|Oct 06, 2001, 12:55 AM|
San Antonio, TX, USA
Joined Jan 2001
JKA Big-T Bird (T96) is here!
Found UPS had delivered my JK Aerotech T-96 combo today!
Construction has definitely begun.
This is the JKA Big T with 2-48" wing panels instead of the usual 36" wing panels. Will need to splice some 3/16" square spruce spar materials (long scarf joints).
How did I get them 4' instead of 3'?
I begged Jim and Ken a lot.
I also bought extra batteries (10x1400 somethings, sub-C?) and extra props MAS 10x7E.
Put the supplied APP connectors on the batteries (what I use) and am slow charging the first of them.
And have vinyl adhesive lettering, etc on order from a club memeber who has business making things like this.
Going to cut ailerons in the wing like this:
Coming in 1" from wing tip, draw a line 1 1/2" from TE towards LE, coming in 25" from wing tip, draw a line 1 1/2" from TE towards LE, connect the ends of the lines for a 24" long x 1/1/2" aileron. Cut out out, sand lightly and bevel LE of aileron at 45 degress. Apply 2-1/32" ply squares to opposite sides of foam aileron in the center for the 1/2A control horn mount. 3M77 and tape aileron. Place 1/8" space between wing and aileron LE with aileron at 45 degrees down - apply clear tape as hinge the length od the aileron. Flip aileron up on top of the wing and apply clear tape to lower side of aileron, wrapping under the wing. Press the clear tape (sticky sides) together along lenght of aileron and fold down into place.
Mount HS81MG servo on side, embedded in bottom of wing, forward of the control horn location. and apply linkage. I will need to solder on long servos extensions and make a Y at the middle bottom of the wing.
Does this sound right?
I have never built a aileron ship before (except wings like Zagis, Flitter 400 and Wally Wonder Wing).
This is also my first big bird, first tail dragger.
It MUST be flying ok BEFORE the first weekend in Nov.
We have our 12th (or 13th?) annunal Elf Louise (charity) Big Bird Flyin than.
Last event father and son cooked but did not fly.
This time we are going to cook on the ground and in the air!
I having TOO much fun here!
|Oct 06, 2001, 10:15 AM|
You'd better register that thing with the FAA!
I hope that you're planning on using balsa ailerons and not the foam that you've cut out.
What power are you planning using? The 10x1400 somethings are AE's I believe (I think that's what JKA sells). They're not sub-C's though.
Make sure you post some pics...
|Oct 11, 2001, 04:07 PM|
San Diego, CA
Joined Sep 2001
Regarding aileron hinges....
You mentioned hinging them with tape and I know I've seen a variety of different ways to accomplish this. A single strip of tape along the entire length of the aileron obviously prevents air from sneaking through...
Can someone (hoppy? Sal? Silver? ChrisD?) who has built T-52 and attached ailerons comment on their methods?
Some other methods I've been reading about:
And there is special tape that is stretchy.
And glue-it has pictures of a "middle" hinge (basically a 45 on both sides of the aileron)
|Oct 11, 2001, 08:43 PM|
I gotta agree with Sal here. For something that big, I'd use hinges ala scooter's ailerons for the Big Bird. Phew!!! I'll bet the
FAA will track this thing on radar!!! What is proposed power plant for this monstrosity? Maybe something geared. There looks to be alot of drag for a wing this big. I know my T-52 flew okay on a speed 400 direct. However, I threw on a wattage 480 coupled with a grish 6x4 and my T-52 tonite flew the best it ever has. Good speed and climbing ability. Plus, it now has extra weight with the 480 and the ic 380 esc. Haven't weighed it but its gotta be over 26 oz. Want to try a magnetic mayhem with it next with a gearbox. Or, just save the mayhem for my home built foamie.
|Oct 11, 2001, 10:51 PM|
San Antonio, TX, USA
Joined Jan 2001
My T-52 is 22 1/2oz without battery and flies with a 450 Turbo and Grish 6x4.
Batteries are 8x 500ar, 600ae, 1400?, 1700au, 1600 NiMh
Interesting methods - I enjoyed reading them. Thanks.
I am proceeding with 2" x 24" ailerons, set 1" in from the tip, cut out with the aileron LE beveled 45 degrees so it can pivot down without binding.
I am using larger control horns, not the 1/2A orginally intended.
Discovered I need to make some long screws to go thru the aileron to hold the horn on. The aileron is thicker than I expected at its LE (about 1/2").
The drive system is 10x1400 (Panasonic P-140SCR, 42mmx23mm, 1.69oz, 6mOhm) using APP, a Kontronik SUN 3000 ESC (30A cont, 45A 15 sec, current limited, 6-16V, 2A BEC for 4 servos even with 12 cells), motor is GR 500 BB Race 8.4V, MAS 3.5:1 GB and MAS 10x7. There is a set of APP connectors between the motor and ESC. THe motor and ESC arrived today.
Ken at JK did promise to get a motor to me in time to build and fly this beast before 3/4 Nov - Elf Louise (charity) Big Bird Flyin the San Antonio Prop Busters are holding for the 12th/13th?? time.
The motor may not be the regular one since they have been having supply problems since the attack and over-demand for their product.
MY LHS is having a hard time getting routine things for me do.
I bought 3 packs with the kit. Using my Dymond Smart Charger the first pack came up to 1580mAh on first slow cycle. I cycled it twice more with same result. Automatic cycle was 1540mAh.
The second pack started out at 1130mAh! Six cycles later it is at 1590mAh slow. It just beeped indicating the end of the Smart Charge auto discharge/charge cycle (nicd) - charged 1538mAh. I am happy with that.
The third battery is now starting its first slow cycle.
Currently I am soldering the extension wires onto the servos. I am planning a flaperon setup using 4 HS81MG servos (R/E/2xA), JR R600 RX and JR 421 TX. I mocked up the servo/rx setup then played with the radio programming until it all worked as expected for flaperons. The 421 is a 4 chann+1 gear (up/down switch) chan with no mixing, flaperon or delta mixing and 2 model memory.
I plan to set the servos in the wing then spray and tape the wing panels. I dislike cutting my tape job to put in wires so I do that first and mask the servos while spraying 3M77.
Building has been slow due the that little thing called WORK (plus a yard, wife, 2 kids & their homework, etc). This week end should be good for building as weather looks bad.
|Oct 12, 2001, 01:56 AM|
I haven't used it yet, but I have seen a new filament tape called "Ultra" tape. It has fibers that look like "H"s instead of just long fibers. The fibers have shear strength in both longitudinal and cross-tape directions.
This tape should be strong enough to be used as hinge tape along the length of your ailerons. Easy way to check would be to tape across the joint of two 1x2 pieces of moulding, place them over a dowel, and press down on both sides. Regular filament tape will separate at the joint, but I have high hopes for this new filament tape.
Hope this helps. Let us know what you finally decide on.
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