somegeek

My Feedback: (2)

No doubt - good stuff!

That sounds like a sound plan. Also saw it mentioned to glue a sand paper 'washer' to the plate with the grit facing towards the prop. Could maybe even rough up the plate surface with rough sand paper?

somegeek

bleary

Gryphon,you are going sicko again as usual....good job.Sorry I missed your post about what I was doing with the Stryker lately...the answer is not a great deal sorry.
I have been playing around with Muliplex Delta wings of late,the Picojet,Microjet,and my latest love the Funjet.
Still running on 4S,but looking at a 5S setup,or even 6S...but have had the "Stop that, you will go blind" talk from the mrs bleary just lately,so keeping a lowish profile....
Trying to cram a 4S into the Microjet just now,thrust is insane with a 3000kv,but launch is the problem,will have to bungee that one I think.
Have a look at the Funjet,it's a Microjet on steroids,and a lot easier to extract serious speeds on 4S,and even high amp 3S.
I also orderd the same Mega you have,except the 3 version,with the 1800kv....I looked at the hotter one,but I have killed a coupla lipos lately,not from amp draw as such....but ambient here is over 100F,so heat has been a killer.
Must show some restraint......
Merry Christmas to all Stryker dudes,still the plane that always get's a fly.
Cheers,
Bleary.

somegeek

My Feedback: (2)

Went out and flew right after sunrise this am. Was 24ΒΊF and dead calm. Good stufff to fly in! I covered my battery cooling intake and the battery was barely warm after my flight. Flight times seemed a little shorter. Do cooler temps affect lipos in an adverse way?

somegeek

My Feedback: (2)

Back at you down under, Bleary! Have a Merry Christmas.

Mach62

Voltage falls off quickly under freezing point. But, if you can heat the battery up by running it hard before LVC is hit, it should not effect the time you run. It is more a problem at the start of the flight. If it is cold when you land, there is probably too much air flow to the battery during flight and you may be hitting LVC early.

somegeek

My Feedback: (2)

Thanks for the sanity check, Mach62.

r1derbike

I've heard charging/using the battery when it is very cold (battery at outdoor temperature) shortens the life drastically, reducing its overall charge cycles 'til it croaks...any shred of truth to this?

Charles

Mach62

I think that would be the case if you consistently fell below the critical 3v per cell but if you keep the batts in your pocket before flight and then they get warm within the first min of flight and you land with them warm and put them back in the pocket, then it is really no diff. than if it were not cold outside but I am no expert, I have only been flying since Aug of this year. Guys have told me to put a bigger prop on in the winter since the heat disipates so quickly one can afford to push the electronics more than summer. I guess I will find out because it gets -40 here and I am crazy enough to bundle up and fly anyway . . . Servos will probably freeze up . . .

Cali11

Pep Boys has that Bushnell Speed gun that SomeGeek posted for $109.Anyone know if that a good price?

maiden-crash

I dont know if this is true but in rcm magazine it was said that a lithium battery should never be left flat over night because a cell may die and now Im too scared to keep my lipo uncharged. Any one confirm this?

r1derbike

Just got back from flying in some fierce wind with the Stryker and got a scare/hoot with it! I was zinging inverted downwind on-the-deck and I pulled-up (well actually down) hard and looked in awe as my battery was ejected from the plane at about 30 feet up, and my Stryker came to terra-firma end-over-end, slow motion style. Tweaked a wing a bit on impact, but it is already fixed. That prop stops really quick when the battery comes sailing out![]

Battery survived with not a scratch/dent, must have been ejected horizontally enough, it rolled to a stop. Just wish I had been videotaping it...some kid behind me yelled, "Man, look at that, neat!". I said, "Yeah, cool, I want to do that again!".

I started laughing before my plane hit the ground, it was just surreal seeing it tumble to the ground so perfectly!

Anyone else had an battery ejection?

I'm going to secure it with a velcro strap, epoxied and pinned to the battery floor, before next flight! This Stryker is one tough bird!

r1derbike

I've seen the Speedgun II for 89.00-99.00 all over the net...free shipping.

You know...that is a true statement crossing all battery conventions. Chemical breakdown, voltage reversal, sulphated plates, electrolysis, leakage, and fire are just not worth it.

I don't even try to recover nicd cells anymore...if they've been abused and developed a memory, they are not fit for RC (or any other) use anyway!

