RC newbie, advice needed

[BodgeIt]

Hi guys, thanks for introducing me to RC flight!

First off, thanks for the youtube videos. They are funny, informative and entertaining. I have never flown an RC plane before (I have flown 2 real planes, so understand the theory). I enjoy building stuff, having made my own glidetracks etc for my camera's, so a good starting point for me would be the 'swappable' series as opposed to a shop bought RTF.

I am hoping to start with a FT flyer and storch, and then once I have battered those into submission maybe try the others out. I knew nothing about motors, esc's, props etc before I started watching your videos, so I am trying to figure out a 'one size fits all' power pod build. So, this is what I have so far although I may be completely wrong. I went a little bigger on the battery as its quite a drive for me to get somewhere I can fly so prioritised flying time. My (limited) understanding is that I can swap props for a bigger, higher pitched prop for faster, or smaller with lower pitch for slower, so will use that to limit power for the smaller builds.

Transmitter + Reciever: Turnigy TGYi6
Prop: 11x3.8.
Motor: originally a D2836 1100kvedited for a DT750 (changed as earlier motor was wrong)
ESC: Turnigy 25amp Plush ESC
Battery: Turnigy 2200MaH 3s 30C
Low Battery Alarm: Hobbyking 2-8s alarm
Servo's: HXT900

As I said, I am completely new to this so may well be completely wrong with what I think would work. I would be very grateful if you could tell me if im on the right lines, or if I am way off with my understanding of how it all works. I know you must get hundreds of threads like this, but my local model shop were no help at all, telling me scratch builds werent worth trying, and then trying to push me into an RTF they had on special

Thank you for your time (and hopefully your help),

BodgeIt.

 

[Corbarrad]

If you're going for a relativley tame Storch you should be doing OK with that setup, The battery would probably be too heavy for an ft flyer

The only thing that caught my eye is that the motor you selected is front mounted, which means it would end up inside the power pod. You'd have to either get creative with the pod or pull the shaft from the motor and turn it around, which may or may not work fine. For a beginner I'd recommend going for a bell type motor with similar specs or a rear mounted motor.

(I'll have a quick look and see if I can post some.)
Edit: here we go: for the Storch I'd go with this one:

Turnigy D2836/8 1100KV Brushless Outrunner Motor
and the 9x6 prop.
If you compare where the wires come out you'll see what I meant by front mounted vs rear mounted motors

For good measure here's the hexTronik DT750 Brushless Outrunner 750kv (USA Warehouse) right out of the recommendations page for the Storch.
This one's a "bell type" motor. sees a lot of use in tricopters and quads as well. I'm not sure if I'd want that long, gangly shaft sticking outof my plane, though.

The turnigy should contain a collet style prop adapter (The 2826 2200 I bought a while ago for my hawksky did), which is a neat and tidy solution for the Storch.

Can't tell you much about the FT flyer, because it never caught my fancy. I'd been flying before I found flite test and three channel rudder/elevator planes never did it for me. This changed recently when I found that a plane doesn't need to be a wallowing scow without ailerons via the HiTech EHawkeye, but that's a whole nother story of joy and grief.

 

[Snarls]

Welcome to the forums BodgeIt! If you have never flown RC before you made a good choice by going with the swappable series instead of RTF. You''ll save money and learn a lot more about the workings of RC aircraft. I would start with the Flyer as your first plane because the build is less involved, meaning if you wreck you can easily repair or rebuild.

Your parts list looks good, everything should work together. Just don't forget the little things like the NTM accessory pack, bullet connectors and XT60 connectors for your ESC

Good luck and fun flying!

Edit: As Corbarrad said, the 2200 battery may be too heavy for the flyer. The NTM motor can be front mounted, but with the accessory pack it mounts in the back like most motors.

 

[BodgeIt]

Wow, thanks for the fast response! I had no idea that motors have different mounting positions, so thanks for the information. I will be aiming to start with a flyer/storch, depends how ambitious Im feeling for a first ever build. Will I be able to use the same set up for something faster if I change the prop for something bigger with a higher pitch, something like a 9x6? Im not sure my understanding of power/speed is correct...

1100Kv = 1100 turns per Volt. Bigger prop, higher pitch = more 'pull' through the air per rotation, at the cost of more power used trying to turn it.

Also, is the battery mAh the scale for flight duration? for example, could I use a higher mAh unit for longer flights, but the same power?

Thank you again, it really is much appreciated.

 

[BridgeInspector]

The motor and battery are too big for FT Flyer. The flyer electronic specs can be found on the build article (from memory :24g blue wonder , 12amp ESC, 2 or 3s 500-800mah).

The motor should work for storch and is a rear mount but you need to add the recommended accessory pack to mount it.

