FT Cruiser - BUILD
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Hi Corbarrad,
no problem, all need a starting point for investigation ;-)
Also, I'm not sure to understand well what is "Basic setup on both esc".
Both are connected to battery, once got the positive lead disabled.
ESC are the F-20A from HK, and I did not set anything particular on them.
Did I miss something?
no problem, all need a starting point for investigation ;-)
Also, I'm not sure to understand well what is "Basic setup on both esc".
Both are connected to battery, once got the positive lead disabled.
ESC are the F-20A from HK, and I did not set anything particular on them.
Did I miss something?
Most, if not all escs have a specific procedure that maps their 100% an 0% throttle values to those of your receiver.
With a single motor you won't really notice if it starts up at 3% throttle input and reaches full throttle st 97% stick travel, but if you have 2 engines and 1esc is off a little more than the ozher you'll start to notice it.
Also, most escs have a "brake" setting that stops the prop quickly whrn you cut the throttle. That option might be set on one esc and not on the other.
To make things worse, escs these days aren't hardwired in their behaviour, but may have different firmwares, influencing their throttle curves, soft start/stop times and lots more.
That's why you should get two escs of the same manufacturer, type and if possible production lot for your twin. properly setting them up via the procedure stated in their manual or wit the use of a programming card, if available will save you some hesdsches down the road... or runway, as it were.
With a single motor you won't really notice if it starts up at 3% throttle input and reaches full throttle st 97% stick travel, but if you have 2 engines and 1esc is off a little more than the ozher you'll start to notice it.
Also, most escs have a "brake" setting that stops the prop quickly whrn you cut the throttle. That option might be set on one esc and not on the other.
To make things worse, escs these days aren't hardwired in their behaviour, but may have different firmwares, influencing their throttle curves, soft start/stop times and lots more.
That's why you should get two escs of the same manufacturer, type and if possible production lot for your twin. properly setting them up via the procedure stated in their manual or wit the use of a programming card, if available will save you some hesdsches down the road... or runway, as it were.
OOOOOHH ! OK,
I was not aware about this "Brake" setting particularity in case of twins... And also, really interesting your answer, thanks for your time
So OK, My 2 ESC are the same model, same manufacturer, I will buy a programing card to disable brake on the second ESC. I should answer you in a couple of Days/week, depending of the delivry time ;-)
Thanks again for this explaination.
I was not aware about this "Brake" setting particularity in case of twins... And also, really interesting your answer, thanks for your time
So OK, My 2 ESC are the same model, same manufacturer, I will buy a programing card to disable brake on the second ESC. I should answer you in a couple of Days/week, depending of the delivry time ;-)
Thanks again for this explaination.
OOOOOHH ! OK,
I was not aware about this "Brake" setting particularity in case of twins... And also, really interesting your answer, thanks for your time
So OK, My 2 ESC are the same model, same manufacturer, I will buy a programing card to disable brake on the second ESC. I should answer you in a couple of Days/week, depending of the delivry time ;-)
Thanks again for this explaination.
Glad to help.
Take a look at the "files" tab on the article details on the HK site. It contains the manual for the ESC as well as some useful files describing how to perform settings without a programming card. Just a word of warning, these proedures usually start off by powering the ESC on with the TX at full throttle. Take the props of your motors before you start. The engine shouldn't come to life hile you perform these settings, but you never know and it's better to be safe than bloodied.
i want to build a cruiser but i would like to get everything from hk (I'm almost platinum) that's besides the point. i would like to use 3 blade props for the look and i would like motors with some oomph and im going to do differential thrust. i would like to use 3s 20c or 45c lipos. i have the 45c's already. i was looking at the motor they recommend but it had the wires near the shaft not behind it. is that something you can change?
i know i asked alot of questions but thanks in advance
i know i asked alot of questions but thanks in advance
I'm currently on break at work, so I can't go into specifics or link anything, but everything you plan should be possible.
The c-rating of a battery only denotes how much amperage can safely be drawn from it. fo rexample a 2200 20c should not be put under a load greater than 44 Amps while a 2200 45c should be able to take up to 99 amps without puffing (for a little more than a minute before yout capacity is exhausted and you end up ruining it anyway)
There's no pennalty for drawing less than the max, though, so using a higher rated battery of the same capacity shouldn't pose a problem. the criser is built to take quite a bit of weight after all.
Most motors with a front plate mount can be converted to back plate mount by either pushing the shaft through or turning the shaft around. The method to achieve this varies from motor to motor. You might want to do a search for a video about the procedure before commiting..
As for the three-bladed props I think the rule of thumb used to be that a three blsded prop will generate about as much thrust as a two-bladed one that is 2" larger in diameter and 1" higher on pitch. so a 3- bladed 6x3 should equal a two-bladed 8x4. You should be sble to find calculators for that online as well, where you can put in your power plant specs, motor and prop and get values for the expected amp drsw and thrust.
Hi Guys
first time on the Flite Test forums.
I just completed my FT Cruiser build. We don't get the dollar tree foam in New Zealand, but the foam available is I think slightly heavier and slightly thicker. I was pretty happy with the build and finished it in the (Planes Movies) Bulldog colours. Unfortunately on take off right away I could tell that it was way to tail heavy.
