What about balancing by lightly sanding the ends of the prop tips? Maybe one side is a hair longer than the other side anyway? IF it balances out that way, why would it NOT be balanced? Thanks.
I am having trouble, I got props to balance horizontal then I put them vertical and started to sand the heavy side which I determined by watching which way the prop fell. I was getting close too vertical balance when I decided to check the horizontal balance(which was good earlier) and now it was off favoring the opposite side from the initial balance?
BTW, I would be adding material to the light side, not sanding on the heavy side. Its easier to remove what you've added than it is to replace what you have removed. Scotch tape works just fine. But, to minimize the effort and amounts used, when adding, use something like the heavy foil HVAC tape.Always apply your balance weight to the underneath of the propeller blade, never on top.
Actually if you are adding tape ... then the Helicopter boys have the best way. You take a piece of clear tape ... (Heli boys often use coloured to give visual tracking) ... fold it over the leading edge and press smooth both sides of blade ... meeting at trailing edge. Sharp knife - slice flush to trailing edge. Why ? This then gives a corrector with no edge that airflow can lift. Its thin enough to not affect aerodynamics of blade.
No. The propeller works on lift, created by the vacuum above the blade, not pressure underneath. Sanding on the bottom of the blade will not affect it's function.
Sorry but bad sanding will. Extreme fine sanding is called for along the blade rear face. Bad sanding and causing rough surface will create turbulence on the rear face. The lift as you call it is based on two factors : RPM of the blade and PITCH of the blade as the prop WALKS forward in the air. The prop is basically an air pump.... driving the air rearwards and itself pulling forwards.
NEVER sand front face ... and avoid sanding in one area ... tip or hub. Try to sand along the underside of blade ... avoid altering edges. If the blade is significantly out of balance as in typical slow fly props ... then fold clear tape over leading edge of light blade ... joining at trailing edge ... cut flush. This is similar to what Helicopter boys do.
I've studied aerodynamics. Both as an interest and also part of my training as a flight paramedic. The principle of lift (and yes, that is the correct word) is that as the blade spins (or with a fixed wing aircraft, the wing moves forward) a vacuum is created above the wing, providing lift. Poor sanding will not help. But, sanding the underside of the propeller blade to reduce the weight of that blade will not affect lift.
Hello Iftibashir, it doesn't sound like there is a place, here in the U.S., to purchase the additional ROD for balancing the DJI self tightning props, so if you still have that additional rod I would very much like to get it from you, no problem paying you for the postage, is it still available??
Because its not supposed to be used on top of both sides - it would just topple over from the weight of the prop on one side. The video highlights the correct way of using the balancer.
I know that I'm replying to a post that is over a year old. But, I thought it would be worth posting anyway. Whether you are using the Dubro or the Speedy, this IMHO is the best method of doing a static AND dynamic balancing of your propeller. First, place the prop horizontal on the balancer, and mark the light END. Then, place the prop vertical on the balancer, first with the light end up, and then with the heavy end up. Do this a few times, to find the light SIDE. Now you have a starting point to do both your static and dynamic balancing at the same time. Add tape to the light side of the light end, close to the center of length of the blade.Repeat this process, checking both the horizontal and vertical balance of the blade at the same time. At some point, you will have to start making adjustments by either adding to the other SIDE for the dynamic balance and/or continue to add to the light END for static balance, but at the center of the blade,not at the edge of the what was the light side. You may even have to remove a little of the weight that you've already added by trimming off a little of the tape with a razor knife. Note: if the blade is only slightly out of balance, after adding some tape, near the center of the length of the blade, you can reposition the tape either further out or closer in, relative to the hub, to achieve balance.
Theres a massive flaw in this video... im doing a video on it myself now. The shaft enters the thread and there is play so you can never scre it in the same position twice. This means that the hub will always be out of alignment and it causes massive vibrations if you balance the hub! Just try putting the 6mm bar through and seeing how it seats, then grab the prop and press in several directions. See how the hub moved. Game over! Im going to contact Dubro asking if there is a solution. MY props were better balanced before I put them on after the Bubro balance and this is not right. Needs a fix.
Because Video shows WRONG way to use rod in DJI props. It needs the brass / bronze bush on the rod that is a snug fit to the DJI prop hub. Using the silicon tube is purely to keep brass bush in place ... NOT to centre the prop ...
I was thinking about buying DJI Phantom 2, but now my opinion has changed. I'm not a handy man and balancing props just does not sound like me. :) £ 700 for a Phantom is just the beginning.
Simplest way is for people to actually use it correctly and not be led by mis-information. The DuBro manual sucks ... and the OCDay / Oday manual at least is better and gets it mostly right.
Oh, I forgot, very informative video. Thanks and Merry Christmas
What about balancing by lightly sanding the ends of the prop tips? Maybe one side is a hair longer than the other side anyway? IF it balances out that way, why would it NOT be balanced? Thanks.
where do I get one of those shafts for my blade chroma????
I am having trouble, I got props to balance horizontal then I put them vertical and started to sand the heavy side which I determined by watching which way the prop fell. I was getting close too vertical balance when I decided to check the horizontal balance(which was good earlier) and now it was off favoring the opposite side from the initial balance?
How to make sure that the rod is perfectly levelled for the screw in type rod ?
The rod can be purchased from Speedy Prop Balancer, it is CNC machined to exact specfications.
And I use a tiny bubble level when making sure the aluminum Speedy Prop rod is level.
