As reported in my previous post, I needed to re-balance the rotor-blades. Again… Also, the glowplug needed a checkup.

The glowplug was easily fixed: some oil got between the alligator clip and the glow plug which caused some bad contact. After cleaning both the clip and the plug the glow heater was able to pump 4A through the circuit.

Rebalancing the blades was a bit more work…

I removed the balance-tape from the blade, cleaned all dirt and oil, and added the new balance tape.

This is the balance-result:


The edge where the bolt is balancing on is 1.35mm wide. The bolt is a tiny bit off center; depending on where the actual contact-point is located, the balance can be off between .225mm left and 1.125mm right (measured on the photo);

A little calculation tells me that this is equivalent to adding between at most .09g to the right tip (to compensate at most the .225mm left) and at most 0.45g at the left tip (to compensate at most the 1.125mm right offset). I think this is fairly good?

Next comes the Center-of-Gravity. I used the same edge to find the CoG spot; I verified the spot using an upside-down ballpoint pen (with its tip not extended):


(The pen has a tip-diameter of 3mm)

Both CoG’s are approximately 315mm from the center of the blade grip bolt. With the naked eye, I couldn’t tell the difference.

Now it’s up to the field again to test-run this new setup.