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Jul 03, 2012, 01:34 PM
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sloperjoe's Avatar
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thanks Walt,
its an easy plane to build, sanding the wings and rounding corners are the time consumers and even then its not bad, 100 grit cuts this stuff fast, 200 and 400 smooths it out quick.

hey i12flyrc,
probably not...I just dont feel comfortable under handing...never have..did alot of hand launch glider flying and thats what I am used to. I posted that video that was like my second flight and I misjudged throttle power and angle, sense then I have had no problems getting it in the air.

Vic, sure I'll get one up, there is no thrust tube or elaborate ducting on this plane, the fan just mounts in the center rear of the lower box and blows straight out through the rear splitter, but that doesnt mean someone wanting to "hotrod" this design with better ducting/thrust tube and 5s lipos couldnt.

here are the butt pics

PS, you'll notice I have'nt planked out the small section behind the exit or just behind the tail mount, I'll do those after the the pushrods are in.

Joe
Last edited by sloperjoe; Jul 03, 2012 at 05:23 PM.
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Jul 03, 2012, 02:12 PM
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now I made the splitter out of regular 6mm depron because I wanted the stiffness, this part is one of the most critical parts on this design it adds an extreme amount of strength along with the verticle stab, it also locks in the tail incidence and makes the tail section rock solid so its not all noodley. before this part is added just the slightest side push on the tail will flex the tail boom, adding the verticle stab stiffens it some, but adding the stiffener/splitter hardens it solid. eyeball this part well while mounting, it must be very straight, if its in crooked it may induce side thrust. I draw centerline reference marks on the fuse parts to aide in alignment while building. hopefully mine is in straight
Jul 03, 2012, 10:40 PM
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just got back from the tall grass test glide site, the glides went very well, the CG on this one is different, need to put a ruler on it and get an accurate #. my guess is anyone who builds this plane should plan on test gliding for best balance. subtle differences in the tail incidence caused by cutting the parts even just a little off can change where it will like to fly.

my daughter videoed some of the test glides, after the best CG point was found I threw the Phantom several more times to confirm it was where I wanted it...I like it, and it appears I did glue the tail feathers on straight...lucked out again eh..

Joe

TESTGLIDES (1 min 8 sec)
Jul 04, 2012, 03:29 PM
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Waltjg's Avatar
Man Joe,,,,they looked all good to me!!! !! W
Jul 04, 2012, 04:23 PM
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Happy 4th O July Walt,
yeah they were all within an 1/8th inch of each other, it was also just a tad on the breezy side but not bad, I like to get a nice level glide set and no stall when speed bleeds off, just a nice soft floaty level touchdown. less fiddle'in with trims this way.

I have the servos and control surfaces all set up, and the fan unit is mounted, she is ready to fly But its the 4th and time for some Bar-B-Q'in and fireworks, not to mention its way too breezy today...must be 15mph breeze and by the way the trees are moving I would guess gusts of 18-20 going through intermittently. so the maiden will need to wait another day

in the mean time here are some install pics on the servo set up and motor install.


Joe
Last edited by sloperjoe; Jul 14, 2012 at 02:38 AM.
Jul 04, 2012, 04:51 PM
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Hi Joe, happy 4th of July to you and your family!! We had our cookout at the field today, lots of planes, lots of flying, lots of fun,, then took a break in the flying to grill out, eat and then back to fly some more!!!! A great day(especially since all my stuff came back home in tact!). You'll have to keep us updated on the maiden flight, of course with pics and vids.. I got some vids today, but need to edit them as the files are BIG... So well see... Have a great day!!! W.

PS.... Don't get glue on that table or you'll be a dead man!!!!!!
Jul 04, 2012, 05:42 PM
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by Walt,
"PS.... Don't get glue on that table or you'll be a dead man!!!!!! "

heeeeheeeeee....too late!, see what ya can get away with when the wife sleeps in!?
muah ha haaaaa..

you have a good rest of the day too!
Joe
Jul 04, 2012, 05:59 PM
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Very nice Joe. Do you have a paypal account? I gotta do this one at 140 - 150% full house. I like it! Nice to have the girls involved too. I did not see any exhaust duct....?

