imhotep

I'm getting back into RC and I find that many things have changed in the past several years. Where can I find a good, comprehensive guide to understanding the following.

- NiMh vs LiPo, care and conditioning of each, proper use, converting cars, etc

- Same as above for brushless motors, implications for ESCs, etc.

Thanks for your help!

niznai

The internet?

imhotep

I've googled for these topics but so far I've not found well-done guide. I was suprised to see that these forums don't have stickies to get nebies started actuallly, or maybe I just missed them.

imjonah

Not a complete answer to your question but this might help

Batterys LiPo NIMH http://www.rcgroups.com/batteries-and-chargers-129/

They are a mostly focused on RC Airplanes but by far the most knowledgeable, in depth discussion of batteries and chargers on the web.

EXEC Sum: Li-Pos have all but replaced NIMH in the last 2 years, primarily because they are lighter and unlike NIMH the don't seam to weaken with each successive charge also they tend to give out there full voltage over the full course of a race. The prefered way of charging Li-Pos is with a balance charger which essentially charges both cells (7.4 volt Li-Po = 2x 3.7volt cells. equally so both cells end up with the same volt. You can get a pretty sophisticated multi chemestry (NICad,Nimh,Li-po) computerized charger from Hong Kong for less than $50 or US branded equivalents in the under $75 price range. (check out the above URL for discussions of various models) ROAR and most organized race programs are going to want you to take precations like using a battery protected by a hard shell plastic case and to charge the battery inside a flame retardent {LipoSack}.

Brushless motors have also replaced brushed motors more or less, because they require little or no maintainence. You will need a brushless Electronic Speed Control. You can visit the various manufactures web sites and view some threads here. Pretty much it is matter of deciding which class 13.5, 17.5 etc they run locally that you want to run in. Its tough to go wrong with Novak, Tekin or Orion.

Chassis Just choose one of the competitive brands and pay your $400-500. Then find the thread for your model here on RCtech, read it from the start and then ask questions. Tough to go wrong with X-Ray T2 , Hot Bodies Cyclone. Dual belt have replaced single and shaft competitively.

The changeover to Lipo/brushless has caused some uncertainties about class definitions(what to replace mod,19t,stock with) they are sorting things out with lower weight minimums and different 'turns' of brushless.
Also foam tires indoors are fading in popularity in favor of rubber tires.

niznai

The reason you didn't find anything comprehensive is probably that there isn't one guide as such.

There is way too much information which is why I initially answered with a joke.

My suggestion is you go down to your local track or hobby shop, ask a few questions there and get back here see if you find a discussion about the batteries/chargers/motors/esc you have been told about. That way you can build a fairly good idea what you've missed in R/C over the last few years. Perhaps it is a good idea to decide if and what (class) you want to race and start from the car you want to buy. That will constrain somewhat your choice of motor/battery/etc.

Otherwise it would be easy for us to tell you what everybody is using, but this tends to transform such topics in a never ending dispute amongst us about which is better motor/esc/battery/etc and I am not sure it would help you.

About batteries, I would say things are the most simple as everything other than Lipo is either dead or not yet very widespread. Sure, if you have a particular application in mind that may change things, but if you want to go race cars, it is pretty easy. You need a hard case lipo. Which one it will depend largely of regulations where you want to race as well as car chassis (not all can accept any battery and some are easier persuaded to do it than others).

Nimh are only still used (as far as I know) in some european competitions and I don't think that's going to last much longer. They're a lot more demanding in terms of care and have lower life expectancy in racing conditions. To properly manage Nimh you need an individual discharger, you need to buy matched packs, etc. All these coupled with the relative little use they have these days make for a high price if you can still find someone who does sell them (matched packs I mean; 'normal' batteries are still available and rather cheap). You can easily buy a Lipo race pack for the same money.

imhotep

imjonah, thanks for the feedback and link. The limited amount of reading I'd previously done left me wondering how complete the LiPo revolution is, but it sounds like it's unanymously the way to go. I've got lots of catching up to do obviously.

I see lots of comments about converting to LiPo which made me think it was still so new that kit makers haven't started making vehicles that are engineered to accept a LiPo pack. What's the story on that?

Thanks agian.

adamge

iTrader: (1)

This site has some good info:
http://www.rctoys.com/pr/ (along the right side, check the motor, ESC, charger, balancer, and lipo categories)

niznai

A lot of cars on the market today have been designed when Lipos where still not competition approved so they were mainly aimed at Nimh packs. Some competitions still don't allow Lipos, but I think that will change in the future if not changed already. There are also a bunch of rather old cars people still race so that's another possibility to capitalise for a company making after market conversion kits.