MJD

My Feedback: (1)

I hear that one. If you build a couple of .010/.020 models and paint yourself into an equipment corner once or twice - you'll never feel like you're working in cramped quarters again. As in "why did I ever think I could get my fingers in there", or "oh no, the receiver... where the frig is that gonna go?", or "so that's what 1/32" clearance really looks like..".

Small fuel tanks are a continual source of angst. I love Fuji film cans but you gotta sweat it out at the bench for an hour or two to learn your favorite method for penetrations/fittings. A mail order of plastic barb fittings from McMaster-Carr never hurt either. The cans are about 20cc so they don't run forever, but 4-5 minutes ain't bad. The cap is 1-5/16" OD which can be tight depending how skinny your fuse is. The weight of commercial 2oz tanks makes me shudder, I prefer the Hayes 2oz. They have a 1oz header tank too.

2oz


1oz

Tee Bee

Yep, agree. I've built a few .010/.020 birds and it's definitely less stressful to fit all the gear in larger models. I generally use 1oz tanks in my .049 birds but I'm trying to shoehorn a 2oz tank in there to keep the flight times up to 7-9mins with the .09. This was designed as a .15-sized plane so the tank isn't normally an issue to fit. With a .15 engine/muffler, the previous builders mounted their batts/servos behind the wing saddle for balance. Mine would be tailheavy if I did that. I'm trying to cram everything up as far forward as possible to minimize any additional ballast weight needed. I screwed up and used some CA kicker nearby that melted the throttle pushrod sleeve when it reacted. I had already sealed the compartment with resin, so I had to chisel it all apart. I walked away before I smashed the plane over my leg. I went outside to cool my head by flying my UMX Stryker which I promptly smashed to pieces by crashing it in my front yard. Some days...

MJD

My Feedback: (1)

LOL - some days the remedy hurts more than the ailment.

I make my own kicker actually, used to make it in the chem lab at a previous job where we used CA daily.. it is so-o-o rudimentary. I have a 250ml bottle of the catalyst which will keep me going for another few years. I make spritzers of foam/plastic safe using 2% in methanol or IPA, or regular using 2% in lacquer thinners or MEK. This helps avoid the problem of melting the material I'm working on. Years ago I used Freon 113 for the carrier, but that is kinda frowned upon these days, something to do with destroying the planet or some silly thing like that. Of course it works best of all, so it makes perfect sense that there is a major problem with its use.

Oh yeah, forgot this was an .09 deal, thinking 1/2a. I like the Hayes 2oz.

Tee Bee

After over 3.5 months of tinkering, I did the final assembly on the Shark XV last night. Though I tried to keep most of the heavier items up front, I ended up adding about .5oz of lead behind the firewall to get her balanced toward the front of the spar. All the others I've seen online had heavier .15 engines with their radio guts mounted behind the wing for balance. I still need to seal the fuel tank hatch to eliminate fuel/oil creep before engine testing begins. Here's the particulars:

Engine: Cox TD .09 with throttle sleeve. Big thanks to Steve "Little Rock" Staples!
Hayes engine mount modded a bit
Spektrum AR500 receiver donated from an old park flyer
Dymond 60 servos on the tail surfaces
Dymond 47 servos on throttle and each aileron
720mah NiMH flat pack. It's the largest I could squeeze under the tank up front and I needed more ballast.
Sullivan 2oz Flex Tank. I fitted 3 tanks before arriving at this one. Should allow nice flight times.
Sullivan pushrods. I still need to stiffen them a bit before flight. No biggie.
Ultracote Flourescent Blue and Safety Yellow covering with Monokote graphics
Wingspan: 40"
Wing surface area: 246 sq. in.
Weight: 23.4oz

Pond Skipper

Nice and clean great job.
The patterns under the wing should help when your rolling around.
What size cox prop is that and nitro % do you plan to use? At 246 sq. in.
should land with ease keep the underside in good shape at slow landing
speeds. Post a vid if you can will be a good one to watch!

