10S too much for 550 gearing?

[ukgroucho]

I'm looking at building a 550. I confess to being a 'higher voltage' freak - not simply to get ballistic performance but also because I think HV setups run more efficiently and give packs an easier time.

Sooo I started thinking about building a Hurricane and was musing over going 8S using pairs of 2200MaH 4S packs. United Hobbies have some low cost 20 - 30C units which would fit the bill quite nicely. But they ALSO have 2300MaH 5S 20 - 30C units which would also work out. This would give similar 'capacity' to a 6S 4000MaH pack but should be more efficient.

What I'm struggling with is understanding what the 'limits' are on gearing for the 550... what pinions and gears are available. Bottom line is I'm not sure what Kv motor would 'work' on 10S given the available gearing - or if a suitable motor is available.

Does anyone have any guidance?

[kgfly]

I think that if you get the after-market 61t/0.6M main gear then you have access to a much wider range of pinions. Look here: http://www.readyheli.com/Revco_Perfect_Circle_0_6M_CNC_Machines_1st_Gear_Ga _p/pc-5068.htm

This is a 0.6 module main so I believe you can use any of the 0.6 module/5mm-bore pinions from 18t to 26t.

You can use the Hurricane 550 headspeed calculator from here: http://www.readyheli.com/Online_Headspeed_Calculator_s/81.htm

For example:

Spur (Main) Gear Teeth: 61
Pinion: 18
# of Cells: 10
Motor Kv: 800
Headspeed = approx 2600rpm

Motors around 43mm and 250-350g
You could perhaps use a Z30A-800 (800kv) 43mm, 280g, $105 but I imagine you would have to be careful about stripping the main gear with such a powerful setup. I think you really would be pushing it and an 8s setup would probably be more sane. With an 800kv motor on 8s you could play around with pinions in the 18t-23t range to get your desired HS.

Kontronic Tango 45-06 (640kv) 45mm, 300g, $270 seems would be a good choice for 10s with lots of flexibility in pinion choice almost right across the 18t-26t range.

With some hunting you might find some other 8s or 10s combinations that suit you better..

These motors are probably too big or heavy
The Z50A-600 (585kv) or Z50--780 (780kv) are both around 49mm, 350g and around $125.

The Neu 1915H/1Y (685kv) is 50mm, 445g and around $270. This could be an excellent 10s choice on 18t-22t or 8s on 20t-26t

[ukgroucho]

Thanks Kenneth.

Yes, it's hard to work out what to do. The HV route is very attractive and 10S is really not much more cost than 8S... if you're getting the ESC and motor to cope with HV then the pack prices are not much more.

If I were going 8S then I was thinking about the Neu 1515/2Y 1100Kv unit. 40mmx69mm and 340g or thereabouts. Pricey though....

I thought the RevCo gear was 68 teeth not 61...?

[kgfly]

Oops! My mistake, sorry. The 61t Revco gear is a replacement for the tail drive gear. You are right, the main gear that couples to the motor is 68t.

I think you would want the heli version of that motor (finned case and integral fan): 1515H/2Y (1100kv), 40mm, 385g, $299 (ouch!).

A cheaper alternative with a good reputation would be the Z30A-1100 (1110kv), 43mmx61mm, 280g, $105. That saves you 105g and $195 which pays for the HV ESC :) However I wonder if the Z30A-800 would be a better choice for 8s since it would give you more flexibility to choose a range of pinions ? It depends what headspeed range you would like to have available. With an 1100kv motor on 8s an 18t pinion you should get around 2600rpm. I think that is pretty high for an H550. You could use throttle curves to tame it, with 85% giving about 2200rpm but lower efficiency. With an 800kv motor you could select pinions across the range 20t to 26t to find the right operating band.

[mbigby2]

I don't think you'd be disappointed w/ the z30-800 and 2x4S2500 flight power packs. I run this, and while I'm not a very accomplished heli pilot, you'd have to be daft not to see the power brought to bear for about 12 amps in a hover. Climbouts at 2300 RPM are w/ 12 degrees of pitch are shocking. W/ the revco gears (68T primary) my end max headspeed is approximately 100X the pinion. 23 --> 2350, etc. The main problem I have is that sometimes I hose the throttle settings in my ESC and then the slow start (or lack thereof) eats my primary gear.

