RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

You're the best, Gryph :D

My batteries:

2 off parkzone 3s 2100
2 0ff TP extreme 3s 2070
2 off rc dymond (no-name) 3s 20c 1800
2 off dymond 3s 20c 4000

All batteries have seen many flights and are always balanced charged on the parkzone 2amp 2-3 cell charger. The first three pairs are (were) usually flown in parallel for the 16/25/2.

The plane is the old 'stock' heavily reinforced and heavily worn frame. Stock elevons. The goal is too run a smaller prop at higher RPM by going to higher voltage. The 16/25/2 is limited to 4s. As you can see, my batts are well suited to 6s.

There was a tremendous drop in power between the /2 and /3 that I did not expect. I am off to the garage to install the E-Flite 60Amp Pro Switch Mode I bough today. I am all set to go 6s. Looking forward to the sound of much higher RPM

And I WILL remember to program the ESC. It doesn't have a lipo autodetect [:o].

~Bub

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

Just back from my shop and the successful build of my new 6s rig. The 16/25/2 roars with a APC 7x5E on 3s. The /3 screams on 6s. Tested it with full throttle using a 5x5. Papers and debris blowing everywhere. (I really need to clean my shop.) The motor and ESC barely warmed up.

Maiden tomorrow with the 6x5.5. ;)


~Bub

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

I did remember to program the ESC for 6s

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

BubbleGum,

16/25/2 is a 2650KV motor, meaning 2650 revolutions per volt with no prop attached to motor (no load).
So you can see that the KV is just a nominal value, and not an exact number to go by.

16/25/3 is a 1700KV.

Generally, apples to apples, all things being even; the following holds true.

Lower KV more torque so it swings a larger prop given a certain voltage.

Higher KV has less torque but higher RPM, so it swings a smaller prop at higher RPM using the same certain voltage as last example.
____________
Higher KV motors have lower resistance and can handle higher amps.

Lower KV motors can handle higher voltage
______________
16/25/2 at 4S and high amps will make similar power as 16/25/3 on 6S. Since similar power, they will swing the same prop at similar RPM.

Swinging a too small prop will be a bad combination given the drag of the stock Stryker Airframe. The small prop can be swinging so fast that if you calculate the pitch speed, it will be 150-180 MPH or more but the plane may not go over 110-125 MPH. Like a car spinning its wheels on ice and not going anywhere fast.
So a balance of thrust and pitch speed is needed for a given airframe.

16/25/3 1700KV at 6S will spin a 6" prop way faster than a 16/25/2 can on 3S.

16/25/3 on 6S will be similar to 16/25/2 on 4S and if you had one combination it is not worth a switch to other combo.

In the last combination above the 4S will need to flow 50% more amps to make same power that is why the cells will be larger.

6 smaller cells or 4 larger ones.
For comparison:
6S-2500 will have same weight as 4S-3750 given same manufacturer cells of same “C” rating.

Given available cells I ask guys running 16/25/2 on 4S to get 3850 cells, they will have more of a safety buffer compared to guys on 16/25/3 6S-2200 if making the same power.

I believe there will be more power made with 16/25/2 on 4S-3850 compared to 16/25/3 on 6S-2200.

Good reasons to run 6S-2500 will be longer run times and more power and longer battery life while running cooler compared to 2200 cells.

If your 16/25/2 motor is in good shape, and you wanted small prop at high RPM, it would have been much cheaper to buy 4S-3850.....I think you would have had a little higher RPM as well.

Rough calc shooting off the hip assuming same voltage per cells.
2650KV*4S/6S=1766 KV will be needed, but you are running 1700KV.

Assuming even a little higher efficiency for 16/25/3 still not enough difference to be worth the switch.

Old saying: 6 of this or half dozen of the other....

If your 16/25/2 is damaged, then you can do one of 2 things with Ken the distributor of MEGA motors in USA.
1) Have him send the motor to manufacturer for repair, long wait and pay for fix after repair
2) Do his exchange program with another motor that has been previously repaired and sitting on shelf for $45 (exchange program).

Want extra high RPM????????? 16/25/2 on 5S-3300 but it will not fly faster than 4S-3850 even on same amps because prop size gets too small. 33,000 to 38000+ RPM depending on prop.

For high speed don't go below 6" prop for a good combination. That is why 16/25/2 on 5S for Stock Stryker is not a good combo, but should be awesome on the Funjet.
________________________
Back to 16/25/3;
A good 5S will destroy a 6S with lousy cells like your parkzone 3s 2100 (if they are the same cells that I am thinking of 12C????). I would much prefer 4S-3300 25C compared to 6S-2100 12C.
These may be worth running with small prop as last flight of day using a smaller prop, Maybe even when other cells are charging. They might swell on you.

