Does Prop wieght matter?

[Bakersfield Quad]

OK, I was balancing 3 sets of new props today, 6 pairs of silver and black, P4P quick disconnect type. First thing that I did was to weigh each prop, placing them next to the best match of the same color ring as I weighed them.

What I found was surprising! The lightest prop was 11.0 grams (Silver blade) but the heaviest was 11.59 grams (black blade). That is quite a difference.

I found that adding tape to the light blade, for balance, the two props became closer to the same weight with each pair. Making paired sets, Silver and Black, I managed to get the individual pairs within .13 grams of each other in the end.
I thought about sanding off some meat on the heaviest one, but since the match was within .13 grams, I thought it was not necessary and might be worse in the end, removing plastic.

So, what do you think? Does it matter that none of the new props from their pair cases, matched by weight, makes me wonder about whether this could influence crack formation, due to imbalance both in spin balance and actual weight.

By matching them as close as possible, you can get them nearly balanced, weight wise. Maybe with 5-6 pairs, you could find very close matches, but maybe not.

After balance, there was still the .59 difference overall between the 6 pairs of blades. Seems rather high to me, over half a gram, but of course maybe the motor controller would just compensate.

 

[Fly Dawg]

That would be very hard to find out. But I would say that most of the physical weight of the props is along the center line on the hubs. That would not be a huge issue. On the outer props themselves, then that may be the case. If they are properly balanced, regardless of overall weight, I would not be too concerned with it. The problem occurs on the outer edges. I.E. imbalance, causes the "washing machine effect", spin cycle to be exact. That will certainly cause stress cracks in that scenario.

 

[Kirby Johnson]

OK, I was balancing 3 sets of new props today, 6 pairs of silver and black, P4P quick disconnect type. First thing that I did was to weigh each prop, placing them next to the best match of the same color ring as I weighed them.

What I found was surprising! The lightest prop was 11.0 grams (Silver blade) but the heaviest was 11.59 grams (black blade). That is quite a difference.

I found that adding tape to the light blade, for balance, the two props became closer to the same weight with each pair. Making paired sets, Silver and Black, I managed to get the individual pairs within .13 grams of each other in the end.
I thought about sanding off some meat on the heaviest one, but since the match was within .13 grams, I thought it was not necessary and might be worse in the end, removing plastic.

So, what do you think? Does it matter that none of the new props from their pair cases, matched by weight, makes me wonder about whether this could influence crack formation, due to imbalance both in spin balance and actual weight.

By matching them as close as possible, you can get them nearly balanced, weight wise. Maybe with 5-6 pairs, you could find very close matches, but maybe not.

After balance, there was still the .59 difference overall between the 6 pairs of blades. Seems rather high to me, over half a gram, but of course maybe the motor controller would just compensate.

I'd say individual prop balance is important, but prop to prop weight differences are of no concern. IE tires are fairly well balanced revolution wise, per tire, but weigh nowhere the same tire to tire.

 

[Bakersfield Quad]

I'd say individual prop balance is important, but prop to prop weight differences are of no concern. IE tires are fairly well balanced revolution wise, per tire, but weigh nowhere the same tire to tire.

If we are talking pisitraction 4 wheel drive, that would possibly be similar.

But, these 4 props are each driven by its own motor, which would require the controller to keep it all in BALANCE. Not sure this is a problem, just thought it might be a possible influence.

 

[Bakersfield Quad]

I'd say individual prop balance is important, but prop to prop weight differences are of no concern. IE tires are fairly well balanced revolution wise, per tire, but weigh nowhere the same tire to tire.

Agreed, dynamic balance is certainly more of a concern.

 

[yorlik]

So those of us with cheap unbalanced .99 cent unbalanced mismatched weight props flying for 3+ year are in trouble and going to hurt our machines?? ;

Perhaps this is of no consequence at the end of the day?

 

[Bakersfield Quad]

So those of us with cheap unbalanced .99 cent unbalanced mismatched weight props flying for 3+ year are in trouble and going to hurt our machines?? ;

Perhaps this is of no consequence at the end of the day?

Well, that is why we ask questions, to gain individual experiences, thank you for yours.

 

[yorlik]

Tnx for posting your wonderful telescope pix of galaxies! ( I cannot find that thread again to say it there)

 

[Bakersfield Quad]

Tnx for posting your wonderful telescope pix of galaxies! ( I cannot find that thread again to say it there)

Floyd Blue
Well, thank you, I am so happy that you liked my astronomy images. This is my web site.
I can't wait until I can m make a video worth putting in the gallery.