Allright, i suppose you're right about the bolt. I pretty much knew it myself too, it just seems kinda scary. I know the bolts are very strong in tension, i was more concerned about shear forces. But i guess the only time there will be shear forces is in a crash, in which case it's almost always better for the bolt to break anyway.

Hey, thanks a lot for your info guys, it really is invaluable to me, especially since this is my first 'real' kit. And i'm sure i'll be back with more questions before i'm done. This thing is starting to look like an airplane, it's exciting.

DGrant,
I just made my first set of CF landing gear. I have been unable to find any info on the actual number of layers of cloth. (I also forgot the part about PVA I tend to go on the light side (a 180 swing from 2 years ago!) and went with 7 layers that taper to 5 layers at the ends with 2 layers of 3/4 oz glass on the outsides.
BTW, nice plane!

Well, i've got it pretty much all framed up. It's a miracle that i haven't destroyed it yet. I have not developed the cautious habits that i think are necessary for balsa modelling. I always find myself making quick movements reaching for a tool or something and knocking things around. If this plane gets airborne before i knock the tail off or step on it i'll be happily surprised, lol.

Now i'm waiting for my engine to come in and i need to order some covering supplies. Since this is my first covering job i need to get an iron. I think i'm going to get the trick Century 21 iron with the built in thermostat/temp control function. Sounds pretty handy. All the little things are really starting to add up costwise.

By the way, i think i somehow managed to actually build it straight! That's gotta say something for the kit! If i can build it, anyone can. The only part that really gave me much trouble was the wing mounting system. I didnt quite understand/couldnt quite visualize what was going on, untill it was nearly complete and i had messed it up just a little bit. I think they need more clear directions and more pictures for that part of the assembly. Otherwise it's great.

Here's a pic

Hi MiL, Your plane is looking really good and in short order too, didn't take you long at all to get this far. Your about half-way I think. I told you the wing-mount would be a trip. When it's done it comes together nicely though.
21st century is the best iron out in my opinion, I would bet in most everyones opinion.
For the cowling, if your going to use the ABSplastic, there's putty that called "squadrons". You can get it at your LHS. It comes in white and green, obviously you want white. It will totally work for the seams, and you will never know they were there. I sure hope your cowl lasts longer then my first plastic did. StansFiberTech's is about $55 or so for the cowling and wheel pants. If your not going with a big motor, you will get alot more out of your cowl then I did.
It is a nice kit, and well thought out. I'm not sure if your aware, it was designed by Mike Cross, he is husband to AnnMarie Cross that helps us out in most radio forum, and she is product support manager for GreatPlanes. They both also designed the 33% Extra from GreatPlanes. I have my eye on that one. After I finish my Midwest 27%, just seem to want bigger these days.
Anyways,,,,,,,,Good Job man.....your well on your way to a very nice plane. Congratulations.

Hi guys!

I've duplicated the Extra ABS cowl and wheelpants in fiberglass. If anyone of you is interested, you can get one set. CF landing gear is an option too.

If your're looking for Stansfibertechs' one, the price tells you it should be made out of gold.

Sašo

Ok, i'm getting closer... mostly been waiting for the last several days. Waiting for my motor to come in, and for my covering and iron to arrive. I like to support my LHS as much as i can afford to, and bought pretty much everything up untill now from them, but they have a somewhat limited selection of ultracote and have it priced a little high, and the iron priced way high, so i sent off for those items. It all should be in tuesday, motor and finishing supplies. So i've been doing some final fit and finish things, sanding, and installing radio components.

I have a question about preparing for the covering. I've sanded the airfram down in 3 stages, ending at a finest of 320 grit. Is there anything else i need to do?

Also, where might i find some stickers for the sponsors that are named on the aircraft? Especially the big "BF Goodrich" on the left wing and "Aerospace" on the right. Hmm, it actually occured to me just as i was typing that i could probably stencil the BF Goodrich out on the ultracote and just use that... maybe print a pattern off using the computer. Anyway, i'd still like some of the smaller and more intracate/colorful sponsor stickers. I looked through the stuff at the LHS but they just had stars/stripes warbird type stuff.

I have one with an OS 46fx, slimline pitts muffler, and running an APC 11x5 prop. Flys very well, not over powered but no dog either.
I much perfer the sound of a pitts muffler on a two sroke to the 4 stroke sound.
I have also built one that I haven't covered yet, got the other one used, good building kit but I second the advice about not using the rubber band method of tank placment.

