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Pumpkin drop event

FT What Did You Do RC Today : Caution Offtopic At All Times

rockyboy

Skill Collector
Mentor
First you want two identical esc's period otherwise you may not even make it of the ground, matched counter rotating props also, both motors have to pull equally. The smaller the esc the smaller and less pitch your prop will have to be. If you have a watt meter you can test different sizes of props to make sure you are not drawing to much. I have a 2836 PropDrive V2 1400kv motor and with a 40A esc on 3S I am spinning a 10X5 prop. Huge thrust and good speed but it could be overkill for your plane, this is one of mine with that combination, https://forum.flitetest.com/index.php?threads/what-did-you-fly-today.57878/post-466671
I agree you want matching motors and props - or at least matching KV motors and props, but you can run with different ESC's as long as they are each big enough to handle the draw of the motor/prop they are connected to. There have been several quad builds where people even used miss-matched motors but in those cases the flight controller picks up the slack. I've run twin engine airplanes with and without counter rotating props, and it was about one or two clicks of rudder trim difference between them.
 

Wildthing

Well-known member
I agree you want matching motors and props - or at least matching KV motors and props, but you can run with different ESC's as long as they are each big enough to handle the draw of the motor/prop they are connected to. There have been several quad builds where people even used miss-matched motors but in those cases the flight controller picks up the slack. I've run twin engine airplanes with and without counter rotating props, and it was about one or two clicks of rudder trim difference between them.
I think if you have mismatched anything you are increasing your odds for a crash. If you have to trim the rudder to compensate for different thrust left to right all your flight characteristics will not be true and centered. Yes if you have a flight controller to take up the slack sure it can work
 

Vimana89

Well-known member
Super windy the last few days. Tried to relaunch my plane after that short, successful flight but the wind was too strong and the slop too real..plus a bit of structural damage I overlooked. Got everything fixed and reinforced as good as I can for next time, but the wind has been preventing that. Maybe I should build another plane or two while the weather is bad.
 

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Vimana89

Well-known member
Wind died down enough to relaunch. Plane was bunk. The tiniest discrepancy on elevon builds can make a completely uncontrollable plane. I have just not figured out how to get elevons dead even. You try to gauge the distance the servos and rods need to be for a perfect angle, then there's all these other considerations like lining the servo up and accounting for wether your measuring with the servo sitting on top or already nested in the cut. I'm not a mathematically oriented person, and this process is frustrating and unintuitive. I think my next slender delta will be AET with a tailplane. That way I can attempt to get the ailerons as even as possible but if I fall short my plane can still fly.
 

SlingShot

Maneuvering With Purpose
At 00:06 you can hear it, and see the dramatic recovery. I'm not exactly sure what happened, but I think I entered an accelerated maneuver stall and induced a snap roll. If you see something different, shout out.


Edit: I now believe that one side cut out -- probably due to overheating. Have now included vents in the nacelles/power pods.
 
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buzzbomb

I know nothing!
Maidened the B-25 SS. I really like this airplane. @buzzbomb at 5:08 I rolled it inverted and made a half lap. Hadn't done much inverted in awhile.

THAT sir, may possibly be one of the best flight videos I have ever seen. That B25 flew absolutely scale and you looped and rolled and did low flybys and went inverted! That was one seriously glorious video.

The Challenges I throw out are not meant for that bird. She is beautiful. The Challenges I throw out are meant for everyone to build something simple and then go out and see what it can do. As I like to say "Get Stupid With It!" I think we are missing a whole lot of potential in what a foamboard aircraft is actually capable of, and we are exploring that in my Challenges.

Your video. THAT's how you do it right. You did it all. Thank you.
 

Hai-Lee

Old and Bold RC PILOT
What I did today was to do a Buddy Box lesson for a complete Newbie, the session lasted through 3 batteries on a Havoc, (Bixler clone).

That was not the exciting part though, (Situation normal actually(, but what happened just a metre or two from where I was standing was!

