Balancing Xoar props

[DucktileMedia]

I spent over an hour balancing these things which all seem very out of balance! I know they are a natural product but having to do this much work on each prop makes me wonder if it is worth it. My question for the balancing pros is concerning the hub balancing. To start, I have a magnetic balancer and get the blade balanced perfectly horizontal in both directions. Once that is really close I tilt the blade 45 deg and get a feel for the heavy spot, which I am getting to be good at. The uncertainty comes with using to much aluminum tape to balance the hub. I have up to 10 1" layers of aluminum tape at the hub to get it balanced perfectly. Bart told me I am using too long of a piece of tape and they should be smaller to more precisely place the weight but I was concerned the tape wouldnt have enough surface area to adhere to the hub. One way or another if the blade is balanced on the balancer in such a way that it can hold in any position, am I good to go, or is there some negative side effect of having too much balance weight? Obviously this is more rotational mass but I would think it is negligible.

View attachment 6881

 

[PaNt]

Lol same thing here with APC 13 6.5...

This thing is crazy...

 

[tahoelight]

Hub balancing

I am curious about the same thing but with my APC props. My 14x4.7 props all have huge amounts of Velcro/CA glue to balance the hug and the mass sticks out pretty far. I then feel like I get just as much, if not more vibration issues. I have had a really hard time balancing props lately. Almost like the quality control is taking a spiral downhill. Even though they show as balanced on the Du-bro balancer, sometimes they get bad vibration on spin-up. I did not know Xoars would need so much work! Also, it seems counter intuitive, but I wonder about the accuracy of these balancers.
View attachment 6882

 

[PaNt]

I am curious about the same thing but with my APC props. My 14x4.7 props all have huge amounts of Velcro/CA glue to balance the hug and the mass sticks out pretty far. I then feel like I get just as much, if not more vibration issues. I have had a really hard time balancing props lately. Almost like the quality control is taking a spiral downhill. Even though they show as balanced on the Du-bro balancer, sometimes they get bad vibration on spin-up. I did not know Xoars would need so much work! Also, it seems counter intuitive, but I wonder about the accuracy of these balancers.
View attachment 8969

I HAVE THE 14 4.7 and the 13 6.5 the 13 6.5 are 100% unbalanced..! the 14 were a lot better..!

 

[DucktileMedia]

Its harder for me to believe the plastic props are that off. the Xoars are wood so inherently there will be some variation in density.

I've flown APC 12" SF props more than any other prop and they are very easy to balance by just using clear tape on one blade. Normally doesnt take much at all and I have NEVER balanced a hub on them. My video is fine.

 

[siim227]

It's my way. I used sandpaper

View attachment 6886

 

[PaNt]

It's my way. I used sandpaper

View attachment 8973

Its not so good to use sandpaper on the Hub..!

 

[ChrisViperM]

This might help people reading this thread to actually understand (and solve) the discussed problem:

Although the props in this vid are wooden props for FixedWing Airplanes, but the principle applies to all fixed props.

I always use drops of CA glue (for less balancing) or Epoxy Glue (for more balancing)....it's almost invisible, it sticks lick hell and you can "fine tune" it with a fine file or some sandpaper....you can never be that accurate with tape


Chris

 

[PaNt]

I dont think that the video solves the problem..>!!

I cannot understand why the companies that sell the props dont balance their props??!

 

[ChrisViperM]

There is a few rules to success in our "hobby"....always solder electr. connections yourself, always use thread lock on metal/metal screws,...etc....and one of the rules is: balance your props.

The reason why they are not perfectly balanced is price and manufacturing processes....you could get perfectly balanced blades, but are you prepeared to pay double or triple the price....? In the case of wood props, you even have to balance them not only once but propably a few times during their lifetime. Wood is an organic material and reacts to changes of humidity and temperature, but on the other hand they have very good dampening properties. So the question is just to get all informations you need to balance your new pair of props as fast and good as possible....because you won't get away from balancing.

There is another vid I found in the depth of my bookmarks:

Chris

 

[ChrisViperM]

Also be aware that not only the props need balancing........the brushless motors should be balanced as well :

Chris

 

[PaNt]

OK you are right but they can balance at 80-90%...

Also its different if they balance with a machine it wont cost so much..!
Arent there machines that can balance props?? I think that the machines that balances the tires can do the job with some changes..!