BTW, I tried a 966 kV Neu motor. I got it to fit w/ the 61T main gear serving as a primary gear. There are pix if you search on my posts. Motor's great, but I don't know if it will fit if you use the RevCo gears. They bring the placement of the motor in (smaller diameter than the 61T main gear). This will increase the clearance problems. I'm virtually certain that any heli version of a Neu 19XX motor is an exercise in futility, since the shroud will add even further clearance issues...

[kgfly]

z30-800 and 2x4S2500
What flight times do you get ?

The main problem I have is that sometimes I hose the throttle settings in my ESC
What ESC and do you know what causes the problem ?

[ukgroucho]

Useful info from mbigby2 ... thanks.

Where is a good source for the Z-power motors?

[kgfly]

www.tppacks.com
www.wattsuprc.com.au

[Happy|Harry]

here's a little doc i made up a while ago that lists all of the available gearing ratios for the 550

groucho i'm thinking along the same lines as you but i'm planning for being able to swap between 9S li and 10S A123, PH45 HV for the ESC and a Scorpion motor (a 3032 just now and then a 4020 if i'm not happy with the 1500W 3032) this works out to be a reasonable cost for a HV setup :)

phil

[ukgroucho]

Phil,

Nice data ... thanks. Where do the 12 -17t pinions come from (mod 0.6)? I've only seen those down to 18t.

Certainly a 14t would provide a nice HS for an 1100Kv motor.

I looked at the Scorpion motors. They look good... but the 30 series only seems to be 1200watts.. that's a little lightweight if you want serious performance. A 40 series SOUNDS Like a better fit but I could not find any data - just some mention that they were coming along.

[kgfly]

Scorpion seem to have an Interesting range of motors. I couldn't find specifications on max rpm or max voltage but the sample prop data seemed be baised towards 3s/4s setups and their range of ESCs are only 2s-4s rated so my guess is these motors are not rated for 8s/10s operation. They also do not have integrated fans although do claim that the slanted cooling holes act to draw air through the motor. I would be concerned about them running too hot in a heli even though they are rated to 180C.

[red_z06]

We use Gaui 1100kv motor with 6s3300 and 14-15T pinion on 515mm blade with head speed of 26-2700rpm.

My first choice on hv setup would be to go with 9s 2070-2200 as these are multiples of 3 or 3 available 3s packs. The best way to use 3s packs is to group them in similar cycles so they perform more evenly.

The quick and dirty way to calculate for the stock gearing would be to multiply kv * #cell.
In our case that number is 1100*6 or 6600. For 9s setup, 6600/9 yields 733kv

Since there are 13-16T pinions available, 700-800kv motor would perform nicely without any mods. If you change the secondary gear from 42 to 61, it would allow you to use the stock 1100kv motor with 9s setup.

[Happy|Harry]

Phil,

Nice data ... thanks. Where do the 12 -17t pinions come from (mod 0.6)? I've only seen those down to 18t.

Certainly a 14t would provide a nice HS for an 1100Kv motor.

I looked at the Scorpion motors. They look good... but the 30 series only seems to be 1200watts.. that's a little lightweight if you want serious performance. A 40 series SOUNDS Like a better fit but I could not find any data - just some mention that they were coming along.

for the 12-15T 0.6Mod pinions i am unsure about availablility (perhaps an email to RevCo could see some being made available for us?) but the 14T problem can be worked around by using the 61T 0.8Mod main gear as a primary (gaui or revco) and using the standard hurricane pinions.

the scorpion 3032 is a 1200W continuous motor, and 1500W bursts are well within it's reach with their N50EH rated magnets ;) there's some preliminary data on the 4020 in the scorpion thread here>> http://www.rcgroups.com/forums/showthread.php?t=681251 i think the 3032 wound for either 1000 or 1100Kv will be a great performer on the hurricane on 9S, but i'll know one way or the other soon enough, and if it's not good enough a 4020 will be put in it's place lol :D

phil

[Happy|Harry]

Scorpion seem to have an Interesting range of motors. I couldn't find specifications on max rpm or max voltage but the sample prop data seemed be baised towards 3s/4s setups and their range of ESCs are only 2s-4s rated so my guess is these motors are not rated for 8s/10s operation. They also do not have integrated fans although do claim that the slanted cooling holes act to draw air through the motor. I would be concerned about them running too hot in a heli even though they are rated to 180C.

the bearings in the motors are rated for 60,000rpm so i think they will be ok in a HV setup as at that rpm's with a 10 or 14 pole outrunner it's the ESC we have to worry about lol. the current range of esc's are only those that were first released with the smaller motors, there are some HV controllers, namely a 12S version with 60A, 120A and 180A models, also a 15S version with 100A, 150A and 200A models being released soon to use with the larger of the scorpion motor line :)

i hear you on the no fan problem and their slanted cooling holes do move some air but not enough imho, but i've spoke with lucien at innovative designs and he's informed me that there will be fans released for the scorpion motors similar to what model motors released for the axi's so that should solve that problem :thumbup:

phil

[ukgroucho]

Well I pulled the trigger and ordered the Hurricane Carbon Pro kit (CF frame) without the motor and ESC and with a separate complete CNC head.
Also ordered a Jazz 55-16-30 (OUCH) 10S capable with a 6 amp SBEC.

