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Mini Trainer is here. Can I build it? Can I fly it?

Jimun

Well-known member
#61
Thanks guys for you comments and encouragement. Pony1023, your post was long but worth every word. Thank you.

Markus, I thought about that. I had the part, so I just traced. It worked, just not well. I think next time i will try the plan down load.

Casey I like your paint color. Absent the D-Day marker Bands, it could be a modern UAV.

Life has been keeping me away from finishing this two hour project in under a week, or has it been 10 days. I finished the tail construction several days ago, but again life got in the way. So here we go building-fixing the tail.

With the new rudder and elevator cut out and the bevel sanded in it was time for a dry fit.



Hand cut, the slot in the elevator for rudder keel was a bit loose, something I needed to watch when I glued everything up.



That came out fine.

When I did the dry fit of the tail onto the fuselage, I noticed this.



Either the slot in the fuselage is too long-couldn't be, its factory, or I cut my Rudder-Elevator out wrong-yep. That's why i think Markus' idea of downloading the plans might be a touch better than tracing. You might notice in my pictures the Rudder control relief is on the right side. In the Construction video, that relief is on the left. Little details like this can be confusing to a first time builder. But with the help from the folks here i have learn to not sweat the small stuff, just adapt. There is another mistake rearing its ugly head, if you look real close, but we'll get to that. This "short" elevator can't be ignored, as it will bind the rudder.



To adjust for the "short" Elevator, I cut a small piece of foam out to use a spacer and glued it in the front part of the slot in the fuselage.



That correctted the "shortness. But it also shows another mistake if you look close.



And finally the tail is all assembled.

At this point I had not yet spotted my mistake. I'll cover that and it's correction Adjustment next.
Good job. I also got my tail backwards on the first try and had to adjust the controls to the right sides with a little bit of cutting away. I had flown it several times until it was irreparable and built a new fuselage and tail. My TT is all scratch built. I have seen some seasoned builders glue things wrong. So don't get down you will get it up:D. It is just part of the process. Remember the moto:

Build, Fly, Crash, Repeat.
 
#64
I am working up the courage to hook up the electronics. I am a bit intimidated.

I have noticed that the motor housing rotated with the prop, should it?
Yes, the motor housing should spin with the prop.
On Outrunner motors (which is what you have) the outer bell or housing spins, while the stators on the inside stay still.
 
#65
Okay Thanks Grifflyer. I thought I broke it.

Will go look for the basic Video series and see how to correctly connect motor to ESC to receiver.

I also suppose I need to get the batter out and charge it.
 
#66
Oh, I though I was intimidated before I just got the batteries and charger out. I am an instruction reader. I just read the instructions, now i am also scared. Should I have the Fire Department on standby?
 

buzzbomb

I know nothing!
#68
Oh, I though I was intimidated before I just got the batteries and charger out. I am an instruction reader. I just read the instructions, now i am also scared. Should I have the Fire Department on standby?
Lipo batteries require some TLC. Don't charge it unattended. Don't overcharge. Don't discharge below about 30% (loose rule of thumb, lower discharges happen) and store at about 40% charge (also a rule of thumb.)

You'll want to get a fireproof Lipo charging bag (charge the battery in the bag) and a metal container to store your batteries in. Many of us use an ammo can you can pick up at Walmart for about ten bucks. Remove the rubber seal and it will allow venting when the can is closed.

If the battery ever seems "puffy" or becomes physically damaged, it's useful life has ended and needs to be replaced. Lipo batteries are not inherently dangerous, but they can catch fire. Simple precaution is all you need.

You've been working hard to get to this point. It wasn't too long ago that I was posting my first build thread with a Tiny Trainer. Don't stress the electronics. Follow the instructions to bind your receiver and don't forget to calibrate your esc.

The motor plugs into the esc. The esc plugs into channel three on your receiver. ("S" is the yellow wire, "-" is the black or brown.) The rudder plugs into channel four and the elevator is channel two. That's it.

Happy flying!
 
#69
Oh, I though I was intimidated before I just got the batteries and charger out. I am an instruction reader. I just read the instructions, now i am also scared. Should I have the Fire Department on standby?
Double D,

I was also intimidated. Although I am by no means trying to inform anyone there is no danger. I also have come to understand, it's not as bad as I thought when I started purchasing stuff for the batteries. Research on the internet (see the ones I like below) helped and left me with the take away is it's not quite as scary as reading everything makes it sound either. I believe the legal implications, tied to Lipo batteries make all the warnings scary to the "newbies" like me. So nobody can tell me I wasn't warned. And yet when I watch more videos, and research more, I came to the conclusion (for me), it's not quite as bad as it sounded with the info I started with.

It would appear that a high percentage of Lipo fires are caused by one of three issues:
1. Overcharging (which includes cell maintenance).
2. Poorly manufactured or "cheap" Lipo batteries.
3. Batteries that have been damaged by as something as small as being dropped (or in our case a crash).

