Need Advice on...

[bertberr]

...well, a few things actually. I want to get back into RC cars again after a 20 year break, partly because I really enjoyed building and driving my three cars back in the 80's (Cheetah, Frog & Hornet) but also because I think my little lad would enjoy playing with them too...or so I tell my wife (he's 2).

OK, so I want a 1/10th scale 2wd buggy for thrashing around the garden, up the road, over homemade jumps etc etc, but... with the proviso that it's a good enough base to make a few upgrades to should the bug really take hold. This rules out a re-released Frog/Hornet because lets face it they were hardly state of the art in the 80's, so I've narrowed it down to either an Ansmann Mad Rat or Tamiya Desert Gator. I know the Gator is a little more expensive even after you've splashed out for the ESC on the Rat, but they're pretty close (I've seen a Gator kit for £80 online).

Questions:
1. Mad Rat or Desert Gator - any first hand experiences?
2. Lipo or NiMh? Lipo worth the extra expense (battery & charger), remember I'm not planning on going racing...yet...???
3. I want to save a bit of cash by using my old Ko Propo radio gear, servo and receiver, but I'm unsure if they'd be compatible with an ESC equipped car? I've heard that I won't need the 4xbattery pack in the car as the 7.2v battery supplies both receiver & ESC - is this correct? If so will my old Ko Propo receiver be OK? I know I could get a new Acoms Techniplus for £35 or so, but if I can make use of the old radio gear I'd be happier, and its £35 towards the first upgrades...
4. Chargers - can I use my old tamiya branded trickle & 15min fast charger should I decide to go the NiMh route? Or will I need a new charger?

Thanks
BB

[Col]

I'll do my best...

Originally Posted by bertberr

Questions:
1. Mad Rat or Desert Gator - any first hand experiences? none, but I'd go for the mad rat.
2. Lipo or NiMh? Lipo worth the extra expense (battery & charger), remember I'm not planning on going racing...yet...??? lipo everyday - you charge, use, re-charge and forget, unlike nimh.
3. I want to save a bit of cash by using my old Ko Propo radio gear, servo and receiver, but I'm unsure if they'd be compatible with an ESC equipped car? I've heard that I won't need the 4xbattery pack in the car as the 7.2v battery supplies both receiver & ESC - is this correct? If so will my old Ko Propo receiver be OK? I know I could get a new Acoms Techniplus for £35 or so, but if I can make use of the old radio gear I'd be happier, and its £35 towards the first upgrades...no extra battery pack needed. Your old stuff should be fine.
4. Chargers - can I use my old tamiya branded trickle & 15min fast charger should I decide to go the NiMh route? Or will I need a new charger? You'll need a lipo specific charger (if you go lipo - can be picked up for around £30 new for a basic one). Most morn nimh cells will not like your old charger either...

Thanks
BB

If you're willing to splash a bit more cash there's a whole load of RTR cars available as well.
Hope that helps

[bertberr]

Col thanks for reply, am I right in thinking that a lipo has no 'memory', so it won't effect battery life if you charge it when not completely drained? Or is that the difference between NiMh & NiCd?

How does the receiver get its power exactly? On my old cars there was a plastic battery holder with 4xAA's that plugged in to the receiver alongside the two servo plugs. Is there now an extra wire that runs from the stick battery to the receiver???

I don't really want RTR as I enjoy building the kits, and I think it helps you to understand the buggy a bit better when you come to think about upgrades...

BTW, will I need a soldering iron for anything or it now all pre-soldered and / or plugs etc?

Cheers

[bodgit]

If your going to use lipo with your old esc then you will need a novak smart stop. Its cuts off power to prevent the battery voltage dropping below 6.2v.(2 cell) If a lipo drops below this then it can cause damage to the cells.

[Col]

Originally Posted by bertberr

Col thanks for reply, am I right in thinking that a lipo has no 'memory', so it won't effect battery life if you charge it when not completely drained? Or is that the difference between NiMh & NiCd?

How does the receiver get its power exactly? On my old cars there was a plastic battery holder with 4xAA's that plugged in to the receiver alongside the two servo plugs. Is there now an extra wire that runs from the stick battery to the receiver???

Lipo' are ace. No memory what so ever, so as long as they're around 70-80% charged when stored then they'll last for years with no problems.
Without having my car available to look at, the wiring goes a bit like this....:
esc plugs into batteries. A small 3 pin plug runs from the esc into the receiver which supply's power to the receiver (and the servo by another 3 pin plug) so no extra wires at all.

As bodgit mentioned as lipo safe is recomended to prevent the lipo from dropping below 6v as this is about the only thing that will ruin them. I never bothered with one when racing (5 min races) as they'll never go flat in that time, but with bashing I'd get one to be safe.

I'll find a pic of someones car to show wiring better than I am explaining...

[Col]

Here's a typical pic of saddle lipo (on the left) and brushless esc and motor (middle and top). The esc gets power (black and red wires) from lipo and the receiver (botttom right) spreads it elsewhere via the small red, black and white leads.



This pic is stolen from "trap121" in the durango thread...

[RogerM]

Be careful if using old recievers as they sometimes struggle to deal with the power draw of modern servos wether using their inbuilt BEC or not as the circuit board tracks are a little small / high resistance.