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May 21, 2019, 08:11 PM
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Doug Simmons's Avatar
Quote:
Originally Posted by Andrew73
AS3X very good in high wind today, it even blew my cap off a few times but I was happy doing flight after flight no problem.

Only thing lacking with the Val is a bit more vertical, although I do use 2200 batteries and carry a 30g camera I guess...

Anyhow bought a Durafly EFXtra to go with it, should have a bit more oomph for big sky stuff.
If you'd like more thrust on tap, a lot more, the Leopard 3542 1080kv delivers:

RC motor demo: HeadsUpRC's Leopard 1080kv, WOAH (0 min 39 sec)


https://www.altitudehobbies.com/prod...airplane-motor

Though it's a tad heavier and longer, not a subtle substitution. The Leopard 3536 960kv with an 11x7 is pretty similar to the stock motor though you can push it much harder without it burning out, if inclined.

Clive I haven't run out of Valiance to discuss. This plane is becoming a platform for me, if that's the right word. I want to buy myself more distance in a night flight before struggling to stay oriented, when the lights get blurry it can be tricky to figure out which way is up before crashing. So I dug around the house and found some barbeque skewer long toothpick things, I glued on colored bulbs to the tip of two, put JSTs on them and the lights already on the wing, and for my next flight I can stab each into each wingtip and visually stretch my wingspan significantly. Maybe they won't fall off or short all the lights, will advise.
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May 22, 2019, 08:36 AM
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Doug Simmons's Avatar
Also Jim: Worth noting that my empirical data concludes as definitively as things get that there is an exponential correlation, causal, between modifying your Valiant in pretty much any way other than spraying on a couple thin coats of Minwax, dripping some Loctite on your screws or slapping on Timber wheels, and crashing it immediately. That motor for example, it's only thirty grams or so heavier than the stock motor, but that additional weight is pulling the nose down with even more leverage than the weight of the stock motor as it's sticking out several millimeters farther. So either you fly with messed up CG and compensate with trim and being on guard not to stall, or you add even more weight by taping some lead blocks to the tail, or somewhere in between, either way it becomes a different airplane, were you to limit your throttle range so that that motor tops out at roughly the thrust you'd get from the stock setup.

And when you disable that throttle limitation, suddenly full throttle is 680W instead of 270W, suddenly top speed is not 56mph but, I don't know, I kept crashing before I could measure it, let's say 68mph. That doesn't sound like a big difference, 12mph or whatever, but you might be forgetting the exponential increase of influence of air traveling faster over your control surfaces as you drag the plane beyond what would normally be its terminal velocity on a full throttle dive, and the air going by your elevator is much faster than the air over the other control surfaces not in the prop wash. You forget to dial down your lowest rates, gun the throttle, it pitches up more than you'd expect because of that messed up CG, you push the elevator to compensate, bam, faceplant. Or instead of using no gyro, or a gyro that lets you dial down the gains with a knob mid flight, you leave the AS3X correction aggression the way Horizon set it and the plane oscillates way too violently at higher speeds than they had tuned it to, you don't notice it's oscillating because you're flying so fast, and maybe the firewall rips off, the motor now a 130g 35mm artillery slug with blades of death attached. It will be too tempting to use more power than you would otherwise, so you'll slice your flight time in half, or even lower as the voltage drop from the extreme current will hit 3.2V/cell pretty quick and trip the LVC. So you use a bigger battery, you slap on enough sensors to turn the thing into a flying watt meter, your cameras etc, the thing looks like a Valiant but is anything but. You can no longer refer to the plane with feminine pronouns. That said, progress does often entail risk and destruction, and man wants to explore.

Anyway back to banging up the thrust for not that much money and with most of the above mitigated, the Leopard 3536 960kv, relatively cheap, if you sneak that motor onto Donnie's airplane without telling him and manage to get the cowl on (it doesn't quite fit), take off and hand him the transmitter, I doubt he'd know the difference. Drop in a beefy ESC and slap on a prop with a third blade, or just pop in a 2500 4S and at least a 40A ESC, and now you've got ass-hauling thrust that, while still very risky and counterproductive for most Valiant enthusiasts, if you have a switch that when flipped limits the throttle range so that full throttle spins an 11x7 at about 9500 rpm with a 1300 4S inside, that's roughly the same as a stock Valiant. Flip the switch and there's your crazy thrust where flying vertically doesn't seem much different than horizontally. The larger 1080kv, I don't recall if I dared to pop a 4S in for that. Sounds like a good way to rip off your entire tail, and it's hard to land safely without the tail.

That motor's pretty impressive actually even with 12V. Here's the Leopard 3536 960kv on a vertical run with a normal 1800 3S with extra weight from sensors and a camera. (The fisheye lens makes it look less vertical than it was.) I took off, pitched up immediately into vertical, and it sustained a vertical speed of roughly 20mph, hit the clouds in no time. Though the clouds were low that day, about 1100ft. Oh, that's also not courteous in a polite society, flying that high (with a modified airplane and not in the middle of nowhere), this was from my darker days a couple years ago.

