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Old Nov 23, 2005, 11:31 PM
If it floats....sail it!
FoamCrusher's Avatar
Elk Grove, CA
Joined Sep 2002
4,154 Posts
Quote:
Originally Posted by modlflr
Thanks for the help. This gives me an idea where to start my settings at. I knew it needed some tweaking when %100 throw was at like 75 degrees or even more.
Mark:

Keep the high rate at 100%....if you can switch back and forth easily. My low rate is 50% for reference and still is a bit touchy, but that's the way I like it. Where you end up is also a function of the location of the CG. Further aft with high rates takes a steady hand.

The only thing I use the high rate for is doing axial rolls and a "leaf" stall landing. A quick switch to HR and slam the elevons over and it rolls faster than 1/sec.

To do a leaf stall/landing, turn into the wind, slow way down gradually killing the power and going to higher and higher alpha but not changing altitude. To do this keep slowly increasing the up elevon. Then kill the power with the elevons on full up. The plane will stop dead in its tracks and fall almost straight down will keeping the pitch level. It drops just like a leaf to a gentle landing. The CG must be dead neutral to have this work, but when it does it is a show stopper.

FC
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Old Nov 24, 2005, 09:24 PM
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cnc custom's Avatar
Joined Oct 2005
177 Posts
Happy Thanksgiving everyone.........
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Old Nov 25, 2005, 10:42 AM
Foamsmithing forever!!
crash test dummy's Avatar
Sugar Grove, Il.
Joined Aug 2004
2,992 Posts
Flight report...

Flew the Stryker today with the 6X.5.5 and 7X5 ACP props. The 7X5 had amazing thrust, as expected. I could point her up and just climb until it was a speck. The 6X5.5 has nice thrust to climb, but it is quite a bit faster. I like faster! I think the 6X5.5 offers the best of both worlds. The Himax 2815/2000 is faster in my F-16, it only has 25.5 inch WS. Theres alot less grag there. I think my 2815/3000 KV DD is faster in the Stryker. I run a 5X5 or a 5X3 ACP on that motor. But I really like the thrust of the larger 6 inch prop on the 2000 KV set up.

CTD
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Old Nov 25, 2005, 11:47 AM
If it floats....sail it!
FoamCrusher's Avatar
Elk Grove, CA
Joined Sep 2002
4,154 Posts
Quote:
Originally Posted by crash test dummy
Flight report...

Flew the Stryker today with the 6X.5.5 and 7X5 ACP props. The 7X5 had amazing thrust, as expected. I could point her up and just climb until it was a speck. The 6X5.5 has nice thrust to climb, but it is quite a bit faster. I like faster! I think the 6X5.5 offers the best of both worlds. The Himax 2815/2000 is faster in my F-16, it only has 25.5 inch WS. Theres alot less grag there. I think my 2815/3000 KV DD is faster in the Stryker. I run a 5X5 or a 5X3 ACP on that motor. But I really like the thrust of the larger 6 inch prop on the 2000 KV set up.
CTD:

Have you flown your plane with a Mega /4 on 6.5x4? If so, how do they compare?

I ran the 2815-2000 numbers through MotoCalc and it shows the prop badly stalled with a 6 x 5.5, but MC is not always correct with DD and small props.

When run MC with a 6.5x4, if looks OK, and when compared to the Mega it comes out with 5A lower current, 5 mph lower tip speed, 3.5% lower efficiency, 4.5 oz less thrust and 450 ft/min less ROC.....all for only ~$5 less than the Mega. Good #'s if you have Gen 2 cells that cannot push the higher currents the Gen4 cells can. Other than that, am I missing something here? Seems to me the Mega is still hits the sweet spot for this plane.

I understand that you used this motor because you took it out of another plane, but if you were going to buy a motor, would you buy the Himax over the Mega????

FC
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Old Nov 25, 2005, 03:31 PM
Foamsmithing forever!!
crash test dummy's Avatar
Sugar Grove, Il.
Joined Aug 2004
2,992 Posts
Mega or Himax

Quote:
Originally Posted by FoamCrusher
CTD:

Have you flown your plane with a Mega /4 on 6.5x4? If so, how do they compare?

I ran the 2815-2000 numbers through MotoCalc and it shows the prop badly stalled with a 6 x 5.5, but MC is not always correct with DD and small props.

When run MC with a 6.5x4, if looks OK, and when compared to the Mega it comes out with 5A lower current, 5 mph lower tip speed, 3.5% lower efficiency, 4.5 oz less thrust and 450 ft/min less ROC.....all for only ~$5 less than the Mega. Good #'s if you have Gen 2 cells that cannot push the higher currents the Gen4 cells can. Other than that, am I missing something here? Seems to me the Mega is still hits the sweet spot for this plane.