With that said, I didn't go the Lipo bag route. I bought a "bat-safe", and store my batteries in a .50 cal metal ammo can that has been modified. Flite test has info of an awesome solution for a "battery bunker", and in that video they showed something that I really thought was awesome from a club, using a bag of sand and cinder blocks for charging (I wish I went that route).

I feel you might get some benefit from these:
Electronics:
Episode 6 of the beginner series.

Batteries and Safety:
Episode 7 of the beginner series.

I personally also liked these, but for me, knowing is half the battle.
Flite Test - Connecting Electronics
Flite Test - Lipo Battery Bunker
https://rogershobbycenter.com/lipoguide (I do not support this hobby store, and don't believe it's anywhere near me, this was just the most informative for me, to learn ALOT.)

I found this interesting, and comforting (tied to my opinion above). I would have never thought a Lipo battery could be dropped into plain tap water after my initial warnings. I will also point out how many times Josh B. says not to do this at home (But it still didn't do what I thought it would).
Flite Test - Waterproofing Electronics

I hope this helps you, even though two of these you were already heading towards.

Pony
 

basslord1124

Well-known member
#70
Yeah reading about them does leave you a sense of paranoia. I still have some fear and I've been doing RC a few years now. I can tell you that in the past few years I have not had a battery blow up/catch fire yet. 99% of the time I charge them at 1C and I monitor them very closely while charging. I have a few now that are sort of semi-damaged, so my fear is even higher now, BUT I am watching them.

Just charge them properly (do not overcharge, run down too low, etc) and watch them close while charging. Do what everyone has mentioned so far on the topic. ;) And ya know, really if you think about it...any battery, not just lipos, can cause damage as a result of misuse and/or age.
 
#71
Great job on the build - you're likely about to fly... here's some suggestions:

One of the next few steps will be putting on the prop - make sure you do more than hand tighten it, or you might be trying to find the prop and the prop nut after they fly away by themselves without the plane. Also watch your fingers - even these little props can do a lot of damage to a finger. Always keep clear of the blades, especially when first plugging in the battery (which is a bit hard on the TT)

On your first flight(s), expect to crash... a lot, you'll likely need to replace a propeller or two and possibly re-build the nose section and/or the power pod. Remember the sticks on the controller are not on/off switches - if you provide too much input the plane will start doing weird things, especially if you have the radio set to high rates. Give the sticks small nudges - if you're hitting the ends of the sticks, you are likely over-controlling the plane, and it will take longer for it to level out to even flight.

Fly in a large open area without trees like a soccer or football field. Retrieving planes from the top of a tree canopy is not easy or fun. Also be aware of where the sun is, and try to not fly your plane in-between the sun and yourself.

Sorry - re-reading this seems to be a fortune cookie version of flight advice, but I'm hoping it's helpful.
 
#72
Great job on the build - you're likely about to fly... here's some suggestions:

One of the next few steps will be putting on the prop - make sure you do more than hand tighten it, or you might be trying to find the prop and the prop nut after they fly away by themselves without the plane. Also watch your fingers - even these little props can do a lot of damage to a finger. Always keep clear of the blades, especially when first plugging in the battery (which is a bit hard on the TT)

On your first flight(s), expect to crash... a lot, you'll likely need to replace a propeller or two and possibly re-build the nose section and/or the power pod. Remember the sticks on the controller are not on/off switches - if you provide too much input the plane will start doing weird things, especially if you have the radio set to high rates. Give the sticks small nudges - if you're hitting the ends of the sticks, you are likely over-controlling the plane, and it will take longer for it to level out to even flight.

Fly in a large open area without trees like a soccer or football field. Retrieving planes from the top of a tree canopy is not easy or fun. Also be aware of where the sun is, and try to not fly your plane in-between the sun and yourself.

Sorry - re-reading this seems to be a fortune cookie version of flight advice, but I'm hoping it's helpful.
This is so true! Don't be like me, do what everyone up thread said about keeping your Li-Pos in an ammo can. I live extremely close to a fire department house, so a fire would be quicker to respond to. I really need to get an ammo can. Adding to joelspangler's advice, when you do maiden your plane, fly with the sun to your back and fly in a circular pattern. Choose which direction you feel most comfortable with (Left or Right) and keep it flying in circles. That's how some pilots overcome directional confusion. You see, when a plane is flying toward you, left and right on the controller become reversed. (Obviously) Me, I'm able to remember and turn whichever way knowing it's opposite, but for beginners, like my dad it gets pretty confusing. Anyway good luck!
 
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#73
So we watched the video on electronics connection. Pretty simple pretty straight forward. Yep? Nope!

We have 2 Spectrum DXe Transmitters and 2 Spectrum model ar620 receivers.

Step 1, connect bind plug.

We look through all the boxes and a packages, on the floor, under the table, every where, no bind plug. We look at the enclosed instruction and they say and show Step 1 connect bind plug. But, we have no bind plug. After much dis-cuss-in. We call Flite Test, they say oh, you don't need the bind plug anymore, just hold down the bind button. Okay thanks. Geez, why don't the instructions that Spektrun sends with the transmitter say that. Grrrrr.

