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May 09, 2019, 08:59 PM
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Zenoaheli's Avatar
No thrust numbers yet, but its fully ducted and the intake sounds super wooshy
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May 09, 2019, 11:26 PM
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Quote:
Originally Posted by PeterVRC
Did you get any thrust numbers from it?
That is more linked to the motor quality, and if a HET is not running smoking hot it is likely to be very(?), quite, efficient.
You would hope to be in the region of at least 1.4 : 1 Thrust to Watt..... and even better if more towards 1.5
So..... 6000 x 1.4 = 8.4 Kg (9.0Kg at 1.5)
Oh... but in-plane loss, so maybe (hopefully) 7.0Kg at least. (7.5Kg?)
Theres a third variable abd thats efflux bud
May 09, 2019, 11:44 PM
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...


$60 For this balanced " alloy " 90mm rotor from Xflite is Way much safer, much cheaper than
the cost of a surgery. :-]
But ... be all you can be :-)

..
May 10, 2019, 12:10 AM
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Efflux... true... but CS12's are not good at that, so the base value to use is Thrust really.
If you 'create' high efflux in a 'high blade to gap ratio' fan, you stunt it badly... so you can't make CS12's give good/high efflux.... but they excel at Thrust.
May 22, 2019, 01:57 PM
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https://www.ebay.com/itm/Kntiwiwo-50...72.m2749.l2649

i plan to re arrange the blades in the hub based on weights. There are quite a few ways all 12 blades can be seated and each will have slightly different vibration characteristics.
May 22, 2019, 07:55 PM
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Lol, yes....
12x11x10x9x8x7x6x5x4x3x2x1 =..........
(12 factorial... 500 million ways....)

Well really.... being a 'circle' it needs a bit of additional reduction in permutations. I can't think of what specifically right now..... but it won't be 500mill, though still a very big number.
(it might be close to effectively 11 factorial?)
Not being a "straight line" the FIRST blade is part of a 'loop'. But all following blades are effectively in a line... thus factorial 11 I think..... 40 million....
Last edited by PeterVRC; May 22, 2019 at 08:01 PM.
May 22, 2019, 08:00 PM
The best in EDF since 2005
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Quote:
Originally Posted by flylow2011
$60 For this balanced " alloy " 90mm rotor
What's the exact diameter of the rotor? Its not something you can easily change like a molded rotor so rather important when fitting to various shrouds. 5mm shaft? Would have been nice to see a precision collet adapter rather than grub screws.

I agree with everyone else, no way I would stand near that CS12 at 6kw, not at 3kw having dodged the blades of one earlier this year at our local field that was sitting on a stand in exactly the same position as the video one!
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May 22, 2019, 08:04 PM
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If you use a 'good' motor, so that the motor imbalance can be taken as negligible, THEN you could weigh each blade and use MATHS to determine the one optimal pattern to set them all.
Saving 40 million tests.... hehe
May 22, 2019, 10:20 PM
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Quote:
Originally Posted by Extreme_RC
I agree with everyone else, no way I would stand near that CS12 at 6kw, not at 3kw having dodged the blades of one earlier this year at our local field that was sitting on a stand in exactly the same position as the video one!
lol and you call yourself extreme rc; this is surely not for pussy cats, you have to understand that this material is the same stuff being used on helicopter blade grips that take more abuse.

the arrangement will be based on symmetry, should be fun !
May 22, 2019, 10:56 PM
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But this CS12 use is with 'keyed' hub parts for the blades - which are sharp squared edges, and that is where their weak point is. They have blown up on even 3KW, so that is the guideline/proof it can happen. Let alone higher power levels.
This means an analogy to any other use of fiber reinforcement use or case is irrelevant - seeing the proof of occurrence is here for the CS12 (numerous cases of).

Mind you, it seems YOURS has survived... so far. So that is interesting, somewhat impressive, of that specific CS12.
May 22, 2019, 11:26 PM
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Certainly not for pussy cats, seems crusty the clown is in town though....
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May 23, 2019, 12:13 AM
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Zenoaheli's Avatar
well after blowing up a few fans i realized that it was user error on my part. I blew up a cs120 fan on less than 3 kw, so your 3kw bench mark doesnt mean diddly squat if the fan isnt assembled and running right.
And No it seems like its you blokes from Australia that like to clown for some reason
May 23, 2019, 04:16 AM
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Quote:
Originally Posted by Zenoaheli
well after blowing up a few fans i realized that it was user error on my part. I blew up a cs120 fan on less than 3 kw, so your 3kw bench mark doesnt mean diddly squat if the fan isnt assembled and running right.
And No it seems like its you blokes from Australia that like to clown for some reason
Where did I say 3Kw was a benchmark? Jeez you love to argue with yourself
Latest blog entry: Extreme RC AUSTRALIA
May 23, 2019, 09:14 AM
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fortunately you are not the only one in this conversation
May 23, 2019, 06:23 PM
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Quote:
Originally Posted by Zenoaheli
fortunately you are not the only one in this conversation
What is unfortunate is there are many who read these threads and then go and follow what is being touted as safe, sometimes ending up in the emergency department wondering what the hell happened...

The members in here who have shown concern for what has been posted have every right to do so. You are entitled to do whatever you like with the product no one will deny that, but when you put it out in public others are entitled to voice their concern over the safety and danger of what you are doing if only to save someone else not familiar with the product from injuring themselves.
Latest blog entry: Extreme RC AUSTRALIA


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