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Old Aug 12, 2004, 09:09 PM
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Houston, TX
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Got 4 more flights in this afternoon on my 16.5 Windbuster with the new Hot motor. Throwing a 4x4 prop on 2s Apogee 830 gave me flights of 9m 49s and 6m on a half charged pack. On 2s Irate 850s, flights of 8m 37s and 8m 42s. That was with aggressive flying and a conservative 6v soft-cutoff. Flies great on these cells but there is a significant drop in power after about 30 sec. Too much fun.
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Old Aug 13, 2004, 03:08 AM
Master of the Wind
AIR MOVER's Avatar
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Those are reasonable run times with the hot motor..I feel there is another min or so you can shave off for more speed.. I dont feel the batts would be happy if you pushed it at the 6min mark.. but anything around 7mins should be safe...when your ready I have a special double wind that will nuke that pack at that rate with a HD4040... can help on the mags there as good as it gets.. but can do a special 2strand wind that will give you max stator fill to gain alittle more efficent motor allowing for more rpm.
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Old Aug 13, 2004, 04:11 AM
Renegade Fun Forever!!
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Fontana, California, United States
Joined Jul 2004
27,661 Posts
Watch out boys,
I've got somethin' for you on Saturday morning. Right Airmover? We been working on a special wing, tail feathers and leading edge. also special prop. Get ready hybris, theres a new WinBuster in town!! Still on 2 cells, but we think we got somethin' for ya! Birds all over southern Ca. are headin' north. Way too much FUN!!!!!!
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Old Aug 13, 2004, 04:25 PM
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Bob has a new beta test motor and a hot motor .. the wing and tail feathers are the same type .. and the carbon boom is a tad more robust.. the new motor is a 8mag very hot .. requires 1320's with the 4040 ideal is 3.740 to loosen the grip on the batts...should be able to hit 100 with this one.... its not made to run static.. its set for unloaded running .. and should be luanched 60% throttle to help milk the batts on luanch...pitch speed is over 100mph and unloaded amps are set at 8.5-9amps...the 10amp controler limits max speed.
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Old Aug 13, 2004, 04:57 PM
Renegade Fun Forever!!
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Fontana, California, United States
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I thought we were gonna keep that all secret!?? Ha-Ha Oh well the cats out now! You don't think that the "Hot" TP 730's can handle it? They are 10c-12c rated. I did modify a couple of 4040's.
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Old Aug 13, 2004, 05:01 PM
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Houston, TX
Joined May 2003
749 Posts
My 10.5C 830 Apogees did not even get warm on the previous hot motor and now they are about 40-45 degC. Apogee 1050s would be perfect.
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Old Aug 13, 2004, 07:05 PM
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The specs are but the bottom line is 8mag two strands of 24g... and of course you have the Hot motor..that Hybris has... for the 730s ..no telling how well the beta motor will do.. you will have the best shot for max speed with a 10amp esc with that one... I know the fets are rated for 15amps from the suppler.. so running at 10amps shouldnt be a problem on a clean plane...less surges.
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Old Aug 13, 2004, 07:15 PM
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Houston, TX
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You may want to wind for higher voltage. Going to 3 cell will reduce amp requirements with the same power. But then you could argue that adding a cell is heavier than going to a Phoenix 25.
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Old Aug 13, 2004, 07:38 PM
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yes its a tit for tat ordeal..and a price increase .. along with the dangers of 3s charging... and use... trying to keep the over all cost low.. if 10amp esc's and 2cells is enough to go 90 then really the goal is met...adding weight breaks planes faster....stresses the airframe ..and requires stouter gear...its tempting to give in to 3s as it helps lower amps.. gives more rpm.. the new 730s are a perfect match... nice an light.. as thick as 2cell 1320's ..Hybris if your willing to test a 3s wound motor let me know... if given motor gives out 24k at 8amps with 2s.. a 3s at 8amps should give you 26k plus on the same prop if the right wind is used.
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Old Aug 13, 2004, 07:59 PM
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3s charging dangers? Can't think of any. Any more than one cell can cause the imbalance issue.

Now for some math. 2s is approx 7v under load. 7v x 8A is 56 Watts. 3s is approx. 10.5v. 10.5v x 8A = 84Watts. That's 1.5x more power. So by theory, 22K would be 33K on three cells.

I have some 3s Apogee 830s and Irate 850s just waiting for a challenge. A fan project would also be fun (hint, hint)
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Old Aug 14, 2004, 04:07 AM
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1cell wont cuase any issues but 2.. and then 3.. and so on add more and more risk.. I have had one two cell pack puff on me thus far.. scary stuff as your not sure if your up for the big boom burn, flame bit if it does happen... The most you could hope for is a 3.7X4 spinning 28k.. if the effiency of the motor is at least 65% your going tobe at the max amps unloaded with a 10amp esc..around 9.6amps. The input watts to hit 33k would be over 140w...You have to bare in mind my motors are wound for max output..of what the motor can handle... no matter how many volts I use.. it can only swing so much prop...at a given rpm without overheating... cant trash the mags.. even if the esc and batts can handle the load...nor the insulation on the wire.. we can oversaturate the iron.. thats about it.The lil roms cant really handle the heat output of 84w.. I have ran them up in the 65w range with reasonble losses in heat...considering we are pushing the motors a Hot wound is already in the upper limits....I can for sure get 2k plus ... how I do it is allowing the motor to pull up to around 8amps unloaded..wire the motor to draw the amps without the heat...letting the esc and batts handle there share of the losses...to make it clear... if I had 8t of 32g vs 8t of 22g the 32g would sissle the motor ..when it comes to speed you have to limit the heat on the motor.. if I could burn 84w at no iron/copper losses life would be good but at around 65w the iron losses copper losses(wire size I can use) are near max... the only choice is to add more iron.. more wire more weight for more amps ...the ball keeps rolling...and im trying to keep it to single stator light motors.. 10a esc and best and lightest batts able to work in this range...I will have to snag a 3cell pack for testing and see whats possible. I will also do some testing with very high temp cobolt mags as neos are puppies compared to the heat capicity of cobolt mags .. there able to handle 400deg plus... allowing me to nuke the iron providing im using 22g or better...
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Old Aug 16, 2004, 12:28 AM
Why not Delta?
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Sacramento, CA
Joined Jun 2003
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Finally I had a couple flights on my new WindBuster today - still on the training wing. I run the first flight with 2 cels 700. Plane flew straight from the ground - no problem at all. No siginficant trimms - just one click here and there. What I noticed however, it needed a down thrust because it climbed like crazy on full throttle.

