Kellermann

My sympathies too. I had a crash on my 30% on the 4th flight afer 3 years of work, built from scratch. Rebuilt it, flew it for several weeks and sold it a week ago. Started manufacturing the model in series. Take a look at my webpage: www.marcusmodelfactory.com - Sold a few now after a few weeks of activity...see ya around guys.

Disarray

Na, elevators and servos were all still in tact. The hit was all on the nose so I could tell the failure was electronic, not mechanical.

Super08

My Feedback: (2)

That sucks. I destroyed my new Stinger just taxing around today, didn't even get to fly it. A gust caught the wing and flipped it. the plane just exploaded. We stood there in disbelielf as it wasn't going fast. After looking at it we see it was a weak area in the design made worse by no glue in the joints where it fell apart. I had re-enforced the firewall and forward fuselage, but not the aft area that failed. Now I have a story to tell about the plane I destoyed before I even got to fly it. At least I didn't put a nick in my Xoar prop.

Oh well going back out tomorrow and fly my Decathlon instead.

mschneider2005

My Feedback: (34)

Super08

If a simple gust of wind did that kind of damage, I'd be very leery of having one of those ARF flying ANYWHERE near another human being, car, house, dog, squirrel or any other living creature. Additionally, you might consider pushing the manufacturer to recall all of those ARF to prevent someone from getting hurt or killed.

It's only a matter of time before one of these Chinese Manufacturers cut the wrong corrner to save a yen and kill someone!

Super08

My Feedback: (2)

Yes we were very surprised when it happened. After we looked at it we all agreed it was a good thing it happend on the ground as it would have come apart in the air for sure. Then there may have been damage to the engine, radio and the unthinkable, people or property.

On a good note I just got back from putting 5 more flights on my Decathlon. The Fuji 43 I have on it is starting to break in now and is turning 7100 with a Xoar 20x8. It's fun making hover and torque roll at altitude. (I'm new to theis 3D stuff)

dbarrym

My Feedback: (47)

[quote]ORIGINAL: dbarrym

No test flights this weekend...[&o]

My FG36 either had the rod bearing/bushing seize or the crank pin is bent after only 45 seconds or so of running at low throttle (~2500 RPM or so). Started making bad sounds so shut it down immediately. Lots of knocking and squeaking noises rotating it by hand, pulled valve covers and valves are working and plenty of oil is visible. Confirmed the fuel was oiled properly (5% - 20/1 - Lawnboy ashless, same as I have used for break-in on all my prior gas motors).
[quote]



Just got my FG36 back, as I guessed the rod bearing/crank pin seized, apparently the crankcase vent fitting was not installed properly (I'm guessing blocked) which pressurized the crankcase preventing oil from reaching the crank pin. It's now reinstalled (I did open up the bottom of the cowl some more) and hopefully test flights tomorrow.

Barry

dbarrym

My Feedback: (47)

Was able to break in the FG-36 and got a test flight in today. The motor seems like a perfect match (I am getting 8360 RPM on an APC 18x6W) and no problem pulling through IMAC-sized loops (though, like the full scale, you need to manage energy well if you want to do consecutive vertical manuevers). The FG36 is very smooth for such a large single, and very economical - the 12 oz. tank I used is WAY too big, I got 45 minutes at mid throttle and shut down with some fuel remaining!

The rudder is very sensitive, the ailerons are heavy, and pitch is also a touch responsive at speed - again like the full scale (at least with stock throws and no expo). I will be tweaking mine (more aileron throw, adding expo to rudder and elevator, dual rates for elevator) over the next few flights to get all controls balanced in feel. CG seems OK at stock location but I need to fly it more to be sure (on vertical downlines, snaps and spins). Glides well but decels quickly at idle, does great slips - I had a 7-8 MPH near-90 degree crosswind that it handled beautifuly (but could not taxi back in!), just need to be aware/cautious of the rudder's power (I was able to snap roll it on rudder/elevator alone - it surprised me during a knife edge attempt!). You do need to work the rudder a bit in rolls and to make coordinated turns, again like the real plane. In fact I think I will add a rudder/aileron mix on a switch that can be used for general fun flying. Just a few percent of rudder should do it.

The bad news - during a slow roll it 'hung up' inverted and I had to use the rudder to roll it back level - on a shallow turn I needed almost 1/2 of the aileron throw, and the ailerons were very sluggish...suspected something was wrong so landed ASAP. Sure enough - the machined aluminum control horn on the left wing had failed! On inspection, there is almost NO "meat" at the point where the horn base tapers down into the straight threaded shaft section. See pics....

I am now replacing ALL of the horns by drilling them out, tapping for 6-32, and using sections of stainless 6-32 all-thread. The nylon horn fittings will also need to be drilled/tapped or you can get new horn assemblies from Hangar-9 or Dubro.

