twinturbostang

I'm putting together an UltraFly Extra 300S, and I thought I would write a hopefully detailed build thread on it. A few weeks ago, I was looking for a sport/aerobatic flyer that was lightweight, had a nice scale appearance (meaning no flaties), plenty of power, could do lots of aerobatic maneuvers, and possibly also do some 3D. I'm still rather new to electric flight, so I searched around and this is what I came up with. As it turns out, aflipz was looking for something almost identical to what I wanted. He ended up getting a 3dhobbyshop.com Sabre and his build thread is here if you want to check it out: http://www.rcuniverse.com/forum/m_3341022/tm.htm I decided to go with the Extra though, because I like the look of Extra and I also felt that depron was too brittle for me at this point. Yes, I know this model if for medium/advanced pilots, so I'm definitely going to take my time with it. I've been getting a lot of stick time in with my E-starter and I will continue to do so through the build of the Extra. I won't fly it until I feel comfortable doing so. I would rather keep it one piece than scatter it across the field!

Anyways, I just received the kit yesterday, so let's get to it! First impressions: Very nice! Kit was boxed well with nothing broken or missing. I bought the kit from Tower Hobbies, and the kit box was inside another cardboard box packed with bubble wrap. Insepction of all the parts showed good quality, especially with the foam. Looks like all the pieces will fit together really nicely. What's interesting is many of the designs present are very similar to those on my GWS E-Starter. The wing mounting design, the way the tail locks together with the fuse, tail gear design, etc. It's almost like GWS and Ultrafly are different sections of the same company! Who knows... maybe they are.

So I've started building parts of the kit. First thing I did was unpack the brushless motor. This was an upgrade from the standard brushed motor that comes with the normal kit. I wanted to make sure it had plenty of power so I went with the Ultrafly A/30/29 motor. I assembled the gear box and installed the motor. Next up was joing the fuse halves. I must say, the quality and precision of the foam pieces is excellent. The two halves fit together as good as you could ever imagine for foam. Be sure to check out the pictures below of all the parts and build progress.

Some things I plan on changing/modifying...
Color Scheme: At this point, I'm not too fond of the red decals, so I will be painting my model. I found a color scheme I REALLY like. It's going to look very similar to a kit made by another manufacturer unfortunately. Oh well... I like the way it looks so that's how it will be! One thing I don't like is the molded canopy is not clear, but a redish color to match their decals. I would have preferred it clear because the red will probably not match the paint scheme I'm planning on. So I'm going to have to either not use the plastic canopy (just the foam piece underneath), or paint it to match.

Main gear: Since it's such a great looking model, I was wanting to go with a main gear that looked more realistic. As it turns out someone has already built one that looks great: click me. I will probably do something similar. However, I'm going to also make it so I can remove the gear. Some of the grass fields I fly at do not have a suitable runway, so I want to make sure I can fly from any location I'm at.

Weight reduction: I was really looking for something in the 15oz range. This model is spec'd at around 22oz which is a bit heavy. So I'm going to try my best to reduce weight anywhere possible. For those flights with no landing gear, that will obviously help. I may eventually go with an outrunner brushless to same weight also.

As for electronics, this is what I've got planned for it so far...
Ultrafly A/30/29 brushless motor
APC 9x6 SF
2100 3S 12C lipo
Cool Running 25A esc
GWS R4PII or R6NII
(3) Futaba S3108 servos (7.6gram)
Futaba Super 7 Tx

Future changes to electronics would possibly be an outrunner brushless motor (to ditch the gearbox), and a lighter lipo to save weight (1500mah maybe).

twinturbostang

Here's some pics. Box, kit contents, and decals...

twinturbostang

Motor, gearbox, fuse halves and glued together...

pitts pilot

Mine flys great after I took out the kokam 2000 pack and put in a 1500.Two ounce less made all the difference in the world to the flying and more important, the landing of this high wing loading plane.(Park 400,cobri gearbox)E-flite gearbox in garbage after first landing!

twinturbostang

What kind of flight times do you get with the 1500 though. Was hoping for at least 10 minutes, but that may not be possible without the 2100.

It's starting to take shape now. I've got the fuse done, wing done, tail done. Just need to glue the tail to the fuse, finish the electronics, paint, etc. Even the way it sits right now, it look awesome. Can't wait to fly it! I'll have some more pictures up either tonight or tomorrow.

twinturbostang

I've got a lot more pictures. Airframe is complete. I'm now working on linkage and electronics. Haven't decided if I'm going to fly it "nude" or paint it first. I'm not going to use the included decals though. They are rather heavy. I picked up a "kitchen" scale so I can accurately weigh things now. The decal sheets weighed at least 4 ounces. I'm guessing the decals themselves (removed from the sheets) will be somewhere around 3 ounces. Too much for me. I'm estimating somewhere around 18 oz AUW before paint. And hopefully I can keep the paint below 2 oz for the grand total to stay under 20 oz. This is based on the 2100 lipo. If I throw in a 1500, that will drop it about 1 1/2 oz, but flight times will obviously be shorter. Will have to see once I get it up in the air if it's worth the trade off or not. And there are other things I can do to drop weight also. Carbon fiber rods to replace the control linkage will save about 1/4 oz. Remove main gear drops 1/2 oz. An outrunner motor may be lighter than the brushless geared motor I've got. etc.