Now I need to decide on 8S or 10S and get a motor, pinions and packs ordered. Currently leaning towards the Z30 800 as I could use that on 8S or 10S

I'm gonna use the 821s that came with my DX7 - I'll order the larger wheels for them - but am undecided on a gyro. I can probably liberate a 401 from my brushless fixed pitch heli but I'd still need a suitable servoi for the tail. Or do I just spring for a 611?

[mbigby2]

What flight times do you get ?

See my post here: http://www.helifreak.com/showthread.php?t=42729. Note these times were for TP2200's. The FP2500's are better on a couple of dimensions...

What ESC and do you know what causes the problem ?

I'm using a Spin55. The spin's rock for aircraft, but the governor settings are hard to grok. It seems that if you start up w/ the throttle lever in the wrong place, you can reset the range on the throttle (which needs to be manually set to function properly). This can result in small stick movements making dramatic speed changes. The slow start as a whole sucks, IMO. Who knows maybe it's pilot error...

I'll probably go back to the Castle 45HV. I just liked the absence of a secondary BEC (and associated wires).

[ShuNut]

Reading this thread with high interest as i too am thinking of doing this kind of set up for this heli,
Main reason being cheep lipo packs.

Anyone know if this ESC is any good http://www.unitedhobbies.com/unitedhobbies/store/uh_viewItem.asp?idProduct=4691 ??? its very cheep so i know it could be junk but u never know.

ukgroucho, u went ahead and ordered it ! Nice. U gotta keep us updated on the build, in this thread or a new build thread.

For me i think ill try the Logictech -6100 gyro on what ever big heli i decide to get.

[ukgroucho]

So I'm going 10S... I've ordered United Hobbies 2300MaH 20-30C 5S packs.
Z30-800 motor, will try the 19t with Revco 68t 'motor' gear and 61t tail drive... should give a nice 2200-2300 sustained. I've also ordered 18t and 20t in case I need to adjust.

Once I get all the bits I'll either post a build thread or let folks know how it all pans out.

Decided to stick with a 401/9254 to keep weight and cost down. I'd love a 611 but I've dropped quite enough dosh into this bird already. Maybe when I build my Rotorworkz variant :) To go with my 3 Rotorworkz Trexes

[kgfly]

Excellent! We want details and photos please :) And once it's flying, FDR logs too ;)

[mbigby2]

Also ordered a Jazz 55-16-30 (OUCH) 10S capable with a 6 amp SBEC.

Just out of curiosity, is the Jazz 55 rated for 10S? I thought 8S was the limit...

[kgfly]

the bearings in the motors are rated for 60,000rpm so i think they will be ok in a HV setup as at that rpm's with a 10 or 14 pole outrunner it's the ESC we have to worry about lol. the current range of esc's are only those that were first released with the smaller motors, there are some HV controllers, namely a 12S version with 60A, 120A and 180A models, also a 15S version with 100A, 150A and 200A models being released soon to use with the larger of the scorpion motor line :)

i hear you on the no fan problem and their slanted cooling holes do move some air but not enough imho, but i've spoke with lucien at innovative designs and he's informed me that there will be fans released for the scorpion motors similar to what model motors released for the axi's so that should solve that problem :thumbup:

phil

FYI here is a response from Scorpion to my questions about max RPM and/or voltage/num cells, bottom line is work on 20,000rpm limit for the existing 30mm motors which for a 10s setup would mean 600kv or less:

> Hello,
>
> I cannot find any max RPM, max voltage or no. of lipo cells specifications
> for the Scorpion motors so it is hard to know if they will suit my needs.
> I am looking for 800-2000W motors for use in helicopters on 4s/6s/8s/10s
> lipo setups. Since the Scorpion ESCs are only 2s-4s my guess is these are
> low-rpm motors and only suited to 4s lipo max. Can you clarify if any of
> the 30mm (or the coming 40mm) motors can be run on 22-37V ?
>
> Thanks,
> Kenneth

Kenneth,

The 22mm motors can be spun up to over 35,000 RPM without any problems. The 30mm motors can run up to 20,000 RPM, and probably even higher, I just have not run one any faster than that.