 

[SteveWilson]

It's my way. I used sandpaper

View attachment 8973

I use sandpaper on my plastic props, but I thought on wood it was a bad idea because you may remove the polyurethane in spots and the wood then becomes affected by humidity.

 

[Patscherpofel]

just wanted to post the exact same thing

those xoar props give me very hard time
I actually like to balance my props...its nice when you finally have them at the point when they are standing still at each point of the balancer (dubro and another magnetic balancer)
but what really is a pain if this perfectly balanced prop on the balancer runs with vibrations on the motor after...
motors are axis and run smooth, prop adapter is brand new and in center

the real stange thing is, I tested to put some tape randomly on the props to find where the vibrations would get better... I was able to make it better...but the it was heavily unbalanced on the balancer
how is this possible? I have 3 differtn prop balancers..all are saying the same

I have this problem with a lot of xoar props...some less some more...specially with the ones that have a very unbalanced hub
with graupner eprops its much much easier and all the time I manage to balance them perfect

 

[ChrisViperM]

You should also check for the "blade tracking".....very good to see in this vid (first 40 seconds) :

Chris

 

[DucktileMedia]

just wanted to post the exact same thing

those xoar props give me very hard time
I actually like to balance my props...its nice when you finally have them at the point when they are standing still at each point of the balancer (dubro and another magnetic balancer)
but what really is a pain if this perfectly balanced prop on the balancer runs with vibrations on the motor after...
motors are axis and run smooth, prop adapter is brand new and in center

the real stange thing is, I tested to put some tape randomly on the props to find where the vibrations would get better... I was able to make it better...but the it was heavily unbalanced on the balancer
how is this possible? I have 3 differtn prop balancers..all are saying the same

I have this problem with a lot of xoar props...some less some more...specially with the ones that have a very unbalanced hub
with graupner eprops its much much easier and all the time I manage to balance them perfect

that brings up a good point that maybe if our motors arent perfectly balanced then not having a perfectly balanced prop could add to the total amount off balance. I guess you would have to balance your motors. Personally I havent done that yet and I dont have video that comes close to being bad enough to think about doing it. In reality I have been pretty sloppy with my APC balancing and had great results. i think its better to load your props up with the correct amount of weight more than anything. But I also just replaced 2 bearings in my Tmotor 2814's and it is so bad now that I can shake it laterally! And the video from that one bad motor screws everything up completely!

 

[Bowley]

just wanted to post the exact same thing

those xoar props give me very hard time
I actually like to balance my props...its nice when you finally have them at the point when they are standing still at each point of the balancer (dubro and another magnetic balancer)
but what really is a pain if this perfectly balanced prop on the balancer runs with vibrations on the motor after...
motors are axis and run smooth, prop adapter is brand new and in center

the real stange thing is, I tested to put some tape randomly on the props to find where the vibrations would get better... I was able to make it better...but the it was heavily unbalanced on the balancer
how is this possible? I have 3 differtn prop balancers..all are saying the same

I have this problem with a lot of xoar props...some less some more...specially with the ones that have a very unbalanced hub
with graupner eprops its much much easier and all the time I manage to balance them perfect

I've also had a rough time with Xoars, exactly as you described, lesser but similar problem with APC's.
Strangely the motors and props I have had the least vibration trouble from have been Xaircraft. no kidding!!

 

[tahoelight]

Oh, the agony of balancing all of these props. I just got an order of JFX props 12's, 13's and 14's. The hubs are severely wacked!!! I have been balancing for hours and only about half way through. blade balance is actually really consistent, hubs, not so much. I have resorted to sanding one side and adding material to the other.

 

[Vortex]

I balanced my Xoar 15x5 props and was surprised how much weight the hubs took so I added lead strip to the light side of the hubs just as is shown in the first post.

I agree everything rotating should be balanced......It all takes time and is a real PITA but the results are well worth the effort if you take the time to do it properly.

Regards,

Lance

 

[PaNt]

At the end i just recieved my Xoar props..

These are the expensive that are prebalanced (they are all 100% tip balanced but not Hub balanced)... they are nearly perfectly balanced but i have to add some weight...!

Whats the best?? for the tip and for the hub??

For tip is it better to put some tape or clear Coat spray????
And for Hub i think velcro with CA is the best...!

thx..!