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CarbonXtreme . Midland Helicopters . HeliProz

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e-E-Flite Blade CP mCX CX 400-3D > Brushless motor and stock 4in1 works!
 
 
stealth916
Veteran
Location: Rocklin, CA

Here is a place in the UK to order the Kyosho 7T pinion for those who can't wait for me to get one & try it. These guys can get it faster too, I think:

Alan's Model Shop [sales@alansmodels.com]

Sample Quote w/shipping to USA:

AZW002-07 5.75 GBP
Airmail post 1.35 GBP

Total 7.10 GBP

This pic and the knowledge that others have used it in micro heli apps, and that it is .5 modulus and 2.3mm shaft size, is all we have to go on until someone here gets it in hand.




Knowing Kyosho - this part wont be available much longer...

P.S. - this pinion was originally for the Kyosho @12 RC car.
12-14-2005 Over year old.
 
 
FlyrEric
Senior Heliman
Location: Gulf Coast FL

Finally got my brushless seup working today thanks to all of the posts on here and some encouragement from BladeWrecker.
Final setup follows:
HiMaxx 4100 8t Pinion
CC Phx10 ESC
3s 1200mah LiPos
DD Tail
Stock TX/RX
Only had to tweak the proportion mixing a little but it seems to fly great. Of course its raining today so I can't take it out and really get on it, but the garage testing has been good.
12-17-2005 Over year old.
 
 
Hughes500E
Heliman
Location: Armstrong BC Canada

Very nice, I share the exact !
I just finished setting mine up as well and flew it in the livingroom
My setup is a Razor V2 Heli at 4300Kv
8 tooth pinion
25 Amp CC ESC (I had it)
2 cell 830 Apogee
stock flatty's
DD tail
I also fly with my 8U super. Never had to adjust programming in the Tx, I can hover in a 3 ft square no prob, very stable but, I have glitching, the ESC is on top of the GWS RX and I also installed a lightena (base loaded)
Too many changes at once LOL......... going to try and move the ESC first!
I think I'm going to like this

12-17-2005 Over year old.
 
 
FlyrEric
Senior Heliman
Location: Gulf Coast FL

I mounted my ESC under the 4in1 on top of the battery tray, no glitching yet. If it starts I'll try and put it elsewhere, I'm sure someone on here has already figured this one out, just a matter of reading.
12-18-2005 Over year old.
 
 
Hughes500E
Heliman
Location: Armstrong BC Canada

Success, I moved the ESC to the other side and the glitching stopped.
12-18-2005 Over year old.
 
 
kahunadad
Heliman
Location: Goodyear, AZ

Can anyone answer me this question? I am running an E-Flight (370 / 54kv) Brushless and the 10t that comes with it and the stock batteries. I have the 3s thunder power lipos but have not used them yet..what is the difference and why is everyone trying to go to a lower pinion???? Wouldn't head speed be greatly reduced by doing this? My 370 seems to give me great head speed or am I imagining it? I am new so this is a stoopid question to some but I bet there are others who wnat to know also....Can anyone explain this to a newbie?
12-19-2005 Over year old.
 
 
FlyrEric
Senior Heliman
Location: Gulf Coast FL

A brushless on stock batteries? What kind of flight time you getting eith that?
12-19-2005 Over year old.
 
 
stealth916
Veteran
Location: Rocklin, CA

The stock 9.6v NiMh can probably only provide 9.2v if lucky under load. So your head speed is around 2800RPM assuming your motor does 4300kv under load.

My opinion - a 5400kv motor on 3s lipo with 10T is out of control.

If we assume the motor is only giving 80% of 5400kv under load, or 4300kv - the math is:

(11.1 x 4300) / (140 / 10) = 3400 RPM Rotor.

Insane. Totally insane :-)

We have already discussed that stock is probably about 1700, Sport should be 1900-2200, and hard 3D in the hands of a Pro should be 2400 - 2600.

So to answer your question - why a smaller pinion. Let's say in your example, we use a 7T pinion instead of 10T - here is the math:

(11.1 x 4300) / (140 / 7) = 2385 RPM Rotor

The smaller the pinion - the lower the final speed and the more torque you'll have.

