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Jan 31, 2013, 03:51 PM
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4stripes's Avatar

I ordered one here for $30.79 shipped.
Turns out now I don't need it! I have come up with a solution to keep the Turnigy 2855-2100 within decent operating spec's. Very simple really, first set the ESC throttle settings to 1.1ms to 1.8ms (not the usual AUTO Throttle range). This allows me to set the upper throttle limit with my upper throttle channel travel on the transmitter. Running the watt meter I set the throttle travel to 30% for the upper half and majically the watts are limited to 2000watts with a full battery (or whatever I want it to be). Now the motor is safely limited, and I will still have plenty of thrust. Don't know why I didn't think of it earlier....
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Jan 31, 2013, 04:13 PM
jcdfrd's Avatar
be sure to have great cooling to the esc as it will run hotter with that setup
Jan 31, 2013, 04:22 PM
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4stripes's Avatar
I'll keep that in mind. The 100A ESC should easily handle operating at less than 50A, but it will still have decent cooling.
Jan 31, 2013, 04:47 PM
The best in EDF since 2005
Extreme_RC's Avatar
Originally Posted by alexandermh
Are you using the same housing for the 12 blade unit as you are for the 10 blade unit? My recollection was that the 12 blade unit was a bit bigger?
Yes, I am skimming the rotors 0.75mm radius as they are an almost interference fit into my housing. You "could" install then run slowly to clearance your rotor if you were so inclined LOL, also the fact the front section of my housing unscrews means you could assemble then run your fan slowly and sand it down that 0.75 then screw the front on. Of course I do not recommend anything that may endanger the user which is why the fans are available ready to use
Jan 31, 2013, 05:27 PM
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evo101's Avatar
wow 12 blade 70mm fans now thats a good idea Mark i bet these will sound better again!

Originally Posted by Extreme_RC
Well I have been able to run all my new CS12 combos now thanks to you guys ordering them I havent been able to thrust stand 2 of the combos but did take all the readings off the fans during final balancing and power runs.

Going by the thrust vs RPM of the CS12 2W25 combo I have on the stand right now it looks like the CS12 rotor produces a bit more thrust at the same RPM as the CS10 rotor.

My CS12 2W30 combo is running at 1645w which is 20w different to the CS10, rpm is up 600 so I will get that setup onto the stand today to get a thrust reading.
The mild 6s CS12 with 3W25 is pulling the same amps and watts as the CS10 does, RPM is very close too, I will thrust test this one after doing the hot 6s combo.

All the new combos are HERE
Jan 31, 2013, 05:45 PM
jcdfrd's Avatar
ya....where does he come up with all these great idea's
Jan 31, 2013, 10:41 PM
Registered User
Originally Posted by mopetista
Those are silly pricings.
Jan 31, 2013, 11:22 PM
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4stripes's Avatar
Adapter woes....
I have 2 ten blade 4mm adapters that were good.
I have 4 twelve blade 4mm adapters that are not true.
All fans ordered this winter at the same time.
It seems quality was better with the ten blade adapters. If my 3mm adapters can't be bored to 4mm, I will be looking for 2 good adapters. Not the first time CS has had quality control issues.
Feb 02, 2013, 07:00 AM
Registered User
I have two 12bl and the adaptors on those were good.
I made up my new balancer today.... have to find the pics....

I decided to Static balance the fans TWO ways now.....
1) Just the rotor
2) The complete shaft adaptor, rotor, nut.

I don't have an 8mm (or whatever it is) motor shaft to use for the rotor alone for now. This will be a 60mm length shaft with pointed ends put onto it.

The complete unit balancer is done by using a 'pointed 3mm bolt' for the front end of the shaft adaptor, and a "pointed 4mm motor shaft" for the motor end of the adaptor shaft.
Balanced between an adjustable magnetic balancer - made up from bits and pieces around the place.... A CS10 adaptor shaft, with a magnet CA'ed onto its end, for the 'adjuster' end. The fixed magnet end actually has two magnets, one on the outside face of the vertical stand and it 'joins in' with the inner side one to create a stronger magnetic force total.