BTW, I would be adding material to the light side, not sanding on the heavy side. Its easier to remove what you've added than it is to replace what you have removed. Scotch tape works just fine. But, to minimize the effort and amounts used, when adding, use something like the heavy foil HVAC tape.Always apply your balance weight to the underneath of the propeller blade, never on top.
Excellent tips - thanks you!
Any time, friend. Good video. Keep up the great work!
Actually if you are adding tape ... then the Helicopter boys have the best way. You take a piece of clear tape ... (Heli boys often use coloured to give visual tracking) ... fold it over the leading edge and press smooth both sides of blade ... meeting at trailing edge. Sharp knife - slice flush to trailing edge. Why ? This then gives a corrector with no edge that airflow can lift. Its thin enough to not affect aerodynamics of blade.
Doesn't sanding cause the surface of the prop to have air turbulence?
No. The propeller works on lift, created by the vacuum above the blade, not pressure underneath. Sanding on the bottom of the blade will not affect it's function.
So only the bottom side is what gets sanded. Got it.
Sorry but bad sanding will. Extreme fine sanding is called for along the blade rear face. Bad sanding and causing rough surface will create turbulence on the rear face. The lift as you call it is based on two factors : RPM of the blade and PITCH of the blade as the prop WALKS forward in the air. The prop is basically an air pump.... driving the air rearwards and itself pulling forwards.
NEVER sand front face ... and avoid sanding in one area ... tip or hub. Try to sand along the underside of blade ... avoid altering edges. If the blade is significantly out of balance as in typical slow fly props ... then fold clear tape over leading edge of light blade ... joining at trailing edge ... cut flush. This is similar to what Helicopter boys do.
I've studied aerodynamics. Both as an interest and also part of my training as a flight paramedic. The principle of lift (and yes, that is the correct word) is that as the blade spins (or with a fixed wing aircraft, the wing moves forward) a vacuum is created above the wing, providing lift. Poor sanding will not help. But, sanding the underside of the propeller blade to reduce the weight of that blade will not affect lift.
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Hello Iftibashir, it doesn't sound like there is a place, here in the U.S., to purchase the additional ROD for balancing the DJI self tightning props, so if you still have that additional rod I would very much like to get it from you, no problem paying you for the postage, is it still available??
Michael Aguirre I'll see if I still have it ;o)
Cool, thanks, I actually spoke to Du Bro, and they are not interested in making one, ????? Oh well, maybe a small side biz for someone.
Thx,
Mije
+Michael Aguirre you probably know this by now, but 1 year later and du-bro does make a rod for the P3 self tightening props.
But its not necessary if you use the supplied gear correctly.
Hi iftibashir, can I buy the balancer shaft for the DJI props somewhere?
Maikel van den Wildenberg Where abouts are you based? I think I have a spare ;o)
Thanks for your reply, I ordered one in the UK for 11 GBP , I live in the Netherlands.
why are you not resting it on top of both sides?
Because its not supposed to be used on top of both sides - it would just topple over from the weight of the prop on one side. The video highlights the correct way of using the balancer.
Mine stays up ok..
I know that I'm replying to a post that is over a year old. But, I thought it would be worth posting anyway. Whether you are using the Dubro or the Speedy, this IMHO is the best method of doing a static AND dynamic balancing of your propeller. First, place the prop horizontal on the balancer, and mark the light END. Then, place the prop vertical on the balancer, first with the light end up, and then with the heavy end up. Do this a few times, to find the light SIDE. Now you have a starting point to do both your static and dynamic balancing at the same time. Add tape to the light side of the light end, close to the center of length of the blade.Repeat this process, checking both the horizontal and vertical balance of the blade at the same time. At some point, you will have to start making adjustments by either adding to the other SIDE for the dynamic balance and/or continue to add to the light END for static balance, but at the center of the blade,not at the edge of the what was the light side. You may even have to remove a little of the weight that you've already added by trimming off a little of the tape with a razor knife. Note: if the blade is only slightly out of balance, after adding some tape, near the center of the length of the blade, you can reposition the tape either further out or closer in, relative to the hub, to achieve balance.
sorry, realized this is for self tightening props which makes sense why it is set up this way
Theres a massive flaw in this video... im doing a video on it myself now. The shaft enters the thread and there is play so you can never scre it in the same position twice. This means that the hub will always be out of alignment and it causes massive vibrations if you balance the hub! Just try putting the 6mm bar through and seeing how it seats, then grab the prop and press in several directions. See how the hub moved. Game over! Im going to contact Dubro asking if there is a solution. MY props were better balanced before I put them on after the Bubro balance and this is not right. Needs a fix.
Because Video shows WRONG way to use rod in DJI props. It needs the brass / bronze bush on the rod that is a snug fit to the DJI prop hub. Using the silicon tube is purely to keep brass bush in place ... NOT to centre the prop ...
not a big fan for the Du-Bro, seems like a get a different reading every time
Try the Speedy Prop balancer. Simpler, no moving parts. More accurate.
I was thinking about buying DJI Phantom 2, but now my opinion has changed. I'm not a handy man and balancing props just does not sound like me. :)
£ 700 for a Phantom is just the beginning.
I can show u how to improve ur balancers
Look up improving ur balancer
Simplest way is for people to actually use it correctly and not be led by mis-information. The DuBro manual sucks ... and the OCDay / Oday manual at least is better and gets it mostly right.