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Old Nov 27, 2012, 07:23 PM
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Quote:
Originally Posted by alexandermh View Post
OK, I'm trying to get some measuring here and not be too confusing. You know how both rotors have a raised circular area on the face of the rotor?

On the 10 blade rotor, the diameter of that ridge is 26.56mm. The diameter of the entire rotor face is 29.62mm. The inside diameter of the Tams washer is 26.62mm and the outside diameter for the Tams spinner is 29.51mm.
On the new 12 blade rotor, the diameter of that ridge is 27.86mm. The diameter of the entire rotor face is 30.53mm and the outside diameter of the Change Sun aluminum spinner is 30.53mm. I did these measurements with my small digital caliper so they may be off in the hundreth mm area.

So it looks like the Tams washer doesn't fit that circular ridge, and is also smaller in overall diameter. In addition, the Tams spinner is smaller in diameter than what is needed for the 12 blade rotor. So either Tam has to make a new washer which fits the new Change Sun aluminum spinner or a new washer and spinner. Also, with these pretty small differences, you are also probably right that Tam could just turn down the washer a bit so as to fit the circular ridge on the 12 blade rotor, but then you would have to also use the Tam spinner (which are nice but I'm hoping to be able to use these $2 aluminum spinners from Change Sun). Sorry for the long post.
ok thanks for taking the measurements sounds like we should wait until we have some in our hands and then see how they perform
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Old Nov 28, 2012, 01:25 AM
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Quote:
Originally Posted by Watakashi View Post
Hello guys,
I've received my new 12 blades CS version and would like to say the differences about spinners but it seems Alexander has been faster than me
I've ordered two alum spinners to try the second one in my CS10 blades but there's effectively too much clearance and the spinner is not well centered in the CS10. I've also noticed that the new one has a better centering than the CS10 (the centering ring on the new CS12 is more prononced than the CS10 and so when you put the spinner on you really feel a good "clip". The material seems to be different too, and what strike me the most is the shroud, which is completely different (there's 6 stators (or 8 I can't remember and it's in the garage now so I have to check tomorrow), and the cylinder where the motor fits has grooves on it (better for cooling but I guess it won't deform and cause bad centering of the rotor in high stress)
The housing has two external rings too to increase rigidity I think whereas the CS10 didn't, and there's no Change sun engraving like his sister.
Hope you'll understand my english :-)
Have a nice evening everybody
Rdgs
Aurelien
Your English is excellent Aurelien, and that was a really good engineering assessment of the new 12 blade fan. The changed features you describe indicate that some well-thought-out engineering improvements will have been made by the manufacturers - i can't wait for the boys (well, i assume there's no girls interested in this???) to get testing and produce some performance results for us.

Rgs, Andy
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Old Nov 28, 2012, 05:28 AM
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CS12 70mm - Test/Review Pt.1

I made some time to go over the new CS12 70mm fans I got the other day. Normally I would have been 'excited' and do it all right away, but I had other 'more exciting' things to do.... so it had to wait until now.

The Pics below have notes on each:

The housing was made out of the same stuff the larger 90mm CS12 is. So it is a much stiffer and robust housing now. The CS10 plastic was FLIMSY!
The 12 blade rotor is also quite solid and robust, so it is likely this unit will have the ability to go to a fair way higher power levels than the CS10 can.

The motor wire 'exit hole' is not designed very well. The CS10 allowed it to stay low and rearwards of the rotor, but these don't. They were still even dangerous in the CS10, but they are very dangerous in this CS12!!! It is very easy for the wiring to move forwards and be cut by the rear rotor hub lip - so I filed that wiring hole out to allow the wiring to be more rearwards and be SAFE!

The shaft adaptor hole in the motor housing hub is too small really. Firstly, the sahft adaptor has to be pushed right down onto thte motor shaft, like in the CS10, because the rotor blade front edges JUST stay inside the housing then. The shaft adaptor JUST fits the centre hole, but after I centred the fan in the housing the adaptor rubbed on one side of that hole. So I used a round file to open the adaptor hole by approx 1mm diameter to assure it always clears the shaft adaptor. Once again the loss of material is irrelevant as it is all very strong.

As usual I filed opposing flats on the shaft adaptor end, so I can use two shifting spanner to do up the rotor nut.

Static balancing the rotor it needed 4 pieces of 25mm wide x 5mm strips of fibre tape to one side. When run up it was quite good, but not perfect. Adding the spinner didn't alter anything.
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Old Nov 28, 2012, 05:42 AM
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Great review Peter!