Tee Bee

That's a 7x3.5 Cox prop in the pics. When they got hard to scare up some years back, I started buying them aggressively every time I found them on the auction site. Probably have a dozen of them including a few stiff grey ones. Also have some various 7x3, 7x4, and a few others you suggested earlier to play with. Planning to use the standard fuel blend I've been running in all my other Cox engines for years, Sig Champion 25% nitro that comes with a 20% oil mix that is equal parts synthetic and castor. I buy it in quart bottles and add another 1.5oz of Benol castor oil. It's been a while since I did the math but I think the extra oil brings the nitro down to around 23.5%. I like the added insurance of the extra castor and this combo has kept my other Cox engines happy for many hrs of flying fun. Admittedly, the only .09 I've run extensively was a Medallion which is still in good condition today. I'm only assuming the TD .09 will like the same fuel. I try to keep things relatively simple with my modeling when I can. I grab the doctored Sig fuel anytime I'm gonna fly Cox engines and take the Power Master 15% with castor/synthetic blend to the field for all my other 2-stroke and 4-stroke engines.

As for video, I certainly will try to capture some footage when the planets line up. If nothing else, my grown son travels to SMALL with me and usually shoots a lot of footage there for us to watch later.

Tee Bee

Pond Skipper, it's funny that you mentioned how slow she should land. I recently purchased an E-Flite Rare Bear that's pretty fast and hot landing. I've got 5 or 6 flights on it now. My heart has never beat so fast before while flying a foam airplane! This Shark ought to be downright relaxing compared to that.

Pond Skipper

20% oil blend is what I use with 30 to 35% nitro in the TX heat the extra nitro helps keep things cool in the summer.
I custom order my blend selection from FitzFuels.com aka Glowplugboy. 18% Klotz Benol and 2% klotz techniplate synthetic.
He is out of Houston cost for shipping is not bad. http://fitzfuels.com/index.php?id_ca...oller=category

Yes landing with under size wings can be tricky the DART at 106 sq. in. can literally fall out of the sky down wind.
It stalls out and tips the left wing at about 16 mph and will not recover in time. I have had to learn to keep it moving
and get it into the wind as soon as possible for landing when it dead sticks. It has fallen hard a few times requiring repairs.
I have had everything looking good in a glide then wham at even 5ft. off the deck it will tip stall if allowed to crawl in at
its threshold.

MJD

My Feedback: (1)

Due to local availability, my favorite two fuel options are SIG Champion in quarts + oil if wanted/needed, or O'Donnell car fuel with 8% oil and castor added to taste. I shoot for 22-23% total oil, but I will run the SIG straight on .049's without too much worry.

Tee Bee

Maidened the Shark XV this morning. I never bothered to test run the TD .09 that Little Rock sent me until I got to the flying field. I guess all that good clean living paid off, because it fired right up without much fuss and I had it tuned and the throttle programmed in short order. Many thanks, Steve! Sorry, Pond Skipper, but I never bothered to get any tach readings or such. Just adjusted it til it ran decent with the 7x3.5 rubber ducky prop. I launched the plane myself at full power and was pleasantly surprised, along with my fellow club flyers, to watch it climb out gently on it's own with no stick inputs! I remember rainedave's flight report saying his performed the same the first time out. I don't recall adjusting any trims. It just flew straight with authority wherever I pointed it. In it's lighter form and with no gear, the plane is a great match for the Cox .09. It grooved around the pattern very precisely and quickly, turned on a dime, and bobbled and hunted very little even though the winds were gusty 10-12mph. Rolls, loops, Cubans, inverted flight, etc. were great. Knife edge attempts didn't work out with the available rudder throw and power. Maybe a different prop could get it to hold altitude, maybe not. Who cares? I'm not much of a knife edge guy anyway. With 2oz of fuel, I got around 7-8 minutes of run time(In all the excitement, I forgot to start my timer on both flights.) On the 2nd flight, I played with the throttle a bit. As expected of an exhaust sleeve, it's not linear in response but it was cool to pull the power back to near idle and cruise by slowly before powering up into a reverse 1/2 Cuban turnaround. I had forgotten how great the mighty Cox .09 sounds when it zooms by. Woohoo! Dead stick glides to landing were a non-event, comparable to many of the smaller 1/2A planes I've flown, though I was careful not to get greedy with too much elevator before touchdown. She is a great machine that matches the kind of flying I most like to do. If these came in RTF boxes, I'd buy a couple more spares to keep or modify. I hope that rainedave will see this post and know that his great flying design lives on!

I also flew the Scalpel with it's throttled Cox TD .049 and LaStick w/TD .020 this morning. The electric planes stayed at home. I'm tired and my clothes smell of glow fuel exhaust. I'd have to say it was a good day.