Kim
Jul 05, 2012, 01:31 AM
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Hey Joe,

Great job on the build! It looks great and flies just like a parkflyer should. Did I read this thread right? People are flying using the Detrum 70mm fan/esc combo all day long on 5S with no problems? 56amp draw on a 5S pack won't fry the 60amp rated ESC but will the motors hold up for long? The reason I ask is that I have a pair of these 70mm detrums going in my Mig-29. At 4S they're giving me 84oz of static thrust with a combined amp draw of 68amps, but I would be jazzed if I could fly it on 5S

Vic
Jul 05, 2012, 01:36 AM
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thank you very much Kim,

I do have a paypal account sloperjoe@netzero.com
and no there is no exhaust ducting on this design, just did this one as a simple park jet to fit the 70mm Detrum combo, a thrust tube and better intake ducting would probably improve the performance but also add weight... so it was a trade off, I wanted to keep the AUW as low as possible for flying at the schoolyard down the road.

Joe
Jul 05, 2012, 04:51 AM
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hey Vic,
I personally have not gone 5s on a 70mm Detrum unit (dont really need that kind of umph for where I fly), Lt599 has and several others have that I've read about while researching for the thrust ratings on these units before buying one...it appears the motors and ESC's hold up just fine. I didnt see anything where someone stated they fried one on 5s...I can say if 5s doesn't fry em, it'll sure blast the air out.

Joe
Jul 05, 2012, 07:10 AM
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Well, I just don't know, I'd do a lot of testing before I stuck it in a plane and tried 5s... My luck with going a cell larger on EDF setups have ended in burnt up motors, twice!(they weren't the Detrum units though) So like I said, I'd do a lot of testing with bench running.. The ones I've tried this on have lasted 2 or 3 flights and then scorch! And I do use a lot of throttle management on my planes... Vic, keep us posted if you try this... W
Jul 05, 2012, 10:32 AM
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AWsome!
Jul 05, 2012, 03:55 PM
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sloperjoe's Avatar
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just want to clarify my earlier statement...I have NOT gone 5s with these units... I cannot say definitively that its ok to do so...I just havent found anything that is in writing or posted anywhere that running 5s is detrimental to the motor...however I would have to go with Walt on this one, do some testing...but if you have the urge to run one on 5s in a plane let us know how it holds up...by that I mean at the very least ten runs or so...just two or three flights does'nt mean its "good to go"...at least ten with no signs of excessive heat in the motor or ESC...if you already have a bunch of flights on a 5s 70mm Detrum unit post here what you know.... I am curious to know myself.
Jul 05, 2012, 07:03 PM
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well.....just got back from a nice TALL grassy field and the attempt at maiden...all I can say is sometimes the best laid plans just go kaput during the real thing...it would appear my glide testing method was somehow flawed....the CG appears to be exactly where the plans show they are marked, I made 6 attempts moving the battery forward gradually with tail heavy results...luckily I had nice tall cushy grass to keep the Phantom from any damage. attempt #6 was almost but needed to have the battery shifted forward a little more, but it was velcroed with a more rearward position so I didnt attempt any further flight, that and the cam batts went gunny sack...so on returning home I stuck a pencil on the original Phantoms balance point and moving the batts forward came to the spot I concluded they needed to be in relation to attempt #6 batt position... so it would seem I actually did mark the correct CG on the plans after all, anyhow it is still early and I will re-velcro and take it back over to the field in a little while and see if I cant get this baby flying. so stay tuned..


oh by the way all the video was useless to watch, had the angle wrong on my forehead....you could hear it...just couldnt see anything... I will try to get my daughter to go with me later to be sure it gets recorded. good or bad...


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