I doubt (2) dymond 3s 20c 4000 will fit...and too heavy.

rc dymond 3s 20c 1800 are a little border line, you will need a wattmeter to make sure you are propping right. Because border line, I would only thrust MOTOCALC simulation so far.

(2) TP extreme 3s 2070 will be GREAT.

Did I jump around too much in this post...if so that is what happens when watching TV on the same computer that you are typing on....LOL.... :D

Ask for clarification if needed….If I screwed up somewhere let me know.

Gryphon

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

How do my stabilizers look? Wondering if I should remake with more height in the rear. Currently reading my DX7 book cuz I can't figure out how to make it work. Any help appreciated. ~Ronrico



http://i130.photobucket.com/albums/p...Stryker033.jpg

http://i130.photobucket.com/albums/p...Stryker055.jpg

It's 2:30 A.M. Do you know where your Lipos are?

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

ronrico418,

Check your PM inbox in a few minutes.

Gryphon.

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

Thanks Gryphon.............Again


http://i130.photobucket.com/albums/p...Stryker069.jpg

http://i130.photobucket.com/albums/p...Stryker080.jpg

http://i130.photobucket.com/albums/p...Stryker084.jpg

http://i130.photobucket.com/albums/p...Stryker087.jpg

http://i130.photobucket.com/albums/p...Stryker088.jpg

http://i130.photobucket.com/albums/p...Stryker003.jpg

And a couple pics of my baby w/ thread jacking intended lol

http://i130.photobucket.com/albums/p...Stryker073.jpg

http://i130.photobucket.com/albums/p...Stryker074.jpg

New work bench

http://i130.photobucket.com/albums/p...Stryker067.jpg

props to RaNDY

http://i130.photobucket.com/albums/p...Stryker068.jpg

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

Quick comment on the Air Thunder Batteries only, will respond to all questions separately:

I have three friends who have started to use these (for us) new packs on medium sized 3D helicopters, and so far they are very happy with the Air Thunder packs and are recommending them.
The discharge data reminds me of the new A123 packs, safe to take down to 6 volt for a 3s pack...

Does anyone have the weight on Air Thunder?

Wonder what's coming next?

Styker_Viking

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

Some more

http://i130.photobucket.com/albums/p...Stryker006.jpg

http://i130.photobucket.com/albums/p...Stryker005.jpg

http://i130.photobucket.com/albums/p...Stryker034.jpg

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

I would agree with your friends. I have a couple of Air Thunder 4s 25c 2200's and am real happy with them. The 4s weighs about 9oz on my cheapo postal scale. [8D]

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

Hey ronrico:

Great looking build.

Where did you get the canopy from?
Your Elevon design is also very interesting!

If it was me cutting those vertical fins, then I would re-cut the top of the fins so they are at least horizontal.
The reason being is that a negative tip will cause turbulence and drag, and I know that I don't want that, how about you?
Does that make any sense to you?

DX7:
Basically only a matter of selecting correct wing type ("Delta" for a Stryker, see page 39-41 in the manual) and plug in Left servo to AILE and right side servo to ELEV.

Good luck, and keep up the good work and reading.

Stryker_Viking

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

All those numbers are posted on thier web site for the specific batteries. I know a lot of people are skeptical about these batteries but so far everyone I know that is using them, and including me recently are liking what we see. They are cheaper and seem to really be holding up to the promise. Only thing I don't like is I can't find them locally in stores, which I sometimes like to do when in a pinch for a new battery. I just started using one which was a loan from a friend and so far I can't tell the difference between them and my Thunder Power V2's and Flight Power 25's. I may soon be buying a few sticks very soon to test on my F-16 using 4s and 5s.

Jim

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

jimweda,

Thank you for the comments on the battery.



Air Thunder Batteries web site:

http://www.airthunder.com/catalog01/index.php?cPath=22

They seem to come only in 2200 mAH and 5000 mAH, both are 25C/40C.

From what I can see they seem to be on par with quality 25C batteries as far as performance, weight, and maybe 15% cheaper price.

Off top of my head: same weight as FP and NEU, but only a little heavier than TP.

*** Looks like real good stuff.


I have too many lipos right now to buy any. By the time I'm ready to buy some, I'll be reading about what you guys thought about them after long term use. Really sounds like it is well worth the money. Who cares about few % more or less power here or there, given the Low Voltage cutoff advantage.


