Originally Posted by Hance

I grabbed a pic for you. It only takes a second to do and can prevent a disaster. The pics shows how it works better than explaining it really.


elevrudctrlhorns by Hance1976, on Flickr

I have 2 comments for these stand of horns ...

a) the fuel tubing is on the CLEVIS ... not the horn. The correct name for these are KEEPERS

b) These stand off horns with the threaded link - i have had these put a side load on a clevis and even with KEEPER .. caused clevis to open .. when under serious load as in high speed and the link turns on the thread ... I prefer a fixed horn with holes.

Originally Posted by solentlife

I have 2 comments for these stand of horns ...

a) the fuel tubing is on the CLEVIS ... not the horn. The correct name for these are KEEPERS

b) These stand off horns with the threaded link - i have had these put a side load on a clevis and even with KEEPER .. caused clevis to open .. when under serious load as in high speed and the link turns on the thread ... I prefer a fixed horn with holes.

A: I never said its on the control horn and B: it's not my plane

Originally Posted by Hance

A: I never said its on the control horn and B: it's not my plane

My honest apology - it was aimed more at the original who said horns .. and many after carried it on ...

And regarding the type of horn ... was not to upset .. just a comment based on something I experienced ...

I was posting when I got phone call asking if I was ready to go flying ... so closed the post and posted !! So it was abrupt !!

Sorry.

I've read .. well most of the pages and have to add some info from my experiences into FF and RC to try to help out others.
1 - Fly what you are capable of Flying.
- Sure we all start out in the hobby with delusions of grandeur, aircraft with 472 channels, details that would impress the actual manufacturers of the aircraft, Speeds to hit Mach 1 and we end up with a wonky foamie where finding a pair of parallel surfaces is impossible. While we can strive for these levels of detail, we will never accomplish them in our lifetimes.
2 - know your limits
- Are you trying to fly a 1/5th scale plane in a barn? maybe an indoor micro in a huge field with winds gusting to 25mph. Are you accomplished enough to fly in an area where there's alot of people around? Buying into the hype whether from a hobby store and their videos or from others on message boards (like this one) we can see their ideal aircraft and might think we can handle the performance or lack there of. only YOU know what limits you have.
3 - If you're going to fly it, be prepared to fix it.
Whether prop or DF, nitro or electric. When you are flying, have a means to repair items that become damaged. Murphy is an evil Sadistic man and when you think you've covered all your bases, you find there's something you forgot.
4 - Have spare parts.
- With EDF's that come stock from a retailer, most will be woefully underpowered. Many people will perform upgrades to the batteries, the motors, the ESC's and even the fan units. People will tend to throw the old parts into their field box and head out to fly. It's been my experience in the RC car realm that should you have a problem with a motor or ESC, you reach into your field box (or track box) and grab a replacement speed controller, connect it and within the first minute or so, you're putting out a fire. Your old parts will not match your upgrades. The ESC you drop in might be a 25 AMP ESC whereas your upgraded motor will draw 45 AMPS. If this combo gets into the air, it's a flaming fireball when you push the limits.
5 - Label Everything
- Nothing is more frustrating than having to sort through what wire or servo connector goes where. This can all be avoided if you put labels on things. Have an unmarked stock ESC? Use a marker and write the amp and cell rating on it when you get it. Have a worn motor? Write it's specs on the can.
6 - Throw out damaged critical parts
- With the performance capabilities of today's EDF's, having a cracked rotor can be deadly. The velocity of a glass filled plastic item rotating at 50+K RPM's and moving at upwards of 200MPH is a recipe for disaster. A dab of CA glue is not going to prevent that blade from coming out. It's simply not worth the risk of injury for "one more flight".