What's wrong with the rubber band method of tank placement? So far it worked quite well for me.

The alternative is ____ , and the reason why it's so much better is ________ (fill in the gaps)?

Thanks.

Sašo

Nothing is per-say wrong with rubber banding it in my opinion. Myself..I just wanted the security of the ziptie. One tie, no fishing to get the band place. No dried up bands. It definately won't go anywhere until I snip the tie. Then to reinstall is a simple matter of working one tie under and up around the tank. I didn't have any ties long enough, so I do what I've done several times and just zip 2 together to make one longer one.
You don't have to change a thing in the plane, just one zip down and around the tank floor. Works from the port on the top front, right above/behind the firewall.
I guess I didn't like the idea of trying to reach the rear posts on the tank floor. Has anyone been able to do this? Reach the rear band-post.? With a wire fashioned correctly I'm sure it could be done, and I contemplated that.
One zip-tie fixed for good though. Also I'm running a 12oz. tank. The only diff in this though is length. Which makes no diff in mounting system. My 2cents.

PS I'm glad it worked for you Saso, and you haven't had any problems with bands breaking? I've got bands that seem to just dry up and go away. Maybe I need some new ones. For now though, zips seem to work everywhere an band does.

Zipties are great, no doubt about that. But my favourite is velcro, especially for mounting receivers and batteries. It kills the vibration, so you don't need any latex rubber around these components. Check the picture how neat that kind of installation comes out.

I got the rubber bands around the fuel tank in Extra with no problem at all (but it took a few minutes). I used it before and I like it, of course you can replace rubber with zipties.

Rubber is susceptible to UV light, which makes them "dry up and go away". Zipties have no problem with this, velcro either. But you need quite some velcro for for instance ST3250 in a quarter scale project - zipties are here my favourites too!



Sašo

BtW - you must check your fuel tank and fuel lines once in a while... and while doing this you simply change the rubbers and it's ok for one season...

Sašo

I'll have to get a pic of mine to you. I put the reciever in the cavity just behind the dashboard, then made a plate that covers it up and holds it in there. You see nothing in mine until you remove the cover(2screws). The only wiring seen(not hardly at all) is the power wire and antennae. They run along each side tucked in there own shrouds.
I notice you moved your servo tray, was this a balance issue. I couldn't move mine due to the reciever. I couldn't see putting the battery under the tank though, I tucked it back in the rear bulkhead behind the wing.
Balanced very well like this.
I put a small crutch in one of the sides that holds the switch/chg jack(Dubro).
Also I noticed you used EZ connectors(screw type) on your elev/rudd. Never any prob huh? I couldn't get away with that. I have to go with Zbends, and dubro control horns for servos.
What reciever is that? Is that one of those Futaba/Robbe units?
Nice plane though.

I had to put the servos back a bit - I have a .80 FS in the nose. Note the position of the Rx batt (5cell pack) also. I setup everything so, that the CG can be moved with batt only for 1/2" forward or backward.

Never had any problems with that EZ connectors. You just have to make it right - you have to do complete check-up of a model once in a while, all the screws must be tight and locked. That's about it. Why do I use such a setup? I don't use 2mm steel pushrods (GP original), but a 0.8mm springsteel in a 2mm teflon tube, guided thru 3mm plastic outer tube. It's light, playfree, no friction and durable. EZ connector on one side, CA and crimped threaded pushrod end with a clevis. Such setup is 60g lighter than the original version. Never had a failure in years (on GP Easy Sport .40 and GP Patriot .40, both .46 powered). Bigger airplanes have servos closer to surfaces and all the links are as direct as possible.

Rx is Futaba FP-118R (I think that this is the whole name of it, but it's from the top of my head). Receviers are Futaba, it's that "Robbe/Futaba" Tx that is different (formerly the FC-xx and now the FX-xx series). I have a FC-18 V3 plus, and as it looks like am going to FF9 this summer.

Sašo

Sounds like a real cool set-up Saso...pardon my asking but my geography stinks...where is Slovania? and what band do you operate on? Is that an FM reciever? I'm curious. I hope you don't mind me asking. The reciever kind of tipped me that things are a little different where you are.Don't know, ....can't be that different though..I mean different in how your frequency system is set up maybe?..That model reciever is not available here in the states. I imagine it's an 8 ch though.

I also have a bigger 4stroke and had to get the pack to the rear of the compartment. Those pushrod shrouds sure come in handy for tucking that battery away back there. With that setup balance comes out right on the money.
Thanks.

