KSJ 528 Blade Balancer - from HeliProz
We think this is the best blade balancer in this price range. Unlike the simple "balance beam" units, the KSJ lets you check the spanwise balance easily and accurately as well as balancing one blade against the other. The Koll Rotor Pro (which we also stock) adds the ability to check chordwise CG, - it's priced at more than twice as much as the KSJ.

The above photo shows the KSJ 528 balancer assembled. The tray has weights that allow you to adjust it to be in balance without the blades installed, and is supported by ball bearings on each side. Put the balancer on a level surface, balance the tray with the blade posts to fit your blades and you're ready to go. (It comes with 2, 3 and 4-mm posts for most main or tail blades). Pretty obvious how to use this - the pointer shows you if the blades are in balance with each other. Add weight to the blade that the pointer doesn't lean towards. (Where you add weight depends on the spanwise balance point - see below).

To check the spanwise balance point you remove the blade posts and put the blade on the balancing tray as shown above. A groove molded into the tray will show you exactly where the balance point is. Mark the blade where the groove is and check the other blade. You want the spanwise balance point to be within 1/16" between the two blades. (Your balance point mark will move TOWARDS whichever end of the blade you add weight to).

Using the KSJ 528 Balancer

Before you add any weight anywhere, check BOTH the spanwise balance and the blade-to-blade balance. There are only four possible outcomes you can find:

1. Both blades balance and have spanwise balance points within 1/16". In this case you are done. (and very lucky or bought very good blades).

2. The spanwise Balance is fine, but one blade is heavier. In this case you add weight (tracking tape or whatever you prefer) to the light blade, PUTTING THE WEIGHT ON the spanwise balance point of the lighter blade until the blades balance.

3. The blades balance with each other but the spanwise balance is off between the blades. In this case you will add EXACTLY the same amount of weight to EACH blade. Line up the blades and note which way the spanwise balance marks have to move to line up with each other, and put a test-piece of tape on one blade on the end that the mark on that blade needs to move towards (to match the mark on the other blade). Put enough tape on to move the mark HALF of the distance needed. Now (to keep the blade-to-blade balance) put exactly the same amount of tape on the OTHER end of the OTHER blade. NOTE - start by adding weight on the blade that need weight on the ROOT end. Add the tape as near the root as possible before the blade tapers. Now measure from the inner edge of that tape to the spot where you need the balance point to MOVE to. On the other blade, measure from that same final balance point the same distance towards the tip and MARK that spot, that's where the inner edge of the tape needs to be on that blade.

4. Both the spanwise balance AND the blade balance is off. (Not exactly rare). Okay. Start by adding weight to the lighter blade ON THE END (see above) that the balance point needs to END UP at. (Halfway between the two original spanwsie balance point marks). You'll need to keep checking the spanwsie balance as you go. If you have reached perfect spanwise balance BEFORE the light blade has enough weight on it, put the rest of the weight ON the spanwsie balance point until the blades balance with each other. If you reach balance between the blades before the spanwise balance is okay, proceed as in #3 above until spanwise balance is reached.

 

 
HeliNews
HeliProz ONLINE catalog
Products & Reviews
Beginners Advice
Flying R/C Helis
NEW PRODUCTS
About Our Online Catalog
 E-MAIL: sales@heliproz.com