Anyone Running 4S with their 450?

[jent]

Originally Posted by dwdw910

Do you know where I can get a 9 or 10 tooth with slant gear?? I've looked quite a bit...

The other option is to go to a straight gear. With my 500 build, going to 8s, I wont be able to use the slant gear because I can't find a pinion that would fit it and give a good head speed. I have never used a slant gear, but I know they are supposed to be stronger and quieter (although risk putting lateral forces on the motor bearing).

With my 500 build I plan to replace the main gear with a straight gear so that I can get the correct gearing, and recognize it will be louder. You could do the same thing, AFAIK you only need to replace the pinion and the main gear.

[kiwianaBrad]

I had been running 3s for about 2 years on a sportv2 then purchased a nano tech 1800 4s pack and as i spun up, it felt more powerful but was jus getting to takeoff speed and boom! Found out late after the crash that the tail kicked around due to servo disconnecting from gyro. Of all the crashes ive had, it took out the canopy and nailed the battery(threw it from he heli)
So far my 4s experience hasnt existed yet lol but i have another on order!

[nameci]

Originally Posted by syncnzflying

I had been running 3s for about 2 years on a sportv2 then purchased a nano tech 1800 4s pack and as i spun up, it felt more powerful but was jus getting to takeoff speed and boom! Found out late after the crash that the tail kicked around due to servo disconnecting from gyro. Of all the crashes ive had, it took out the canopy and nailed the battery(threw it from he heli)
So far my 4s experience hasnt existed yet lol but i have another on order!

Unless you govern the head speed(either via throttle curve, ESC, etc), you are getting 33% more head speed(11.1V versus 14.8 V) on same set up(same motor/same ESC/same pinion) by just changing 3S battery to 4S battery. It is good thing it was down before your head separated in pieces and shooting out blades.

[nameci]

Originally Posted by flint723

I recently had "you don't need decent c rating packs for 6s) myth corrected for me. A 25c 6s and 50c 3s do deliver the same power if they are the same capacity. But we can't use the same capacity 6s packs as 3s packs. A 25c 6s 1200mah batt can deliver 30a. A 50c 2400mah pack can deliver 120a. So to be equal, the 6s pack must also be 50c, so it can deliver 60a.

Of course we never draw that many amps. But the point is you still need a 35c minimum pack in a 6s 450. You don't want the pack to be operating near its c rating limit. Which it would be if you were using a 1200mah 25c 6s (30a) pack. I routinely pull 27-30a on my 6s 450.

Are you pulling 27A-30A continuously(average) or Peak/Burst?

[flint723]

Originally Posted by nameci

Are you pulling 27A-30A continuously(average) or Peak/Burst?

Burst. But I have the data logs to show that my 6s 30c (it's more like 25c) battery has terrible voltage drop, I saw 18.8v during the 25a spike. And I have logs that show my 6s 35c batts that don't drop below 21.6 when pulling 30a. Both batts have ~10 cycles.

[nameci]

IMHO, C ratings are abused by many of the low cost battery manufactures.
I don't buy Nanotech batteries anymore because of this reason. My well used 30C rated GenAce batteries are stronger and more powerful than new Nanotech which are rated as 45-90C. Make things worse, Nanotech puffed up after few cycles.

[dwdw910]

Originally Posted by flint723

China is the only place I know of for the 3.5mm shaft 10t helical. They're made by Tarot, and tarot-rc-heli.com has the 9 and 10t for 3.17mm shafts here in the U.S., but they don't list the 10t 3.5mm. Maybe worth a shot to ask them if they have it, since they have all the other Tarot pinions. I'm using my 9t on my 6s 450 pro w/ 2000kv motor. The main gear is standing up fine so far.

They have them on ebay too (from china). Just search "10t helical" I ordered mine off of Miracle Mart.

Awesome. Thanks so much.

I have enough faith in Tarot to buy the pinion. Align needs to get on the ball. They are on vacation over there...

Id rather control the headspeed with the pinion and just run a flat curve... thanks :-)

[RedOctobyr]

Originally Posted by flint723

Burst. But I have the data logs to show that my 6s 30c (it's more like 25c) battery has terrible voltage drop, I saw 18.8v during the 25a spike. And I have logs that show my 6s 35c batts that don't drop below 21.6 when pulling 30a. Both batts have ~10 cycles.

Interesting. I recall seeing a similar Ice-logged voltage during my big spikes (~30A). What brand/packs are you using for the 30C and 35C? Mine are the Gens Ace 30C 1200's.

Tempering my numbers is the fact that the later you are in the flight, the same current draw will of course result in sagging to a lower voltage. And I don't remember when this occurred in the flight, but it probably wasn't right after takeoff.

Just found a log that dropped to 18.9V (3.15V/cell). Flying 325mm blades, 14/150T gearing, 3000 RPM, 14 deg pitch, this was likely during continuous tic-tocs, from looking at the log. It was ~60 seconds into the flight, drawing 25A.

21.6V is 3.6V/cell. I am at ~3.78V/cell after landing, with no load, of course. So to only *drop* to 3.6V/cell would imply this was likely early in a flight? And/or those batteries kick ass

You don't happen to have a charger that shows internal resistance, do you? I don't have much to compare my IRs with.

Edit- for comparison, at the start of those tic-tocs, same pack, I pulled 31.8A, and dropped to 20.3V. After about 10 seconds of hamfistedly banging the sticks, I dropped to a min of 18.9V while pulling 25A. So it's difficult to draw clear conclusions from a single number, or moment in time.

[dwdw910]

I would eventually like to build a 6s helicopter... I think too much power is never enough.

Just for ecnomics and also for a challenge- I'd like to see what I can squeeze out of the stock electronics.