 

[Bayboos]

Flyer and Storch are very different. For sure, both are good (perfect?) trainer planes; but the Storch is much more complex (in terms of design and build process), and - of course - bigger. As others said before me: power setup that is suitable for one of those planes is far from it for the other. I know that the Storch can fly with 24g motor (80W) simply because mine does (see this video: Storch LIGHT); while 250W would be an overkill for FT Flyer, effectively turning it into a heli (without proper means to control it).

Your understanding about Kv and mAh is basically correct. Both are a bit more complex, but what you described is a very good starting point Also, you can find much more info about that in THIS EPISODE of FT's Beginner Series.

Good luck.

 

[BodgeIt]

Thank you for your posts. I figure I will just jump straight to the storch (maybe over-ambitious) but I figure its best to build something you like the look of. I honestly think the electrical bits like binding transmitters, setting up the ESC will cause me more problems than the actual foam board building, as I love 'hands on' stuff and building stuff out of foam board is right up my street. Im currently spending a bit of time on FMS rc flight sim so I hopefully dont nose dive into the floor on my first flight (who am I kidding, we all know thats EXACTLY whats going to happen). Im off to purchase a new glue gun and some other tools on tuesday, so I will get cracking as soon as I can. Im going to go and watch the beginner series all the way through, I think I need to learn as much as possible so I dont have to post silly questions too much

Thank you all again, I really am grateful for the information and advice as it all seems a bit confusing at the moment.

 

[Corbarrad]

Welcome to the forums BodgeIt!
...
The NTM motor can be front mounted, but with the accessory pack it mounts in the back like most motors.

Wow, you do live and learn... I've seen the acessory set before but never thought about using it to convert the motor from front to rear mount.
On previous motors I just punched the shaft through and put it back in the opposite way around... might not work with some shafts, though.

The Storch is a much more involved build admittedly but it also fits my idea of a plane sooo much better.

Now that we got the minis, though you might want to build one of em even if you don't plan on flying it.
It will teach you all the advanced build methods (save the foldover-style wing) without wasting a huge amount of time or materials.

And yeah, in hindsight a welcome to the forums might have been the polite thing to do.

 

[rcspaceflight]

I had two of these motors (I bent the shaft of one of them): HobbyKing 2824 1300kv

The down side is that it's only available in the international warehouse and with it getting close to Thanksgiving, it can take a while with the Christmas rush for your package to show up. But it comes with a prop saver. I use a prop adapter for mine (which might be a good idea to buy one too).

I use that motor with a 25amp ESC and an 8x4 prop. It's a really versatile set up that doesn't weigh too much. Yes, there are lighter set ups, but it's great with a 2200mah 3S battery and a 40" wingspan plane. Also, I think I could use a bigger prop, but with the 8x4 I can fly full throttle for the entire flight without anything getting any where near hot.

^ (mentioned set up was used on my Cessna Skymaster and One Sheet Swappable Trainer)

You could certainly go with a different motor though.

But I think it would be a great idea to start with an FT Flyer, but buy a smaller 3S battery for it. As nice as a 10-15 minute flight time sounds, it is going to take you a while to be able to fly for that long. Having a light plane means it'll crash better. Go with a 500-850mah 3S battery for an FT Flyer. But also get the 2200mah 3S for future builds (with the same motor/ESC/prop set up).

 

[rcspaceflight]

Oh, and don't forget a soldering iron. You're going to need to know how to use one for this hobby. I know of no ESCs that come with connectors already on it. All of them come with bare, ready to solder wires. And don't forget to buy connectors. Most motors that come with connectors on them have 3.5mm bullet connectors. Most batteries that Hobby King sells have XT-60 connectors.

 

[BodgeIt]

I think I will just buy 10/20 XT-60s and bullet connectors as I will definitely forget them in future. Soldering iron will be purchased tuesday, along with a glue gun and other stuff (thanks for the heads up, I would of forgotten that too). I need to have a look around the forum as Im not sure which foam board that is sold in the UK would be best.

Rcspaceflight: You mention how you can fly with a 8x4 without anything getting hot. Please excuse my ignorance, how does prop size affect the heat build up? Im worried now that my idea of changing prop size to suit different speed builds(8x4 for storch, 9x6 for delta for example, and leaving the rest as it is) might not be such a good idea.

 

[rcspaceflight]

The bigger the propeller, the more load on the motor it has. Well, the more work the motor has to do to spin it at the RPM (Volts times KV) that it wants to spin at. More work/load means more amp draw. Motors always have a "max amp draw" and if you go past that, you're going to burn out the motor.

Also, if the amp draw goes past the ESC rating, you can burn out the motor or ESC. Also, if the amp draw goes past the "C" rating of the battery, well, again you can burn out the motor or ESC. The battery can even get hot is the amp draw for any part of the system sees too much amp draw. (I once got a motor hot because the ESC was rated too low.)

