Sorry Folks. I was getting lost looking for info in the other thread.

Mine is doing great. Still have not weighed it or know where the CG is, however I started adding tail weight. The 2-56 rods bent up like crazy, but all knew that would happen. CF 2-56's work fine, no need for 4-40's. Put on some trick CF gear to give it all cool looking stance along with a Sullivan tail wheel.

Anyone take off the wing tips yet. It made my Madness fly much better after I did.

I am not happy with my motor. OS 91FX. With the baffle out, the performance was acceptable, however it has a SERIOUS fuel draw issue and over heat. So I put the baffle back in, so the motor would continue to run.

I know I'm picky, however I have met several of you that are as picky as me :-)

WIth a 15-4: Hovers like a dream at about 1/3 throttle, EZ to hover and backs down nicely. It takes WAY too long for it to spin up. Very sluggish pulling out.

14-4: Spins up fast, but takes too long to catch when backing down.

14-6: This was the best, however the motor stumbles transitioning from idle, like when popping up. Its like the low end is rich, but I went both ways and couldn't get it better.

I wish APC made a 14-5.

I think the motor for this plane is the OS 91 Heli motor, with a real carb. I don't like stroker motors.

Has anyone tried a Nelson muffler on the 91? Pipe or Moose can won't help from zero airspeed and full power, so those are out.

Any other prop ideas or motor ideas? 30% fuel, new carb, custom made bolly CF prop or am I gonna have to bite the bullet and re-motor the plane? I may need to change my thinking with strokers.

What other Mods have been working for you.

There are several other things I'm going to try, but this weekend was the first time it didn't rain and the motor ran consistent. Changing the incidence on the wing by shimming the wing saddle may take away much of the KE coupling and the tips may have to come off.

What else is working for yall?

I Just took the wingtips off last week, I flew it Friday for the first time without the tips and I liked the spins better, but I couldn't see any other difference with the tips off. wing rock in the elevators and harriers was about the same as with the tips on.

I've got the CG back at 6", I'll be moving it back a bit more.

The other mod I've made is I've added a strake just forward of the fin. I'm hoping this will improve the pitch to the belly with rudder input. Here's a picture of the mod:



David

Tony, if the engine (OS .91 FX) is relatively new, you could probably return it to Tower (if that's where you got it). A buddy of mine had probs. w/ his and Tower gave him a FULL refund. I think they are aware of this prob...Steve

Tony, I think it is time to go 4 stroke !
I'll let you fly my Showflyer and then you will have a feeling for the awesome Saito 100 ! Should be ready to fly this weekend.

I've got a great name for your U-CAN-DO-3D...

...Y-NOT ...HAHAHAHAHAHAHA

I'm glad you started this thead! Finding info like this in the old thread was too time consuming.

I'm assuming the 2-56 rods you're having trouble with are the aileron rods, right? I haven't had any problems with the 2-56 on the elevators, but I went with 4-40 on the ailerons. Rudder is a pull-pull with the servo on the bottom of the fuselage.

My UCD came with about 1 degree of left thrust built into the firewall. A 3 degree Ernst thrust plate was used to get back to 2 degrees of right thrust.

For now my UCD is flying with a ST 90. The only props I've tried so far are the APC 14x6, Zinger 14x6, Rev-Up 14x6, and Zinger 15x6. Out of these props, the Zinger 14x6 is my favorite due to the faster spool up time of the wooden prop. I've got some APC 15x4 props on order, but I'm concerned that the slower spool up time of the 15x4 might be unacceptable. I sure wish APC made wood props!!!

Experimentation with a MCP on the ST 90 is still ongoing. The best results so far have the ST 90 spinning an APC 14x6 at 11,700 which gives the UCD pretty good acceleration out of a hover. The MCP has improved the power, transition, and fuel draw over the stock muffler, but transition and fuel draw issues still need some tinkering. Pehaps an OS 7D carb might cure these problems.

I'm debating on trying a Perry ocillating pump to see if that helps the fuel draw, but once the MCP gets dialed in, that might not be necessary.

