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ghopper
04-10-2008, 10:37 AM
Hi Chris,
Kinda what I was thinking. I can search, but was your battery around 700 grams? I'm also thinking the Medusa Potencia 6v 3.5 amp bec (20 grams).

Dan

ghopper
04-10-2008, 10:46 AM
Chris NM,
I went back and it right here in this thread.....775....that gives me 263 grams lighter battery. I'll plug those numbers in and see what it shows.

Dark Horse - Helicopter Power & Setup Calculator
Setup Report No. 3
=====================================
Generated: Thu, 10 Apr 2008 14:45:23 UTC
=====================================
Motor RPM/V: 800
Main Gear: 96
Motor Pinion: 13
Gear ratio: 7.3846

Efficiency: 100 %
Motor RPM: 17760
Rotor RPM: 2405

Efficiency: 85 %
Motor RPM: 15096
Rotor RPM: 2044

Battery Pack: Six cell (6S) - 22.2 v
No. of cells: 6
Nominal Cell V: 3.7
Nominal Pack V: 22.2
Actual Pack V: 22.20
mAh capacity: 4000
Amps average: 20.00
Watts average: 444.00
Runtime avg.: 12.00

Rotor size mm: 1200
Tip speed MPH: 287.4
Max FF MPH: 86.2
Tip speed KMH: 462.5
Max FF KMH: 138.8
AUWeight g: 2515
Watts/kg of mass: 176.54
Disk loading kg/mē: 2.22


Dan

JustPlaneChris
04-10-2008, 11:15 AM
You can probably even drop down to a smaller pinion. 1800-1900 rpm is plenty for training and sport flying, and your batteries will thank you. :)

ghopper
04-10-2008, 11:34 AM
Chris,
I was gonna ask about that a bit later on the pinion. I'm not sure what all the DH calc is using to estimate the head speed. Is the say 85% effficiency combining motor as well as throttle or govener control? Eventually I'll probably pick up a tach to verify, haven't really felt the need for that yet. One other question, while looking at the kit and parts on century site, I noticed they no longer show the CNC motor block, have they changed the stock to make it better or is there something else I'm missing on what they have done?

Dan

JustPlaneChris
04-10-2008, 11:52 AM
As far as I know, the stock kit has the plastic motor mount (mine does). The only upgrade I did on mine other than the Hirobo landing gear (personal preference) is the CNC rotor hub. And I only did that because I knew I'd eventually be running 550s up around 2000 rpm and didn't really trust the plastic at that speed. For smaller blades and lower rpms, the Swift kit straight out of the box really doesn't need any upgrades to fly well. Refreshingly different, eh? :)

ghopper
04-10-2008, 12:03 PM
Chris,
Yep that is cool to get something that works well right out of the box. The flip side to that is that some of the issues are created by hot 3D fliers that need stiffer setups to begin with. My flights are gonna be mellow for a long time. Another quick question, are boom strikes gonna happen with these longer woodies if for instance say I put it down a little hard? I just did that on my rex using 335 woodies, I was like WT..... sheared carbon fibre tail boom and broke my blades amonst other things Still my fault for sure but that little rex is pretty twitchy it drops or rises with very little throttle input.

Dan

JustPlaneChris
04-10-2008, 01:47 PM
Dan, the dampening is pretty stiff on the Swift, so as long as you run the blades pretty tight in the grips I don't see a boom strike as very likely. That said, I haven't had any super-firm arrivals with my Swift (yet) so I may be totally full of :badair:

I find the Century head design to be a lot less twitchy when it comes to collective response compared to the Trex-style, making the Swift so smooth and easy to hover. In fact, my Dragonus has what looks like a tiny Swift head and it too is much smoother than a Trex. :D

ghopper
04-10-2008, 02:04 PM
Chris,
I understand what your saying, I'm still trying to fathom a 4 foot rotor disk. I've seen where some folks have put a dragonus head on their Trexs, so I may consider that after I get this puppy all together and hope it flies as well as I've seen some do it. Nothing will make the little Trex float thou. I'm getting geared up, getting my price list figured up and so far it's just at $400.00 with a gyro, tail rudder, batts and spare parts to add to that yet. I actually will probably ground the Trex and just use it's 401 for the gyro at first.

