27% 170B build

[170C]

Aryana, I am impressed that you have the skill and tenacity to take on such a project. ( I sometimes had issues putting together the old plastic models as a kid and have them look as they should) I enjoy watching your progress and look forward to seeing a video of your first flight.

Those aren't compression springs on the tailwheel are they Wonder what color you will paint it

[Ryan Smith]

Minor gripe here Arash, and it's probably nothing because I can see how you could verify it.

The elevator servo horns being offset to the front bothers me. I hate offset horns because usually it's very difficult to ensure that the horns are the same angle. While you have the benefit of the servos being mirrored right next to one another, mitigating any misalignment, you've got a powerful enough transmitter to set the arms parallel with the hinge line and simply decrease your down elevator travel as well as tailor the expo to your needs. I couldn't stand mechanical differential on airplanes when I developed them for Horizon because I had to use a Y-harness on the servos, so there was no independent adjustment short of pulling servos apart and re-indexing the gears which is a shot in the dark at best. Also, I would be hesitant to use a spring-loaded servo saver connector on anything, much less an airplane this size, particularly the elevators. When loaded, they can move independent of a servo input (obviously)...not something you really want. I'd replace them with ball links and have a smoother elevator linkage that's infinitely more secure.

Please bear in mind, this is coming from a pattern flyer, who is more anal retentive about setups than most other pattern flyers are. I'd hate to see you have trouble with this beautiful airplane, especially considering the fact that you're burying servos in the fuselage.

[Ryan Smith]

You've got a DX8, correct?

And my apologies on the mis-identification of the elevator servo hardware. I have never used those before! Good choice.

[Ryan Smith]

Or get a JR XG8/XG14 and get XBus and telemetry.

I've got a DX7S that I'll never use again that's brand new and needs a good home. If you're interested, it would save me from moving it. I'd honestly give the thing to you. Since I work(ed) for JR and am sponsored by them, I advocate strongly for their new systems, but being that they're not compatible with any of the Horizon BNF stuff, I can see where that's a turn-off. The XG11MV is a sweet radio, and is module based so you can still use it with BNF stuff with a Spektrum module, but it's probably more than you'll need unless you're planning to get back into it heavily.

[170C]

What did he say

[Ryan Smith]

I would eliminate the optical kill...with good throttle setup you can use a kill switch to close the butterfly off completely. I've never used an optical kill, even on a gas airplane. I'd rather save that extra channel for running separate elevator servos. Everything else looks good to me.

To answer your previous question, the Hitec programmer only works for programmable Hitec servos. Expert makes a reversing Y-harness, but again, I'd do everything in my power to not Y elevator servos together. I'd even suggest rotating one of the elevator servos 180 degrees so that you could use a regular Y harness.

[Ryan Smith]

The JR servos were never programmed "reversed". They were actually hand-modified by the service center by resoldering some wires and swapping them. That's the only difference, and that's why they are no longer offered. You can either use the reversed servo, or reverse the servo itself physically (rotating 180 degrees) to achieve the same effect. Most H9 airplanes and E-flite airplanes actually don't have symmetrical flap and elevator servo geometry, if you study closely. This is to allow for guys to use a DX5e on almost literally everything they make.

The flap system programming will allow you to slow the flaps down. Easy to do and accessible.

Is your address in the directory still correct?

[GAHorn]

Or get a JR XG8/XG14 and get XBus and telemetry.

I've got a DX7S that I'll never use again that's brand new and needs a good home. If you're interested, it would save me from moving it. I'd honestly give the thing to you. Since I work(ed) for JR and am sponsored by them, I advocate strongly for their new systems, but being that they're not compatible with any of the Horizon BNF stuff, I can see where that's a turn-off. The XG11MV is a sweet radio, and is module based so you can still use it with BNF stuff with a Spektrum module, but it's probably more than you'll need unless you're planning to get back into it heavily.

Is this another "turbo-entabulator" skit?

[Bruce Fenstermacher]

The JR servos were never programmed "reversed". They were actually hand-modified by the service center by resoldering some wires and swapping them. That's the only difference, and that's why they are no longer offered.

Holy cow I can not believe what I'm reading. They actually hand-modified the servos.

In the old days we hand modified servos all the time in the day of Kraft radios when the KPS14 was the "small" servo and the KPS15s were the big brutes. This was before the magic reversing switch on the servo was invented. Disassemble the servo and reverse the pot and motor wires and reassemble.

Here is my first RC radio. A Sport Series Kraft 4 channel anolog. No servo reverse, no servo travel, no dual rate, no expo. Cost $250 in '82. This was the radio I used to learn to fly my first RC helicopter, a .28 size GMP Cricket, fixed pitch machine with no gyros what so ever.

Kraft 4 channel analog with receiver, 550mah nicad battery and a s-14 servo missing the servo arm.

But you guys might not have even been born when I was flying this in the early 80s. You don't know how good you have it.

[Ryan Smith]

I was born in 1986, most definitely not. I've got a JR PCM10 transmitter that's almost as old as I am. I believe that transmitter was offered in 1989.

For those of you that are lost with all this talk of transmitter features, please reference the clip below. It pretty much sums up the entirety of R/C modeling.

[youtube]http://www.youtube.com/watch?v=4xgx4k83zzc[/youtube]

[GAHorn]

Gaawwwdd! .... and I thought only bluElder was old!

And Bruce, that 1982 $250 was equivalent to $1250 today.

[Bruce Fenstermacher]

Do you still have that Kraft radio? It's pretty cool, and I hope you do

Arash, that picture was just taken in my basement yestarday. I should have a 6 channel version of it as well somewhere. It is a 72 mhz radio that should work with fresh nicads and the gimbal pots cleaned. But why would I do that when a fresh radio is just a bit more than the nicads would cost. I've rarely sold or thrown any thing away of this sort ever so it is likely, my wife or kids will get the pleasure but not for a long long time I hope.

And Bruce, that 1982 $250 was equivalent to $1250 today

Yes it is George but $250 will buy you a pretty good RC system today in fact it will buy you things we only dreamed about in the 80s.

Gaawwwdd! .... and I thought only bluElder was old!

In RC years I am as old as BL however I'm not as old as those guys in the 50s 60s and 70s who flew with vacuum tube radios and rubber band powered escapement servos.

As stated by others, I'm glad Arash is sharing this adventure. It is a lot of fun specially for those of us who have been there. I remember building my first RC trainer a Bridi T-20 on my kitchen table. That lasted a day till I was moved to the extra bed room on a card table in our 2 bedroom efficiency apartment. And George $250 was 2-1/2 months rent at that time.

[johneeb]

What is the purpose of the J bolts?

[Ryan Smith]

Get another set and pressurize the tailcone.

It's looking more and more amazing each day!

[canav8]

Aryana,
Take a piece of phenolic and a dremel tool to make your yokes. Phenolic is available at spruce.