Mach62

First Stryker C ejected everything but the motor in an inverted loop. I found the complete worthless hatch set and nothing else. Bout a week later, this dude comes up to me and says: "Did you lose a flight 25 something or other". The guy found my E-Flight Pro 25 amp controller! Still have not check to see if it works yet. . . Will be a big fan of E-Flight if it does. . .

r1derbike

My forward hatch was torn-out, with chunks of foam still attached to it. I've secured it to the Stryker with some CA around the edges too...

The nose cone was compressed a bit, but a magic-marker made it look like new again...better...it's shiny now!

Maybe Parkzone/Horizon will have the manufacturers strap the battery in, much like the typhoon has. Flyers are going to increase throws and raise 'ell with these birds. In fact, they just beg to be flogged!

I didn't like how the battery was only held in place with little foam compression rails, and thought after a few installs/removals, the battery would come loose and become a projectile...BINGO!

somegeek

My Feedback: (2)

Another way to install straps is to use a hot nail to slice some slots into the fuselage battery bay bottom side edges. I used a cotton swab to 'mop' some epoxy into the slots, coated the ends of the velcro pieces and then inserted. Very solid. Did this during the initial build. Read a few too many battery ejection posts. [X(]

Piece of pipe insulation at the back of the battery bay acts as a back stop for the battery to sit against to maintain the CG.

somegeek

somegeek

My Feedback: (2)

I was flying this afternoon at a school field by my place. There was a low wing civillian aircraft doing some flybys overhead around 200ft or less. My stryker was in his soon to be air space a few moments before that. If I hear a plane I usually look up to see how close my plane is... this time I was kinda freaked out regarding how low this plane was. Kinda trippy actually. I stuck to low altitude maneuvers until that plane was off in the distance.

somegeek

r1derbike

I like it! I've already got the velcro. Think I will use the two strips instead of one, as in your photo...thanks!

jeraldjcook

Here is the Bushnell radar gun for $89 with free shipping.

http://www.opticsplanet.net/buve10frups.html

Mach62

I think that is why Parkzone made their battery green so it blends so well with grass and you can't find it again.

A full-scale aircraft at 200 feet is just begging to dogfight! (ha, ha).

somegeek

My Feedback: (2)

No doubt. Think they'd help folks out and put orange or some other bright color of shrink on them. I've read where folks have attached a piece of 1" plastic caution tape a few feet in length to the battery and rolled up to place in the battery bay so the battery is easier to find upon ejection. Call me crazy but I imagine you'd want to simply prevent the battery from ejecting in the first place? Maybe there is something else there I am missing... [sm=confused.gif]

I'm all about safety/rules but I'd be lying if I said I didn't ponder what that dude's reaction woulda been if I flew off his wing tip in formation through part of his turn overhead or buzzed him. He wasn't going that fast.

Gryphon

Hi all,

3rd day of flying and I was brave enough to make radar runs on 4S.

I did only two flights, one on 3S and one on 4S. I will try the quick charge option on my 10cell TP charger next time. I think I will buy a TP 5000-3S Extreme battery and see how the plane flies with that. I will call that my Christmas present.

My friend had reported radar reading of 109 on 4200-3S prolite with 7X9 prop cut-down to 6.5" diameter on his plane w/same motor. On my plane I had flown with APC pylon 6.5X6.5 prop already and wanted to see how the APC 7X6 prop flew like and climbed. I was expecting about the same speed as 6.5X6.5 but better climbing and higher Watts static. Forgot to take watt reading this time and my advance was set on high. I had previously recorded the watts on STD advance.

After a few runs, I came in level but sideways a little and gave the radar gun a real good look.
My best friend of the last 25 years started screaming. Oh my god, faster than your 4S with dead battery. He kept jumping up and down, I'm like calm down what was the speed and get ready for another run, here I come.
Well he was so excited that he......Well I feel violated...oh well.
He finally says that I ran 111 MPH on my 7X6 with 3800-3S and high advance. Climbing was soooo goood, WWWWOOOOOWWWWW.
I said show me the radar gun reading, he held it up and it was blank. I guess he was so excited that he squeezed the trigger again. Well I never saw that reading. I got another reading in the 105MPH range later on, but not sure exactly what it was.

My brother was on his way and I had the 4S fully charged, I had the high advance, so I decided to go with the bigger 6X6 Graupner CAM 1200W instead of the 5.5X5.5 1100W setup.