Now, are you gonna share the measurements of the L2855-2300kv with us...
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Old Nov 28, 2012, 05:43 AM
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CS12 70mm - Test/Review Pt.2

The test(s) were done on the 'old faithful' 5S optimal Turnigy L2855-2300kv motor.

I first ran it up on 4S to see how much more load it has than a CS10.

Settled figues:

4S 3000mAH 40C Turnigy
36.7 Amps (41 Ap)
523 Watts (613 Wp)
1.04Kg Thrust (1.12Kg Peak)

That was a little bit lower than my CS10 tests had on that same battery.
[41.2A 580W 1.09Kg Thrust]

So then it was all clear to move ot 5S:

5S 4000mAH 40C Zippy
54.9A (63.5Ap)
1045W (1234Wp)
1.52Kg Thrust (1.75 Kg Peak)

This time it was a bit pretty much the same thrust result, though some values different, than my CS10 results on the same battery!!
[50.9A 974W 1.53Kg Thrust]

But all in all they are the same.
Sound-wise.... hard to know definitely, but sounds very similar - it will be interesting to see it in a plane,

So as far as I can see the main benefit will be for higher power usage. eg 6S
Because the housing and rotor/fan will very likely cope with a LOT more power than the CS10. Other than that higher level of power, it makes no difference to use the CS10 or CS12.

This combo cost me:
CS12 $15
Spinner $2
Motor $13
= $30

If you wanted to run on 6S then you will need a much better motor. Starting in the $40 area for that, out to $75 area. Which then means $57 or so all up. ($40 not being a 'great' motor option, as per a HET at $75 area)
I paid $66 for the Lander 6S CS10 based ALLOY 2200kv based EDF unit!!! $9 more to have a pre-assembled and balanced ALLOY's solution. $9 more is peanuts for all that!!
That then negates the use of the CS12 70mm 'greater strength' to allow high power 6S use!! I guess if you wanted to save a BIT of weight.....
It means there is only a very narrow window of real use for the CS12 70mm

At the lower power uses, the CS12 70mm is just line-ball with the CS10 because they will both run fine even to 'fairly high power' combo levels. eg 6S HET 2200kv (1200W or so area) - the same end result as the Lander alloy. But costs MORE, for plastic! (which you might want to save weight....???)
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Old Nov 28, 2012, 06:00 AM
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Quote:
Originally Posted by PeterVRC View Post
I first ran it up on 4S to see how much more load it has than a CS10.

Settled figues:

4S 3000mAH 40C Turnigy
36.7 Amps (41 Ap)
523 Watts (613 Wp)
1.04Kg Thrust (1.12Kg Peak)

That was a little bit lower than my CS10 tests had on that same battery.
[41.2A 580W 1.09Kg Thrust]

So then it was all clear to move ot 5S:

5S 4000mAH 40C Zippy
54.9A (63.5Ap)
1045W (1234Wp)
1.52Kg Thrust (1.75 Kg Peak)

This time it was a bit pretty much the same thrust result, though some values different, than my CS10 results on the same battery!!
[50.9A 974W 1.53Kg Thrust]

But all in all they are the same.
Sound-wise.... hard to know definitely, but sounds very similar - it will be interesting to see it in a plane,

So as far as I can see the main benefit will be for higher power usage. eg 6S
Because the housing and rotor/fan will very likely cope with a LOT more power than the CS10. Other than that higher level of power, it makes no difference to use the CS10 or CS12.

This combo cost me:
CS12 $15
Spinner $2
Motor $13
= $30

If you wanted to run on 6S then you will need a much better motor. Starting in the $40 area for that, out to $75 area. Which then means $57 or so all up. ($40 not being a 'great' motor option, as per a HET at $75 area)
I paid $66 for the Lander 6S CS10 based ALLOY 2200kv based EDF unit!!! $9 more to have a pre-assembled and balanced ALLOY's solution. $9 more is peanuts for all that!!
That then negates the use of the CS12 70mm 'greater strength' to allow high power 6S use!! I guess if you wanted to save a BIT of weight.....
It means there is only a very narrow window of real use for the CS12 70mm

At the lower power uses, the CS12 70mm is just line-ball with the CS10 because they will both run fine even to 'fairly high power' combo levels. eg 6S HET 2200kv (1200W or so area) - the same end result as the Lander alloy. But costs MORE, for plastic! (which you might want to save weight....???)
which motor are u using for the above test? the thrust doesnt seem to improve much?
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Old Nov 28, 2012, 06:05 AM
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Australia, VIC, Melbourne
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Oh... ooops...
Turnigy L2855-2300kv

