buzzbomber

Dragging this thread back to life. I got most of my aforementioned products out of the way, so I decided to start on the QFII. So far, I've been spending a few minutes on it here and there, and I've got the basic fuselage box together with the bottom sheeted, and the boom support blocks sanded, but not glued in yet. Laser cutting is so nice!

Sky Sharkster

Hi Matt, glad to hear you've started on the kit.
I finally got mine flying, and can say it's well worth the building time. Sorry no photos yet, I was flying alone and wasn't able to take any flight shots.
First I made a couple of hand tosses by just holding the fuselage and launching it overhand. It flew well and I got the trims set. The rudder control was perfect but the elevator control seemed a little jumpy. I dialed in some expo and gave it a harder toss. The launch height wasn't great but it leveled right out and flew fine. It still seemed to gallop with elevator control, though. I re-checked the throws and C.G., both were fine.
Next I held it by the peg and gave it a hard toss, but without spinning my body first. It started out flat, then climbed up at a medium angle. Again it was easy to level it out without stalling and I did a couple of gliding circuits before hand-catching it. The elevator was so touchy I basically left it alone. The tosses got somewhat harder and the model showed no bad habits, it fact it glided very well.
On the last toss I got good launch height, but had no elevator response at all. From the top it took a shallow dive angle and all I could do was watch. Luckily we've had lots of rain here and the ground is soft.
It stuck in the mud like an arrow, but absolutely no damage! As it turns out the elevator servo must have been going bad, it wouldn't work at all. The rudder still works fine. They are both HS 55's I've had for a while.
So, I packed it up and brought the model home. I'll replace the servo and try again. From what I've seen, the model flys very well and glides beautifully. I managed to chip the leading edge of the bottom fin on some weed stubble, will run a bead of CA along the edge to strengthen it.
Ron

buzzbomber

Dredging this thread up because I finally finished building my QF2. There were a lot of headscratching moments along the way where my intuition told me to do things one way, the kit manual another, and the Paul Daniels guide yet another. I'm a bit annoyed because my tailfeathers picked up some warping after I glued the whole shebang together, but I'm sure it'll fly fine. Came in at 7.9 oz all up with ballast to balance on the spar. If the ground ever thaws, I'll give it a toss.

MS_in_NY

Thanks for bringing this thread back. I've got a QF II under the bench that I plan to build soon. I'll be reviewing this thread for sure.

Tomorrow looks decent...hint hint...under 5mph wind and mid forties.

......Mike

Sky Sharkster

Hi Matt,
Glad to hear you finished your glider, good luck with the flying!
Hello Mike,
I think you'll enjoy the build, it's a bit time-consuming but not hard.
I've flown my QF-II about 20 flights since replacing the elevator servo, and can say it's a very good intro DLG. Easy to trim, launches aren't difficult or scary, and the glide is flat and slow.
Although wintertime and snowy fields aren't ideal for thermals, the model has managed to find a few small bubbles of lift and I'm getting better at working the low level, weak lift. Can't wait for the hat-lifters of summer!
My throwing arm got a bit sore the first times out but now is used to the motion and the velocity is better. I still get the occasional Loopy, over-the-top launch, must remember to keep the nose level!
Ron

MS_in_NY

Hi Ron,

Thanks for the build thread and the great pics.

I've got a MM J3 almost finished, and a Magpie Sport is next. Still very new to this RC flyin thing and the Magpie is gonna be my "crash" course into 4 channel flying. The Magpie should be a pretty quick build then it's on to the QF II.

I've been through a couple big threads on the QF II and it does look a bit challenging, especially if you shoot for the lightest AUW possible.

If I do any posting about the build I'll do it here if that's OK with you. I don't really have the ambition to create a full blown build thread of my own. I did the same thing with my J3 build, I kinda tagged along on texasclouds J3 thread.

........Mike

Sky Sharkster

Hi Mike,
Sure, you're welcome to add anything related to the model, here. My threads tend to wander quite a bit anyway! Kinda' like my flying.
Ron

buzzbomber

So, I did the test glides yesterday, all went well. Today it's dead calm and in the upper 30's, so the glider came along to work again. I went to the ballfield across town on my lunch hour and tried my hand at discus launching. My first launch was a good one, the second one not so much, and a few good ones and some more not-so-good ones followed. I actually caught a light thermal on one launch and stayed up for a bit! I need to pull the covering and re-epoxy the launching peg though, it worked loose - contemplating a ring of 1/32" plywood reinforcement. Also, I need to work on my launch technique, as I wound up hooking it on most launches and frantically kicking in some right rudder to compensate. I'm hooked though. If I can sum up in one smilie, it would be:

PaperAirplane

Good job, Ron!

MS_in_NY

Well, I never did take any photos or do any posting during the build but that's mainly cuz the build was pretty straightforward. Don't know if that's because I'm getting better at it or the QFII is just an easy build.

One thing I recommend is use a #11 blade to nip the tabs on the ribs when removing them from the sheets. Especially ribs 5,6,7. The part of those ribs that passes through the spar is incredibly thin and delicate. You can snap the #7 ribs by breathing on them. As soon as I had them loose from the sheet I dripped some thin CA on those thin sections. I amazed myself by completing the wing assembly without breaking any of them.

I used MAS epoxy with slow hardner for all the fiberglass work. It's available from Chesapeake Light Craft. I highly recommend it. With the slow hardner you get a good hour plus working time, the stuff is very thin, wets out nicely, and cures clear as glass. It remains gooey for at least 3 hours and definitely needs a full 24 before sanding.

AUW came out at 232 grams (8.18 ozs) with 14 grams of lead needed in the nose. The bare tail parts were 12 grams after glassing. The covering on the wing is transparent red Solite. I have it balanced at the rear shear web line.

