges batteries anymore? 1C is the way to go.

I was told that my Mamba already had the newest firmware since the firmware came out a long time ago and my hobbyshop just got these in stock.

I am using two Apogee 830mah 3-cell packs in parallel. Each pack is 10.5C so in parallel it should be 21C. I doubt the cells are the problem. The Mini Inferno is just too heavy for the Mamba motors. Based on your calculations: 21 * 830mah = 17430mah / 1000 = 17.43amp dischange (continuouse). I believe the cells can peak to 42C (34.8amps)

As for getting the AON, I don't want to sink any more money into the Mini Inferno unless I am 1000% sure it will solve the problem. It's running just fine with my brushed setup right now.

The AON 4900 with a Mamba 25 w/new update +those lipo's will NOT cogg!
This I promise you 1 million% brother ;)

Ronny