About Geography - Slovenia is a quiet little place (2 mio residents) right next to Italy and Austria. Landscape is great - it takes you 2hr drive from the sea to the alps. A lot of beautifull places to soar and fly. Attached pic has unfortunatelly nothing to do with GP Extra, but it gives you a picture of what I am talking about. Welcome - (and bring your Extra) !

We operate on 35 and 40MHz bands, you have to change the frequency module of your radio (official), but there is no problem flying here with your freq band either.

F-118 is 8ch Futaba receiver (exactly the same as the R128 in the states) - quite old, but extremely reliable. I have a few of them and never ever had a bad experience with it. It's proven, and simply rules.

Sašo

Well, i took my maiden flight yesterday... man what a crazy one. When i got to the field it was so windy that the plane was nearly ripped out of my hands by the wind while i was carrying it. I just had to fly though so i waited for it to calm down. After about 5 minutes it seemed to calm down quite a bit. The thing is, it seemed calm relative to how windy it had been before, but had it been this windy normally, i still would have thought it too much wind to fly.

In any case, i taxied out and began my takeoff roll. Man that saito .72 is one sweet runner by the way. The wind was coming in at about a 45 degree angle to the runway, shortly after the tail came up, but before i was ready to rotate and begin flying, the plane began rolling to the right while still on the ground. I was only at about half throttle at this point. I'm not sure if it was the right thing to do, but what i did was slam the throttle forward, throw it some left aileron, and up elevator. Suddenly the thing was pointing straight up and climbing like a rocket. I got it leveled out about 100 feet up. From there i thottled back to about 1/2 and continued to climb at a much more gentle rate... for about 2 seconds. Thats when the first big gust hit the plane and immediately threw it to knife edge on it's right side. The rest of the approximately 2 minute flight consisted of me frantically trying to keep the plane more or less right side up while the wind bucked it all over the place. On one pass the plane was travelling on a path parallel to my shoulders but was facing almost directly at me due to the wind. I was just trying to keep from crashing long enough to get another slight break in the wind so that i could try to land.

After about 3-4 terrifyingly out of control laps the wind took a very short break so i brought the plane down very fast and tried to make a practically zero approach landing (i wanted it safely on the ground before the wind picked up again, i didnt care if i hit the runway or not). The thing turned out to be a sweety and floated forever all the way down the length of the runway. I finally put it down on about the last 4 feet of runway and it obviously rolled into the grass. At which point the nylon LG bolts snapped (as i wanted them to) and the plane finally came to an undamaged stop. What a relief!

Needless to say, i decided that it really was too windy to fly for the rest of the day. It's lookin' nicer today though, i think i'll go give it another shot in an hour or 2.

One thing i noticed was that my ailerons seemed somewhat unresponsive. I think i got too much glue in the hinge gap and they weren't deflecting enough or moving very freely. I've cleaned up the gap and incresed the deflection. I may try sealing them with a small strip of covering also.

I sure hope my next flight will be a little less nerve wracking!

This almost became one of "that" crash stories...

Serious - my first flight was very uneventfull. With that ASP .80 FS and 10% nitro, 12% synthetic oil fuel it gets airborne at a few clicks less than half throttle. She needed no trim of whatsoever, but I had it nose-heavy on a first couple of flights.

Today I've made 4 15min flights, and it feels rock-solid. We get to know each other better and better. So far I have 24 flights on mine, and am still very satisified.

I move CG backwards each day we fly a bit. This helps, and the more I move CG back, the more I like it. It's a sweet flying plane, that's for sure.

About ailerons: on low-rate they are not very usefull (I have an electric slow-flyer to do such a lazy eights), high-rate is good, but not excellent. I have the throw as far as it goes (that's 13mm each way), and this feels just right (-35% expo).

To comment your story: personally I think it's better to get to the field ten times to just walk around or taxi the plane due to wind conditions and get the bird home in one piece, than to go to the field "just once, but more than enough". We build them to fly and enjoy, right?

Sašo

Thanks for the comments Sašo.

I did fly again today and things went much more smoothly. It was still breezy, but not too bad. It sure does have enough motor, i dont think i ever went over half throttle. It'll be a little while before i am as comfortable with this as i was with my big stik. I'm not sure if it was just the wind today or what, but the plane seemed kind of unstable. Even with my hands off the sticks, the plane would sometimes do small little jerking movements. Made me look like an even shakier pilot than i am, lol

It's hard to describe, but the plane just feels kind of strange, and is a little bit of a handful. Probably part of it is caused by me flying a little slower than is ideal. Tomorrow i'll probably follow the trimming procedure in the manual and see if i can't get the plane flying better. Maybe i'll try moving the CG ahead a little if it still doesnt feel right.