You could also try using 2s lipo and 10T pinion:
http://rantblogger.blogspot.com
(7.4 x 4300) / (140 / 10) = 2270 RPM Rotor

or 2s and 9T pinion:

(7.4 x 4300) / (140 / 9) = 2045 RPM Rotor
12-19-2005 Over year old.
 
 
akerkhof
Senior Heliman
Location: Indianapolis, IN

As someone who has experienced a HB with a measured 3000 RPM headspeed, I'd like to echo Stealth's assertion that those speeds are out of control. This was a 3s lipo mated to a 3600kv motor with a 9T pinion. I really need to go down to 8T, but for now I've capped my throttle at 75% in software. I don't know that you'd be approaching the structural limits of the head, but I would say that if you touched anything with your blades going that fast, they would vaporize along with your head assembly, main gear, and who knows what else. Before that happens, you'd enjoy a collective twitchier than a crack head swearing off the rock.

Not only that, but the stock tail had trouble holding my 2400RPM setup. The DD tail does nicely. But if you're over 3200 RPM, would it be capable of holding reliably? I just don't think it would be a machine that would be fun to fly. Are you actually flying this setup now, or just contemplating it? If the former, that is wild.


-- Aron in Indiana -- http://www.neolith.org/cp2 -- Honeybee CP2 Resources
12-19-2005 Over year old.
HOMEPAGE  
 
 
kahunadad
Heliman
Location: Goodyear, AZ

stealth916 & akerkhof this is exactly the kind of information I was looking for. To answer your questions.....

Yes I am running this setup currently. My flight times are not important to me at this point so I am not concerned about that. I am running the stock batteries right now. I wanted to know what the smaller pinion did and you have explained that for me...I have a futaba 9c heli radio and have the throttle limited to about 70%. I am getting an 8 tooth pinion to try and if need be a 7. Believe it or not the heli flys pretty darn good for the skills that I posess (read not much). I also have had absolutely no issues with the tail motors..I installed the Aluminum frame kit and the dual tail motors...they are wonderful and really plant the tail perfectly...My main reason for doing this is to prove I could...everything works great and I have had no trouble with the 4-1 or anything else...maybe I'm Lucky????
12-19-2005 Over year old.
 
 
akerkhof
Senior Heliman
Location: Indianapolis, IN

Yeah, if you've got your throttle toned down then no worries. I want to move away from that because I've heard its more efficient (and better for the ESC) to have the throttle run wide open and not artificially limit it. I don't know if that's true, but I figure I'll find out.


-- Aron in Indiana -- http://www.neolith.org/cp2 -- Honeybee CP2 Resources
12-19-2005 Over year old.
HOMEPAGE  
 
 
Riverman
Senior Heliman
Location: Peace River, Alberta

I'd really like to know the pros and cons of limiting the power output at the ESC too. Reading this thread and the headspeed management issues people are having has left me wondering why people don't just modify their throttle curve for less peak power. I don't have a computer radio yet (one on order) so I expect there is perfectly logical explanation for my question, I just haven't been able to tinker with it myself.
Anyone want to point me in the right direction?

Regards
12-19-2005 Over year old.
 
 
FlyrEric
Senior Heliman
Location: Gulf Coast FL

My opinion (and its only an opinion) is that if you're limiting power, head speed or anything else via software then your mechanics are all screwed up. You need to make sure the your heli/airplane/car/whatever is mechanically correct before you operate it. Masking problems or limitations with a computer (or a computer radio) is an invitation to disaster.
Simple fix...get a smaller motor or a different pinion (this I have done) and I have no problems running the stock TX/RX.
Computers and computer controlled devices fail, in which case poor mechanical setup will rear its ugly head and make a bad situation worse.
My opinion (Again, only an opinion) get your mechanical setup right and the rest is gravy!
12-20-2005 Over year old.
 