I have run several of the 30mm motors on 5 and 6 cell batteries, and if you run one of the lower Kv models, you could easily go up to 8 cells and possibly even 10. For example, the 3032-12 motor has a Kv of 686, so if you ran it on 8 cells, or 28 volts, the no-load RPM would be 19,208 RPM.

I run a 3020 in my F-4 ParkJet on a 6-cell A123 pack, and it runs about 14,000 RPM on a 9x7 prop with no problems at all.

The new 40mm motors, which will be coming out in around 6-8 weeks, are designed to be run on 4-10 cells depending on the wind. Just so you know, Scorpion is working on a series of 35mm motors that will be used in Ducted Fan applications and 600 size Helis. These will be in the 1500-2500 watt range, so they should be perfect for your application. I am not sure of an exact release date yet, but it should be done before the end of the year.

Hopefully that answers your questions, if you have any more, just let me know.

Thanks!
Lucien Miller

[Happy|Harry]

FYI here is a response from Scorpion to my questions about max RPM and/or voltage/num cells, bottom line is work on 20,000rpm limit for the existing 30mm motors which for a 10s setup would mean 600kv or less:

ken lucien is mainly a plank guy, and he's not tested any of the larger motors in anger yet as he hasn't a powerfull enough ESC to do so. as for the max rpm's again i'll say that the bearings (2 x MR 95ZZ and 1 x MR 105ZZ) are rated for much more than 20,000rpm and also like i said previously it's the ESC that can be the limiting factor for high rpm's in outrunners.

phil

[ukgroucho]

mbigby2... 10S based on what the Kontronik web site states http://www.kontronik.com/index2e.htm

Of course I have to actually get hold of one... modelflight in Os where I buy my Jazzes don't have them yet. This could slow things up a bit. If they cannot get a clear ETA then I may have to swap to a 55-10-32 and external SBEC... more weight and wiring to clutter the build up.

Kenneth. ABSOLUTELY. First flights will have the Eagletree FDR onboard. I don't tend to leave it on any one rig for long but for testing out how a new build or configuration behaves or debugging it's the best.

Just gotta wait for post from 3 continents... The Jazz delay may be an issue.

Another question. Any thoughts on a LiPo alarm for 10S? Preferably with a loud beeper.

[kgfly]

ken lucien is mainly a plank guy, and he's not tested any of the larger motors in anger yet as he hasn't a powerfull enough ESC to do so. as for the max rpm's again i'll say that the bearings (2 x MR 95ZZ and 1 x MR 105ZZ) are rated for much more than 20,000rpm and also like i said previously it's the ESC that can be the limiting factor for high rpm's in outrunners.

phil
Thanks Phil. I agree that there can be an issue with ESC's being able to spin multipole outrunners at high speed. It is also great that the bearings are rated for 60,000rpm but that doesn't mean the rest of the motor will hold together at that speed. It only takes a little movement or distortion to cause imbalance and vibration which can then lead to either an electrical or mechanical failure. I am not saying anything bad about the Scorpion motors but until the manufacturer provides a suitable rating or does appropriate testing I would not take the risk. A 3032-1000kv motor on 10s will be spinning at over 35,000rpm, 75% more than the manufacturer has tested or approved, that's way too much for me to risk. I look forward to more test data from the the manufacturer on the 35mm and 40mm series which he says are designed for up to 10s.

[kgfly]

Another question. Any thoughts on a LiPo alarm for 10S? Preferably with a loud beeper.
Definitely, Efliernz right here on Helifreak:
http://www.helifreak.com/showpost.php?p=384253&postcount=13
http://efliernz.googlepages.com/home

His units are simple, compact and easy to use. I highly recommend them. Peter is great to deal with and will customise to suit your needs. For example he recently made a 3s-6s one for me with a dual-tone piezo (the beat frequency is even more penetrating) and a cluster of super-bright LEDs. The LED clusters are *very* visible even in strong sunlight and at a distance. IMO even the 92dB piezo can be hard to hear on a larger heli or at much distance so I am going for just the LED cluster on my next one.

I know Peter has made alarms from 2s up to 7s, not sure about 10s so send him a PM and ask.