CG is now at 6.5" and I like it much better than the 5.5" and 6.0" that I started with. But to get back this far, I had to replace the 120 size motor mount in the kit with a GP 60 size motor mount, and then push the ST 90 back as far as possible. And I don't even have the cowl installed yet, which would add more nose weight.

I'm wondering if a Saito 100 would be better than the ST 90 w/MCP in a UCD. I think the Saito 100 would be about the same weight as the ST 90 w/MCP, and maybe even lighter. But my buddy's Saito 91 falls way short on power compared to my ST 90 w/MCP. This has me worried that the Saito 100 still might not be enough power once you start to really throw the UCD around.

I've also considered an OS 108 or a TT 120 since their weights are identical to each other. But these two engines would add about another 1/2 pound of dead nose weight to the already too nose heavy UCD. The power and throttle response would sure be nice, but I'm not so sure the weight penalty would be worth it.

is there a web site to look at this gear and/or purchase it...i am assembling the flip3D and another cool looking main would be nice...

www.troybuiltmodels.com

The trick gear? I DONNO???? I got them from some guy selling them at Joe Nall this year. He was going to start making gear, didn't have a card and only had a few pieces there. I should have bought more. So if anyone knows who that guy is, let track him down and get some more of his stuff. I am going to order a set of Bolly CF gear and put these on my Flip.

YES!! The stock rods on the ailerons bent up like crazy. I have CF 2-56's going on. The rudder rod, LOL. Well.........its almost insulting that they put a 2-56 on that rudder.

I just put a couple of washer behind the motor mount for the thrust line, I never checked the firewall, however on a plane like this, it should have been built into the plane. Mine may need another washer.

The motor issue: Nothing wrong with the motor, 99.5% of the people would be more than happy with its performance. But us 3D people................become a tad more demanding. At only inch's off the deck, I need power NOW!!!!!! not a half a second from now.

I have a 7L carb I need to drill and tap.

I know what will work, is that Heli 91. A buddy just ordered one for a UCD, so we will see how it works.

Fuel, plug and props. Just gotta find the right combo.

Ok I have read threw the other thread about 5 times and I have contacted YS. I still can't decide so I will ask here.

I am fairly new to 3D and I want to HOVER!

I am real close to buying a YS 91fz but I keep thinking that the saito 100 or maybe a 120 in ys or saito would be better. I have heard that the 100 is lighter but the ys 91 has better transition and more power. I have also been told to get a 120 for the added power.


Is there really a need to put the tank on the CG. I like the idea, but does it cause a balence problem?

If I go with saito I would have to have a pump to put the tank on the CG and YS I would not.

I have heard the ys 91fz will hover this plane at half throttle, is this better than the saito 100 is that good enough?

Help I am tired of all these conflicting opinions, please someone what is the best motor for this plane?

So far this is what I have gathered:
YS 91fz-- Hover at half throttle, more power than the 100, comparable to most 120s

Saito 100--Light, several threads stating this is the perfect combo, have to spend more money on a pump to put the tank on the CG

120 YS or Saito--too heavy causes the adding of tail weight, some say the power is too much, some say it is perfect, the ys is discontinued and both cost more for unknown added value.

YS 140fz--most would say it is way too much for the plane, but have seen a couple of people use it and seem to like it.

I maybe crazy but please any info could help this decision be made.

Thanks all

carltonck,

I've been flying my UCD with the YS91FZ. I have a little over two gallons through it and it keeps getting stronger. When new, the engine turned a 16x4W APC at 9300 and would hover at half throttle. By the middle of the second gallon the engine was turning a 16x6 Bambula or 15x8 Menz-S at 9200+. It will hover at a little less than half throttle on either of these props. On the other hand, at full throttle, it doesn't leap from the hover. It does climb with some authority, and accelerates going up, but I could see where more power might be a good thing.

In my opinion, the extra weight won't hurt you. With the 91, and the CG back at 6" the plane feels VERY light in the air, so much so that I run spoilers for landing or it just floats forever. The plane is hard to stall, it's reluctant to snap and needs to be coaxed into a spin.