Later,
Gryphon

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

That was perfectly clear, Gryphon. In fact I should have figured that out cause I am a mechanical engineer. But with so many different nomenclature (Neu motor 1107 series is the same size as Mega 16/25 series, etc.) I can at least put some faith in what the Kv number means. You framed the Kv concept quite well for me.


The two maiden flights with the Mega 16/25/3 and E-flight 60A pro switch went quite well. I'll compare it below to my previous Mega 16/25/2 with a Castle Creations 80amp below ('old rig' hereafter).

The wind was at 20+ mph, as if that mattered :D.

First flight with the two 12C 3s 2100's and an APC 5x5E. Taxi was fast and the bird took off in about 50 feet (remember I have take-off gear). The plane flew level at a slightly higher speed (my guess) as the 16/25/2 motor with a 6x5.5E prop on the same two batteries. But vertical climb was not unlimited.

I flew at around full throttle for the full flight. The flight was not timed. When the batteries started getting low the plane told me so because the motor started to make a stuttering sound. This is one of the benefits of the E-flight ESC over the Castle Creations. The CC ESC would just die.

Landed and immediately checked for heat. Batteries cooler then compared to the old rig. ESC cool to the touch, cooler then the old rig, motor warm to the touch, cooler then the old rig.

Second flight was with two thunder power extreme 25c 3s 2070's and the APC 6x5.5E. (Quite a leap, I know) Take off was almost instantaneous at 3/4 throttle. I pulled back to 1/2 throttle and turned around for a high speed pass. At full throttle the ESC once again stuttered. I repeated the previous and tried another full throttle. No stutter this time. I figure that batteries warmed up.

I think the speed was at least as high as the same batteries in the old rig on a 7x5. Climb was not as fast though. Which all makes sense given the kv, prop, voltage, etc.

I burned up the sky for a while at varying amounts of throttle.

Interesting side note: A trio of coyotes on a hill nearby began howling to my plane when I started varying the throttle. The plane sounded like a howling coyote!

Then after a while, the motor stuttered. Batteries are done. Landed the plane and checked the temps. Batteries slightly cooler then the old rig. ESC still cool. Motor hotter then the old rig, around that of hot coffee cooled off enough to slurp.

I give high marks to the E-flight 60amp pro-switch. Just hope it doesn't burn out on me like my like my old 40amp v2 did after only 50 flights

The Mega 16/25/3 performed as I expected. It likes to go fast. Though it will need a heat sink when I series up the two 4000's [8D]

:D


Happy Flying


~Bub

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

BubbleGum,

Thanks for the detailed flight report.

Your CC ESC was probably set of hard cutoff and this new ESC on soft cutoff. So it was just the settings.


With batteries cold, also take it easy after the initial take off for a little while. As you said the battery needs to warm up. Mean while if you stay on it like you did, I believe that shortens the life of your batteries and they will also make less power in future flights.....so be nice to your batteries.


With the 16/25/3 6S TP extreme, I would have expected easy 10+MPH advantage over 16/25/2 on 3S 7X5.

Were you flying your hybrid Stryker?
How about a couple pics showing the locations of your components under the hatch?


Thanks again BubbleGum,

Gryphon

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

I Assume the batteries were in seires? I Have the same setup going together mega 16253/ eFlight 6o pro switch. I am about to order batteries (like right now) so I just wanted to clarify.
I'm looking at the neu 30c series they have a 2100 at 190 grams 72.50 a 2500 at 221 grams 85.00 allso looking at air thunder 2200 25c 190 grams 2 for 118.98. Are you serious about the 4000's because I was worried about the weight of the 2500's. I Hope my fuse comes in tomorrow I am anxious to get started.

This thread is AWSUME thanks a bunch everyone!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!,

JDXX

XX is for my bike, Super Blackbird 1100 XX
modeld after the Lockheed SR71, Another rocket,
crazy power is the only way[>:]

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

I see Gryph's post now so they were in series. Sorry I was typing and correcting errors bit slow at it.

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

See next post

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

JDXX,

Main reason I asked BubbleGum to post pics was for you to get ideas. He has good experience building Strykers.

***Without having considered the Air Thunder Batteries due to my lack of experience with them, I wrote this post.

Don't worry about the weight of the 25/30C 2500. Even if it means you will be balancing further forward compared to stock C.G. point (dimples under the body in the handle area).