One of the planes in the air at the time, (a retail twin engined foamie), was flying low along the runway, (in front of where the pilots stand whilst flying), when a motor came loose and fell from the aircraft. The sudden asymmetrical thrust caused the plane roll towards the flight line, (at high speed) and then roll and dive into the ground in the midst of a group of 3 pilots, (not me). The crash was so close though I felt the crash and was showered with a number of the smaller pieces of foam.

The pilot was a very experienced pilot and the plane appeared to be very well cared for and maintained!

Never seen such a crash before and it reminds me that @#it happens!

Have fun!
 

SlingShot

Maneuvering With Purpose
One of the planes in the air at the time, (a retail twin engined foamie), was flying low along the runway, (in front of where the pilots stand whilst flying), when a motor came loose and fell from the aircraft. The sudden asymmetrical thrust caused the plane roll towards the flight line, (at high speed) and then roll and dive into the ground in the midst of a group of 3 pilots, (not me). The crash was so close though I felt the crash and was showered with a number of the smaller pieces of foam.
Wild stuff! That may have been what happened to me. An intermittent blackout on one side.
 

Hai-Lee

Old and Bold RC PILOT
That was an opportune accidente @Hai-Lee .
Not really opportune but actually very scary and it brought home the need for insurance to some of our would be newbies!

Closest I have ever come to "Catching one". My poor student wanted to stop flying immediately out of fear but I refused and the student continued on for another 2 batteries. Student now realizes the true value of FT designs and that EVERYONE crashes sometime!

Have fun!
 

SlingShot

Maneuvering With Purpose
That was an opportune accidente @Hai-Lee . I did some bench testing, and found that I had a configuration problem with my differential thrust.

I had changed the end points on my aux channel. The resulting effect was that I could introduce inadvertent "crazy mode" a la Dave Windestal. One side cut out completely. It's fixed now.

Wild stuff! That may have been what happened to me. An intermittent blackout on one side.
 

SlingShot

Maneuvering With Purpose
Not really opportune but actually very scary and it brought home the need for insurance to some of our would be newbies!

Closest I have ever come to "Catching one". My poor student wanted to stop flying immediately out of fear but I refused and the student continued on for another 2 batteries. Student now realizes the true value of FT designs and that EVERYONE crashes sometime!

Have fun!
Oppurtune for my learning. See above.
 

Hai-Lee

Old and Bold RC PILOT
That was an opportune accidente @Hai-Lee . I did some bench testing, and found that I had a configuration problem with my differential thrust.

I had changed the end points on my aux channel. The resulting effect was that I could introduce inadvertent "crazy mode" a la Dave Windestal. One side cut out completely. It's fixed now.
It is good that something positive came from the crash and I will pass on your "Thanks" as well as my "fears of death" raining from the sky to the luckless pilot next time I see him at the field.

It also shows those who read this thread how sharing even the worst of accurences can help others!

Have a long time enjoying the plane now rectified!

Have fun!
 

Vimana89

Well-known member
Working on a tailed AET variant of my main bird. For ease of manufacture and storage it's scaled down into proper mighty mini range. How this will perform vs my more mid sized models, I'm not sure, but with a 1900kv graupner I can run a lot of mini to mid range stuff. If it's bunk, I'll scale up next time but if not, score. I'm liking the way the profile looks though. Not much historically to go on, as tailed slender delta configurations are mostly seen on concepts for next gen supersonic passenger planes. I'm going with a somewhat hefty elevator and more understated ailerons to smooth out this plane's huge bias.
 

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I am trying to build a huge electric motor. I built a strong electromagnet by wrapping magnet wire around a soft cobalt iron core i bought that is 6 inches long. I figure this would make a very strong motor sense the size is so big. Any ideas as to how to do this? I plan to use it to build a small four wheeler/dune buggy as i think it would be strong enough at that size. I am very light and am hoping to be able to use it for recreational fun. Also is it possible to have the battery for the once build motor be able to be charged by wall outlet or solar pannels. What type of battery do you think this would work for. I plan to have the motor hooked up to a huge ESC and i will have a pedal control the ESC. Is this possible? Thanks