Too much amp draw is bad for all of the parts of the system and the prop determines the amp draw (for the most part).

http://flitetest.com/articles/choosing-a-propeller

The "C" rating of the battery tells you the amp draw the battery can handle, but you have to multiply it by the amps of the battery. So a 2200mah battery with a 20 "C" rating will actually be 20 x 2.2 and a 500mah battery with a 20 "C" rating will be 20 x .5

 

[rcspaceflight]

I need to have a look around the forum as Im not sure which foam board that is sold in the UK would be best.

From what I've read, Depron is your best bet. Flite Test uses Adam's Readi-Board because it's super cheap in the United States. Depron is expensive here. In the UK Depron is super cheap (they use it to insulate floors) and "poster board" (as it's called in the UK) is expensive. The main difference is that what Flite Test uses has paper on both sides. But you can cheaply add paper to Depron (or use packing tape).

http://www.youtube.com/watch?v=PbyVGfB1oCg&list=UUlkL_Hmktyh9R_FzwSPjXmA

 

[BodgeIt]

Ahhhh, Maths!! Im now worried about all the stuff I picked out. Its getting pretty late now, but tomorrow I will go through the list in the first post and try and work out if my list is safe to use together. I thought that as long as the motor ''max draw'' was lower than 80% of the ESC rating, and the ESC rating was less than 80% of the batterys 'C' rating, I would be fine. This stuff is hard!

I will have a look around for Depron and see where I can get it locally. Thanks again, you guys are awesome

 

[rcspaceflight]

I linked the wrong Flite Test episode. I meant this one:

 

[electricRC]

I try to pick an ESC rated one or two 'steps' above the max draw of motor. So a 7A max draw rated motor would get a 10-12A continuous speed control, a 10A motor max would get 12-15A continuous speed control, 20A max motor would get 25-30A, and so forth. It is a little easier than finding all the specs and trying to do math.
Another thing to keep in mind is overpowering slightly can be good. If you have a plan that flies the way you like at 50w, if you use a 60 watt or even 70 watt motor the motor itself will have to work less to do the same work. Now you still should match equipment (battery, speed control) to larger motor, but it will be more efficient and create less heat. Think of going to the grocery store, it will be easier and less energy used to pick up a gallon of milk than your kid, but in the end either one of you can do the job.
Heat is also a measure of efficiency in electric components. A warm component is getting higher efficiency than a very hot one, whether it be a motor, speed control, or battery. A good example is light bulbs. Remember the old bulbs? Turn one on for 5 minutes and you couldn't touch it, but you can have an LED bulb on for hours upon hours, and still handle one. This is a good analogy for props. Change prop size and/or pitch, and power/efficiency will change. A 5x4 to a 6x4 [diameter] is a change, a 5x4 to 5x3 [pitch] is a change, and 5x4 to 6x5 [diameter and pitch] is a change. Like those light bulbs, each bulb is putting out 60w (motor power), but LED is more efficient (the heat) and also draws less electricity to work (amp draw).
I hope I didn't too confusing or complicated there.

 

[BodgeIt]

Having looked through many different threads, I am just going to go with the recommended electrics. The guys at FT know a hell of a lot more than I do, and if they think thats whats best who am I to say different. Once I build/fly it I may make a few adjustments, but 99% of the problems will be me rather than the plane.

 

[BodgeIt]

Me again! Sorry, didnt want to start a new thread when I already had this one. My electronics turned up yesterday, so I can start building. What should I do with the battery? (3s 2200mAh). It says on the invoice the cells were checked and good, but is it safe to leave it as it is until I need it, then charge it and fly? I have been reading all these horror stories and its worrying me :/

 

[Fyathyrio]

Get a simple lipo cell voltage tester like this and verify it's at storage charge...that's roughly 3.85 vdc per cell. Doesn't have to be exact, don't get too worried if it's 3.9 or 3.8vdc. Also check the individual cells are about 0.02 - 0.03 vdc of each other. Depending on the quality of the cell, it can stay like that for a year or more as long as it's not stored in a lake or duct taped to your car's exhaust manifold. These little cell testers read off the balance tap and will give you total pack voltage as well as individual cell voltage.

What kind of charger do you have? Even an inexpensive computerized charger should have a storage charge function, but if all you have is the plug into the wall without a readout style of charger, then you really should consider getting something to verify pack and cell voltage.

Lipo cells are fine as long as you follow the basic precautions.

 

[BodgeIt]

The invoice says its 11.1v I believe, though I dont have it in front of me so could be wrong. I Have a 'proper' charger with a screen read out etc so will plug it in and see what it is.