I understand that you used this motor because you took it out of another plane, but if you were going to buy a motor, would you buy the Himax over the Mega????

FC
If I was going to buy a motor I'd get the Mega, mostly cause I've never owned one and they get such hi praise. The Mega is 200 more KV over the Himax. The Himax is 79 bucks so it's only a little cheeper than the Mega. I thought the Mega was 20 bucks higher. I don't know if I can run 4S in the Himax, for some reason I think Himax only says 3S on those motors, but I'm not sure. I also buy Himax cause they are only 35 miles from my house and if I need service or parts It's not a problem, I can get parts in a couple days or I can just pick them up at will call, nice. They also have been very nice over the phone answering all my stupid questions. Talking to Himax is where I learned alot about E-Power systems in my early newby days. I'll have to try one of those 6.5X4 props, who makes them? ACP?

CTD
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Old Nov 25, 2005, 06:09 PM
If it floats....sail it!
FoamCrusher's Avatar
Elk Grove, CA
Joined Sep 2002
4,154 Posts
Quote:
Originally Posted by crash test dummy
..... I also buy Himax cause they are only 35 miles from my house and if I need service or parts It's not a problem, I can get parts in a couple days or I can just pick them up at will call, nice.......... I'll have to try one of those 6.5X4 props, who makes them? ACP?
CTD:

I hear that on parts. I broke the shaft on a Mega and it took about 4 weeks to get it back. Megamotorsusa ships them to CZ rather than repair them here. Shipping is cheaper than labor I guess.

The 6.5x4 is an Aeronaut. I can get them at my LHS, but you can mail order them from Hobby Lobby Part# HLAN2814 They are a good prop but everyone of them I have purchased was waaaaaay out of balance. They are so far out that sanding one side is not an option - it would have taken too much off one blade, so I coat the lighter side with clear nail polish to add some weight.
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Old Nov 26, 2005, 01:31 AM
Mega Demon Twin
Central USA
Joined Nov 2005
173 Posts
APC 6x4 vs APC 6x5.5 and other stuff....

3 weeks into my Stryker now! Loving every minute of it. 12 flights now with my Mega 16/15/4, 3s2000lp Kokam, cc esc 25, and APC 6x4.

Wanting more speed, today I tried the APC 6x5.5. A little faster top end. Seemed like better vertical???? Can't explain that....maybe wind. Both props unlimited vertical on calm day. Today was bursts of 20mph or so. With wind, coming off steep dive, my Stryker again stopped the air field patrons dead in their tracks as everyone watched it streak by!!!!!!! Batteries ran warmer with the 6x5.5 prop. Normally, on the 6x4, you can hardly tell I just finished a 10 minute flight session. So I believe the possible performance gain in the 6x5.5 isn't worth the shorter duration/warmer battery concerns.

I feel like I did right with my upgrades when everyone comes over to the table to see what exactly it is. The LHS even ordered in 5 Strykers based on the response. Ha!!!!

Like some of you, I want to be the fastest. So far, I am good. But I have only been to the airfield twice. I really made a name for myself though!!!

I don't know how I would put a 4s LiPo in my Stryker. Never seen one. Can anyone attach a pick? Would this help my speed increase desire?
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Old Nov 26, 2005, 04:30 AM
Mega Demon Twin
Central USA
Joined Nov 2005
173 Posts
Forgot to ask?

Has anyone researched the brushless motor called 450th? Not certain of the name, but I came across it a few weeks ago and it specifically says on their website about "passing all your Mega Motor friends."

I have another Stryker kit waiting in the box for the next "Faster" build.
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Old Nov 26, 2005, 04:55 AM
It's me Glacier Girl
Joined Aug 2004
868 Posts
Fly200,
Here's a pic a a 4s set up. Fits like a glove.
Note: if you go 4s on the 15/4 you will need a Ubec and at least a 35 CC.
Or if bucks allow go to the CC HV45 to handle the amps and volts.
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Old Nov 26, 2005, 12:35 PM
If it floats....sail it!
FoamCrusher's Avatar
Elk Grove, CA
Joined Sep 2002
4,154 Posts
Quote:
Originally Posted by SHELBY1
Note: if you go 4s on the 15/4 you will need a Ubec and at least a 35 CC. Or if bucks allow go to the CC HV45 to handle the amps and volts.
Shelby:

I have run my Stryker with the 16/15/5 on 4S with a regular CC45 and no external BEC without problems, but it was a cool day. It is pushing the ESC to the absolute limit, but a Stryker only has 2 servos so that is taking some heat from the BEC circuit off the ESC board, and total heat dissipation is the issue. The /4 would pull more amps and heat up the board even more. It may be doable, but you are right on the edge.