I added strips of carbon tow along the pod sides (a tip I remembered from another build thread somewhere) and I used a magnet to hold the hatch on. I drilled air flow holes top and bottom to cool the 1 amp BEC. I held the BEC between my fingers while swirling the rudd/ele stick and it definitely got hot.

Electronics are...Spektrum AR6110 RX, Blue Arrow 1 Amp linear BEC, 2 GWS Pico servos and a Rhino 2s 360 battery. It took some puzzling to fit everything in but I like how it came out. One antenna of the RX sticks out the side of the pod. I glued a piece of UNshrinked shrinkwrap into a hole as a guide tube for the antenna. The other antenna runs forward along the inside bottom corner under the foam spacer.

Maiden hand tosses went fine. I was terrified on my first discus launch attempt. I had visions of utter disaster but it was way easier than I imagined. I've probably thrown it 40 or 50 times so far. They aren't always pretty but none of the launches so far have failed.

I've had to re-glue the h-stab/boom connection once and I added a fold of clear tape to the bottom of the v-stab as a sort of tail skid. The v-stab immediately started showing evidence of my ineptness at hand catching the landing. I'd say I'm hand catching about 1 out of every 10 flights.

A new friend at the club I just joined was kind enough to video a few of my launches and put them on Youtube...

http://www.youtube.com/user/BikeRDS42

...there's five short vids. If anyone sees something horribly wrong with my throwing form please say so. I'm only getting 40 or 50 feet so far. When I try for more height I end up hooking to the left bad. Even when she goes up on her left side a quick blip of right rudder straightens her out.

Really enjoying this bird. Of all the models I've built so far this one is likely the one I will build again.

..........Mike

texasclouds

Mike, looks great and nice video. Your toss looks good. You need some buzzards to find the thermal for ya!

MS_in_NY

Thanks Mark. I think I'm gonna need some luck finding a thermal below 50 ft. Hopefully my launch height will improve with practice.

I've been lurking on your Hellcat build. That came out sweet. I'd say you're definitely a contender in the contest. I might be joining in that contest soon if I ever get the PLD Seether short kit I'm working on now finished.

.....Mike

texasclouds

I think if I did some airbrushing details and weathering, my odds may improve. Some of those guys are doing scratch builds...that outa give them a little leg up. I'm sure mine will be the only red one...

Sky Sharkster

Hi Mike,
You did a fine job on the build, looks great!
Good to hear you've got the model flying. It's really easy to toss and the trim is simple. Some flyers use a switch (like the flap switch) to put in "Launch" trim and turn it off to normal glide trim at the top of the climb.
Depends on your radio and set-up modes.
The low-level thermal flights will come once the weather warms up. It helps to watch birds, too. Last week I saw a hawk fly off a tree, maybe 50 feet up, straight into a small bubble of lift. He worked to up to a few hundred feet within about two minutes, then flew straight upwind, searching for dinner, no doubt.
Anyway, I noticed he turned tightly on the upwind part and opened the circle wider as he gained altitude. Tight at first, then a smooth open oval later. I'm going to try that next time I fly the QF II.
Good Luck!
Ron

MS_in_NY

Hi Ron thanks.

I was thinking of using the elevator half of the flap switch on the DX6i as a selectable trim control. Perhaps minimum sink and max glide settings. I'm not clear on what "launch trim" should be.

As it stands now I think my CG must be fairly close to neutral. It holds whatever pitch angle I put it in from just above stall to fast dive with no noticeable tendency to porpoise or tuck under. It launches straight (when I do it right), again with no tendencies to loop either up or down. It needed no elevator trim to get this. The elevator is dead neutral. Of course 50 feet altitude doesn't allow much of a dive test but I'm pretty happy with the way it handles.

I could definitely use advice on getting higher launches so if there's a trim setting bias that favors launching I'd love to hear about it.

Thanks again.....Mike

Sky Sharkster

Hi Mike,
The launch trim consists of two parts, the rudder and elevator. I've been putting them in separately, but I guess you could do them together if you're careful.
The rudder trim is one or (at most) two clicks of right turn for launch, to counter the spiral (diving) turn caused by the spinning launch. The harder I throw, the more it's needed. On a weak toss, it's not needed at all, and can cause a sharp right banking turn.
A small bit of down elevator will help the over-the-top or looping climb. Again, this is worse with a hard toss. The elevator trim is set for a couple of degrees of positive incidence for a good glide at slow speed, but this is too much "Up" at high launch speed. If the nose gets past 90 degrees during the climb, it will 1/2 loop or stall, costing a lot of altitude.
Ideally, it should just be nearing a true vertical attitude as it runs out of airspeed at the top, and you can push the nose over into a straight-ahead glide. Then you pop the "Glide" trim switch and look for lift.
Part of the equation is the exact position of the glider relative to the wind at the release point. I've found that my launches are better if I'm not quite dead into the wind, but slightly before that. It's just coming into the wind, if that makes any sense. It's hard to explain.
Last, you'll catch the model more often if you give up on lift-finding at about 15' altitude and just set up your landing to come around about 5-6' altitude straight into the wind, heading right towards yourself. Get it floating level and at the last second, remove your hand from the TX stick and catch it. I usually grab the wing, it's flying slowly and doesn't seem to hurt anything. I catch about 1/2 the landings this way.
Ron

MS_in_NY

Thanks for the tips Ron.

I've been blaming my left hook on my launch technique, or lack thereof, but perhaps I just need that click of right rudder to straighten out my launches.

It's gonna be way too windy for the next few days but I'll give those tips a try next time out.

.......Mike