The 3mm bolt end has a nut CA'ed onto it to increase the metal volume near its pointed tip - for more magnetic 'strength'. (same for the 4mm CS12 front end pointed bolt, but two nuts on that due to its heavy weight)
This thing spins a LONG time!! As good as zero friction... TOO GOOD!!
So you can increase friction by bringing the adjustable magnet end in to just touch the tip on that end... lightly.

I found that if I turn the rotor to a new position on the shaft adaptor, it can make the rotor end up not spinning true!! If you watch the rotor hub, it can be dead true in rotation... but rotate it on the shaft adaptor and test it again and it can end up not quite dead true anymore!!
This is also why the 3mm pointed bolt end is very short - to keep any spinner bolt hole 'error' out of the equation as much as possible.
You can also, of course, spin up the adaptor alone and test its balance... and also to watch/check that it spins true (this one did).

I made up bits for the CS10/12 and the CS12-90. It was planned in design to be able to fit both fan types. (or any 90mm really anyway - which I have some 11 blade "Viper" 90mm's coming to test)
For the CS12 shaft adaptor I have found they can be a fraction heavier to one side.... so for the testing one I filed a bit off the main large portion of the 'ring' end to get that truer. BUT you also have to check it spinning to be sure it is all physically true, as the spinner bolt hole can be a micron off centre/straight too!!

Last edited by PeterVRC; Feb 02, 2013 at 07:20 AM.
Feb 02, 2013, 07:46 AM
Gravity impaired
jrjr's Avatar
I finally got the motor for my CS12. Has anyone ever used the cell phone method for balancing the assembled motor/fan unit?

Or maybe the laser pointer method?
How to balance a brushless motor (1 min 10 sec)
Feb 02, 2013, 10:44 AM
Registered User
erh7771's Avatar
Originally Posted by jrjr
I finally got the motor for my CS12. Has anyone ever used the cell phone method for balancing the assembled motor/fan unit?

Or maybe the laser pointer method?
Look up clock method on YT...

Cell phone method = more precise way of clock method.

Looks like rotors are coming out of the mold pretty balanced for the most part so its a matter of getting the whole assembly balanced
Feb 02, 2013, 03:25 PM
jcdfrd's Avatar
there is also another precision parts already trued and balanced for you.....all you need to do is proper assembly

new product offerings from Tamjets

cs 70/12blade stock housing, which are a great replacement for guys using the stock 10 blade housings.
two plane dynamic balanced 70/12 rotors
precision alloy spinner and shaft adapters 4mm,5mm in sets or separate as needed
Feb 02, 2013, 03:43 PM
Registered User
Peter, here is a hint...

If you static balance the fan firsts, then when you go to do your dynamic balance, your added weight will mess up the 2 plane balance. I hope you understood that, what I am trying to say is, if your going to dynamic balance beter start with no added weight.

and when you dynamic balance move your weight from the back of the rotor to the front, And on anothere note, I use an iphone 4S to do my balancing and my jig will register 0.10g
I dont know if an android based jig will be the same.
Feb 02, 2013, 07:47 PM
Registered User
Yeah, I am sure there are all kinds of interactions... most we could not even measure. Even individual fan blade difference will affect 'balance' via aerodynamics (any chip, plus you can see there imperfect moulding/cleaning-up too). So a fan could be perfectly balanced physically but not aerodynamically.

I just add the weight mid hub.... half way down into the 'cells' there.
Feb 02, 2013, 07:49 PM
Registered User
jrjr, I would do the motor alone first. I was going to make up a laser system like that one you show, but I will do it via running just the motor in the housing with the android phone balancing setup for that.
That laser setup idea is too rough to use for total fan balancing, you wouldn't see fine enough detail. (but still better than none I guess!)

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