As far as the roll rate, it did improve a bit after i increased the throws, and more airspeed also helped. Although it's still not what i expected.

Like i think i mentioned before, this is my first four stroke powered plane, and i'm really tripping out on that part of it. I love the smooth running, throttle response, and best of all the sound. The saito is also a very beautiful engine, with the polished valve covers, pushrod tubes, and intake pipe. Also the curved cooling fins look nice. It has the same type of pleasing characteristics as a nice watch. I guess i just enjoy a well made machine.

Congratulations MiL! So glad your story had a happy ending too. Just take your time and get to know the plane..your doing very well with it. That strange feeling you have might be the fact of not having a total aerobatic plane before. Have you had a full blown aerobat, or is this your first? If you havent, that may very well be what your strangeness is. You might try just slowing it down for a bit. There's alot of power, and some....hehe..I'll try to say it so you can know....some stable instability. It's a happy medium is what it is. The plane will tumble all over the sky, ask me how I know. When slowed down decently though, it should respond well by simply obeying commands, without the strangeness. I think you experienced that upon landing. You might want to be careful on calm days, and keep a little power all the way to the runway for the first landings. It's easier to land into a decent breeze. Without the breeze I keep a click up on throttle until about a foot off ground. No prob there.
It is really pretty stable compared to some I've had, such as the Sukhoi SU26 I have, major handful there. The EXTRA is a breeze.
The thing will do it all though, just don't make it do it until your ready. You've made it....now it's a matter of fine tuning....the manual has some very good tips on trim/balance/set-up...use this and you will have a show stopper before you know it. It will make you look real good. Report back soon..let's here how your latest session went,,,,,, C-ya

I was wonder how a Tower .46 engine would work in a GP Extra 300S .40. When I compared the specs between the many recommended engines in the Tower catalog it looked like a competent substitution.

I think most .46 sized engines would work pretty well in this plane, however, i haven't heard too many good things about Tower engines. The only Tower engine i've ever seen personally seemed to have an air leak around the carb or something because it didn't run worth a hoot either.

If you already have the engine, and it works allright, then it'll probably work just fine on the Extra. If you don't already have it, and you're looking for something cheap get a Thunder Tiger or even a Magnum. Both are very inexpensive motors that are good performers, especially the TT.

If you take a little time with your Extra, it comes out real nice (see attached pic), this pic is of the GP's .40 size Extra with an O.S. .70 FS in it, Stans cowl and pants, fuse was built up to allow for cowl and canopy to blend in smoothly, plane weighs 5.75 lbs. (did I mention that it also has scale tubular frame cockpit detail.

I don't know Tower engines, but I know Magnum, TT and Supertigre. My choice would be TT .46 PRO, which was my first choice for my Extra. Fortunatelly, I got almost new ASP.80 FS - I don't regret this at all...

I have a TT.46 PRO on my GP Easy Sport, and it's a hell of a performer. I hauls that 2.6kgs through the air with authority. Verticals are excellent, but after 150m from full-throttle level flight it goes out of breath.

ST .51 would be another one - extremely light, powerfull, but a gas (glow?) guzzler.

If you are thinking about some serious aerobatics, four stroke is the choice. It's beautifull to see your Extra make a 200m diameter looping - slow it goes up, slow it goes down. And about that vertical snaps... When going home, you just can't stop grinning...

Sašo

Thanks all for your recommendations on the engine. This is the first kit that my son have attempted. It sounds somewhat daunting but the fact that the instructions appear to be complete we are hoping for a good result. We have watched an older gentlemen at Pegusus R/C Club in Hagerstown MD fly two of the Extra 300s and we were impressed. My son is about to solo on his trainer next week so we know that it will take some time before he is ready for this bird. I am someone what digitally impaired, but I love to build things. I will report back on the Tower .46 once he gets the plane up. We bought the motor on the cheap because my wife is watching the expenses mount with our new hobby. I hope I was not too cheap. I am not a flier but have been designated as maintenance crew and chief investor. Gosh this is an expensive hobby, but oh how addicting it seems to be. My son can't wait to get to the airfield over golf, soccer, swimming or any other sport. I like to go out just to watch the planes fly.

I dont know what makes me drool more bash-ace, your plane or your flying feild! That looks great, do you fly w/ that 3 blade?