If I were to do it again, I'd go with something stronger, even if it were heavier. When I first heard of guys running the YS 1.40DZ in this plane I thought they were nuts, but I'm not so sure now. I'd sure love to try a DZ in mine.

As far as putting the tank on the CG goes... it doesn't cause a balance problem. I've got a 1000 mah 5 cell battery in the tail and the tank on the CG, and I'm still going to start sticking lead on the tail to move the CG back a bit more. I'm figuring two to three ounces will get it there.

David

Take the words "hovers at half throttle" with a grain of salt. Throttles are NOT linear on R/C airplane engines. When the throttle stick is halfway between idle and full, the engine is running at closer to 3/4 throttle. This is why the YS hovers at "half throttle" but barely pulls out at full throttle.

Help I am tired of all these conflicting opinions, please someone what is the best motor for this plane?

Welcome to the real world, and R/C aircraft. Everyone's experiences, and perceptions are different, and that doesn't even take into account environmental differences such as atmospheric conditions or manufacturing variations in engine and airframe. If you end up with an unusually light airframe and/or an unusually strong engine, the plane may be absolutely amazing. However, if the materials coming down the assembly line happen to be on the heavy side and/or the engine is a bit tired, the airplane may be a total dog. In other words, it's the luck of the draw.

There is no One True Best Motor(tm) for the UCD3D, as there is no One True Best Motor(tm) for any airplane.

I know all you need is one more opinion, but I would probably go with the YS91.

Saito 100 on mine and would not change it for the world. It is light, powerful, great throttle response, easy on fuels, quiet, and cost less than a YS. The only advantage I can see from the YS is fuel tank location. I've had a YS before and it was really picky. To it's credit, I didn't give it much of a chance before I yanked it off......

The real issue with this plane is GP's lousy packing. My first UCD was totaly perfect in every way....right up until my buddy, who was flying it, said "Watch this....."

It has now taken 2 kits from GP to get a good one......and it would need to improve a bit to be considered good......there is something rolling around in the wing of this one.....I can't feel any brokn ribs (unlike the first replacement kit that had 7 or 8 broken ribs...)

Of course when you talk to them GP, it is not thier fault......

Pug

Saito 100 is best for this plane, not so much because of power, but because of its light weight, which enables CG to be moved back to 6". It has enough power to do what the plane is designed for, but not like a rocket. I have Saito 100 on my UCD as well. With the 15x6 prop, it hovers at exactly half throttle stick as well, but its rpm is more like 3/4 of peak. When I go to full throttle, it would pull out, but not jump out.

Pugs, what prop do you like most with your Saito 100 on UCD? I had APC 15x6, and it has pretty good power w/ 9500 peak (10% nitro), but throttle response is not instantaneous. I switch to Pro Zinger 15x6 to improve throttle response due to its light weight, but rpm dropped to 9300 peak (15% nitro). The engine seems to be struggling sometimes during pull-out and inverted flat spin. It seemed like with the Pro Zinger, it would lean out in the air, although I richened it up on the ground by 200 rpm. I haven't tried the 15x4W yet. Hopefully I will get over 10k peak with it, and decent throttle response. I tried the 16x4W, and it was just too heavy: it would not idle, and spool up was like 1/2 second.

I wonder if the OS 91 Surpass's throttle response is better than the Saito 100. But to get enough thrust with Surpass 91, 15x4W is probably the only choice.

People have complained about using 15" prop w/ the 91 2 strokers as been unresponsive. 14" props is not quite enough for this plane, so 91+ 4-stroke is a good start. I wonder how well the MVVS 91 does w/ 15" props? It has the power of 91 FX. If it turns 15" prop w/ good response, it might just be the perfect engine for this plane. It can be turned into rear exhaust. So if its stock Pitts muffler is used when it's configured as rear exhaust, the exhaust can go into the exhaust channel at the bottom, and keep most of the plane clean.