 
FlyrEric
Senior Heliman
Location: Gulf Coast FL

Stealth916..
Doing the math I calculate my head speed somewhere between 2080 and 2721 with the following setup:
HiMaxx 4100 8t
11.1 3s lipos
The low number uses the 80% rule, the high number is max power. Not having a tach or anything I would guess I average in the middle of that depending on how much I demand from the motor.
3400 is off the scale! I tried spinning up one day without blades as a demo for a newbie (just to show him the dynamics of the rotor disk). Well, I got a little cocky and wound up slinging a flybar paddle...no injuries to people but I did dent some drywall. You are correct that too much head speed is a bad thing!
12-20-2005 Over year old.
 
 
stealth916
Veteran
Location: Rocklin, CA

Limiting power has several effects - all mostly negative. It is very in-efficient. It will also probably make everything much hotter than it otherwise would be - that means hotter motor, battery, esc.

I am also of the opinion that setting the geartrain up mechanically, assuming near max power from the motor, is better than running reduced throttle. That is why I am waiting for the Kyosho 7T pinion before I try 3s lipo with the 4100kv motor.

The motors run best at 80%-100% throttle, and that is where I'd like my idle up curve to fall...
12-20-2005 Over year old.
 
 
lowpass5
Heliman
Location: Phoenix AZ

Head Speed

Interesting....

I'm running HB CP2 with Razor RZH2 motor ( 4275 Kv) , 9t, PHX 10, DD GWS tail, CSM 200 HLG, GWS 6N Rx on 3s 1200s.

I'm flying it with my JR 10sx with -4, +10 normal and -10, +10 at idle up. My throttle curve is linear to midpoint (75%) and 100% full. Idle up throttle is 75% mid, 100% at the ends.

I don't beleive I'm getting anywhere near the headspeeds you guys are quoting. I'm thinking it's somewhere in the 1200 range for hover. This setup has tons of power, but headspeed is nowhere near what I was expecting. It easily out accelerates my buddies Trex with JGF 450TH motor. He's running 2400 RPM and it is way faster than mine

I ran a Himax 2015-4100 for a short period and razor is way more potent and has higher head speed.

The razor seems about 50% higher head speed that with the stock motor. What am I missing?
12-21-2005 Over year old.
 
 
stealth916
Veteran
Location: Rocklin, CA

lowpass - maybe your CC10 isn't setup to drive the Razor properly (timing?) and it isn't getting full power. I have seen this happen to a few Trex flyers. Maybe check the timing settings and/or firmware version? It could be that it is just a bad motor/ESC combo but someone should be able to verify that. Some brushless ESC and motor combos don't work so well together.
12-21-2005 Over year old.
 
 
lowpass5
Heliman
Location: Phoenix AZ

Headspeed

Thanks Stealth, I don't think it's that. I pulled the 2015 and PHX 10 off my foamy to start with. The foamy would hover at 1/2 throttle all day so I know the set up was right.

I'm currious about the calculation everyone is doing. Isn't the KV rating for no load speed? Seems like it should be a lot less under load no?

Maybe I'm really getting more speed than I think. Maybe I should be doubling the 1200 optical tach reading. It seems a lot slower than my friends trex though... I tached him at 2300 today by running the tach at 1150. It only goes to 2000RPM.

Does anyone know what the stock brushed HB headspeed is at hover?

Thanks
12-21-2005 Over year old.
 
 
stealth916
Veteran
Location: Rocklin, CA

Yeah - perhaps your tach is wacky. 1200 sounds very low, too low to fly even. I use 80% of unloaded Kv rating as a rough estimate of the Kv rating under load for the brushless motor.

I tached my heli with stock motor and 9T pinion on 3s at 1800RPM on the ground in idle up at zero pitch. I figure it is about 1600-1700 in hover.
12-21-2005 Over year old.
 
 
Dr.Ben
Elite Veteran
Location: Richmond, VA, USA

I seriously doubt you're down at 1200 rpm. Down that low, the CP/HB2's have a lovely habit of just rolling over on the ground regardless of what you do with the cyclics. I'm thinking you need to do some tachometer reassessment.

Ben Minor
12-21-2005 Over year old.
 
 
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e-E-Flite Blade CP mCX CX 400-3D > Brushless motor and stock 4in1 works!
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