Dan

centuryman
04-12-2008, 12:37 AM
The swift only has one size main gear 96 tooth.
The swift 16,swift 550, and swift 620 all use 96 tooth.
and there are a 8,9,10,11,12,13,14 tooth pinions available.
Because of the smallness of the maingear it makes pinion changes big jumpd.Suck as 1 tooth differnce in pinion size equals about 250 headpeed.Thats a big jump or drop. And it really limits motor selection.It makes fine tuneing kind of dificult .You almost always have 2 choices, to much headspeed or not enough headspeed.
Don't get me wrong i love my 2 swifts and they are good helis, However i did just get Gohbee Phazor 600 witch is totaly awesome and it has 495 gear ratio combinations through the use of a duel stage drive system useing pulleys and a belt to the pinion witch engages the maingear.There are 15 primary pulleys available and33 secondary pulleys available and 4 lengths of belts.So basicly any motor you can phisicly fit in it can be geared to work properley.

ghopper
04-12-2008, 09:13 AM
Thanks centuryman,
I guess my next question would be, how efficient are goveners at filling in the headspeed gaps created by lack of gear ratios?

Dan

centuryman
04-12-2008, 01:50 PM
I've had 2 century 55/70 esc and fryed both of theme I now use castle pneniox 80, and 2 hv 85's and 2 thunder bird escs and they are much much much better then the century esc's as you just eluded to some escs goveners work better then others.The castle esc's are way under rated, so if it says 85 amps it can actully run 110 amps continous an so on.with that being said if you use a century esc go with there package deal. It is all desighned to work with each other and they do so fine.However if you whant to experiment with different motors and gear ratios and battery cell counts then by all means go with the castle hv85 esc.It's the bench mark witch every body'elses esc are compared to .With that being said yes if you have a good esc the govenert can make up for bad gearing. How ever the reason i went with this Gohbee phazor was because of all the gearing options and being able to tune the system to perfection. Because the problem with useing the govener to make up for improper gearing you run into lots of other problems such as you may have to pull more amps then ideal witch would mean you would need bigger and heaveir battery to pull thoes amps and now your heli is heavier and pulling even more amps.It can be a vicous cycle.or maybye you might overheat the motor and shorten its life.Or if you set the throttle to high to make up for low gearing now you won't have enough power left on top for pitch changes and that will cause a bog with a motor that has buccoo power but set to high on the throttle. I could go on forever. there is alot more to eletrics then most poeple think. But if you get right WOW do they have power.

ghopper
04-12-2008, 04:36 PM
Thanks Centuryman,
That was kinda what I was thinking the govener would do. I understand what your saying about how one thing can effect another and so on. I was considering the century hv esc they have now, but I think I'll go another route now.

Dan

RAV50
04-12-2008, 07:04 PM
I have had nothing but great experiences with the Century speed controllers. Between myself and a regular flying friend we have combined more then 700 flights on our two 55/70 speed controllers (I do understand that they may have had some problems with the BEC circuit in their initial ones) and we have over 450 flights between us using 6S packs through their 80A units - all the time they have performed flawlessly.

Unfortunately I cannot say the same of my experience with the CC85A unit, but as mine was one of their first units, maybe they have solved their problems also.

I also know of a number of others using them at the two fields I frequently fly at and they to have all been very happy with theirs.

Consequently, I plan to put one of the Century HV units in my 620E whenever I can get around to building it.

Jamesppp
04-12-2008, 07:09 PM
Hi ghopper,
I have a CC45HV ESC and after hovering for 8 minutes with a 5S 5000mah pack, that little ESC was almost ambient temp. I think that Greybird has the same ESC on 4S 10,000mah and JP Chris with10S A-123's so it is a very versitile piece. Im only at the hovering stage now and will never have the ability to fly hard 3D so Im all set. Im chomping at the bit to really fly this thing but but only hovering so far in the 3-1/2 weeks I have had it.I think in my case, this was the best choice heli for me.
I started in January with a pair of Lama 3's, in February I a got a pair of HoneyBee FP's and in March the Swift. I love it.

centuryman
04-12-2008, 10:19 PM
I have haerd the same from other people .I must have just got two bad units,and i wasn't even useing the built in bec.
However the main reason i like the castles and i must like them i have 6 of them. :) is the ajustability of them is almost infinite for fine tuneing the perfect setup they're tough to beat plus the castle link for programming it on your computer is awesome none of that counting beeps moveing sticks and then scewing up and starting over again.
I also have 11 or 12 (i loose count) of ther 6s 10 amp BEC's that work flawless and can also be programmed with your pc from 4.8 volts to 9.6 volts. and only $21.99.
Ijust figure for an extra 30 or 40 bucks you can have the best so why not.Theres places to cut cost but electronics is'nt where i do it. all it takes is one crash caused by a cheap component to pay for the best stuff and then some.I know I've been down that road.:(

ghopper
04-12-2008, 11:01 PM
Thanks for the replies guys,
I don't intend to skimp, just looking for good bang for buck. It appears most are using seperate BEC's. Is there a minimum amp for digital cyclic servos? I was looking at the Medusa potencia 3.5 amp. Any thoughts in that area?