I was going to run a 2100kv test also but it will be the same as the CS10 anyway. So I can't be bothered setting that up, and will use the second CS12 with another 2300kv in that too.
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Old Nov 28, 2012, 06:11 AM
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Originally Posted by PeterVRC View Post
Oh... ooops...
Turnigy L2855-2300kv

I was going to run a 2100kv test also but it will be the same as the CS10 anyway. So I can't be bothered setting that up, and will use the second CS12 with another 2300kv in that too.
u are the man!!! mate. thanks for the first hand detailed testing!

u hv any 3300kv to 3400KV motor for testing on CS12 on 4S setup?
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Old Nov 28, 2012, 06:24 AM
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You would want a GOOD... hmm, VERY GOOD..... motor to run 3300kv in the CS10 or CS12 !!
2800kv does 56Amps or so. (some setups would go over 60A)
So by 3300kv..... ????..... 70A or more. Even 80A? Thus would need a good motor to cope with that. eg a HET 2W20 3350kv a 28x 43mm motor.... pushing it a bit maybe?. Otherwise a HET 1W40 3300kv a 28x62mm motor which should do it fine (overrkill???) (and $82 or so!)
If the motor can do it (not too weak - which the 1W40 would be fine), it would do something like 1100 to 1200watts. Not a lot more than the $30 5S L2855-2300

At those current levels (Amps) you would be far better off with a 6S Lander!! That $66 alloy combo. All up it would be cheaper, a bit heavier (no real issue) and more powerful.
http://www.hobbyking.com/hobbyking/s...7-B59C19B8A4A7
I don't know if buddy codes work unless you are a logged in HK member (probably not?).
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Old Nov 28, 2012, 06:56 AM
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Rutland, England
Joined Feb 2005
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Quote:
Originally Posted by PeterVRC View Post
The test(s) were done on the 'old faithful' 5S optimal Turnigy L2855-2300kv motor.

I first ran it up on 4S to see how much more load it has than a CS10.

Settled figues:

4S 3000mAH 40C Turnigy
36.7 Amps (41 Ap)
523 Watts (613 Wp)
1.04Kg Thrust (1.12Kg Peak)

That was a little bit lower than my CS10 tests had on that same battery.
[41.2A 580W 1.09Kg Thrust]

So then it was all clear to move ot 5S:

5S 4000mAH 40C Zippy
54.9A (63.5Ap)
1045W (1234Wp)
1.52Kg Thrust (1.75 Kg Peak)

This time it was a bit pretty much the same thrust result, though some values different, than my CS10 results on the same battery!!
[50.9A 974W 1.53Kg Thrust]

But all in all they are the same.
Sound-wise.... hard to know definitely, but sounds very similar - it will be interesting to see it in a plane,

So as far as I can see the main benefit will be for higher power usage. eg 6S
Because the housing and rotor/fan will very likely cope with a LOT more power than the CS10. Other than that higher level of power, it makes no difference to use the CS10 or CS12.

This combo cost me:
CS12 $15
Spinner $2
Motor $13
= $30

If you wanted to run on 6S then you will need a much better motor. Starting in the $40 area for that, out to $75 area. Which then means $57 or so all up. ($40 not being a 'great' motor option, as per a HET at $75 area)
I paid $66 for the Lander 6S CS10 based ALLOY 2200kv based EDF unit!!! $9 more to have a pre-assembled and balanced ALLOY's solution. $9 more is peanuts for all that!!
That then negates the use of the CS12 70mm 'greater strength' to allow high power 6S use!! I guess if you wanted to save a BIT of weight.....
It means there is only a very narrow window of real use for the CS12 70mm

At the lower power uses, the CS12 70mm is just line-ball with the CS10 because they will both run fine even to 'fairly high power' combo levels. eg 6S HET 2200kv (1200W or so area) - the same end result as the Lander alloy. But costs MORE, for plastic! (which you might want to save weight....???)
Excellent review and interesting resuts Peter, many thanks for producing them so quickly for everyone.

If your rig is still set up (but don't bother if it isn't) i'd be really VERY interested to see the 5S set up running at part throttle, such that it gives around the same thrust as the 4S set up (ie around 1Kgf) - that way we could get a direct comparison of the g/w when running at similar levels of thrust. I'd expect/hope that the 5S set up would give slightly better g/w figures (due to theoretically less heat losses in the motor) - what do you think?