Originally Posted by Peacemakr40

I've read .. well most of the pages and have to add some info from my experiences into FF and RC to try to help out others.
1 - Fly what you are capable of Flying.
- Sure we all start out in the hobby with delusions of grandeur, aircraft with 472 channels, details that would impress the actual manufacturers of the aircraft, Speeds to hit Mach 1 and we end up with a wonky foamie where finding a pair of parallel surfaces is impossible. While we can strive for these levels of detail, we will never accomplish them in our lifetimes.
2 - know your limits
- Are you trying to fly a 1/5th scale plane in a barn? maybe an indoor micro in a huge field with winds gusting to 25mph. Are you accomplished enough to fly in an area where there's alot of people around? Buying into the hype whether from a hobby store and their videos or from others on message boards (like this one) we can see their ideal aircraft and might think we can handle the performance or lack there of. only YOU know what limits you have.
3 - If you're going to fly it, be prepared to fix it.
Whether prop or DF, nitro or electric. When you are flying, have a means to repair items that become damaged. Murphy is an evil Sadistic man and when you think you've covered all your bases, you find there's something you forgot.
4 - Have spare parts.
- With EDF's that come stock from a retailer, most will be woefully underpowered. Many people will perform upgrades to the batteries, the motors, the ESC's and even the fan units. People will tend to throw the old parts into their field box and head out to fly. It's been my experience in the RC car realm that should you have a problem with a motor or ESC, you reach into your field box (or track box) and grab a replacement speed controller, connect it and within the first minute or so, you're putting out a fire. Your old parts will not match your upgrades. The ESC you drop in might be a 25 AMP ESC whereas your upgraded motor will draw 45 AMPS. If this combo gets into the air, it's a flaming fireball when you push the limits.
5 - Label Everything
- Nothing is more frustrating than having to sort through what wire or servo connector goes where. This can all be avoided if you put labels on things. Have an unmarked stock ESC? Use a marker and write the amp and cell rating on it when you get it. Have a worn motor? Write it's specs on the can.
6 - Throw out damaged critical parts
- With the performance capabilities of today's EDF's, having a cracked rotor can be deadly. The velocity of a glass filled plastic item rotating at 50+K RPM's and moving at upwards of 200MPH is a recipe for disaster. A dab of CA glue is not going to prevent that blade from coming out. It's simply not worth the risk of injury for "one more flight".

Sage advice, especially #1 & #3!! I grew up building, flying and competing in free-flight. In those days, in order to compete, the AMA had a rule which said you had to be the builder of the plane you flew, in fact, my dad had to sign off saying that I had indeed built the plane I flew in the NATS, (Jr Class 1/2A FF; Sal Taibi Starduster X; 4th place '63 NATS). I can't remember ever flying an airplane that didn't crash and require repair eventually, it was just part of the hobby and was to be expected. When I began flying RC I found the same to be true, even with the building and trimming skills I learned flying free flight I learned that my thumbs were my plane's worst enemy oftentimes, and that still holds true today. In fact, some of my best flying planes have been crashed and repaired many times, and even fly better after having been crashed and repaired. I have become quite skilled at reviving what many would consider kindling, or at the very least total losses, (ain't foam grand! So easy to repair...unlike woodies!).

In a perfect world a beginner should start by flying a nice slow flying EP sailplane to learn basic control parameters, and once mastered move up to sport planes. I even think the next step should be an edf!! After building and flying, (and crashing), sports models I finally got around to trying edf's, and to my surprise they were in my experience much easier to fly than any propped plane I had ever flown. I found myself wondering why I waited so long, and decided that it was the common, (but false), perception that edf's are harder to master than propped sports planes; in my opinion it's the other way around; a good edf is far easier to fly, more predictable, more stable, and in general they are easier to fix once broken. Of course I'm not talking about a full-throttle nose in crash where nothing larger than a quarter remains, but those everyday "hard landing" crashes and mishaps that will inevitably occur with anyone who flies RC. Even the best pilots crash once in a while, and every accomplished pilot has destroyed a plane or two, (or more), and takes it in stride and just keeps going.

