An essential part of building and setting up every heli is to balance the main and tail blades both dynamically and statically. Although it's not difficult to do, it does take a little time to do it correctly. To get the best results, the blades must be balancing in motion such as a tire is spun up and weight added to balance the shake. This could be done on a heli as well by trail and error but the explained method will get you very close if not almost perfect balance. If done correctly, it should eliminate almost all vibrations. Below are the basic items that you will need. If a triangle ruler is not available, a razor blade glued to a wood block would work just as well. A decent highpoint balance such as the Dubro is a must. Two razor blades glued to a wood block would work to get the job done. Trim tape to be used for tracking and clear tape for adding weight and a marker for marking the CG.

Start by trying to get the CG on both blades the same, place each blade on the ruler or razor blade until you get them to balance, then mark the spot with the marker on each blade. Take extra care to make sure the blades are perpendicular to the ruler or razor blade. Now do the same for the other blade and compare the two.

Line both blades next to each other side by side matching the roots and tips. The one with the CG closest to the root gets moved to the tip so that means we add tape to the tip to move it out. The same tape can double as the tracking tape. The CG of both blades is brought to balance by adding the black trim tape to the light blade. The tape also aids in tracking. This completes the Dynamic balancing part of the blades, so now when the blades spin, the CGs will be at the same point. The CG marks are left on the blades, this is where we add the weight when final balancing the whole head assembly.

The static balancing can be done by either using a highpoint balancer like the Dubro or the two blades can be bolted together and hung by a string, the balancer is much more precise. First we balance the flybar and paddles assembly and then add the blades. The whole main shaft assembly can be used to balance both the paddles and blades as shown. It helps to keep a spare main shaft to aid in balancing, so that you don't have to take it off the heli every time. Here you can see an unbalanced flybar and paddle assembly. Tape is added to the lighter paddle until the set is balanced. Clear tape can be added under the paddle to hide it.

The flybar assembly after adding tape to the lighter paddle to balance them. Add the blades and follow the same steps to balance them, except this time we add the weight on the CG marks. Add tape to the lighter blade until they balance. Here the blades are balanced both statically and dynamically. This should eliminate most if not all of the vibrations. The assembly is now ready for flight.

The same procedure is used to balance the tail blade, the whole tail shaft assembly can be used to balance the blade or blades in helis such as the hornet.
Here we see an out of balance tail rotor. Balance by adding tape to the lighter blade until they balance. Now the tail should also be in balance. A well-balanced heli will not only perform much better, but it will suffer less wear from the vibrations as well increased flight times!