I took a quick reading with full battery and high advance the reading was 1330W, 91.5A on 3300-4S TP and my MEGA 16/25/2 2650KV.

It seemed faster than ever, it was really fast. Climbing was out of this world. I had to start each of my radar runs over power lines and then come in low after passing them several hundred feet down from myself toward myself. Well the plane started to rise every time I hit near max speed.
I tried a few times and then decided to use down elevator. Not a smart thing to do low to the ground at those high speeds. I almost crashed….. no reading.

1) I never changed the low rates from 45/50% to 20% like I intended, that would have helped.
2) At home I saw a crack down the right side of the F-27C mount starting from the front and going back 1 or 1 1/2 inch.

I need to adjust the motor angle from front to rear.

motor never got hot, I was really on it most of the time, so in this cool air 1300W is not a big deal for this motor. At landing it felt like 70 degrees by touch. Battery was warm, so was the speed control.

***At some point motor cut off and I landed, ran to the plane everything was fine temp wise. I gunned it again and the motor did not cutoff, so I went right back up for a good long while.
I wonder why it cutoff. I know it is a 80A speed control, so maybe it was the self protection circuit. When I get a chance I will open up the side air vents to help keep it cooler. But I'm serious it was not hot when I ran up to it, 2 servo wires below it seemed warm, I will push those to the side when I get a chance.

At this point I will try and hit 115MPH on 3S if my friend's 111 radar reading of my plane was accurate at all. I've done a lot of bench testing. 2 props drew crazy amps on 3S.
Grish Products TORONADO 7X8 prop drew 102A at 1050W with 3800-3S battery.
APC E 8X6 drew 105A at 1050W with same battery.

So when I get the 5000-3S battery I will try that TORONADO 7X8.
It is weird how little the APC sport 7X7 draws compared to other prop types of similar specs. It draws 81A with my battery and 77A on 4200-3S prolite.
Other similar sized props draw so much more.
For day in and day out I think 65Amp will be a good choice. 35A motor rating right!!!!!!!

Bleary:
That MEGA 16/25/3 1700KV motor is what I have ran before, my brother has it, buggygovrom has it, GG has it. It is the most versatile motor. You can have it tame on 3S, very incremental control on power all the way up to 6S. If you back calculate from the number of cells that it is good for NiMh, you will see that it is good for just over 9S Lipoly. 3S-9S hell of a motor. Keep the amps below 60, below 50 will be even better. I have a spreadsheet of data for 3S & 4S on it and it included thrust readings for 4S. Let me know if you want it.

Mach62,
I think you have the same motor 16/25/3, so if you want the spreadsheet let me know and I will send it to you too.

Best if you guys ask for it in 2 weeks when I hope to have internet at my house again.

5S will have to wait, 4S is going fast enough for me right now and I can always prop even more.
A 5000-3S battery will be good so I have less down time in between flights.

I talked to Thunder Power and the guy said that with my chargers fast charge option they have tried both the Extreme series and also the prolite series and they are good for 600 fast charges before they are no good. I think I will do 1 fast charge per day, and rotate that between the various batteries from 1 day to the next.

I will post some low resolution pics below on the next post.

Gryphon

Gryphon

These are from my Stryker, all dark lines are C.F. tubes and C.F. Rods.
1 of the unclear pics shows how the F-27C scoop opened up looks.
**What you can not see is that there are C.F. strips (0.486 grams/inch) running across the trailing edge. They each have 4 cutouts for the hinges and they are epoxied to the T.E. and also have 3M extreme tape holding them in place.

Gryphon

These are from my buddy's Duct fan Stryker.Today was his real maiden flight.
He is running the MEGA 16/25/1 4800KV and WEMOTEC MINI fan on 3S-4200 prolite and Cc80A ESC. 77Amp as I recall

Climbing was fantastic, it radared at 100MPH with a half full battery and that was not even a great angle to the radar gun

***It does some thing I have never seen any Stryker do. When he does rolls (barrel rolls), the rolls are tight. The plane does not go to the side and roll around in a loop as it rolls. The plane still flies in a straight axis and just rolls while the center of the fuse is on the axis. AMAZING. It out maneuvers any prop Stryker. Well the ones that I have seen.