Im not too concerned about the Align Speed Control's BEC...

I have both the receipt and the manual where it clearly says it can handle 4s.

So if it blows up, I'll be taxing Align for that.

[ebonicrobot]

I thought when they say that they can handle 4S, that's with only 2 servos?

[flint723]

Originally Posted by RedOctobyr

Interesting. I recall seeing a similar Ice-logged voltage during my big spikes (~30A). What brand/packs are you using for the 30C and 35C? Mine are the Gens Ace 30C 1200's.

Tempering my numbers is the fact that the later you are in the flight, the same current draw will of course result in sagging to a lower voltage. And I don't remember when this occurred in the flight, but it probably wasn't right after takeoff.

Just found a log that dropped to 18.9V (3.15V/cell). Flying 325mm blades, 14/150T gearing, 3000 RPM, 14 deg pitch, this was likely during continuous tic-tocs, from looking at the log. It was ~60 seconds into the flight, drawing 25A.

21.6V is 3.6V/cell. I am at ~3.78V/cell after landing, with no load, of course. So to only *drop* to 3.6V/cell would imply this was likely early in a flight? And/or those batteries kick ass

You don't happen to have a charger that shows internal resistance, do you? I don't have much to compare my IRs with.

My packs are a 1200mah 30c Tiger(?) pack and (2) 1300mah 35c nanotechs. The 18.6v and the 21.6v were just the "min" number that shows up in the castle log, so that would be the lowest anywhere on the graph. I am not doing long flights however. 4:30 I believe for both. Both graphs below show 22.8v resting at the end of the graph. There are multiple flights showing the same results as these, I have 4 flights for each type of battery.

IR's are averaging ~6.5 on the 1200 30c and ~5.5 on the 1300 35c. According to PL6.

[RedOctobyr]

Thanks for the extra details BTW I added some additional details to the bottom of my post, above, with another voltage/current comparison point from the same flight.

This is the log from that flight. Minimum voltage was 18.9V, max current was 31.8A, but those weren't at the same time. All that stuff happened in the ~45-55 second timeframe. I pulled a max of 644 watts during the flight.

The IR's the PL6 shows, I presume (hope) those are per-cell, not total? My iCharger shows 8-10 mOhms/cell for this pack, the last time I checked it by itself (when I have a bunch connected in parallel the measured resistance drops).

[nameci]

Don't bother with using governor on Align ESC. It does not work and will cause tail wags and wobbles.

[flint723]

Originally Posted by RedOctobyr

Thanks for the extra details BTW I added some additional details to the bottom of my post, above, with another voltage/current comparison point from the same flight.

This is the log from that flight. Minimum voltage was 18.9V, max current was 31.8A, but those weren't at the same time. All that stuff happened in the ~45-55 second timeframe. I pulled a max of 644 watts during the flight.

The IR's the PL6 shows, I presume (hope) those are per-cell, not total? My iCharger shows 8-10 mOhms/cell for this pack, the last time I checked it by itself (when I have a bunch connected in parallel the measured resistance drops).

Yeah IR's are per cell. They may go down a bit more as I use the packs more. That's one nice thing about the PL6, when you parallel charge you put in how many packs are on, and it changes the IR to be what it would be if you had one pack on.

[kiwianaBrad]

yea I just had my throttle curve straight 100% flat using 3s and didnt change it so maybe I didnt notice the hugh power increase and stuffed it!

[RiazP]

Comming in very late here, but some really good comments from some experienced pilots. Regarding 4s batts, do volts still do th 2200 35c 4s? They are great on the 2221-8

[RiazP]

Have a look at my signature, along with voltz 2200 4s 35c it rocks for 6:20 on an 11t pinion and goved to 3200, it's awesome, building a warpy on 6s though

[dwdw910]

Originally Posted by ebonicrobot

I thought when they say that they can handle 4S, that's with only 2 servos?

I looked into this... and on other forums- it is said there is a technicality with Aligns rating.

Indeed, the BEC is rated for 4s on two or three servos... not good for a helicopter.

So... all is not lost.. because now I have a valid excuse/reason to buy

ICE LITE 50

Align MX 450 1800kv

The reason I wanted to try conserving on 4s... is that I maintain two helicopters at all times. So whatever parts I buy, I have to buy two sets. This 6s conversion is gonna be a little pricey.

And some nice 22.2V batteries.

Thunder Power hasnt even made a good 6s battery yet? They need to hurry up. I like their batteries becasue they are usually so compact.

[RedOctobyr]

I think the Ice Lite 50 would be a nice upgrade. It has several advantages over the Align beyond simply the ability *really* handle 4S/6S. But it's admittedly more expensive.

If you want to avoid that, you could get an external BEC, and offload the BEC work from the Align's internal BEC.

The Castle 10A BEC is supposed to be pretty decent, and is $20. There are other cheaper options as well. I used a little Turnigy BEC for a while, $4, which worked fine for me on 3S. It's rated for 3A/5A, can handle up to 5S, I think. I used it with some fairly high-power servos (DS95-clones) before getting my Ice Lite. I get the impression that the max current output from BECs decreases as you increase the input voltage (it's that way for the Castle 10A, as well as the Align's internal BEC, etc).

Castle 10A BEC:
http://www.castlecreations.com/products/ccbec.html

Cheap Turnigy I used:
http://www.hobbyking.com/hobbyking/s...arehouse_.html

[dwdw910]

Good info.... thanks..

thats another option.. but at that rate-- with labor and parts...

I will just get 6s lol..

Money is not an issue... I just hate to be wasteful and not be happy with what I have.

For the big picture... I think that 6s would be the best bang for the buck.

Plus I do like to have power on tap.

Thanks for all your help in this thread... I definitely saved myself some money and troubles.


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