I would HIGHLY suggest that everyone keep an eye on these. It may be that the failed horn was drilled too deep, leaving insufficient material at the shoulder, but I am not taking the chance.

Barry

dbarrym

My Feedback: (47)

Four more flights of 20+ minutes each, the Saito sips both fuel and amps....I am really enjoying flying the SD, it is a big change from the jets and large IMAC planes I normally fly. It really makes you work for a good looking manuever, it's also a blast to just putt-putt around down in the weeds. I will now install the smoke system, and move the CG back - it won't spin upright at the forward edge of the spar, but will do nice inverted spins. The rudder is still very effective, even at low rates (3/4" throw each way) and 40% expo. I'm also going to stiffen the tailwheel springs, they are way too soft...another gusty crosswind day proved that out.

I did replace both of the aileron horns, the other horn was identical to the broken one and was likely about to fail. Replace them with something else! The stab and rudder have far less mass and area so the stock control horns are probably OK.

Ubiquitous man with model pictures attached. Very happy with my SD!

Barry

fisher1648

I've been having a good time with my SD as well. I programmed a mix so some aileron is applied when the rudder is moved and that really helps flatten and "desensitize" the rudder inputs. This airplane stands out nicely and has a great presence in the air. Low throttle passes look very scale.

I'll be inspecting/replacing the horns as mentioned !

HAppy flying, Eric

Hill202

My Feedback: (24)

Barry,

Did you have any trouble starting the FG 36? Mine can be hard to start the first time.

Thanks

rv8pilot

My Feedback: (5)

Hill 202,

Saw your post on starting the FG-36. See "gas saito" in the forum for 14 pages of info on this engine. Yes, they are hard to start cold unless you can stick your finger in the carb (we call it choking where I come from), somehow squirt some fuel in the carb, or as one guy suggested, spin the engine over with the throtle completely closed (on a big starter) with the ignition off until it pulls fuel, and then turn the volts on and crack the carb. Haven't tried the last method yet myself.

Andy

dbarrym

My Feedback: (47)

Yesterday it started OK by closing trottle and trim, ignition off, and pulling through 5-10 revolutions, then ignition on and it would start after 5 or so solid flips. First flight today and it started fine this way, but on the last 3 starts I resorted to a starter after 10-15 flips. I may richen up the idle just a touch to see if that helps.

On the rudder-aileron mixing, it has some serious proverse roll coupling to overcome..I tried a R-Ail mix and it needs a fair amount (10-20%!), plus there is some positive pitch coupling. Basically I just fly it through by hand as I found the amount of mix needed varies dramatically with airspeed...after the 4th flight it only bothered me on takeff, with the amount of rudder I needed in the strong crosswinds it would immediately take on a 10 degree bank as soon as the tail came up...not pretty. I did make a 3% aileron to rudder mix and that seems OK for coordinated turns at pattern speeds, but is not so much that you have to fight it in rolling manuevers.

The SD does make some of the prettiest stall turns I've ever seen....Figure M's at a 20' starting altitude looked sweet.

Barry

Kellermann

Guys, my .02c to the control input issue...

I decided not to use any expo on rudder on my 30% SD as the full size doesn't have it either...and I wanted to hone my fingers on the maneuvres as well. After all, the SD is called an aerobatic trainer, isn't it? The HUGE rudder is very effective, and as someone told here, on a crosswind it's hard to taxi, especially when the tailwheel springs aren't stiff enough.
But at the other hand, it becomes effective at very low speeds and you can have it tracking down the runway quite straight even at heavu x-winds.
And as also told, the Stall Turns are just beautiful en clean due to that large rudder.

As for AIL/RUD mixing, I had to use at least 30% Rudder to make beautiful coordinated, non-slipping turns. I should do that coordinating the right and left hand as well, but in this case I preferred to leave it up to the beautiful JR-8 Channel TX I use.

As for the Control Horn matter, I don't know if those horns come along with the kits, but on my prototype and also on production models I used/recommend the black, Du-Bro HD control horns or any similar. Remember, there are great forces over those control surfaces, that must be translated back n forth to the horn through a large contact area, otherwise it's prone to break, no matter how beautifully machined is that horn.


Barry, those are beautiful pix. Congrats on your lfight experiences.

Marcus

mschneider2005

My Feedback: (34)

I mentioned in an earlier posting( Post #: 635 )about the "Weird Chinese Hardware" that comes with the Decathlon. To me, it just looked weak for a 1/4 scale aircraft. I don't think I'd even use it on a .40 size trainer. I'm glad you were able to save it. It could've been alot worse (elevator)!! Here is what I've installed on both of my RC Guys SD's. It's cheap insurance.. Why risk $1000.00+ on $0.48 junk hardware?

http://www3.towerhobbies.com/cgi-bin...&I=LXGWD8&P=ML

You'll rip the control surface apart before that'll break!

jaycam

I'm about to buy the RC Guys Decathlon and have an OS 200 FS. Just wanted to get some input as to how this engine might do powering the Decathlon. Thanks very much.

dbarrym

My Feedback: (47)

I would think that the OS 200 would make similar power to the FG36 (given that the FG36 loses some power over the glow Saito 220), so I think my observations and review above would apply....