Enjoy the pics
Gryphon

bleary

Thanks for your valuable input Gryphon,when you get a chance I would like that spreadsheet if it is not too much trouble.
Seeing as you have gone the 5S route,after a bit of advice.I am looking at this battery,which is 3700 5S,or would I be better going for a slightly less capacity one.[link]http://www.rcozstyle.com/catalogue/batteries/lipos/3700mah/Hyperion-3700mah-5-cell-Pack-20-30C-740A-Continuous/[/link]
Also I have an external UBEC which is still in the packet,I bought it for another project,but I think that 5S may warrant it.How do you connect them up? heard tales of cutting one of the ESC wires...is this correct?
I have a coupla Towerpro 60amp ESC's which apparently are good for 5S,we will see I guess,they work on 4S tho.
Lately I have wrecked 2motors/1 ESC and 2 Lipos from mainly abuse,but also from high temps,as it is very hot here at the moment.I have decided to overspec a bit....you guys with the snow may get away with it for a while,we got bushfires here,which is a whole nother kettle of fish which I don't want to even think about...
Cheers,
Bleary.

Gryphon

bleary,

Job of the Universal BEC is to feed electricity to the receiver and servos instead of the small and fragile BEC that comes on ESCs, most of which are not rated to be used at 4S or above.
Universal BEC (UBEC) input wires gets doubled up on top of the same ESC connector that goes to the battery.
So on top of the ESC main wires lay the red wire on red and solder both on the connector and do the same for the negative.
The output end of the UBEC plugs into the battery port of the receiver. Some of the small receivers do not have a battery port, fine, then plug it into any unused ch. If you have no unused ch left then using a "Y" cable share a port with one of the Ch.

**That takes care of feeding juice to the receiver and radio. BUT SINCE THE ESC IS TRYING TO DO THE SAME......You need to take care of that issue.
You have some options:

1) On the ESC wire that normally goes to the throttle ch of receiver, remove the positive wire from the connector. Leave the negative and signal intact and tape the remove wire.

2) you can cut the positive wire (usually the center/red) and tape both ends.

3) you can attach a short extension and do either of the 1) or 2) steps above to the short extension.

4) BEST OPTION I BELIEVE: USE AN OPTO ISOLATOR. This needs no modification. Simply plug ESC wire to opto isolator, then plug the other end into throttle ch of receiver.

Job of OPTO Isolator? It helps reduce the extra noise from motor and esc from going into the receiver and causing interference.

MEDUSA Research makes both units. OPTO Isolator is like $16 or so.

They make the UBEC in 1.5A, 2A and 3.5A versions, most are made to have the output of 5V or 6V. 6V makes the servos faster and stronger.

***2A is more than enough for Stryker unless bunch of stuff is added like lights, camera, etc...
I was told that the 1.5A unit is also enough to take care of (2) Hitec 81MGs.

**I think MEDUSA may have an issue with some 2A units because they say if you have problems with voltage ripple to buy a Shotky Diode of 2A 35V rating. I did have issues with my last Stryker but I just removed the BEC and the problem went away.
This time I bought the diode, but my new Spektrum radio unlike my JR radio is rock solid, so I never installed the diode and I have no problems.

Mount the UBEC as far away as you can away from the receiver, before I had it touching receiver...a bad thing.
This time I have it stretched as far forward as possible, I dug a square in the foam on the side of the battery and installed it near the front of battery.

My Medusa Unit had said if installed close to the receiver to face the flat side of the unit towards the receiver. Read your owners manual.
__________________

I'm doing a bad thing right now. Since I was paranoid that I was going to have problems again, I didn't want to solder it on the ESC wire to battery without being sure that everything was o.k.. So I did the following as a test:
I took a male and female deans ultra connector and soldered the backsides together along with the UBEC wires.
Now the battery plugs into one end and the ESC plugs into the other end.
This way if I had any issues I could quickly remove it and also remove the OPTO as well so ESC could once again feed juice to the receiver.
Well everything has worked so well, I have not gone back to get rid of that contraption.
I need to remove the UBEC wire and solder it directly to the ESC. I already know that I do not need the Shotky diode.
Why have I done a second day and third day of flying without correcting that....I don't know.
Too lazy to do a quick unsolder and a re-solder I guess. Like I said I'm doing a bad thing.
Bitten once twice shy...and now lazy (DAMN THIS IS EMBARRASING).

Some UBEC have a second output (3 metal prongs, use a servo wire extension) which you can use so you do not have to do any of the steps 1) through 4), for example Medusa Research 1.5A BEC

I think I covered everything as far Universal BEC goes.

Now I will work on the battery question.

Hope I was clear; feel free to ask questions for clarification.
Gryphonn