Arcteryxxx

Forever is best described by the time you spend checking USPS tracking when you're waiting to receive parts from other continents to finish your project...

Gryphon

Arcteryxxx,

Knowing that tomorrow or next day there will be (3) new 16/40 motors showing up .....well, I can wait a little longer......oooooohhhhh yeah.

Tracking only shows them coming into USA through New York as of Friday/Sat last week and no update since. [:-]


1-2 more days....I can wait.

_____________________________________________

murdnunoc, better get ready!!!!!



Gryphon

Arcteryxxx

Guess you're right about that
I'll be checking my local HW store for some M2.5 on friday!
I'm always sceptical about measurements and specs: when I received the mount from Gary (customrcparts), the diameter of the screws was as I expected but the "pitch" was higher than European Standard....
Maybe I cried "wolf" out loud for no reason at all here, but I really would hate to mess up my new motor by forceing something into a hole it's not ment for.

Best regards,
Arctic Stryker Pilot

gabe_tuft

Ok, well I solved the flexing problem by laying in the cf tubing along the rear of the plane - not quite on the trailing edges, but rather completing the triangle that the leadin edge reinforcements make (following Mopar's build). This is the suggested method on the darkside Stryker thread. I also painted the elevons with 15-min epoxy.

Now that there is no flex, all the force is directed at the ailerons, and the flutter is worse than before (straight line). I can't even get past half throttle now. There is some play in the servo horn that may be causing it. They are JR servos so I thought they would be ok. I think it's time for metal gear servos and metal servo horns. At this point, balsa elevons also seem like a must.

I may just retire this Stryker until the Darkside Build is done. The trailing edge of the fuse is pretty banged up. I'm not even sure if I could get the balsa elevons on it at this point.

Live and learn.

moparmyway

Gabe,
You do NOT need metal servo horns. You just need DuBro HD ones. Look here

http://www.dubro.com/hobby/ecatalog/dubro/s00050.htm

Your flutter.........can you post up some pictures of that build so we can see what you got going on there ??

gabe_tuft

Sure thing, I will take some tomorrow morning and get them up here.

gabe_tuft

Here's the pics:

Overall view:


Shot of the pushrod & top of the wing:


Shot of servo horn & pushrod:


Motor & mount from CustomRCParts.com:


Shot of my "not-so-pretty" underbelly:


Newly installed CF on trailing edge. Its not quite flush - it was my first attempt and the glue dried faster than I anticipated:




JR Sport Servos, epoxied in:


Wing:


There is some play in the elevons if I move them with my hand. I'm wondering if the servos are allowing this. Also, I was wondering if the actual trailing edge of the wing is deflecting and causing the fluttering. I could run additional CF spars near the trailing edge, maybe 2 or 3 inches in. What do you think Mopar?

gabe_tuft

Figured it out. I test flew the Stryker after installing additional spars along the trailing edges and got some sever aileron flutter at 1/4 throttle - but only on one wing. Turns out, the elevon hinge had ripped all the way through on the bottom side on the inner two hinges. After further investigation, I noticed that tears wear starting on the other wing hinges as well. Looks like I need some new elevons. It may not be a pretty fix since some of the hinges had already ripped through the foam and I used CA glue to fix that.

moparmyway

The pictures wont show when I click the links.
I KNOW that the trailing edge moves ALOT at higher speeds, and will allow major flutter if you do NOT install some CF very close to the trailing edge.
I think a few posts back I suggested that you embed some .210 CF tubing about 1/2 inch from the trailing edge. You MUST follow the trailing edge. If I understand your explanation correctly, it seems that you have a left to right CF strip that does NOT follow the trailing edge (TE). You really need the CF to follow the TE the entire length of the TE.

Having those hinges rip on you should be a great hint for you to upgrade now to balsa elevons and bass TE.
You will still need the CF to follow the TE in addition to what you have already installed.
Can you get the pictures to load directly to the forum without the photobucket being used ?

The first picture shows CF a little too far away from the TE, and as a result, she has been glassed to eliminate the flutter.
The second picture shows a CF strip following the TE very closely along the entire length, and it works MUCHO BETTERER !!!! (NO Glass needed !!)

gabe_tuft

I did that originally but the pics were large and it seemed rude o me to post them that way. Working from my phone now. I'll get them up in a bit.

I think I'm gonna retire this Stryker and just wait for the Darkside build. Also, just lost my Habu in a jungle with no way to find it or retrieve it. Pissed.

moparmyway

DEFINATELY get rid of those stock clevises !!
They will break on you when you are in the air and least expect it !!!