Dan

centuryman
04-12-2008, 11:23 PM
I actully have a medusa on my swift and 3.5 amps should be fine for most digital srvos.
However i recently discovered those 10 amp castle bec for 22 bucks and have been outfitting the rest of my fleet with them.there only drw back is they're only good up to 6s.Witch is all that most people use. I have had no problems with either one but for the money i would go for the castle unit, the medusa i have is the 6volt model and isn't adjustable and it cost $46.00 and is only rated for 3.5 amps , but it can go up to 10s. the castle could run a set of 8717's or the like with no problems

ghopper
04-13-2008, 08:45 AM
Thanks centuryman,
I had not located that CC unit, but for 22 bucks it wouldn't be a deal breaker in the least. I'll see if I can find one.

Dan

centuryman
04-13-2008, 09:11 AM
Tower hobbies. I think ready heli has them to.:)

ghopper
04-13-2008, 10:29 AM
Hi Centuryman,
I was just there, pulled the trigger on a kit, cc80, and s9452 servo. I found the ccbec at helidirect. Guess I missed it at towerhobby. Now if I just decide on the powertrain, I'll about have all that I need.

Dan

centuryman
04-14-2008, 08:41 AM
GHOPPER
I am just finishing up my second swift 16 I put neu 1907 in this one and am running it on 8s. It should be insane.
However the century 600a plus motor works great on 6s. MY first swift 16 has that motor and it has good power and is running cool it has probobly 200 flights on it and still going strong.
for a 6s power system your going to whant a kv rateing of 1100 max if you could go lower that would be great.then you could run a larger pinion and the maingearwill hold up better when you start getting crazy with it.
Also castle makes a castle link for 22.99 from tower. this will allow you easier accsess to you esc tuneing .plus you can download updated programming as it becomes available, and i beleive ther are more options with the link.You'll need the link to program the ccbec anyways.

ghopper
04-14-2008, 09:03 AM
Thanks Centuryman,
I'm bouncing between running it as a 4s or a 6s system. I've been looking at the scorpion 1000 kv for this heli. I'm not sure it gives me enough headroom on 4s thou. Using the darkhorse advanced calc, a 14 tooth pinion gives 1835 headspeed. I was thinking of running about 1700 headspeed (I'm pretty much a beginner yet) I'm guessing that would be too close to run a govener as it wouldn't leave enough headroom. Of course for all I know I shouldn't even necessarily consider 1700 to begin with. Or as a beginner is there any benifit to using a govener?

Dan

kaan.gok
04-14-2008, 10:00 AM
I don't think you'll need a governor for beginning, especially for an electric heli. If geared optimal, the need of a governor on electric helis far less then nitros.
I'm running Thunder Tiger ripper motor (bought from infinity-hobby.com) on my Swift, it's another good option. It's almost the same motor as Century 600+, but 40 $ cheaper. I read somewhere that both motors are produced by z-power under contract.

ghopper
04-14-2008, 10:48 AM
Hi Kaan,
Thanks for the info, I'll check into that motor as well. The only thing I can think of that a govener might provide is a more stable hover possibly, as with a constant headspeed an adjustment on pitch is just that, pitch only and not both pitch and throttle increase. Is that a possibility? Since I've never used a govener, I may be talking out of turn here.

Dan

kaan.gok
04-14-2008, 11:02 AM
Well, your headspeed on hovering will be almost constant if you use a governor or not. :)
So governors do not produce a stable hover. Flybar weights, heavy paddles/blades, expo on the radio helps on that department.

The difference comes when you starting to do flips/loops/pitch pumps etc. The governor compansates for the difference in loading the rotor and tries to keep the rpm same for a constant feel on the helicopter. ESC's keep it up to a certain amount, most of the people use a flat 100% or 95% throttle curve or a very flat v curve on idle up modes. (for electrics), and the headspeed will be "constant enough". On nitros, you'll need to fine tune the curves because the response of a nitro system is different then electric system. There a governor really makes a difference.