How to - Simple propeller balancing

by eluminerRC | July 5, 2013 | (18) Posted in How To

This is another how-to video related to my quadcopter build series. This time you will learn how to do one of the most important things in multirotor world - propeller balancing.

Due to the fact that multirotors have 3, 4, 6 or even 8 propellers, vibrations are number one problem. Gyros and accelerometers that flight controllers rely on are very sensitive to vibrations. If you are doing FPV or AP, vibrations are big no no as well. Vibrations can also cause structural failures. Balanced propellers, on the other hand (even motors for that matter), are key to success. Vibration free craft will fly better and longer.

Be aware that perfect balance it's not achievable. For near perfect balancing you will need better tools such as magnetic balancers etc. Also, balancing is not something you can't do in a couple of minutes. It requires time and patience. However, any balancing is better than non. So this simple method is way better than not do anything.

Also, don't think that expensive Groupners are perfectly balanced. In fact, there is no way that any manufacturer can produce perfectly balanced prop. Every propeller needs to be balanced, so learn how to do it.


1. Make sure that you are on the flat and level surface and that your "cups" are exactly the same hight. Balancer must be horizontal!


1. When sanding heavy blade, make sure that you don't sand too much. Do it slowly and check balance every once in a while. If you sand to much you will need to sand the other blade and that is not good. You will remove unnecessary amount of material.
2. In stead of sanding heavy blade, you can add thin CA on the light blade. That way the blade will be heavier, but you wont mess with structural integrity of the blade as you do when you sand it. Also, you can add tape to the light blade, but it usually flies of after a while and you have to start again (not recommended).
3. In stead of adding thick CA to the light side of the hub, you could sand heavy side. However, this is not recommended because you will usually have to remove large amount of material which can make the prop weaker. So, stick with adding CA to the light side only. Also, most of the time hubs are so off balance that you can't remove enough material at all.
4. Don't sand leading or trailing edge of the blade because you could disturb the air flow.

You need:

Propellers (for a quad you need 2x CW and 2x CCW)

8045 SF propellers and 8045R SF propellers

Simple prop balancer

Thick CA glue

180-220 grit sandpaper and two objects that are the same height (cups)


Enjoy RC as much as I do! :)


Mirabile Visu on July 5, 2013
Very useful, thank you. I've learned a lot from your videos, keep it up!
Log In to reply
eluminerRC on July 5, 2013
I will! Thanks! ;)
Log In to reply
mkoutnik on July 8, 2013
Nicely done! Thank you.
Log In to reply
RoyBro on July 5, 2013
I just went through a batch of Gemfan 9x4.7 props and they are all hub heavy. I mean VERY hub heavy. Interestingly enough the blades were nearly all balanced. I only had to adjust one or two prop blades. On one particular prop, I nearly had to add a third blade in CA before it balanced.
I wonder if they make lead impregnated CA for balancing purposes. Well I don't actually wonder, but they should.
Log In to reply
eluminerRC on July 5, 2013
Totally agree with you. Hubs on all GF props (not only 9x4.7) are way off. I was thinking about putting some small weight (metal) inside the glue because sometimes I just can balance the hub with reasonable amount of glue. That's where more expensive props come into play. Not that they are perfectly balanced, but at least you can balance them easily.
Log In to reply
Cyberdactyl on July 10, 2013
Me too Roy. I've had GWS props with insanely imbalanced hubs. It's crazy, because from the ...appearance... of the hub, you ask yourself where the hell is that extra mass. I've had to put around a 3mm wide x 4mm long x 4mm high layered bead of hot glue on the hub of a few.
* * * * * * * * *
And eluminer, glad to see you're back! Thought you had quit making vids.
Log In to reply
eluminerRC on July 11, 2013
Don't worry, I'm not planing to quit any time soon. Sometimes I just have other (more important) things to do in my life so videos are a bit far apart, but I will continue making them for a while.
Log In to reply
Tom Clark on May 20, 2014
I third that the Gemfan hubs are out of balance ! So annoying to balance!
Log In to reply
Hanzo on July 10, 2013
That was a very nice, clear video (and the moose cups are a nice touch). Thank you - I will check out your other videos.
Log In to reply
apache64 on July 7, 2013
Another great video, I always balance the props, but today I learnt the importance of balancing the hubs. I think if your hub is so heavy on one side, I think I would drill some small holes in it to remove some material thus saving in using too much CA. Great work keep them coming..!
Log In to reply
eluminerRC on July 7, 2013
Thanks! ;)
Log In to reply
Budge72 on July 9, 2013
Nice video. I'm building a tricopter, and this is very helpful. My only question is how do you know that your balancer is balanced? Reviews on HK for all of the balancers are a mixed bag.
Log In to reply
eluminerRC on July 9, 2013
Thanks and excellent question. With this method, you don't. :) I have DIY magnetic balancer which is so sensitive that I can determine if the balancer (shaft and cones) is balanced. This is why I called this "simple" balancing. I'll do more advanced tutorial in future related to this issue, but not for now.
And yes, these cheap balancers are usually unbalanced. :(
Log In to reply
UpSideDownRC on July 23, 2013
Good job !!! I didnt know about hub balancing thanks a lot !!!
Log In to reply
FoamFlyinFool on August 21, 2014
Wow Thanks for the Video
Log In to reply

You need to log-in to comment on articles.

How to - Simple propeller balancing