Brushless Tips

[GTodd]

Hi everyone, I just began to build my DS. She is going to get a Novak Brushless and numerous Nimrod upgrades. My question is what do I have to know about brushless?

I have a specific LIPO charger, is it true that I can only slow charge LIPO batteries?

What is the typical run time for a 13.5 Novak brushless on 2 LIPO cells?

Can I mix and match NICAD and LIPO batteries with speed controler, or will I have to reset the controller for NICAD or LIPO batteries?

Anything else you brushless experts would like to add is welcomed, thanks!!!!

[94eg!]

1 - Hi everyone, I just began to build my DS. She is going to get a Novak Brushless and numerous Nimrod upgrades. My question is what do I have to know about brushless?

2 - I have a specific LIPO charger, is it true that I can only slow charge LIPO batteries?

3 - What is the typical run time for a 13.5 Novak brushless on 2 LIPO cells?

4 - Can I mix and match NICAD and LIPO batteries with speed controler, or will I have to reset the controller for NICAD or LIPO batteries?

5 - Anything else you brushless experts would like to add is welcomed, thanks!!!!

1 - The only thing special about brushless is that you must not overheat the motor (never over 160*f). The only way to determine proper gearing for racing is w/ an infrared thermometer. For bashing, simply make sure it stays cool to the touch.

2 - For guaranteed safety and long life, Lipo should be charged at 1C (1 times capacity). Example: 4000mah lipo should be charged at 4000mah (or 4amps). That means a fully discharged lipo will take a little over an hour to charge. Just make darn sure your using the Lipo profile or you can/will have a chemical fire on your hands.

3 - Typical run-time depends on the milliamp rating of the battery being used. Of course a lipo battery will run much longer than a nickle battery of the same capacity since they have much lower internal resistance (less energy being wasted as heat). I'm sure w/ a 5000mah lipo you could easily get a half-hour of bashing about in a buggy like the DS.

4 - You don't have to reset the ESC for lipo and nimh. You can leave the low-voltage lipo safety cutoff on all the time. Be aware that nickle batteries suck in comparison so voltage will drop quicker (especially under load) and you may hit the cutoff much sooner. If you are having problems w/ nickle batteries cutting out, you may have to disable the Lipo cutoff. Just be sure to switch it back on when switching back to lipo. If you plan on running lipo in the car, it's best to stick w/ lipo. High power brushless runs like **** on nimh/nicad.

5 - Make sure the lipo is rated w/ enough output to support your motor. A 20C 2400mah lipo can only put out 48amps continuously without being damaged (20 times capacity). Many motors are capable pulling quite a bit more. For low turn motors, go with a higher capacity and/or C rating. A decent lipo would be a 4000mah 35C pack. This can lay down 140amps continuous current without giving up the farm. The higher C rate and mah, the more cycles you'll get out of the pack (cause it is not working as hard).

In addition it will be mandatory to run a good battery connector like Deans or Traxxars TRX plug. The crappy tamiya connectors of the old days will melt together w/ brushless/lipo current flow.

BTW: The DS is a very old car and doesn't have much room for your batteries. I would recommend a lipo that has the built in 4mm bullet tubes. Also, you probably won't be able to fit anything greater than a 4000mah pack. I just ran a Yeah Racing 3200mah 25C stick-type pack in mine last weekend. I had to dremel out the battery tub so the super fat wires and balance tap could exit straight out the front end of the battery compartment towards the servo. Lipos aren't exactly the same size as a nicad stick pack.

Bullet plugs exit the top corners easily. simply solder the 4mm bullets to the ESC wires. Don't mix up polarity...

To fit this pack, I had to dremel out a good size notch in the battery tub of the DS for these huge wires and balance plug:

[GTodd]

1 - The only thing special about brushless is that you must not overheat the motor (never over 160*f). The only way to determine proper gearing for racing is w/ an infrared thermometer. For bashing, simply make sure it stays cool to the touch.

2 - For guaranteed safety and long life, Lipo should be charged at 1C (1 times capacity). Example: 4000mah lipo should be charged at 4000mah (or 4amps). That means a fully discharged lipo will take a little over an hour to charge. Just make darn sure your using the Lipo profile or you can/will have a chemical fire on your hands.

3 - Typical run-time depends on the milliamp rating of the battery being used. Of course a lipo battery will run much longer than a nickle battery of the same capacity since they have much lower internal resistance (less energy being wasted as heat). I'm sure w/ a 5000mah lipo you could easily get a half-hour of bashing about in a buggy like the DS.

4 - You don't have to reset the ESC for lipo and nimh. You can leave the low-voltage lipo safety cutoff on all the time. Be aware that nickle batteries suck in comparison so voltage will drop quicker (especially under load) and you may hit the cutoff much sooner. If you are having problems w/ nickle batteries cutting out, you may have to disable the Lipo cutoff. Just be sure to switch it back on when switching back to lipo. If you plan on running lipo in the car, it's best to stick w/ lipo. High power brushless runs like **** on nimh/nicad.

5 - Make sure the lipo is rated w/ enough output to support your motor. A 20C 2400mah lipo can only put out 48amps continuously without being damaged (20 times capacity). Many motors are capable pulling quite a bit more. For low turn motors, go with a higher capacity and/or C rating. A decent lipo would be a 4000mah 35C pack. This can lay down 140amps continuous current without giving up the farm. The higher C rate and mah, the more cycles you'll get out of the pack (cause it is not working as hard).

In addition it will be mandatory to run a good battery connector like Deans or Traxxars TRX plug. The crappy tamiya connectors of the old days will melt together w/ brushless/lipo current flow.

BTW: The DS is a very old car and doesn't have much room for your batteries. I would recommend a lipo that has the built in 4mm bullet tubes. Also, you probably won't be able to fit anything greater than a 4000mah pack. I just ran a Yeah Racing 3200mah 25C stick-type pack in mine last weekend. I had to dremel out the battery tub so the super fat wires and balance tap could exit straight out the front end of the battery compartment towards the servo. Lipos aren't exactly the same size as a nicad stick pack.

Bullet plugs exit the top corners easily. simply solder the 4mm bullets to the ESC wires. Don't mix up polarity...

To fit this pack, I had to dremel out a good size notch in the battery tub of the DS for these huge wires and balance plug:

Wow great tips, thanks!!! Well I have a 5000 with a 30c burst rate, BUT it does not fit so I am going to have to figure out how to fit it. Im thinking that one of my spare Super Astute or TF battery box ends will work.

[Singapore_959]

Sorry I have no photos to hand, but before I changed my chassis I did the same thing as ORB suggests - cutting. I cut out a large square from the front of the battery box to let the wires out and make it easy to slide big packs in.

Also you do not need the huge metal plate on the end of the batterybox / in front of and under the shock tower. It was only designed and put there to hold the CPR unit if you were using it. Remove it, save weight, and make it easier to slide in larger battery packs.

The aftermarket chassis like nimrod and the old TRF decks have no problem fitting larger packs. Lipos are great. I tried 4500 NIMH packs a couple of times but they were just too heavy to be usefull. I usu use 3300 or 3900 packs when using NIMH. Lipo no such issues. Infact have to use weights sometimes.