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Guide to Dynamic Balancing V1.09                                                                                                           
WWW.RPXTECH.COM 

 

 
Balance / Analysis 

 

Clock the Prop and Change Weight 

 

 

Confirm that the ignitions are off and mixture is full lean. Rotate the propeller 
carefully until the small light at the back of the optical pickup comes on. This 
is the 0° position relative to the accelerometer. The angle indicated by the 
DynaVibe is the angle where the prop assembly is heavy.  

The angle is measured from the zero position of the accelerometer to the 
indicated angle in the direction of propeller rotation.
  

When the heavy point is identified, remove weight from this point. If there is 
no weight to remove from the heavy location, add weight on the opposite side 
of the propeller (indicated angle +/-180°). 

For instance, if the system is displaying 0.25IPS @ 90°, this is the position of 
excess weight.  If there are no extra washers to remove from the spinner, then 
weight must be added to the opposite side (270°, 90°+180°).  A typical O-320 
installation with fixed pitch prop and spinner may require two to four AN970 
washers to correct this type of vibration.  

Every installation is different due to the weight of the engine, propeller, 
spinner, etc.  Therefore, adding weight should be done in small increments 
and by making notes on the datasheet, the step-by-step correction gives you an 
indication of future changes.  

 

A good starting point is 50 grams / IPS

 

 

CAUTION:  

Verify ignition and fuel are off 

prior to moving propeller 

 

Summary of Contents for DynaVibe Classic

Page 1: ...DynaVibe Classic User Manual Version 1 09 Aug 2015 WWW RPXTECH COM...

Page 2: ......

Page 3: ...llation of Equipment 8 Remove Cowling 8 Mount the Accelerometer and Optical Pickup 8 Mount Reflective Tape on the Propeller 9 Using the DynaVibe 12 Attach the DynaVibe 12 Start Your Engine 13 Averagin...

Page 4: ...re please use extreme caution Be very careful with cables and components especially on pusher type aircraft ALWAYS confirm the ignition is off before rotating the propeller Areas of this manual will h...

Page 5: ...on causes accelerated wear and fatigue on equipment and passengers The negative effects of vibration can be reduced by dynamically balancing the aircraft s rotating assembly balancing the crank prop e...

Page 6: ...ine Applicable procedure For aircraft or propeller manufacturers that provide procedures for dynamic balancing propeller balancing is not considered a major airframe alteration When approved aircraft...

Page 7: ...quired There are instances where spinners have been installed in such a manner as to allow the front of the spinner to move relative to the propeller If the spinner structure has any flexibility it wi...

Page 8: ...lugs to allow the engine to rotate freely If one blade is positioned differently from another this indicates that either the blade is bent or the installation is unacceptable Again a dynamic balancer...

Page 9: ...y static balance weights Equipment Performance and Calibration Equipment used on certified aircraft must be inspected and calibrated The DynaVibe is available with National Institute of Standards and...

Page 10: ...n and fuel are off prior to moving propeller CAUTION Rotate the propeller slowly to confirm clearance of all components When you add weight confirm that you have not introduced any clearance issues Co...

Page 11: ...the engine The optical pickup should be mounted approximately six inches behind the back of the propeller The accelerometer should be mounted as far forward as possible for maximum sensitivity A commo...

Page 12: ...ar that the optical sensor cannot obtain a reading from the tape Mount Reflective Tape on the Propeller By placing the small piece of reflective tape provided in the kit on only one propeller that pro...

Page 13: ...the center of the tape The photo pickup is configured to pulse a small light on the back of the photo pickup When the photo pickup is correctly illuminating the reflective tape the back of the photo...

Page 14: ...uired would be 1 9 inches Tape Length Required RPM 6 from hub center 12 from hub center 24 from hub center 500 0 2 0 4 0 8 1000 0 4 0 8 1 6 1500 0 6 1 2 2 3 2000 0 8 1 6 3 1 2500 1 1 9 3 8 3000 1 2 2...

Page 15: ...rometer and optical pickup cables from the engine compartment The cables are keyed so look closely at the connectors before plugging them into the DynaVibe Back of DynaVibe CAUTION Verify that the are...

Page 16: ...Vibe RPM reading is accurate relative to the displayed RPM If the RPM is erratic or incorrect this may indicate that the optical sensor is not properly in line with the reflective tape The DynaVibe wi...

Page 17: ...engine to idle Allow the engine to run at the lower RPM for a short period of time to cool Limitations Correction weights should not be attached to a damaged or cracked spinner or spinner backplate Tr...

Page 18: ...ght to remove from the heavy location add weight on the opposite side of the propeller indicated angle 180 For instance if the system is displaying 0 25IPS 90 this is the position of excess weight If...

Page 19: ...likely that the readout would be 0 17IPS 90 This gives a good indication that the single washer corrected approximately 0 07IPS of vibration While this would imply that one could quickly add two addi...

Page 20: ...er 3 16 Light washer AN960 10 0 9 Flat Washer 3 16 washer AN970 3 3 9 Flat Washer 3 16 washer AN365 1032A 2 2 Elastic Stop Nut 10 32 nut AN525 10R6 2 1 Washer Head Screw 10 32 x 3 8 screw AN525 10R7 2...

Page 21: ...avoid corrosion under the tape Use as little tape as possible i e 1 inch strip and mount the tape inboard toward that hub so the balance is not affected by removing the mass Accelerometer Mounting Th...

Page 22: ...s ambiguity is eliminated by simply measuring in the direction of prop rotation The engine RPM must be stable for a valid vibration reading Hold RPM as stable as possible when balancing The engine sho...

Page 23: ...mperatures If cylinder temperatures are drastically different it may indicate bad spark plug wires fowled plugs intake leaks poor fuel distribution etc Verify that the spinner is balanced by placing i...

Page 24: ...21 Guide to Dynamic Balancing V1 09 WWW RPXTECH COM We maintain troubleshooting and balancing tips on our website so they can be continually updated Check www rpxtech com dv tips for the latest tips...

Page 25: ...ack 4 cowling 8 20 cracking 20 cylinder 20 Documentation 17 DynaVibe 6 12 13 14 15 FAA 3 4 5 Limitations 14 NIST 6 Pickup 8 Pitch 4 pre balance inspection 3 6 Propeller 3 4 9 14 Reflective Tape 9 serv...

Page 26: ...To download and print this chart please visit WWW RPXTECH COM CHART...

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Page 28: ...WWW RPXTECH COM...

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