Barry

sdossett

Jaycam

My SD98 with Saito 180 is OK for power. I try to fly very scale and it lets me knife edge, loop from flat full throttle pass, wing over, Cuban-8 etc. I wish I had gone the 220 for a little extra power (it was $100) more. Not sure how the OS 200 and the 180 compare. I've tried a couple different props....16x10 too much pitch, 16X8 OK, 16X6 seems to let it run faster...18x6 in the box. Going to shop some more.

I ended up working on thrust angle with ~1/8' shim down and this let me trim w/o a lot of elevator bias AND w/o a lot of nose weight (I was up to 2 lbs. at one point). This ended up being an important part of using the 180. Build it light.

Worse part of flying this monster is that everyone else likes to sit and watch and I don't get much traffic to fly with....

Landings are a thing of beauty.

Best of luck.

Peace
Scott

dbarrym

My Feedback: (47)

Eight more flights this weekend - passed the TX around - liked and enjoyed by all.

Lost my door on the 10th flight (I did not glue in the door hinges, as i am still moving stuff around to get the CG set) - and can add that it flies fine without it, Fixed and flew again today, barely avoiding a tragedy as one of my buds wanted to see how well it hovered on the FG36..both of the 2700 5-cell bats slid into the tail, with the extensions wrapping 7 times around the rudder pull-pull cables. Did not catch it until unpacking at home!

I think I'm going to mount the rudder servo (with a solid rod linkage) in the tail as the CG can still move back some, and have also reduced the fuel tank to 12 ounces - moved the 16 oz to smoke duty. Still getting 30 minutes run time on the 12 ouncer!

Speaking of the FG36, tried an APC 18x8, went back to the 18x6W Fun Series as it seems like the ideal match. This engine is PERFECT for this plane, just the right amount of power, more so as it breaks in. No overheating problems with the baffles and exhaust duct size as described earlier.

Bumped up the aileron/rudder mix to 7% and that seems perfect, more than this and the nose drops in tight turns...less and I'm still adding more rudder in low speed turns. Great fun to do repeated touch and goes!

Barry

dbarrym

My Feedback: (47)

I gave in and have used a starter for the last 8 flights...ignition off, half throttle, turn over with starter a few seconds, throttle to idle, turn over a couple more seconds, ignition on, hit it with the starter and it fires right up. I'm about to switch to the "after break in" 30-1 gas/oil mix, after re-tuning it should make even more power.

After my initial NIB problems with the motor, it is now proving ideal for this airframe. Just ordered a 2nd one for my 150 size H9 P-51.

Barry

Kellermann

Barry
those are really beautiful flying shots of your model. The SD is a TRUE BEAUTY. No matter what size. Period.

Marcus

Hill202

My Feedback: (24)

Mine's for sale, check it out in the marketplace

http://www.rcuniverse.com/market/item.cfm?itemId=421529

Dart373

My Feedback: (2)

Hill202, why are you selling it? I am wanting one and want to put a DL50 in it... any thoughts on this? Did they fix the cowl/thrust line thing? Anybody flying one with a DA 50? It's too tought to try to read through 30+ pages...

ceiriogbach

Due to the demise of my long flown Goldberg Bucker Jungmann I now have a Saito 150 availible The super Decathalon looks like a great plane R C guys suggest a 120 could fly it I note that just about everbody is using far more powerful engines than that As a senoir/ senoir I would be happy with mild aerobatics Has anybody flown a SD with a 150 ? also does anybody remember on what page of this thread was there a discussion of aligning the engins on thr SD for side thrust

Charley

My Feedback: (2)

Hello outacontrol41,

Do you know if the G38 your friend has in his SD is the Mag or the EI version? I have a G38 Mag with a spring starter that I planned to use in the SD that I ordered last week. After reading through this thread I'm beginning to wonder if I need to rethink that.

Thanks,

CR

Bob Pastorello

My Feedback: (198)

Charley - you didn't ask me, hope you won't mind my replying. I have one of these, yet unflown (maybe today!!!), and the G 38 may just be impossible to fit and balance. It is a "flat firewall", no engine box, which means short engine is needed. There is about 7 3/8" firewall to hub face. The main issue, for me, using the XYZ 50, stock, is getting the balance. For appearance' sake, I mounted the rudder servo in the fuse to run pull pull. The single 2SA123 battery had to be mounted about 3" in front of the STAB to get the balance right.

The short fuse helps agility, but makes balance with a heavy gasser a lot more challenging.