This seems like a fairly basic thing but if you haven't ever done it before it can be a little confusing as to what the best approach is.  Unfortunately I didn't have an extra set of hands to help take photos so I won't be able to show the two-handed action which is at the heart of a good soldering job but I can at least show the tools needed, explain some technique and show the end result.  The example will be a deans connector soldered on to a lipo battery suitable for a 450-sized electric helicopter.  This can also be applied to RC cars, planes, transmitters and any custom connector for any application.

Anyone who owns a T-Rex 450 or 500 knows that one of the big downers is the short flights and long charge times.  I have a Thunder Power 610c charger which is capable of charging a 6 cell pack, however I only have 3 cell packs for my T-Rex 450.  I read a forum post somewhere where someone built a parallel balancer lead which let him charge 2 3s1p packs at the same time.  He had the right idea but the problem with charging them parallel like that is that the balancer can't see the true voltage of any one cell.  It can only see the combined average voltage of the 2 that are paralleled.  The only way to safely charge and balance 2 3s1p packs is to build a serial balance lead that combines the two packs into a proper 6s1p.  The charger can then see each individual cell and will charge up to 25.2v, balancing the cells to 4.2v each.

Blade strikes seem to be the number one enemy of the E-Flite Blade CX2 Helicopter. I have them all too often now when I'm flying my heli around. While alternatives exist that help reduce blade strikes, I am currently opting to just keep replacing the rotor blades of my CX2 as I break them. Here's how to quickly replace a rotor blade:

If you bang up your CX2 too many times, you may end up with a bent inner shaft. A good indicator is if the helicopter has vibration when throttled up and the blades are undamaged. Fortunately, E-Flite Helicopters are easy to work on and the inner shaft isn't too difficult to replace. I was able to take care of mine in about 20 minutes start to finish. Read on for a picture tutorial showing how to do it.

Like many people this year, I was fascinated by all of the new micro battery-powered RC helicopters showing up for christmas. The videos would show them performing precise acrobatic maneuvers, picking up little items, play-fighting in the air and just being a blast in general to fly. They looked easy to operate, quick to learn and they were relatively cheap. I've always been interested in RC Planes and Helicopters but it wasn't until recently that they've become affordable enough for the average person to buy.