PacificNWSkyPilot

My Feedback: (19)

LOL....

What can I say, Andy?

When I get REALLY bored I type novels. Maybe someday I'll sell a few of them.

~ J ~

PacificNWSkyPilot

My Feedback: (19)

I think we have a poster coming from the other thread who .....well, I'm not going to tell you about it because I think he will be here to do just that.

But I promise you, it was unexpected, it was right under our noses, and it's remarkable.

Until then....Off to the plane building shop with me!

~ J ~

mobyal

I swear by the JR Sport 126MGs. Use them all the time and have never had a problem so long as I use a 4-cell battery pack. Check out their specs! Apparently they don't work well w/ 5-cells, so I've never tried that. Last time I got some they were about $34 each. More than the 821s but much greater torque and metal gears.
Al

Ed

The DS-821 digitals, can be found on ebay and RCU classifides for less then $20.

I paid $75., shipping included for my last four DS-821's.

They are being sold NIB, by the people who buy Spektrum systems, and then break the sets up to sell the components seperately.

Ed

PacificNWSkyPilot

My Feedback: (19)

Now I have to go and check my 126MG's. I'm almost positive that they are made for 6Volt as well. I wouldn't even BUY anything that didn't show a rating for 6-Volt, as I no longer use the 4-cells.

Of course, that doesn't mean that I didn't have a brain fart whilst shopping one day!

~ J ~

Obee

Jimbo,
Thanks for the invite to the new thread. I will be checking in and look forward to your findings regarding the CG question and flight performance.

Obee.

PacificNWSkyPilot

My Feedback: (19)

Thanks, Obee.

Looking forward to all of it!

AJsToyz

Yep they do, I've looked at those just never got around to buying any. I've actually been beating up on HobbyCity servo's. I put them in a cheaper plane to try them, and no troubles. For 8 bucks each I figured I'd give them a go , so far so good.

Andy

PacificNWSkyPilot

My Feedback: (19)

Okay, I wasn't crazy, my ST126MG servos will take 6Volts and they give 142 oz-in of torque at that Voltage. I guess I'll have no problems at all with my elevators! Where did you read that they didn't like the 5-Cell packs, Al?

I just finished hinging up my Horizontal Stabilizer and Elevators. I checked the exact distance from the rear of the wing inside the aileron pocket to the trailing edge of the Horizontal Stabilizer, both sides were EXACTLY 35 inches. The Stab was perfectly level with the wing as well. This was the way these parts were made, I had to do nothing else to them to make them fit together this way, they were already dialed right in. Have not glued the Stab down to the Rear of the Fuselage yet, once I was was positive of the exact alignment I wanted to get the hinging done first.

By the way, when I had the Stab on the back measuring it, I used a few pins to hold it in place. I left those pins in the Stab so that I can just pin it down in exactly the same places, which I marked with a sharpie. I also took a finishing nail and went around the two mating surfaces poking the nailhead into the wood, creating lots of little extra nooks and extra surface area for the epoxy to hold on with. I had done this before on one of my SIG model builds. All those little epoxy "pins" going into the wood have to make a better, stronger bond for sure.

I had a little warp on the left side of my Horizontal Stab, I heated the underneath and pulled it down but there is still a little there. I'm hoping the little bit that's left won't adversely affect the flight of the plane.

~ J ~

PacificNWSkyPilot

My Feedback: (19)

Al, I found the article and a thread about the ST125 servos from JR. Apparently they DID have some issues with having jitters when attached to a 6-Volt pack. Not all of them, though, and JR was replacing/repairing them, making good somehow on them.

These ST126MG servos are the replacements for the 125's.

So I think we;'re okay. I'll continue to read on and see if they worked out okay.

~ J ~

mobyal

That's great news, Jim. I had gotten the info from some threads a couple of years ago. Quite a discussion on the H9 P-47 thread (their big P-47) about the issue. Since the 4-cell 4.8 volt packs are fine w/ me, I never bothered w/ 6-volt. I do have a large 5 cell 6-volt pack though, so keep us advised!
By the way, got my aileron throw/differential/flaperon dilemmas pretty well sorted out today w/ another 3 or 4 hours in the shop and three more calls to Horizon Tech Support. Those guys are great, and they really pitched in to help me get through the issues I was having. One of the reasons I'm a pretty loyal Horizon customer. Have an issue, get on the phone and TALK w/ a real person!
Enjoying following this thread.
Al

sgillmore

My Feedback: (50)

Jimbo,

Thanks for the build thread. I know it's a lot of work (and slows down the actual build) to document everything, but some of us really appreciate. I'm especially looking forward to the Syssa SAP-180 combo.