E-flite Valiant: Extreme Thrust Powertrain Mod (0 min 49 sec)

Static thrust from just popping in a 4S in your basement and gunning it for a few seconds yields around 470W with nothing else changed, which is about 30A I think, possibly being choked by the ESC (I don't remember if I swapped in another, maybe the Timber or Tundra 40A ESC). I don't know if it's the extra watts or extra amps that fries the stock motor, but the stock motor ain't cheap, so if you're going to play around with more volts or more demanding props, use the Leopard 960kv.

E-flite Valiant basement madness: Four cell test! (0 min 29 sec)

As a general thumb rule, when flying a newly-modified Valiant, fly with the assumption that you'll lose control and crash, meaning keep it low, preferably over water, below the treeline if near a road, if possible insured and otherwise in a best-effort attempt to abide by the spirit of the AMA guidelines, nowhere near people's skulls. Though if this direction appeals to you, tinkering, I would suggest a Tundra as it has a lot more room inside for giant packs and a dozen sensors while also having a wide envelope, and because it's just not nearly as sexy a plane deserving feminine pronouns, you don't feel as sad when you smash it.
May 22, 2019, 11:23 AM
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Clive66's Avatar
Well, that was certainly a mouthful
May 22, 2019, 02:16 PM
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Andrew73's Avatar
Motor upgrades are too complicated and E-Flite 4S planes (Pitts 850, TimberX etc) are way too expensive compared with stuff like the EFXtra.
May 27, 2019, 12:10 PM
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Anyone know if any other companies props will fit the valiant. I need a new one and there are none on horizons site.
May 27, 2019, 01:06 PM
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Clive66's Avatar
This works great & provides a little more vertical pull, but you lose some ground clearance, which isn't a problem is you're flying from a paved runway.
https://www.towerhobbies.com/cgi-bin...xoC0oYQAvD_BwE

This works to
https://www.towerhobbies.com/cgi-bin...+thin+electric

Haven't tried this one, but it should be OK also
https://www.towerhobbies.com/cgi-bin...+thin+electric
May 27, 2019, 02:21 PM
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David Forbes's Avatar
Been using the ACP 11x7e, works great with the stock motor and ESC
Jun 11, 2019, 06:03 PM
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10x6 prop for 3 or 4 cell Valiant power


My Valiant with a smaller prop (10x6 Master Airscrew) is being used mostly as a trainer. The power output is lower on a 3S 3200 but today a 27 min flight ended with 22 % remaining in the pack. This was mixed type flying consisting of rectangular landing pattern flying using full throttle to 100-200 ft then half throttle until final approach then full throttle go arounds with full power. A few loops and 20 second climbs for deadstick gliding and thermal searching ended our session. I was going to switch to a 4S pack for more lively performance but we stopped because of approaching rain and thunder storm activity in the Tampa Bay Area.

Here are some specs from my Wattmeter for comparison:


Master Airscrew 10x6 prop

Battery Pack/ Amps/ Watts
3S 3200 40C/ 17.6/ 202
4S 1500 100 C/ 27/ 406

Stock 10.75x8 prop

3S 2200 40 C/ 19/ 226
4S 1500 100 C puts amps OVER the 30 amp ESC limit so to protect the ESC and motor a smaller prop is used.

Note: Duration with the 1500 4S is less than 3S but depending on the aerobatics the performance can be outstanding!
Jun 11, 2019, 06:22 PM
Registered User
How do you fit a 3200 battery in the compartment?
Jun 12, 2019, 11:09 AM
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Master Airscrew props are heavy. Stock motor may not handle 4s
Jun 12, 2019, 11:18 AM
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Clive66's Avatar
Just weighed a 10 inch Master prop & a 10 inch APC prop (both are electric series)
Both weigh the same (.7 ounce)

Stock Valiant prop weighs .8 ounce

BTW, I metered the stock prop on mine some time ago & my readings were higher than VicT's.
Full throttle on a fresh 30C 3S 2200 batt. showed 23 amps @ 265 watts.
Last edited by Clive66; Jun 12, 2019 at 11:41 AM.
Jun 12, 2019, 01:12 PM
Registered User
Quote:
Originally Posted by Clive66
Just weighed a 10 inch Master prop & a 10 inch APC prop (both are electric series)
Both weigh the same (.7 ounce)

Stock Valiant prop weighs .8 ounce

BTW, I metered the stock prop on mine some time ago & my readings were higher than VicT's.
Full throttle on a fresh 30C 3S 2200 batt. showed 23 amps @ 265 watts.
Thanks Clive for your info. I wonder what static thrust comparison would be for the 10/6 APC versus the Master Airscrew 10/6.
Jun 12, 2019, 01:25 PM
Registered User

More Mod Ideas


I’ve wanted to put a folder on my Valiant and have a spare Turbo Timber cowl that could take the place of the wide stock Valiant cowl. The folding prop works out real well on the Turbo Timber for vertical dive speeds and for low drag thermal flying. If looks are what you’re after then a 3 bladed Turbo Valiant would be interesting!
Jun 12, 2019, 03:49 PM
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Clive66's Avatar
Still flying my Valiant totally stock.
It's one of only a few planes I've had without needing or wanting any mods at all.
Couldn't even begin to guess how many flights I have on it.
Jun 12, 2019, 05:31 PM
Registered User
My Valiant still remains my most flown aircraft after two years in service, (airframe #1 died during some low altitude inverted shenanigans, #2 now flies on floats, and #3 goes to the field at least once a week.)


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