Turbinator
Heliman
Location: Nanticoke, PA
| Use Koll Balancer on allI would use a Koll balancer and make all 5 weight teh same and also CG the same. Just because they are close in weight does not mean they will balance one set to another becasue they may not weigh the same in the same places. Static balance and dynamic balance when spinning can be drastically different causing vibration in a 5 blade config, you would be OK in an even # config but not in a odd # config. What I have done is use small finishing nails drilled and glued chord wise put in on the leading edge toward the trailing edge of the blade at the CG point, tip, or root depending on what the blade needs to both weigh the same and balance the same which using the Koll Balancer coupled with a good gram scale makes possible with minimal effort. I use like 3/4 to 1" long small finishing nails or brads depending on teh chord of the blade, trying to keep teh weight mostly on the leading edge of the blade. If you really want to get perfect you can also try to balance them chord wise with the Koll which helps them all lead/lag the same in flight, again puttting teh weight were needed more to the leading edge or trailing edge depending on what is seen on the Koll and what the blades are made out of. Hollow CF ones being with foam core use a sharpe drill bit and a foam compatible glue, fiberglass use epoxy or ca, same with wood. When you have a set that is close to perfect they sing and run glass smooth. I also check the run out of the main shaft and also put the head on and check were each blade bolt is running with a dial indicator, some heads are horrible making even a perfect set of blades vibrate others are bang on within .001" and are ruined by porrly balanced blades, good balance saves bearings, airframes, servos, etc, and mostly your nerves as there is nothing like a glass smooth scale ship. |
