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Old Dec 12, 2012, 09:27 PM
Should've, Would've, Could've
v8truckin's Avatar
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Pete,

Ya that's why you use em as a starting point and then give a tad bit more up tv. Once you have her trimmed to how you like in the air land and then mark where the are; re-center trim on radio and adjust tv manually to that position marked after flight so your radio trim is still centered.
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Old Dec 12, 2012, 09:30 PM
Should've, Would've, Could've
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Av8er,

Great thats exactly what I would do. You can adjust it as much you like on the ground bit until your in the air you can't tell for sure.
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Old Dec 12, 2012, 10:04 PM
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Originally Posted by Maxthrottle View Post
Which batteries will you be going with? and how much amps do you figure on the 28-58-1s burning to get what will likely be 2.7kg thrust once in the tube. Because I've been trying to see what the transition point from 4S to 5S etc would be for the CS70/12, while keeping the battery weight within <675g or for you <850g for the SU-35.
Dave right in keeping to 4S with the 28-58-1s because the fan load is higher and the KV for those motors are too high (KV: 3180) for higher volts. If you went with other motors, 6S wouldn't be an issue. I've used the 28-58-1 at 6S. Its designed around the wemo mini. But the wemo has a different pitch and wash with less blades.
Damn I replied but it didn't get posted- all lost! Anyway I was looking at the Gens Ace 4000s and 4800s, weight is an issue and the 4800 are 543g, the 4000s 473g, I cant seem to find anything at 60c and higher above 4000 that weighs less than 520g. The Nano Tech 4.4s are 527g but better to go with the Gens 4800s at 543g-- any suggestions!?
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Old Dec 12, 2012, 10:42 PM
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Originally Posted by IntheTubeDeep View Post
Damn I replied but it didn't get posted- all lost! Anyway I was looking at the Gens Ace 4000s and 4800s, weight is an issue and the 4800 are 543g, the 4000s 473g, I cant seem to find anything at 60c and higher above 4000 that weighs less than 520g. The Nano Tech 4.4s are 527g but better to go with the Gens 4800s at 543g-- any suggestions!?
OK hang on I assumed you intended to double the 4000 batts 2x4S in parallel so that you could get at least 4-5 min flight. A 4800 40C may not be near 1:1 but it will be above the 170amp demand. it won't have much in the last 1/4-1/3 of the flight without burning up the batteries. The setup would be lighter by about 100g (100g lighter battery, 60g lighter motors, Xg heavier ESCs, little flight time) than the factory batt weight of about 650g. I'd get 2X4S 3000 in parallel or a 6000 or you'll be limited to a few quick laps and then have to land. You will likely come out at 2.9kg+ and thrust just below that in the 2.7-2.8kg thrust range. Hard to say since the CS70/12 owners haven't posted a lot of clear numbers regarding dynamic thrust. basic fly bys type of flying.
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Old Dec 12, 2012, 11:18 PM
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The TV's must be aligned on the ground.
Trim as a PAIR can be done in flight, but all other factors must be done perfectly before flight.

I had used those TV marks initially, but even after that I then aligned them to each other by a 'plate' made to go across the exhaust sides of both (stiff thick cardboard with a tail piece hole in it). Which already showed the innaccuracy of the marks.
Then at some later time, after redoing stuff, I ended up with then equal but DOWN a bit.... oops. And when I was re-aligning them after that time I found out how really poor those marks are... useless really.
Both sides made to be 'identical' by the marks, and were not equal in reality. So then I used the gap from nozzle face to fuselage face, as that is far more accurate - you are removing the "ball error", and its "slop", and "smaller radius", total error margins. Using two 'fixed faces' that have no error input from themselves. (I had thrown away the cardboard and didn't even remember having done that before! I will have to make one to keep!)
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Old Dec 12, 2012, 11:24 PM
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Thrustline

AV8r, just stick with the centering line markers on the TV units. They have been known to be glued in a little off so you can adjust the thrust line as you go along.
If you find you are adding pitch trim for slower flight and want less for faster, thats CG. If you go to full throttle from level and it pitches up or down thats your thrust line.

Just understand that thrust line is set to counter the wings increasing lift with increase in velocity/thrust. Thus that picture I posted a while back of the wings Aspect Ratio/ AoA to the nozzles and stab. The factory sets it down just slightly.

Don't set the thrust line to compensate for the static low nose angle or something else, as such will mess up your flight trim.

You can always tell if your thrust line is off with a vertical no input climb (this is after confirming your flight surfaces are trimmed). If it pulls to the canopy or belly, CG is out of the picture and if surfaces are neutral the only other thing that can cause the pull is the thrust angle. You don't need to continue vertical for long but you do need dynamic airflow over the wings. Unless you are looking for hover thrust line balanced where the wings lift isn't in play.

DR/Expo, I don't use rates. I set max end points. Then I expo if needed. Go with what the manual says, 35% if I recall but I have mine either at 15% or at 95%. Even with 7 adjustable curve points the transition from little movement to normal shouldn't happen where you intend to fly; i.e. on landing, you have little movement, so it should be above 30-35%. 3D you have a lot of movement, you don't want it between 20%-70% range. But try it and find what you are comfortable with.
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Old Dec 12, 2012, 11:27 PM
Should've, Would've, Could've
v8truckin's Avatar
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TUBE,

These are great batteries and are the lowest C rating u would go, since your doing parallel batteries.

http://www.valuehobby.com/power-syst...4-8v-lipo.html
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Old Dec 12, 2012, 11:32 PM
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Originally Posted by PeterVRC View Post
The TV's must be aligned on the ground.....
Good point Pete. Mine were aligned but you can sit the nozzles on a flat table, power on and confirm the servo positions are not off.
When I did all this it came out 1mm down pitch (or the top lines were showing a 1mm space to the edge) and when flying no matter what throttle setting I had it didn't change level. When I slowed down to a crawl it needed a little stab pitch input.
It flies cleaner this way but you would likely want to go with V8s 1mm up hiding the top center line by 1mm.
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Old Dec 12, 2012, 11:46 PM
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Originally Posted by v8truckin View Post
..., since your doing parallel batteries.
Not sure that he is going with two 4S batteries in parallel. I just took for granted that he was since a single 4S 4000 would give such a short flight time. Two of those would be 724g + parallel connector, he's back to struggling with being over weight with low thrust. He'd at least get 4.5min of flight though.