Is that an E-Flite motor in the Trojan ?

Is the T-Rex 450 SE a V1 or a V2 ??

The larger the pictures are, the better !!!!!!

gabe_tuft

LOL! You are observant!

EFlite Power 25 in the Trojan mounted on one of Gary's mounts from customrcparts.com. CF reinforcement in the wings, horiz stabilizer, and the elevator.

T-Rex 450 v2. Waiting on a new tail piece.

I've got the Dubro clevises and all the hardware recommended by your build and by Gryphon set aside online in my shopping cart. It's all getting ordered next Wednesday.

Bought all the balsa a ca hinges today - enough for 2 strykers. I think I'm gonna try to salvage this one, or at least use it as a test run for the construction of the elevons.

gabe_tuft

Mopar,

I started my build and when I attached on of the balsa elevons, the bottom doesn't quite line up with the trailing edge. Should I just file it down flush or should I pull the bass wood off and be more careful where I place the hinge slits?

moparmyway

File everything smoothe so the airflow doesnt want to stop and hang out for a slow 2 count.

So long as you allow the air to transition from the wing to the elevon(s) and then out and away from the Stryker without hitting anything (like a hanging elevon) then you should be just fine.

Definately paint some HARD epoxy on the balsa elevons and the Bass wood AFTER you have filed everything for smoothe airflow.



Next time you make your way to NY and can bring some of your toyz, you godda let me know, I have the perfect field if you got the time.

gabe_tuft

No slow 2 counts here!

I'll definitely let ya know when we come to town. As far as bringin my toys, I have yet to find a case for the Habu or my Stryker. Let me know if you spot one.

moparmyway

I am in the same boat on this one.
I have heard of some dedicated Stryker Dudes who bought some suitecases to transport their Strykers in.

Even if you cant bring the Stryker, if you can bring some other toyz, the field will allow anything you got to get up in the air. The more notice you can give me, the better. I understand your schedule can be pretty hectic, just try to stay injury free so you can try out some of mine.

100 posts...............wow that went fast eh ???

Gryphon

Hi all,

Thunder Power will put out a new charger in the next month or two.

I think it is called TP-820CD

"D" stands for Duo

It has 2 completely separate sides to it....each with 400W max regardless of what is getting charged on the other side.

It is like (2) 8S chargers connected at the hip.

What is max AMP rating??? I believe that to be 20A max judging form name of charger and comparing that to previous chargers.

Of course it will not be able to maintain 20A at higher cell levels....remember 400W max.

400W / 20A = 20V


Above 20V, it will not be able to maintain 20A........so somewhere above 4S max AMP rating will fall below 20A.
The higher the cell count, the lower the max AMP can be.....same 400W maximum.

I didn't get the price, we will soon see.

Remember it can charge up to 8S on one side while it is charging anything else with different cell count and charge rate on other side.


AWESOME!!!!!!!!!!



Gryphon

Arcteryxxx

Mopar: I am looking for a procedure for cycling new LiPos. Gryphon told me you posted someting about this but I haven't been able to find it. Could you please send me a link?

Gryphon

Arcteryxxx,

I'm not so sure I said that he(Mopar) did the post(s). I said to read his thread.

It might have been me who posted it.


I have done this numerous times in part 6, and part 7, and most likely in this thread (part 8).


Part 7 thread:
http://www.rcuniverse.com/forum/m_7464076/tm.htm


Part 6 thread:
http://www.rcuniverse.com/forum/m_6069877/tm.htm



Gryphon

Arcteryxxx

I finally found it on page 24 of this thread.

Sorry for nagging....

Gryphon

Arcteryxxx,

Add to those instructions:

First charge a pack because they come half full and need a charge before any discharge occurs… go to 100% charge, not 90% charge options or similar.
Do not discharge more than 2/3 of your pack capacity (mAH).....or go below 3.6-3.7V range per cell under load , which ever happens first at 3C-5C discharge rate…. start around 5C and it will maintain above 3C....of course that is at full throttle.
***Do not over discharge the pack on first cycle or it will be very bad for your pack.

Charge pack again.

Discharge the pack again at 3C-5C for cycle #2.

note: ...5000 mAH pack = 5AH, so 3C-5C=15A min, 25A max....at least try to get close....I have broken the tips of APC E 4" range prop in past on purpose to drop the amps that low on 2650KV motor, check amp, rebalance till you get close to 25A, write on prop: "SAVE" and place in tool box after these two cycles for next time.