Anayway plane flew fine, very easy. I did even some hands-off flying at half throttle. But it was not as fast as I thought. Hah, what the heck - it's trainer wing.

I run out of the battery so I added down thrust and I run it on 2 cells 340 - same fun, just twice shorter. Still climbes a little.

Next I found the problem with thrust line - The wing is supported at the LE (by the plywood black) and at the center by servo, but at the TE it's just hanhing in the air. So rubber bands pushed the back of the wing down making it undercumber shape - high lift wing. I need to put a balsa block to suppert TE (like I saw seomewhere here on this thread).

Next I tried to run it on 2 cells 1900. Unfortunatelly motor shifted right (I need to come with the more rigit mount) and plane went left on the asphalt breaking the prop - jeez, my only 4.5in custom cut prop.

Then I found 4 inch prop in my box. What the heck - I can run 3 cells and smaller prop still with the current below 10A. So I put 3 cells 340 and 4 inch prop. And now - drum roll.....

This is a FAST plane. It's so slick, so it doesn't need such big prop disk. It flies excelent on 4 inch prop (i think it's 3.5 inch pich) spinning it around 30k rpm. So I found my setup: 4 inch prop, 3 cells. Next time I will try 3s700 for longer flights.

This time I'm seting up the racing wing - it should be faster.

So things to do:

1. Make a support for the wing so it stays flat even when pressed by rubber bands
2. Fix the motor mount so it stays in place - rubber band now allow it to move it around a little
3. Setup new wing - racing wing.
4. Replace fat foam wheels with the thin profile plastic ones - less drag, more speed.

Conclusion - just one: The plane is a winner, it will stay with me for some time

RysiuM
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Old Aug 17, 2004, 04:41 AM
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Ty Rysium!!! .. I leave the trailing edge alone .. its set to hover over the boom.. when you crash the chances go up for the wing.. also as the aileron servo kicks left right or back there is full clearance during nasty little wing tumbles in the grass.. Im looking forward to see what motor you like best for all out speed.. I try to wind for reasonble flight time and speed..also let me know if you incounter flutter past 80mph.. I use sq trailing edges as they help to stop flutter... this trick has been known for awhile and I found it helpfull.. when your ready for max speeds. I have a special 13.5in span wing.. just for the job.. it takes low rates to fly.. small half inch throws, ailerons and elevator.
for wheels I like the small black plastic micro tail wheels.. for me the wheels are used for looks and to have something for when its setting up on a shelf.. and such... in a pinch you can still land them on the wheels even in the grass... also you can use a small shirt button.. and drill a hole in the center.. I use a few raps of magnet wire around the piano wire to secure the wheel from slipping off... ..
the smaller wing will stand out and get you some rocket vertical... with the right motor.. if you can get a 4040 to turn up past 23k plus your vertical line should be outstanding...my batts of choice are the hot gen II TP860's for my two cell motors...If your willing try a 24g 12t Y 6pole 6mag 5X5X2mm N50 with the 20mm stator and 25mm bell.. with the gws 4040 .. if you have any two cell packs in the 700 to 1320 range.
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Old Aug 17, 2004, 11:05 AM
Why not Delta?
rysium's Avatar
Sacramento, CA
Joined Jun 2003
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Quote:
Originally Posted by AIR MOVER
I leave the trailing edge alone .. its set to hover over the boom.. when you crash the chances go up for the wing..
Therefore I gues, I put the rubber bands to tight over the wing. My wing doesn't move at all.

Quote:
Originally Posted by AIR MOVER
I use sq trailing edges as they help to stop flutter... this trick has been known for awhile and I found it helpfull..
Actually my buddy asked my if I designed the wing like that with the square TE (I'm known in my club for designing my own planes, so he thought I designe this one too). I told him, that I bought the plane like that, and I don't have a clue why it's square, but it came like this from the guy who knows what he's doing, so I'm not gonna mess with it. I don't have any flutter, even on th high sped dive. I need to measure the speed next time.


Quote:
Originally Posted by AIR MOVER
also you can use a small shirt button..
That's a good one. I like that.

Quote:
Originally Posted by AIR MOVER
If your willing try a 24g 12t Y 6pole
I'm flying now 15 turns delta with 3.5x3.5 prop on 3 cells turning 30k rpm on the ground. I don't hear it unloads much in the air. The plane is so slick that doesn't make much drag. And even it's so fast it's very quiet.

RysiuM
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Old Aug 17, 2004, 12:10 PM
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Houston, TX
Joined May 2003
749 Posts
I clock my Windbuster last Saturday. I was a little disappointed. The fasted reading I got was 67mph. It sure looks faster than that. I fly directly at the radar gun from a dive to reduce cosine error. When I would pull out, it fluttered every time. It didnít seem to hurt anything though. The guy using my radar gun may have misread. I know that it did 66mph with the previous hot motor and this new hot motor is definitely faster. Hmm, maybe the same top speed but faster acceleration. I will have to clock it some more this weekend.
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