So we move on to connect wiring, new problem. The wiring harness we have are color code yellow-orange- brown. The orange wire is in the middle so it is obviously hot. These colors don't match the colors in electronics video, so looking at the wires coming out of the ESC, we have no way to tell which wire is the signal and which is the negative. Having concern and not knowing for sure that reversing polarity might damage any thing, we make another Phone call to Flite Test. We find out the yellow wire is the signal wire. How were we to know that with out instructions or guidelines?

We follow instructions some more and we finally get motor to run and servos to move flaps and rudder. We need now to center the servo's.

Frustration level was pretty high yesterday. The Electronic video was good. It told us what we needed to do, we had try and figure out how to do it.

Negative points to Spektrum with including BAD instructions. For a person that is experienced, probably not an Issue. But for new unfamiliar people, going step by step for the very first and being told in the instructions to plug in the bind plug, and that bind plug no longer being required is a big deal. Thumbs down to for Spektrum.

Color code, How did the technician know the yellow was the signal wire. That issue needs better addressed in the video or written instructions with the ESC. What colors are used for what functions. This may be covered somewhere already, but where?

All this is sorted out for now, we move on to centering servo's.
 

FDS

Well-known member
#74
Yeah, the lack of standard servo lead colours is infuriating. I end up looking them up all the time on the web.
 

basslord1124

Well-known member
#75
No harm is done (at least none that I have encountered) if you plug a servo wire in backwards. It just won't work basically or your ESC won't beep. If wrong, just flip it around.

Yeah up until recently, Spektrum changed over to the push button bind setup on the receiver and now you no longer need a bind plug. I haven't even checked one out yet as I've been using the Spektrum compatible receivers (Lemon, etc) and they still use bind plugs.

I know being new this is frustrating with these manuals and things not matching, but trust me, Spektrum/Horizon Hobby manuals are pretty top notch compared to the Chinese to English translation manuals I have seen. *shudders thinking about it*
 
#77
Well, now we are having fun. Granddaughter is trying get her servo's centered with no luck. Rudder moves, elevator moves, motor revs, "in-structions, De-structions who needs them, lets go flying" she says.

She give me a preflight briefing, She tells me she is going to say "3-2-1 Throw!"

So I get ready to throw, she starts the count down, "3-2" She opens the throttle wide open , as she says "1" there is a horrible racket, and her entire power pod goes flying off down range. i am left there standing, still holding onto a Tiny Trainer with no power pod. After I get through laughing and laughing and laughing, I look and see she never put in the bamboo cross pins to hold the power pod in the fuselage. So I laughed some more.

This crash pulled one of the connectors off one of her motor leads. I loaned her the power pod from my plane. So off we go flying again. "3-2-1-Throw!" I do throw and the plane takes off with lots power and noses straight into the ground

Did I mention, earlier that she couldn't get the servo's to center, did I mention it was the elevator, did I mention it was sticking in full down. More laughing. Bad news the tail is is broken right in front of the rudder-elevator. Laughing now muffled a bit.

She is learning the Foam board Aircraft motto- Build-fly-crash-repair-repeat. as she repairs her plane.
 
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#78
Sorry to hear that that attempt number one wasn't successful and resulted in damage. Might want to try some glide tests over tall grass without any throttle until it glides fairly well. I'm not sure if in the rush if the center of gravity was checked, but that's another critical part of getting the plae to fly correctly.
 
#79
Yes, I agree with joelspangler, CG is EXTREMELY IMPORTANT! Also, if you tried the glider game I suggested earlier, using the glider nose, she might've found the problem earlier, even so I think I can say with near certainty that everybody's first maiden flight doesn't exactly go as planned! But if you're patient then the first flight that works will be even more special, and you'll be thinking "I don't think I would have wanted it to happen any other way, this journey to success was amazing!" Good luck on your maiden Double D! You never know, yours may work really great! Can't wait to read about it
 
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Hondo76251

Well-known member
#80
I can sympathize with the wiring as well... Welcome to the Hobby! :ROFLMAO:

That would all be good and well if they kept the pattern the same (even though the colors vary) but if you get into the micro stuff you'll find that that changes as well (and then you DO burn servos/esc/receivers) but thats another story! lol

With the standard size stuff you're working with you should be fine to plug in and find out which way is which. Nothing gets hurt with a servo's signal being ground or vice/versa (why having the (+) in the center is actually the best idea, and universal for MOST things)

I find that this little guy is awesome for builds...

https://us.banggood.com/Wholesale-W...0.html?akmClientCountry=America&rmmds=myorder

you can use this instead of worrying about binding a receiver and all that jaz while you're building. It even has a position for centering the servo... I usually power it with an old drone 1s battery (again, remember that the center pin is the positive one)

This is a great hobby, in part because its not easy... you know whats easy? Video games!

There is no "reset" here, that's why this is such a valuable experience to the younger generation. We can teach so many life lessons and have fun doing it! I'll leave you with one of my favorite and most underrated quotes of all time from former US President Calvin Coolidge...

"Nothing in this world can take the place of persistence. Talent will not: nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not: the world is full of educated derelicts. Persistence and determination alone are omnipotent."