Then do a cycle or two at higher amp range such as 50-60A for #3, and something more for #4 cycle.

I wouldn't do a high AMP prop test without doing those 4 cycles at minimum.....Mopar does more cycles.

But to skip out on the above will make sure pack is not at its best.

For Cycle #3 and #4 don’t discharge past 75% capacity or so...or 3.5 Volts per cell under load whichever comes first.


***Do not think for one second that at part throttle, the amps are less than max….that explanation will be saved for tomorrow if you or anyone asks.
Also you will be heating up your ESC at part throttle.

Remember to stop every 200 mAH and cool the motor back down to room temp….I use bag of ice for much shorter wait times.
Write mAH for each time you turn on throttle on paper so you can keep track of the running total….if in doubt, it is better to keep it to fewer mAh discharge versus too many mAh discharged.


Questions?

I’m sure in one of those threads I’ve done a better job on the write up….but that is all I can do at 5:30 a.m.

***If you had Castle Creations ESC and could set custom cutoff voltage that would have helped make it good proof, not that you cannot handle it but it is just another added insurance….Eagle tree could display running total of mAH and voltage under load…so can a wattmeter….but keep mAH totals on paper.


Good luck

Gryphon

Gryphon

Arcteryxxx,

I forgot to mention that you can use your lowest KV motor so prop selection would be easier and it'll turn at less RPM and with less noise!!!!!

If motor is way smaller then keep it to 150mAh or whatever is needed before stopping to cool down motor.


Maybe you want to reverse direction of rotation on motor to have prop blow air onto motor ....it can help a bit.


Gryphon

Arcteryxxx

Thanks!
I figured that out. I've been rigging a Turnigy 2836/2350kv outrunner for the job with a TGS 4.5*4.5. Maybe I have to do some tip-trimming on the prop, and I'll be monitoring the wattmeter closely. Also using the stock Stryker C esc for cycling as I've finally mounted the Plush80 in the bird for some 3S testflights. The only thing missing now is the M2.5 screws that should be arriving at the local hw store tomorrow.
A strange thing about the M2.5s: The manual (small sheet of paper) that came with the motor stated that M3 should be used on NEU 1112 and 1115 but my motor shurely is only M2.5. Another thing: Mopar said not long ago that the screws should have 4mm travel into the motor. Since I use Gary's mount i ordered M2.5*6 screws. But here is my dillemma: Garys mount is 2mm thick and so is the end plate of the motor (with the mounting holes). This leaves 2 mm travel further in to the motor for the screws and it seems like they'll just about touch the windings. Right now I wonder if this could be right or if I have to use 4mm screws. Modifying an outrunner x-mount has also crossed my mind for building another 2mm.

Thanks again for all the priceless info, you Gandalv of Darkside Strykers

moparmyway

I was wondering why my NEU 1115's (and someone elses that I know) would take an M3 screw (by hand) and everyone else says M2.5
I also have the "H" version with a 5mm shaft, so thats an added wrench to the gears.
Mine came with the addendum as well that said to use M3 screws in the 1112 and 1115 series motors

You should allways add a flat washer to the screw before you screw it down, that will allow about 1/2 to 1 thread of the screw to extend past the plate, and it will not touch the wires.

How did you measure the end of the NEU motor ?
Does your motor have caps on both ends, or is it just 1 end cap and the shaft side is part of the can ?

All of my NEU's have ONE end cap, the shaft side is part of the can, and measures about 3.5mm thick, but again, I have the "H" version (helicopter)

Gryphon

Arcteryxxx,

Error on side of caution and run (2) washers.


When I got my first custom motor from MEGA, I started with KV test (no prop).

Eagle tree with cleared buffer was attached...remember no prop so I could divide RPM by voltage under load.


I raised the throttle and 1 second later smoke poured out of my new motor that I waited several extra months for.........I was devastated for a short while.

I downloaded the data from Eagle tree logger and it showed 60A went through motor and burned it......


*****Problem: I was too excited to realize that I had installed too long screws. The evidence was undeniable....I shipped it back to MEGA and had it fixed. It now handles 140A in air....sure helps not shorting wires with too long screws huh?

No matter what we know, when it comes down to it; we can all screw up.........LIKE ME [&o]



p.s. Good thing I had bought (2) of those.
I called Mopar immediately and he was like: NO WAY, Oh man....
Hearing his voice made me feel better. [sm=thumbup.gif]

Gryphon