Can someone please confirm the balance point from the leading edge. I went from the marks for the as per the build vid which put the C of G 72mm behind the leading edge. I didn't look right to me, but I'm not a designer, and sure didn't fly right.
I'm definitely going to build another so I want to get it right.
Any help will be appreciated.
first time on the Flite Test forums.
I just completed my FT Cruiser build. We don't get the dollar tree foam in New Zealand, but the foam available is I think slightly heavier and slightly thicker. I was pretty happy with the build and finished it in the (Planes Movies) Bulldog colours. Unfortunately on take off right away I could tell that it was way to tail heavy.
Can someone please confirm the balance point from the leading edge. I went from the marks for the as per the build vid which put the C of G 72mm behind the leading edge. I didn't look right to me, but I'm not a designer, and sure didn't fly right.
I'm definitely going to build another so I want to get it right.
Any help will be appreciated.
nagromnewo
New member
I finally maidened Bulldog (from the Planes movie), a modified FT Cruiser today, and all went well except I've got to find some smaller props and maybe some smaller motors. I was never over 1/4 throttle and the plane was still crazy fast. When 1/4 throttle is too much, the throttle becomes an on/off switch...
The CG is just on the aileron servo horns with the servo horns towards the trailing edge (HXT900's), so maybe 1/4" further forwards than FT suggest. The plane felt just a little tail heavy, so I will move it a bit more forwards.
He's got (Bulldog is definitely a he) 2 x Suppo 2212/10 motors swinging counter rotating 8x4.7 props and 2 x 1600mAh 3S batteries in parallel. All the paper has been removed from both sides of the Adams board and replaced with tape so the bare airframe is probably lighter than stock. I'm thinking maybe 7x4 props or even smaller. I have the same motor and a Master 8x4 on my FT Spitfire and that's plenty. Anyway, apart from being too darn fast and difficult to slow down with way too much power, the plane flew great.
Owen
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ClearSkiesCalmWinds
Active member
Very cool! Love the set up. Hopefully you can post a vid on this bullet. Cheers!
nagromnewo
New member
Hi
I found that he balances just a tiny bit further forwards with a single 2200mAh 3S in the nose instead of the two 1600mAh batteries, so that is probably what I'll go for. He was a little tail heavy on the maiden, so moving the CG a little forwards will be good. The CG given on the plans is too far back.
Going 2S might work, but I'm not sure where I'd find a 2S that fits the same space as a 3S 2200 and weighs the same. 3S is more efficient than 2S anyway, so I think the solution is going to be smaller props which will save Amps too. I've ordered two sets of 7x4 Master props (regular and counter rotating) so we will see when they arrive. I won't fly this one again until the new props arrive.
I need to get a new battery for my Mobius so I can get some video and stills both onboard and from a hatcam.
Owen
I found that he balances just a tiny bit further forwards with a single 2200mAh 3S in the nose instead of the two 1600mAh batteries, so that is probably what I'll go for. He was a little tail heavy on the maiden, so moving the CG a little forwards will be good. The CG given on the plans is too far back.
Going 2S might work, but I'm not sure where I'd find a 2S that fits the same space as a 3S 2200 and weighs the same. 3S is more efficient than 2S anyway, so I think the solution is going to be smaller props which will save Amps too. I've ordered two sets of 7x4 Master props (regular and counter rotating) so we will see when they arrive. I won't fly this one again until the new props arrive.
I need to get a new battery for my Mobius so I can get some video and stills both onboard and from a hatcam.
Owen
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mesolost
Junior Member
I had a beautifully flying storch and retired her. Then I built another and this time I did the minwax thing but I think that counted as paint and cursed my plane before I maidened it so it got the boot, literally. I want to make this plane specifically for FPV flight but I have limited materials and funds. Is it absolutely crucial to have counter rotating props or is it ok that I just trim the ailerons to counter the torque roll???
gabrielete
New member
A new cruiser is born.
WilberMaker
Junior Member
That is a really nice cruiser. Well done! :applause:
Torque roll is generated by the acceleration and air resistance of the prop. Therefore countering it with airflow would be inexact.
Can trim overcome roll tendencies? Sure, but it would have to be a really smart trim/mix that knew how fast the aircraft was going, and adjusted it based on the throttle input and changes in order to properly smooth out torque roll.
In my opinion, a gyro might be a somewhat better solution for FPV torque roll concerns. It would respond to un-commanded deviation along the roll axis and move the ailerons to compensate.
For FPV, a gyro might make for better video anyway, but it's also more expensive then buying a set of props!
Capt_Beavis
Posted a thousand or more times
It is not crucial to have counter rotating props. My Mini Cruiser did not have them and it had no torque tendency. I think Torque is actually worse on a single motor plane because it is right at the center of the plane, all of the torque is on the same axis, with a twin engine the torque from each motor is on a different axis.
mesolost
Junior Member
That's good to know ^_^ I'd do the different props but you'd still have the screw thread direction issue so I'd rather stick to the cheap motors I can destroy and not have to worry about a whole second set of stuff I need to start keepin, at least not until I start doin quad-copters =p Once I start doing those I'll just retire quad motors to aircraft =p
gabrielete
New member
The first time I hate it. Now after some little adjustments I love it.
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