Another question for you, with all your experience of this model and it's propulsion systems:
Could you suggest a ball-park figure to use to questimate the (static) thrust we might see in the model (with cowl etc in place - ie 'sealed up') as opposed to the thrust figures we might see on the bench? Like might it be around 80%(ish)?

Many thanks in advance,

Andy
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Old Nov 28, 2012, 08:21 AM
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hehe... no formula for in-plane loss, as they vary so much!
I guess I would say I commonly see something like 1.5Kg going to 1.2Kg is a fairly good ducting system. eg Habu
I have to re-test my Me-262 which has nacelles to see what those lost - it weighs 3.5Kg and is fast and very powerful, can climb very steep angles long term, so maybe 3.0Kg thrust. (which the CS10 L2855-2300kv 5S does 1.5Kg on the bench. The nacelle uses the inlet lip and is extremely free flowing all in all, so possible it is over 90% efficient.

I have videos of the tests, so I can freeze frame a point where throttle/thrust is 1.0Kg as per 4S. And see what its values all were at that moment.
These pics below are on the throttle up, and then the throttle down, sides of the test - a it passes through 1.05Kg thrust approx. Which is what 4S does at full throttle (after settling).

I see the RPM readout is whacko though! LOL. Different on the up and down sides! It must be lagged by some reasonable amount, thus why it is different on the up and the down sides.
Going upwards it has not reached showing what the true RPM are then, and going down it is still too fast as it is slow to move the RPM down as per the true value.
I never noticed that before..... but I only really look at it for constant speeds.

...
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Old Nov 28, 2012, 10:56 AM
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Originally Posted by PeterVRC View Post
I have videos of the tests, so I can freeze frame a point where throttle/thrust is 1.0Kg as per 4S. And see what its values all were at that moment.
These pics below are on the throttle up, and then the throttle down, sides of the test - a it passes through 1.05Kg thrust approx. Which is what 4S does at full throttle (after settling).

I see the RPM readout is whacko though! LOL. Different on the up and down sides! It must be lagged by some reasonable amount, thus why it is different on the up and the down sides.
Going upwards it has not reached showing what the true RPM are then, and going down it is still too fast as it is slow to move the RPM down as per the true value.
I never noticed that before..... but I only really look at it for constant speeds.
...
Problem with these video snapshots Peter is that all three instruments are likely to have different sampling periods - and all start at slightly differing instances; hence i don't think we could really use data like this for anything other than reading stuff once everything has settled at a test point (like you normally do). The numbers we get from the snapshots don't stack up - ie you're getting a g/w of 1.89/1.77 for the 5S jobbie, and 1.99 on the 4S set up; i don't think this can be right I'd expect a g/w something>2 for the 5S set up at around 1Kgf, wouldn't you?

Never mind - thanks v. much anyway for trying to extract/derive the info i requested. I think you've already proved though, that the 2855-2300 motor is still the right one in combination with 5S for this new fan. I'll maybe just have to be patient until i get my own kit so i can start doing some g/w experimentation of my own.

One further question: what sort of RPMs were you registering at max power? (I may need to purchase a new tacho... i think mine only reads up to 100K rpm on a three bladed prop - so i think these edf 12 bladers at full-chat may send it out of it's range!)

Many thanks anyway.

Rgs, Andy
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Old Nov 28, 2012, 01:22 PM
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Thanks for the review Peter, and I would agree, it would appear this new fan becomes relevant in the very high power range of the spectrum. A reliable setup using a 1W-40 on 5S turning close to 50,000 rpm would be impressive.

On the other hand for most other applications, it's good to know the vanilla CS10 is still a great performer.
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Old Nov 29, 2012, 12:07 AM
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Joined Dec 2008
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I've just bought this fan and I also have a (so far ) Unused het 1w-40 . The biggest problem using the 1w-40 is the mounting holes are nowhere near close to lining up . Het uses a really strange mounting hole pattern on this motor . Which sucks because this housing is really tough and looks like it could take it .I do still have a dollar coin that I used to mount my Het 2w-20 motor to a broken stryker engine mount . I drilled the hole pattern of the 2w-20 into the dollar coin, drilled some holes for cooling and sandwiched it behind the plastic mount .It worked perfectly strengthening up the cracked stock Stryker mount . If I ever do manage to mount the motor I'll definately try it on 5 or 6S . If it blows up the fan well it was only 20 $
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Old Nov 29, 2012, 12:22 AM
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hehe, but it will probably bend the 'expensive motor' shaft too then!!
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