Anyway, on to some pictures. Here's a few of the fuselage and cockpit area

twinturbostang

Wings and stabilizers. I heard someone mention the use of the plastic from a floppy disk for hinges, so I tried it out. Works great so far! Very lightweight material, yet very tough and flexible. Definitely beats the included hinge material which is more of a paper which was too stiff and felt like it would eventually tear when folded.

twinturbostang

And finally (for today), we have the completed wing, aileron linkage close up, and the tail glued to the fuse nice and straight!

pitts pilot

Mine tops out at 20oz with a 1500 kokam. I can get a good ten minutes with this pack with mostly half throttle.However the kokam is only an 8c discharge and not really the best for a brushless 400 doing lots of vertical.The red decal sheet is very nice to work with but is not good in the air for visibility.I gave mine a very thinned coat of spackle and a very light coat of spray white latex before the decals went on.The plastic landing gear plate is very weak and did not last long, same as gws.I have a thunderpower 1320 on order to see how that worksThe ailerons had too much differential for me so I bent the arms back a little so they went back and forth the same.

twinturbostang

Yeah, I was affraid of the landing gear plate. Looks identical to the one on my GWS E-Starter, and that has broken several times so far. I'm going to do a carbon fiber scale looking gear. But I've already glued the stock plate to the fuse, so I think I'm stuck with it until it breaks and then I can come up with an alternative.

As for the aileron differential, yep, I've already bent the ends of the torque rods aftward some. I could tell just looking at it on the bench that that would be a problem.

Right now the project is on hold while I work on the new brushless combo for my E-Starter. This early on in the learning curve, I would much rather crash that than the Extra.

twinturbostang

Nothing new to report on yet. I've been busy working on a new motor/battery setup for my E-starter. That's done now, so I'll be getting back to work on the Extra. Not much to do though, besides tail control linkage, electronics, and paint. Oh, I don't have the esc yet though. I've been waiting for the Cool Running 25A, but it looks like it's still on back order. I may have to just get a Castle Creations if they keep pushing the availability date back.

TManiaci

My Feedback: (6)

'Stang,

Looking good!

Pay close attention to that canopy magnet. It doesn't work so well if it is not "touching". Ours came off on the second flight, others have had the same troubles. I put in two extra magnets on either side to kepp it shut. Clean them off every time you put the top on, they pick up little metalic grit from the dirt and such, then they don't make good contact and it pops off easy.

This thing is not a floater, so it lands hot. You have to fly it in. It also has a nasty snap tendency, so use lots of expo on the elevator and go easy on the stick at low altitude. This bird can get away from you really fast.

Good luck. Now that you E-Starteer is dead, I'm sure you'll have this ready to fly soon. That Torando might work well in this plane... and save weight too losing the gearbox. Made a huge difference on ours.

twinturbostang

Yeah, I noticed that if the magnets are not touching, they don't "stick" very well. I was thinking of doing what you did to make sure it stays put.

I may have to change fields for this one. There's another one at work that's much larger. But there's no suitable runway. It's all grass field. Can this plane be flown with no gear? Hand launch and then land in the grass with a prop saver?

I had considered that, but didn't know if it had enough power for the Extra. You think it has enough? I've got the Ultrafly A/30/29 brushless motor (geared) I was going to use. And the thing is... if I switch to the outrunner, I need to use a dowel/plate mount which means the motor stick gets chopped off short. Which also means there is no going back to the geared motor setup. I'm a little worried about doing that. Once the motor stick gets glued in and then cut short, there's no going back.

Brian

twinturbostang

Oh btw. How did you secure the battery in your Extra? I want to make sure I don't have any more problems associated with keeping the battery IN the plane! lol

TManiaci

My Feedback: (6)

We were kinda stupid about battery retention. It never did bite us, but we had a fat 2000 mAH and it fit snugly in the front cavity. I'm sure if I had worked hard hovering (not on this bird yet) it could have slipped back and out.

Getting CG forward enough with the outrunner was a challenge. We saved so much weight with the outrunner install, the battery had to pushed in all the way to the back of the front firewall, too a little carving to get in up there.

Not sure if the Tornado 400 will do for sure. Can you get a thrust measurement off the E-Starter? Without wattage measurements, can only guess. This plane will come in at 24-26 oz's with inrunner and 2000-2100 mAH. Ours was 22 oz's, and still very heavy flier. Wing loading is not very good. If you target only decent sport flying, you'll need 20 oz's thrust (weak, but flyable), Should fly very well on 30 oz's or better.

twinturbostang

I don't know how much thrust I was getting with it installed in the E-Starter. Well, it definitely had more than 18-19 oz. The E-Starter weighed a little over 18oz, and holding it vertical with it on full throttle, it was trying to pull out of my hands. So I'm guessing at least 19-20 oz of thrust. I'm working on building a bench tester for measuring thrust. But right now I don't have a 3S lipo to test it on anyways.