***It looks like you cannot run (2) 3S-2500 30C NEU packs side by side, they are too bulky to fit. You can wait till fuse arrives and measure and compare to NEU site specs. Now you can fit them end to end but you will most likely need to place ESC in the wing on side of hatch. I did that to a receiver once.
Two packs side by side gets less cooling, because there is less surface area exposed to moving air. But BubbleGum has shown that they will run fine, so have others before him.

*** For simplest install and about max power, consider the (2) Flight Power 3S-2500 25C packs in series to make 6S.
Specifications are as follows:
FPWP0333, 3S, 11.1 2500mAH, 7.4o.z. (208.3gram) 5.1" x 1.6" x 0.9" (129.7mm x 40.2mm x 21.7mm) 25C
two side by side will be 40.2mmX43.4mm, that will easily fit. My TP 5S-3300 25C battery below is longer and its 48mm width can be fit vertical(my Stryker) or horizontal(my brother's Stryker and Stryker_Viking's), so a battery that is 48mmX48mm can fit and you setup be under that size.
Also if set to make same power as (2) 2200 25C packs, they should run a little cooler than 2200 cells.
The 2500 25C packs get my vote given their size and capacity. Air Thunder Batteries are viable option but you make the call and check their size too.

If you want to install the two 30C packs end to end, it can be done. I am installing a 195mm long 570-590 gram battery in my Stryker, but my ESC is going in the wing....question is how easy you want the build?


The extra weight causing more of a nose heavy condition will mean the you will require less down elevator to get rid of unwanted nose pitch up at above 115 MPH and will fly faster than otherwise given same power due to no drag from down elevator or less of a drag.
The 2500 battery will cause you to make more power with same prop.
Also due to 2500 battery you can prop more aggressively for even more power.
you can get 1/2" larger prop for more climbing power.
Pitch can be decided on depending on max speed VS flight duration for full throttle level flight.
APC pylon props are 6.5" diameter, run 6.5X5.0 after 5+ flights on battery if you want the motor to do its best.
Use APC sport 6X3 for initial battery cycling (2 or 3 flights 70-75MPH), then APC E 6X4 to get used to more speed 100+MPH and condition the battery further.
APC E 6X5.5 for 120+ MPH runs and great climbing.
APC pylon 6.5X5.0 for 120+ MPH flights and JAW dropping climbing if using 25C 2500 cells. These cells can handle 70A range current flow easier than smaller cells and will last longer while making more power, also fly longer compared to other cells.


My 16/25/2 flew fine with this battery: (use it for size and weight comparison)
TP 3300-5SXV, 18.5V, 5-Cell, 442 grams, 32x48x148 (mm), $189.99
My UBEC was inside wall on one side of battery. My receiver's second small satellite receiver (for AR7000) was in the side wall on other side of battery.
___________________

BubbleGum,

Are your (2) TP 3s-2070 Extremes placed end to end or most likely side by side?


Gryphon

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

JDXX,

http://www.airthunder.com/catalog01/...products_id=33


AirThunder packs are too bulky to fit side by side.


Dimensions: 30 x 37 x 113mm

Two packs side by side will be 60mmX37mm.....it seems too big to me, but have at it if you want.

End to end might also mean that receiver will also go into the wing not just the ESC...226mm long, wow....but do-able.

If end to end, I would do the 2500 30C NEU packs instead for more power and longer flight and to keep receiver under hatch.


Have fun,

Gryphon

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

LOL, that is an ugly sight. My bird doesn't even have a hatch. Just duct tape and bailing wire. 'Amp Pig' is well past her prime. I'll post old and new pics. 100++ flights.

'SU27ish' version 2 is still in the hanger


You will be pleased on 6s, JDXX

~Bub

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

BubbleGum,

Were your (2) 3S batteries side by side or end to end when used with your 16/25/3?

Gryphon

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

Gryphon are you ready to get to work? Call me if you are 242am est I want to see if we can get my Medusa meter to show me some wattage tonight ~Ronrico

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

ronrico418 ,

Ring ring...your phone will ring in 10 seconds. I had fun setting up your trans over the phone last night.


Gryphon

RE: F27 STRYKER -Way Past the Limits Part 6 -Go deeper in to the Dark Side...
 

SV~ Thanks for the compliments. Means alot coming from someone with such amazingly creative builds. Your birds are definately inspirational!!!

The canopy is cut down from my Hobby Lobby V-Diamond I'll post pics in an hour with new nose!

I will re-cut the stabilizers as you suggested. I didn't like the way it looks and what you said makes sense.

As far as the DX7 goes Thanks to Gryphon who walked me through it last night

Thanks again to you Stryker Viking