How many teeth in Swift 16 main gear?

[ghopper]

Thanks Chris,
I'm gonna take my time with this one. So far the motors I'm considering are the NEU, Orbit, and Z-Power. If anyone can think of some others I need to keep in mind, please feel free to chime in.

Dan

[RAV50]

I run this motor in both of my Swifts (16 & 550SE):

http://www.heli-world.com/detail.aspx?ID=9145

The 16 has over 100 flights with 5 cell 18.5V lipos packs doing some pretty demanding 3D geared for 1920 head speed and another about 150 flights with 6 cell 22.2V Lipo packs flying harder 3D - And the motor has been a trooper. That is why I got it also for my 550SE.

The 16 with the 5 cell uses this 55A controller:

http://www.heli-world.com/detail.aspx?ID=9021

The 550SE only has about 60 flights on it and uses this 80A controller (as did the 16 with the 6 cell configuration)

http://www.heli-world.com/detail.aspx?ID=8014

Even after a hard flight the motor and ESC's are always barely warm (almost body temp).

And setting them up has been "bundy" easy :-))

[ghopper]

Hi Rav,
I had looked at that motor, but if I go HV 8s, I'm gonna need a motor that is less than 800 KV. I'm looking for low amps and long flight times. Just circuits, stall turns, a few rolls and loops. With the 96 tooth main gear, it is gonna be hard to keep HS low without getting too small on the pinion. Do you like the century ESC, I was considering it's HV brother if I could find some folks that like how it performs?

Dan

[ghopper]

How does this look.

Dark Horse - Helicopter Power & Setup Calculator
Setup Report No. 1
=====================================
Generated: Thu, 10 Apr 2008 13:45:16 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: 1100
Tip speed MPH: 263.5
Max FF MPH: 79.0
Tip speed KMH: 424.0
Max FF KMH: 127.2
AUWeight g: 2150
Watts/kg of mass: 206.51
Disk loading kg/m²: 2.26


The weight is a pure guess on my part, maybe you guys can help me fine tune it if I can get comparable part weight for what I'm thinking. I dropped the main rotor diametor to 1100 (Is this correct for 500mm blades?) If I can get something close to this then maybe I can forgo HV at least for now. The TrueRc packs I'm looking at 3s 4000mah are 256 grams apiece. The Z30a 800KV motor weighs 277 g, so pretty much a wash with your NEU Chris.

Dan

[JustPlaneChris]

Dan, my Swift tips the scales at 6lbs 2oz (2778g) including non-stock landing gear (Hirobo Scedeau) which is slightly heavier than stock. I think 1160mm would be closer for the rotor diameter on 500's. Stock blades are 520mm. Other than that, you probably would have a nice flying setup there, and the motor could then handle HV later if you choose to do so.

[ghopper]

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]

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/m²: 2.22


Dan

[JustPlaneChris]

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]

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]

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]

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]

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

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.

[ghopper]

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]

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]

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]

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]

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]

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]

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]

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.