Radio Control: Helicopters

RADIO CONTROL HELICOPTERS BLADE BALANCING TECHNIQUES Now middle summer should out flying enjoying helicopter best ways improve helicopters performance reduce vibration making sure everything balance sources vibration biggest main rotor system specifically main rotor blades can find better way balance will reduce helicopters vibration will help model fly better good time discuss basic principles balance techniques since havent done recently Blade balancing theory simple three criteria depicted Figure 1 1 The blades must balance balancer 2 The spanwise Centers Gravity CG must same 3 blade weights must same two above characteristics present third automatic reality has developed two basic blade balancing techniques matches CGs blade other uses accurate scale match blades weights both techniques blades brought balance using something similar Revolution Blade Balancer High Point difficult costly timeconsuming technique has matching blades weights has also accurate technique because weight can determined 1/jo gram desired Matching blade CGs has guaranteed specified accuracyuntil recently Laurel Koll has designed Koll Rotor Pro balancer manufactured sold Miniature Aircraft 3743 Silver Star Rd Orlando FL 32808 invention important because first balancer match apparent spanwise CGs number rotor blades say apparent CGs because although Koll Rotor Pro can identify exact CG point has adjustable weight blade-holding arm affect apparent CG location Dont worryif apparent CGs matched actual CGs fine point bring up accuracy reporting Koll Rotor Pro will also match apparent chordwise CGs something else no other balancer has able accurately As weight added subtracted blade match spanwise CGs blades can also matched chordwise CGsthis measurement seriously considered before became way measure accurately Rotor Pro beneficial advancement blade balancing since High Point introduced years ago Rotor Pro can balance rotor blade sizes including 60- 30-size main rotor blades tail rotor blades Three- four-millimeter bolts provided mounting blades balancer check overall balance would High Point blade balancer Rotor Pro also has attachment hold propellers other objects need balanced Although detailed instructions come balancer basic idea make lighter blade master match other blade CG can easily done making new set weighted blades first using balancer High Point Revolution Blade Balancer determine blade weighs less ensures no extra weight other what required fill slot provided will needed However blades will receive additional weight such balancing new set fiberglass blades rebalancing set already using use heavy blade master ensures weight added light blade weight can positioned match spanwise chordwise CGs Once master blade has determined weight can added other blade bring overall balance match spanwise CGs technique use lock blade-holding arm position mark apparent CG master blade balance Rotor Pro place other blade Rotor Pro add weight needed obtain same spanwise CG weight can also added closer leading trailing edge correct chordwise CG use High Point Revolution Blade Balancer check overall balance adding weight true CG light blade until brought balance negative points Rotor Pro 1 needs rubber feet keep slipping table bought pack stick-on feet Radio Shack less $1 2 balancing bubble may need calibratedthe balancer should level bubble centered easy check Place long straightedge balancer use adjustable weight center bubble straightedge should horizontal ends equal above level table straightedge isnt level use pair pliers bend bubble-holder slightly check again Koll Rotor Pro inexpensive alternative purchasing own would have club purchase club members use would keep cost down user still provide everyone ability balance blades became believer Rotor Pro after checking set blades thought balanced flying quite off slightly spanwise chordwise CG just few dollars best technique balance rotor blades use Koll Balancer gram scale accurately measure blade weights Remember match CGs Koll balancer weight gram scale blades must balance High Point may able find good used gram scale pawn shop can place want ad local newspaper Although triple-beam scales very accurate difficult time consuming use recommend digital electronic scale think will see big pleasant difference helicopters performance Helicopter Pen Pal received letter Vidal Kaupelis Vitniaus 26-22 Siauliai Lithuania Europe looking pen pal get acquainted discuss aspects model helicopters Vidal aircraft engineering piloting student Vilnius Aviation University works mini factory air models st1997 107 CUl-- CU2 4/ Weight 1Weight 2 Figure 1