As for Extra 300 weight, it looked like it was going to be somewhere around 18 oz with a 2100 lipo, but before paint. Not sure why mine is lighter than yours. Oh, this is with the Ultrafly A/30/29 brushless setup. Did you start off with that, or the stock brushed motor? Could be the brushless (even though it still has a gearbox) is lighter than the brushed setup. If I ditch the landing gear and go hand launch, that saves another 1/2 oz. And since my 2100 Dymond blew up, I'm thinking of starting off with a 1320 Thunder Power, which should shed another 1 3/4 oz. With paint, AUW could be somewhere around 17 1/2 oz. That would be great if it ended up that light. I think it would handle low speeds much better then, and probably be more forgiving for a newb (me).

twinturbostang

BTW, is this the gorilla glue you were talking about?
http://www.gorillaglue.com/home.htm

TManiaci

My Feedback: (6)

Gorilla Glue... yes, that's the stuff.

TP1320 mAH... that battery is only good for 15 amps max... 15 amps will only make about 140-145 watts. Not enough. You should be targeting at least 20 amps to get reasonable power (wattage/thrust) to pull around a 20 oz plane with any authority. My guess is the Tornado was drawing just under 20 amps to make that hovering feel on an 18 oz plane. A 2100 mAH battery is right for a plane of this size/class... don't sarifice weight and buy a battery that won't deliver enough power, in my opinion.

We went straight to the outrunner. I'm not sure how you managed to keep it so light, puzzling. That's a huge difference. hmmmm...

twinturbostang

The TP Pro Lite is rated at 13C, which is over 17 amps. But yeah, if it's going to be pulling 20 amps or so, that's still too much. Point taken.

I don't know. I'll weigh it again tonight. I'm pretty sure I took everything into consideration before. Airframe, motor, prop, esc, battery, receiver, servos and linkage, landing gear, etc.

TManiaci

My Feedback: (6)

Well, the AUW is always greater than the sum of the components by some margin. It is rare to hit the published weight on a model, much less end up below it, unless you have taken substantial measures to reduce mass content. Published weight is 22 oz's, and we hit that number with weight-reduction in a couple areas. That was a) Outrunner installation and b) cut out canopy foam. We did some other things too, but I can't remember without staring at it again.

twinturbostang

Hmm. Well, I'll measure it again tonight. I may be off by an ounce. But I can't see being off by 3 or so. Oh, I found that the foam canopy weighs less than the plastic portion. So it's better to stay with the foam. The plastic looks nicer, but weighs more.

twinturbostang

Ok, here's what I've got...

Plane w/ linkage, servos, canopy (foam one), cowl, etc. - 256 g
Ultrafly A/30/29 brushless w/ motor stick and gearbox - 78 g
APC Prop - 10 g
Prop nut/adapter - 4 g
Prop spinner - 10 g
GWS 4ch receiver - 6 g
Assembled main gear - 14 g
Thunder Power 2000 3S Lipo - 120 g
Deans Ultra connector for battery - 6 g
Castle Creations Phoenix 25 ESC - 17 g
ESC-motor connectors - 5 g

Total - 526 g (18.55 oz)

Now, keep in mind this is before paint or decals. I don't plan on putting any of the included decals on though. And they DO seem a bit heavy. I plan on painting it, but it will mostly stay white, so I'm hoping to keep the paint below 1.5 oz, which would mean the AUW would be right at 20 oz. Also keep in mind, the airframe is completely built, so there's no more added weight from glue. Subtracting out the main gear and prop spinner (for hand launch and switch to prop saver), that drops the weight to 502 g (17.7 oz). Again, that's before paint, so using the same 1.5 oz figure, that would be an AUW of about 19.2 oz.

I think I was very thorough, including all connectors and stuff. But if I've forgotten something, let me know. Oh and there are still things you can do to reduce weight, like switch to carbon rods for linkage and other things like that. The metal wire included weighs 10-15 grams probably.

aflipz

My Feedback: (10)

By the way twinturbo, more incentive to go castle creations over cool runnings...


the new phoenix 25 has a 3 amp bec! Look for the yellow sticker on the front of the bag... old bec was 1.5 amps; very limiting.

TManiaci

My Feedback: (6)

'stang...

Eehhhh... don't count your grams before they hatch. We put in the Maxi 09, and it's only 47 grams. We have a over an ounce less motor in it than you with your inrunner rig, and still came out 22 oz's. Maybe foam density is different, who knows. I'll be anxious to see you AUW when it's ready to fly... and check your scale with a known mass. Something doesn't add up.[&:]

twinturbostang

Yep, Cool Runnings were still out of stock and not responding to my e-mails, so I ordered a CC Phoenix 25. Should be here tomorrow. It's 0.2 oz lighter than the Cool Runnings too. Every little bit helps! Oh, and since my Dymond 2100 pack self destructed (that darn gravity thing!), I went with a TP 2000 pack, which is 15-20 grams lighter (I think).