Stacy

PacificNWSkyPilot

My Feedback: (19)

Thanks Al, Thanks, Stacey.

I made a choice today and started with other parts of the build, and I'm going to have to mount the engine with the firewall vertical, because I really did not wish to stop the thread to wait for the engine. But it did not come yet, and here I am with a long weekend and the building bug has bitten.

I was able to hinge and mount all of the Empennage (Tail Feathers) today, as well as the landing gear. I also placed all the stickers, so she's looking pretty sharp so far.

Tomorrow I promised my wife a day of driving in the Hill Country, Fredericksburg and Luckenbach....yeah, the one in the song...but I'm hoping to be up earlier than her and to sneak some play time in, or at least snap some photos to show you what I've gotten done so far.

Al, Save your notes on those Ailerons/Flaps/Differential....I'm willing to bet you can save me (and a bunch of other folks) 4 phone calls to Horizon and a lot of hair-pulling with your settings listed on a post here!

I just had to slide that cowl over the front and stand back for a look before calling it a night.

This plane is about as cool looking as cool looking can get. ***DROOL***

~ J ~

PacificNWSkyPilot

My Feedback: (19)

I did want to mention one issue. The pinstriping between the colors comes off pretty easily. There are a lot of spots where it has come loose even though I applied heat. I'll probably just use the Black Baron film formula on those spots and retouch them with heat. Still, it does come off.... too easily for my liking.

When I taped the surfaces together after hinging them, when I pulled the tape off (carefully) it still pulled stripes up as it went.

~ J ~

PacificNWSkyPilot

My Feedback: (19)

Here are the results on the Vanessa Rigging that had been in the works. A Vanessa set-up uses a movable weight system where the plane is setup up with surfaces at neutral and then the CG is changed by moving the weights until it's flying at exactly the right attitude, and the beauty of this setup is that the plane can also be flown inverted, or flown in a rolling circle. Which is exactly what was done. So we know the plane is correct. But it was not done on one 'Coupe, it was done on 2 'Coupes. With interesting results!

So, here are the results, fresh-in from our "Mystery tester".

Jim, Did a Vanessa set-up on bot of my coupes and was a bit suprised. On one of the coupes the rig indicated the CG was dead on top of the spar. On the second one the rig indicated that the CG was 1/4" ahead of the spar. Both planes fly the same whether inverted or doing rolling 360's. Both planes are set up the same with G-26's and all the same internals. Other than that little difference, I would tell everyone to balance on the alum spar and "tweak it" from there.

Our thanks to our "Mystery Tester", who really did a lot of work to bring us these results.

So up until now we were going to rough it in at about 3-3/4 inches back. The test results show that our test subject planes flew best at 3-3/4" to 4-1/4".

So the factory forward range still is within our test results, but here it's at the REAR of our range.

So we've just taken the factory ranges and officially/unofficially moved them 1/2 inch forward.

On a lot of planes, that's not much. On this scale-looking short-nosed plane it can mean a substantial amount of weight for balance. I needed to move the Center of Balance forward another full 1/2-inch on my Pica Waco. This required over a POUND of weight in the nose.

I don't know what it will take to balance the 'Coupe, time will tell.

~ J ~

PacificNWSkyPilot

My Feedback: (19)

Dear "Mystery tester",

When you had the weights further back from the recommended range, did the tails fly at a different attitude?

~ J ~

PacificNWSkyPilot

My Feedback: (19)

Wow,

Guys, I'm amazed at the PM's I've been getting. I guess I really ruffled some feathers by moving the building thread over here. There are a number of people who know I came here to be able to control their antics and recreational arguing during this build, and they are PM-ing me to grumble about what they think I don't know.......... rather than posting and having it removed.

I've been polite and answered them so far, and thanked them for stopping in and reading the thread. What else am I supposed to say?

I've never been a recreational arguer, but I have some pretty sharp teeth and have never backed down easily. But with the Mods moving towards Zero tolerance on recreational arguing, flaming, and stirring up trouble in general, they didn't really want me to be the baby who went out with the bathwater, so to speak. So, I'm trying to keep things on track as much as possible, because once you take away the "other types" in here, RCU really has a great bunch of guys, friends we otherwise would never have. Guys in Calgary, Alberta, Canada can be friends with guys in Texas or Florida, or Norway, or Japan, or Australia!