The only thing I would add to the above statements is safety!! Even a foam airplane that weighs under two pounds can injure......severely! A 30 ounce plane traveling at 70+ mph can really do major damage to people and property, and we should all keep that in mind when we fly. Whatever you fly, and wherever you fly, do it with the safety of yourself and bystanders in mind!

Sonny

Originally Posted by sonny1

The only thing I would add to the above statements is safety!! Even a foam airplane that weighs under two pounds can injure......severely! A 30 ounce plane traveling at 70+ mph can really do major damage to people and property, and we should all keep that in mind when we fly. Whatever you fly, and wherever you fly, do it with the safety of yourself and bystanders in mind!

Sonny

Great bit about safety. I got a phase 3 F16 as my first edf not to long ago and flew it for the first time on new years eve. Even being a foamie I am very careful about safety. I couldn't live with myself if I ever hurt someone with one of my planes. I have one flying wing that would hurt if not kill someone out right if it hit them. A 70 ounce plane going 170 miles an hour would do huge damage. Too many people treat the planes like toys and dont think about what could happen.

Originally Posted by Hance

Great bit about safety. I got a phase 3 F16 as my first edf not to long ago and flew it for the first time on new years eve. Even being a foamie I am very careful about safety. I couldn't live with myself if I ever hurt someone with one of my planes. I have one flying wing that would hurt if not kill someone out right if it hit them. A 70 ounce plane going 170 miles an hour would do huge damage. Too many people treat the planes like toys and dont think about what could happen.

Having been in modeling since the early 60's I've seen some horrific injuries to modelers and spectators both, (including me, more than once). I suspect there are quite a few beginning pilots on this thread, and those not AMA members should join, read their safety code and take it to heart, (comes with insurance in case you do happen to plow into someone and/or their property or both). RC has a bad rep in some places, and violation of safety protocols can claim responsibility for some of that problem. Our "toys" are things that can bring fun, excitement, thrills & chills, but can also cause misery and sorrow if safety isn't considered.

Sonny

What do i look out for in the characteristics of my HK L-39 (64mm)? It is stock from the box, the GREY one!! Been wanting to go maiden for a while... till i found this tread! So far i wanna do the clevis keepers, brighten up the colour & check all wire soldering. I have no funds for upgraded motor/esc, but will do cooling upgrade & cheeter holes if required. (long as some-one tells me what to do) Motor/ESC is un-marked, so watt calcs difficult.
PS: Will a long ground-run tell/warn me about inevitable overheating doom?
RC-SKILL: I think i am capable of a relatively smooth flight with long sweeping turns & long approach landing... and an abcense of funny stuff.... if i can control the flightline nerves. (even with my TB-20)

L-39 for sale... never flown! LoL

Originally Posted by georgy

What do i look out for in the characteristics of my HK L-39 (64mm)? It is stock from the box, the GREY one!! Been wanting to go maiden for a while... till i found this tread! So far i wanna do the clevis keepers, brighten up the colour & check all wire soldering. I have no funds for upgraded motor/esc, but will do cooling upgrade & cheeter holes if required. (long as some-one tells me what to do) Motor/ESC is un-marked, so watt calcs difficult.
PS: Will a long ground-run tell/warn me about inevitable overheating doom?
RC-SKILL: I think i am capable of a relatively smooth flight with long sweeping turns & long approach landing... and an abcense of funny stuff.... if i can control the flightline nerves. (even with my TB-20)

L-39 for sale... never flown! LoL

Georgy,
The plane should fly well for you based on the reviews I read. Just keep an eye on the throttle. If you run all out constantly, you will overheat the motor.
HK recommends an upgrade motor of the 2815 or 2615 with 4000KV (3s setup) Center of Gravity is 70-75mm back from the leading edge (not documenting in their manual)

I am in the process of building a 5' EDF flying wing(EPP foam). I have built about 30 pusher flying wings, but I have never built or flown EDF models. What key differences would you point out? In addition to my flying wings I have built, more than a dozen balsa buildup, gas/Electric/sailplanes.