BTW, in checking the specs of the new CC HV-45 I noticed a discrepancy in the minimum cell count on the CC website. The individual product screen for the HV-45 says the minimum pack to run that ESC is 4S, and in the pdf Users Guide it says 3S. I posted that observation on the Castle Creations vendor's board asking Castle to comment. We will see what the "real" answer is.

Either way, Fly200 is going to need a thick wallet

FC
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Old Nov 26, 2005, 04:30 PM
Foamsmithing forever!!
crash test dummy's Avatar
Sugar Grove, Il.
Joined Aug 2004
2,992 Posts
Thick wallet, He He! Thats why I havn't gone to 4S. My wallet is paper thin. Plus Santa will be coming to rob me very soon!!!

CTD
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Old Nov 26, 2005, 11:45 PM
If it flies do it!
BoboG's Avatar
Mount Vernon, WA
Joined Oct 2005
95 Posts
I run a Mega 16/15/4, a CC-45, with a TP 3s and an APC 6x5.5. I have noticed that the battery tends to get a little warm running TWO the full flight time but everything else seems to be very cool. The battery is about as warm as my pocket on these colder days. I do run with air intakes just to be safe. I will say that my Stryker does scream and will go vertical until it is nothing more than a spec. I am hopping to get in my TP 4s within the next few days and look forward to seeing what the plane can do with the additional power of a 4s. I just picked up an Astro Flight 109 Lithium Charger today so now all I need is the pack.

Some side notes:
Where I fly, the majorities of the people fly gas planes and kinda snub their noses at the electric when I pull it out of the car, but while they are still trying to get theirs to start I am in the air. When I finish flying they all seem to come over wanting to know what it is. They are so amazed at it that some of them are looking into going electric now. kinda funny if you ask me. I canít wait for them to see what the 4s can do.

I have thrown together a quick web site with photos and video of my Stryker, A.K.A. Lawn Dart . In the future I will add more photos and videos as well as some of the helpful tips I have learned along the way.
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Old Nov 27, 2005, 12:25 AM
Mega Demon Twin
Central USA
Joined Nov 2005
173 Posts
FoamCrusher, CTD, Shelby1, & forum: "Lets take it up a notch"

Let me see if I can digest all this..............nope, I can't.

What does the Ubec do? How much?
HV45? How much?


FoamCrusher, CTD, Shelby1 and others: If $$$'s were no object, what is the next Ultimate Stryker Build possibility? I have another wing sitting here waiting ready for upgrades. I know there is more speed in my wing possible. If the above 4s set up with HV45 and Ubec is all we can do, then fine. But if there is anything new out there, like the 450th motor, let me take care of the expenses, and you guys give the upgrade directions!!!!!!

I have to think there is only a limited number of things we can do with the little space we have to put things in.

Shall we get started?
- keep it brushless, 7 minutes of flight at least, mostly at high throttle, and no major changes to current design. Speed being the main interest. Possible retracts for landing gear. Single motor design.
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Last edited by Fly200; Nov 27, 2005 at 12:28 AM. Reason: no title
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Old Nov 27, 2005, 12:32 AM
Mega Demon Twin
Central USA
Joined Nov 2005
173 Posts
OH, thanks for pic of 4s Shelby1.
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Old Nov 27, 2005, 01:23 AM
If it floats....sail it!
FoamCrusher's Avatar
Elk Grove, CA
Joined Sep 2002
4,154 Posts
Quote:
Originally Posted by Fly200
What does the Ubec do? How much does it cost? How much is the HV-ESC?
The ESC not only controls your motor, but it also drops the pack voltage down to about 5V to run the Rx and servos. Like any electrical device, it can only deal with so much power (combination of voltage x current) droppeing the pack voltage down and running the servos before it overheats and shuts off. The number of servos increases the load on the BEC as does increasing pack voltage. Each ESC has a limit of the number of servos it will handle combined with a given pack voltage. Most ESC's cannot go above 3S lipo voltage at all. The CC35 and 45 can go to 4S but only with two small servos.

If you need more voltage for your motor, you disconnect the ESC's BEC and run a separate BEC, or run a 4-cell NiMH pack just for the servos and Rx, but you will need an ESC than can deal with the higher pack voltage for the motor.

Most ESC's will not run even as a bare ESC at more the 4S, but CC has created a new line of high voltage ESC's, named appropreatly enough HV-45, HV-80 and one even higher....I think HV-100, for BIG planes with BIG motors.

The CC website says the HV-45 will retail for $160 An Ultimate BEC (brand name) runs about $35 from Hobby Lobby.

FC
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