We're having a good time here exploring the various aspects of the 'Coupes. Pretty enjoyable so far!

Thanks to you all for participating. It's making my build better, as well as a lot of fun.

~ J ~

OldFart1

Wandered over here as well at Jimbo's invite. Wading through about 500 emails I got while i was off in Denver (watching my Giants LOSE )

To clarify my position on JR 821's. I love them - but from personal experience don't run them on 1/4 scale control surfaces (or any other servo with a nylon or composite gearset). Love them on my .60 and .120 sized warbirds though. I know there's a zillion of you out there that run them at 1/4 scale with good results

'Coupe is almost done, installed the windows and finished programming the plane into the 9303 last night. When I get a chance, I'll post the % for Aileron Differential I used (as well as what holes the linkage is set in). As soon as the Brown Truck Airplane Parts Delivery Truck shows up with my carb spacer, I'm ready to button up the cowl. Still need to source a 6.0V/2000 mAH NiMh for the rx

No pictures from last night as I was beat - managed to remember to bring cigars, but forgot the camera

Top_Gunn

My Feedback: (6)

There's a useful thread on what makes a plane fly tail-down (or level, or high) in the aerodynamics forum. Bottom line: in theory, moving the balance point forward would cause a plane to fly more, not less, tail-down, because the wing would need to generate more lift to keep the plane from diving. But in practice, the effect would be negligible. Anyway, tail-heavy planes don't fly with their tails low; incidence is what causes that.

TooLow

My Feedback: (5)

Im the mystery tester <G>, and at the stock CG the first plane that I flew did drag its tail around the sky. It isnt like the old days freeflights that had lifting tails. When I moved the weight forward it did level the plane out in flight. With both cruse and WOT speed the tail did remain flat. The only time the tail dropped was landing just above stall speed! Its not rocket science to start with the CG at the spar and "tweak" from there. I like my birds to fly high and proud. CG moved to the rear will induce snaps in aerobatics. So It depends on your flying style as to how you trim it!

PacificNWSkyPilot

My Feedback: (19)

Top Gunn,

WRONG again. Just like the other guys that aggravated me enough to leave the other column and start my own. You newbie flyboys need to take your noses out of your books and go fly some planes, and set up some planes, and learn what the REAL world is about.

Just a question. Where is the CG on YOUR Pac aero Monocoupe? Do you even HAVE one?

You need to take your aero-babble back over to the OTHER Monocoupe thread where they cut up their planes first and then realize they should have done the NON-INVASIVE stuff before the PERMANENT stuff.

Jimbo

PacificNWSkyPilot

My Feedback: (19)

Old Fart1,

You and me both. I've got the camera on the bench now, at least. Now I need to use it! Not a cigar man, though.

I get great battery packs for a really good price at RadicalRC.com

I've never had a bad one.

~ J ~

TooLow

My Feedback: (5)

Jim, I forgot to mention the tape issueI thought that I just got a bad tape job but it seems its universal. I pulled it all off and replaced it on mine with 1/4" automotive striping tape. (has stronger adhesive)

PacificNWSkyPilot

My Feedback: (19)

May I ask, as politely as humanly possible, what the HECK is the matter with these guys and their angle-of-attack stuff? Do they think we do not have levels and Robart wing guages? Do they think we read them and go; "Heck, it's only 3 degrees off! Glue it down!" ??

Here we are, dealing with the process of correcting aspects of flight in planes that are ALREADY built, and they're telling us that our diagnostic prowess and years of experience making planes fly correctly aren't as good as their books that tell them we MUST change the angle of attack.

Now, do these guys have the vaguest idea what changing the angle of attack on a finished plane is comprised of? I mean, this plane doesn't even have a round wing tube to pivot on, it's on a flat bar spar, so we couldn't cheat it that way. Should we just break out the Stanley wood saws or the old Stihl chainsaws and start sawing away? I would have thought that the implications of this aspect ALONE would be daunting to these guys, but they seem to think that Hey, we should just DO it, because their book says so.



~ J ~

PacificNWSkyPilot

My Feedback: (19)

Thanks, TooLow.

I'm thinking that's a good thing to do. With the gas engine it should stay good indefinitely. Good idea.

~ J ~