I plan to make it 5' span, weigh less than 4 lb, dual EDF units on the top rear where the prop normally would be. How big of EDF units should I start with? I was considering 60-90mm units. I will be flying it with a DX6i, with HS 82mg servos. Is there anything else I should know prior to buying electronics?

Originally Posted by lhb009

I am in the process of building a 5' EDF flying wing(EPP foam). I have built about 30 pusher flying wings, but I have never built or flown EDF models. What key differences would you point out? In addition to my flying wings I have built, more than a dozen balsa buildup, gas/Electric/sailplanes.

I plan to make it 5' span, weigh less than 4 lb, dual EDF units on the top rear where the prop normally would be. How big of EDF units should I start with? I was considering 60-90mm units. I will be flying it with a DX6i, with HS 82mg servos. Is there anything else I should know prior to buying electronics?

Had to think about it for awhile, but here on some things to consider. Edf's are run at very high rpm, (higher than the typical pusher wing), which usually require high-discharge battery packs, and due to their ability to draw high amperage on 3S, two good esc's. I would think that two 64mm-70mm fans with 3000-4000kv motors, two good quality 40-60A esc's, (not cheapies; they usually can't handle high amps and high rpm's at the same time); genuine Hobbywing and/or Castle esc's with adjustable timing should be on your list. With twin edf's you will need a lipo for each unit, so that should be taken into account also. Running a single lipo could work, but capacity will be an issue as edf's are amp hogs, (especially on 3S). An edf takes time to spool up to flying speed and you will need enough thrust to get it moving quickly if hand launching, so AUW will be an important consideration. I'm sure there have been other edf wings built, but the only one I can remember off hand is the GP Miglet which has the fan built into the wing, but if you were going to mount your fans on top of the wing, aerodynamic drag might become an issue, (just postulating here). I have two edf's, and I love them, but I don't have that much experience with pusher wings, so maybe someone else can pipe in with some better advice than I; good luck!

Edf's are great fun, I hope your idea comes to fruition and you end up with a great flying wing.

Sonny

Originally Posted by lhb009

I am in the process of building a 5' EDF flying wing(EPP foam). I have built about 30 pusher flying wings, but I have never built or flown EDF models. What key differences would you point out? In addition to my flying wings I have built, more than a dozen balsa buildup, gas/Electric/sailplanes.

I plan to make it 5' span, weigh less than 4 lb, dual EDF units on the top rear where the prop normally would be. How big of EDF units should I start with? I was considering 60-90mm units. I will be flying it with a DX6i, with HS 82mg servos. Is there anything else I should know prior to buying electronics?

Less torque roll no air flow over surfaces. As sonny said there acceleration is lower so there is a bit of spool up delay.
Re setup any reason for twins? Twin 64s will do your 5lbs but there are a number of single 70mm can push 2 kilos or 4.4 lbs. A Single 90mm or 80mm would even be that much more fun because the wing load or carrying capacity of your 5' wing can carry both a large batt and 90.

Are you looking for speed or thrust. Manueverability and differencial thrust with the twins? Twins add more weight for their thrust and efflux. Also, if you are mounting these where the props were, props have to be wider apart, but EDFs don't, reducing the YAW effect from having them apart. If they spool up unevenly you'll notice the Yaw more.

Oh ya and sound... sound is different.

Thanks for your advice and input. A friend gave me a couple of EDF units, that are 64mm, and they say the motor is a 18L inner runner. But I dont know what 18L means. Do you know? I am trying to see if these units would work, A crude thrust test says they output 14oz of thrust each. What is your thrust to weight ratio on your EDF models? Dual EDF units are mostly because I think it would be fun to try it. I planned to connect the two motors together, and run them both off the throttle channel. With two separate ESC's motors, and batteries, how do I connect that into the receiver? I did an overhaul to the design so I am thinking I can make it lighter than originally anticipated.

Thanks.

Maybe the L18 is a Hacker motor...

I just saw these from Graupner........I'm wanting to build an EDF bird this summer.