Looking forward to flying this model at SMALL 2017 in June!

gmwahl

Congratulations! Great flight report and great looking plane. It looks to be a perfect match for the .09 too. Does it seem to fly blazing fast or is it more of a sport flier?

Mike

Tee Bee

I'd say it's "sport flyer fast" with plenty of authority for climbs and big loops from level flight but easy enough to manage at constant wide open throttle. Vertical is not unlimited but adequate for a nice turnaround maneuver. Seems to fly much like a Kaos or Ultra Sport. I've been flying a lot of electric stuff lately so I really enjoyed the contrast and character added by the snarly sounding TD. 09.

H5606

Agreed!

Regarding the LaStick in the last picture - is that the same as an Ace "The Littlest Stick"? Looks like it has elevator too; bet it moves right along with the TD .020!

Pond Skipper

Congrats Tee Bee, great flight report good to read it was a fuss free day of fun IC flying!!
The sound of small nitro snarling engine zipping along is always a big treat even more so
when you have throttle on tap to mix it up!

Tee Bee

Thanks! I'm very happy with the Shark.

Yep. The LaStick is basically a scratchbuilt Littlest Stick. I think Fred Reese drew it up years ago. I found the plans online free and built it 10yrs ago with 2 channel rudder/elevator. It flew the first few years with a TD .010 and was then upgraded with the TD .020. It boogies real nicely and does nice nice axial rudder rolls. Search youtube for LaStick and Tee Bee(my username) for some vids of it in action.

Pond Skipper

Any vid on this one Troy?

Tee Bee

No vids yet. Hopefully, my son will shoot some footage of it at SMALL next month. The plane has 5 or 6 flights on it now, all with the Cox 7x3.5 prop. I've been wanting to experiment a bit with some others but haven't gotten around to it. I'm curious to see how she does with the MA 5.5x4.5 and APC 7x4. A little more vertical would be nice to make those big loops and Cubans. Either way, she's a fun model and I look forward to getting some video footage of her in motion.

Pond Skipper

For reference Maiden flight vid:
Static MA 5.5x4.5 / 17.3k / 12.34oz / 74mph prior to launch.
Unloaded best peak pass at 24,467 good and rich.
2nd launch / 1st flight attempt had too much down trim on the
first launch and slid it in breaking the first test prop. Did not have
enough elevator throw to keep it clear of the ground so it only flew maybe
thirty five feet sliding along on the wet grass at a good speed.

TD .09 still needing some break in time. Run duration not so
good due to being so rich / 2oz tank. Was sprinkling rain this
cooled down the engine making it more rich as it flew. I was
hell bent for a test flight to see what the DART design could
do with 106 sq. in wing.




Noteworthy as it has performed well with the Norvel .074
APC 6x4 should make good thrust with some pep.

LittleRock

Really? 74mph before you even launch the plane?

Pond Skipper

Yes very much so:

"Static MA 5.5x4.5 / 17.3k / 12.34oz / 74mph prior to launch"

Knowing the static pitch speed results then taking the unloaded pitch speed gives you a percentage
marker to work with when selecting speed props for this given plane / engine platform.

If I was to modify this MA prop to phase it to the next level of speed would be 5x4.5N

Instead I found a lower weight carbon blend later after a engine swap and tested to the following results:
Posted vid: DART -Fuji .05 / Profi Tuned Pipe / HQ 5x4.5N
Static in the hand 20,429 rpm / 87 mph pitch speed
Best pass at 7:24 mins 26,082 rpm / 111.14 mph

The prop would do fine in stock form with the TD .09
N means I back cut the blade to tapper more narrow.

The mighty TD .09 topped out with these posted vid results:
DART -TD .09 / APC 5.25 x 6.25E / 21.96K rpm 144 mph best pass (safe rpm range for a non bearing TD .09)
DART- Fuji .05 / HQ 4x4.5 / 36.75K rpm 148 mph (with bearings)

lamp amuser

I know a guy who can run 74 mph with a toy plane in his hand, so... yeas, 74 mph before launching is a realistic number.

aspeed

Lamp Amuser LOL

LittleRock

So the plane can fly 74 mph without moving forward in the air?
I'm getting old and don't understand how that can be.
Would a radar gun aimed at it register 74mph.
Oh yeah, what is a Lamp Amuser?

aspeed

Any slower, and it would go backwards...

lamp amuser

I think that It's similar to a stationary bike.