Any engine that's heavier than 25 oz including muffler, you will need to put the battery/weight at the tail to get good flying balance.

I like the APC 16x4 W......it takes a bit to spool up but it a very good all around prop.....not a big tach head so can't give you any figures.....but I really like it......

Pug

MY UCD STORY


I HAVE UCD THAT I STARTED OUT WITH A OS 91 FX.
THE ENGINE HADE GOOD POWER BUT A LEAN MIDRANGE WICH IS NOT GOOD FOR HOVERING OR 3D FLYING. I DECIDED TO INSTALL A NEW SAITO 100 AND IT PULLS BETTER THAN THE OS AND THROTTLE RESPONSE IS AWSOM. HERE IS SOME OF MY PARTICULARS.


ENGINE SAITO 100
PROP APC 15X4W
FUEL COOL POWER 15%
WEIGHT 7.5 LB
CG 5.75"
ALTITUDE 1000 ASL

PS: MECAM, HOW DO YOU KEEP YOUR WINGS FROM ROCKING DURING YOUR PARACHUTE ? I HAVE TRIED 100% SPOILERON.

I think the YS 110 in this would be killer. Its same size and weight than the YS 91, just more va-va-voom.

Yeah, call me a "motorhead" :devious: , but there's nothing like having "bail-power" confidence, in a vertical attitude, 2ft off the ground. X-tra weight, not an issue w/ the Saito's lgt. weight (less than the YS 120/140) and the UCD's lgt. wing loading. The only drawback I would assume woud be it's fuel consumption, (which would probably be just a little more than any .91-2cy) but w/ this diplacement you could run as low as 5%-10% ntr. at a low throtle setting. Furthermore, you get to swing a big, fat prop to cover all those thrust vectoring surfaces. Will it work? Sure it will. I've got an U-Stick .60 w/ an OS1.20FSIII (which is also heavier than the 1.80) that I hover/TR all day long. Pogo's up & dn the runway are a blast. Punch it and GO! Tail weight?, You bet!!, try 3-1/4oz's not an issue. And I'd like to add a little more for some added fun! Anyway, that's the powerplant I'll be usin' in mine, so there! :bananahea

Do you think a little bigger gas version of the u-can do plane will appear on the market??? Thanks Captinjohn

captinjohn,

It's called Diablotin XXL

seanychen: Tell us more about this plane. Thanks Captinjohn

http://espritmodel.com/

Wingspan:
102" Length:
100" Weight:
21 lbs. Channels: (4-5)
Rudder/Elevator Ailerons/Flaps/Motor Engine: 3.6-4.8 glow

Diablotin XXL
$879
(ARF Classic-almost ready to fly)

$759
(ARC Classic-almost ready to cover)


At this moment the biggest Diablotin from huge Fun-Fly family of Diablotin models. This model is really show stopper, fully 3-D capable. Specially designed for aerobatic 1 scale 3D flying. Extremely light all balsa/plywood construction. Diablotin XXL comes in blue/yellow or red/yellow transparent covering.
(Always ask for color availability)!!!

Special Features:
- Tight covering with all seams hand-sealed
- Elegant gel-coated yellow fiberglass CAP style cowl and wheel pants
- Clear canopy
- Ready-built balsa rib/spar two-pieces plug-in wing and stabilizer
- Pre-cut hinge pockets
- Transparent Ultracote on wing and balsa tail parts
- Includes all necessary hardware and CAD detailed drawing
- Aluminum landing gear
- Elevators servos installed in the stabilizer
- Two servos per aileron


Airfoil : Special
Wing area :
Wing loading :
Empty weight :

When I think "bigger version", I don't think "BIGGER PRICE" by that much. That much money is kind of crazy for this type of model IMO. I would rather put that into a 30% - 35% airframe.

Dale

Try the World Models "Fun World 3D" for $250 then. It is like a 120 size version of Something Extra w/ quad flaps.

http://www.theworldmodels.com/funworld3d.htm

From the music, you can tell it's Chinese.