Those ESCs are 75g each. Anyone remember what the factory ESCs weighed.
Internal SBEC... I would have gone with the 100HV ESC OPTO and an external CCBEC instead of the 110 w/ SBEC.
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Old Dec 12, 2012, 11:52 PM
I did it...
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Quote:
Originally Posted by Maxthrottle View Post
AV8r, just stick with the centering line markers on the TV units. They have been known to be glued in a little off so you can adjust the thrust line as you go along.
If you find you are adding pitch trim for slower flight and want less for faster, thats CG. If you go to full throttle from level and it pitches up or down thats your thrust line.

Just understand that thrust line is set to counter the wings increasing lift with increase in velocity/thrust. Thus that picture I posted a while back of the wings Aspect Ratio/ AoA to the nozzles and stab. The factory sets it down just slightly.

Don't set the thrust line to compensate for the static low nose angle or something else, as such will mess up your flight trim.

You can always tell if your thrust line is off with a vertical no input climb (this is after confirming your flight surfaces are trimmed). If it pulls to the canopy or belly, CG is out of the picture and if surfaces are neutral the only other thing that can cause the pull is the thrust angle. You don't need to continue vertical for long but you do need dynamic airflow over the wings. Unless you are looking for hover thrust line balanced where the wings lift isn't in play.

DR/Expo, I don't use rates. I set max end points. Then I expo if needed. Go with what the manual says, 35% if I recall but I have mine either at 15% or at 95%. Even with 7 adjustable curve points the transition from little movement to normal shouldn't happen where you intend to fly; i.e. on landing, you have little movement, so it should be above 30-35%. 3D you have a lot of movement, you don't want it between 20%-70% range. But try it and find what you are comfortable with.
That ONE picture tells me more information than the whole manual does. Good job man. Thanks. I'm a copy cat .
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Old Dec 13, 2012, 12:00 AM
Should've, Would've, Could've
v8truckin's Avatar
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Ya guess im a lil confused also, just no liking the 4s setup altogether just too many conflicting issues for a good setup for my liking.

142g stock esc no motor wires just esc to stock connector.
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Old Dec 13, 2012, 12:05 AM
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Originally Posted by v8truckin View Post
Ya guess im a lil confused also, just no liking the 4s setup altogether just too many conflicting issues for a good setup for my liking.

142g stock esc no motor wires just esc to stock connector.
For the pair or each? I'll assume the pair. So they were 71g each to his 75g ESCs. So his setup is lighter but what varies is the battery to flight time since he's never getting substantial thrust/efflux from the setup. Ya its just not an ideal setup for this level of thrust/efflux.
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Old Dec 13, 2012, 12:06 AM
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For the pair

I think maybe if it was a belly Lander it would be beter suited to 4s as the weight to thrust would be a lil better. Wasn't the freewings original 4s version a retract-less jet?
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Old Dec 13, 2012, 11:51 AM
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The Standard version 4S didn't have active Thrust Vectoring or rudders. Different motor as well.
Taking the gear off would be like getting a 4S standard version and taking the gear off to get it to perform like the 3D full house. The 4S setup is virtually non existent showing how well that setup was preferred. His setup choice brings it in the ball park of the factory setup in bottom line performance, which we all know doesn't get the 3kg thrust even with the 6S just as the CS10/12 won't, but only for a much short flight times.

That's why I said switch up now before you commit more money to 4S batteries since all he needs is another set of motors. If the CS70/10 is as similar to the CS70/12 as some say, the 28-58-1 was the wrong motor then for this size and likely to be a less than spirited setup now as it was then.
What I'm interested in is how the CS70/12 works dynamically. I expect more thrust but lower speed unless you go with more motor in which case you may as well go with the CS70/10. So 4S CS70/12 sounds like he'll get neither 3D performance or speed for any length of time. Hope my guesses are wrong.
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Old Dec 13, 2012, 03:30 PM
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Originally Posted by Maxthrottle View Post
OK hang on I assumed you intended to double the 4000 batts 2x4S in parallel so that you could get at least 4-5 min flight. A 4800 40C may not be near 1:1 but it will be above the 170amp demand. it won't have much in the last 1/4-1/3 of the flight without burning up the batteries. The setup would be lighter by about 100g (100g lighter battery, 60g lighter motors, Xg heavier ESCs, little flight time) than the factory batt weight of about 650g. I'd get 2X4S 3000 in parallel or a 6000 or you'll be limited to a few quick laps and then have to land. You will likely come out at 2.9kg+ and thrust just below that in the 2.7-2.8kg thrust range. Hard to say since the CS70/12 owners haven't posted a lot of clear numbers regarding dynamic thrust. basic fly bys type of flying.
Yes you're correct I planned on 2 x 4s in parallel, on my Su35 running 6s I have 2 x 3s in series, 3s 4500s and a set of 3s 5000s, they weigh approx 400g each x 2 = 800g, and the CG was good with these up against the cockpit wall(AS far forward as possible) stil have plenty of adjustment room for heavier batts. Now I'm leaning towards 3700 or 3850s
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