RCU Forums

RCU Forums (http://www.rcuniverse.com/forum/)
-   Park Flyers & Backyard Flyers (http://www.rcuniverse.com/forum/park-flyers-backyard-flyers-148/)
-   -   Parkzone Releases New F27 Stryker Model! (http://www.rcuniverse.com/forum/park-flyers-backyard-flyers-148/3323165-parkzone-releases-new-f27-stryker-model.html)

critterhunter 09-02-2005 11:38 AM

Parkzone Releases New F27 Stryker Model!
Was just at the local hobby store when UPS brought in a new shipment of F27s. Looks like Parkzone is really doing thier homework. It's the same price as the old model and among other things features...

Generation 3 Body AND hinges already installed on the flaps!
Nimh and 3 cell lipo compatible RX AND comes with standard prop and a lipo prop!
The canopy AND grey cover are now vented!
The paint job appears much better quality.
May be other updates but I didn't look over it too long.

I'm glad to see they are doing improvements to this bird and are not just happy with what it originaly had. Now, if they'd only come out with some kind of brushless adapter that would hitch up to the stock speed control they'd have really tweaked it out.

AeroCat 09-02-2005 12:11 PM

RE: Parkzone Releases New F27 Stryker Model!
Cool! What size and pitch was the Lipo prop?.........nevermind, it's a 5x3

I wonder if the new Rx is from the P51?...and it is the same Rx/ESC

dribbe 09-02-2005 01:03 PM

RE: Parkzone Releases New F27 Stryker Model!
The cat's out of the Bag now!

(We also turned loose another significant item!) [X(]

Another change to the F-27B Stryker is the mixing ratio. It has a faster roll rate.... It can now roll very fast, while still having reasonable elevator throws.... be ready to get more use from the mode change switch!

Best after market batteries are Thunder Power or E-Flite 2100 3s. Fit right in.

I must say, the Stryker flies better than ever!


sjchmura 09-02-2005 04:14 PM

RE: Parkzone Releases New F27 Stryker Model!
SO did the motor change also or the same 480? What prop is the new "Lipo" prop - a 6x4???

AeroCat 09-02-2005 06:00 PM

RE: Parkzone Releases New F27 Stryker Model!
The prop is a 5x3. It's listed under the Stryker Parts on www.horizonhobby.com .

sjchmura 09-03-2005 12:16 AM

RE: Parkzone Releases New F27 Stryker Model!
So why a smaller prop (length) and less pitch?

Glacier Girl 09-03-2005 04:58 AM

RE: Parkzone Releases New F27 Stryker Model!
Smaller prop for less load on the motor. So motor drawls less amps. May increase life of motor somewhat. But if memory is correct, it's still a 6 volt motor, life will be limited on 11.1 volts.;)

sjchmura 09-03-2005 09:06 AM

RE: Parkzone Releases New F27 Stryker Model!
That could be why my "cheap" stryker on 9-cells flies well with the Aerobird Prop and does not heat up to much. THis is about a 5.5x3 prop.

On the lipo it works great.

Have you seen anyone try the $12 Permax 480? Looks same size as the Parkzone. Thus a $42 upgrade guide could be in order :)

dribbe 09-03-2005 11:00 AM

RE: Parkzone Releases New F27 Stryker Model!

To answer the issues above....

In short, the LiPo prop is the 'correct' load for the Stryker motor operating on 3s LiPo batteries.
-It lets the motor rev higher on the higher voltage as it should for the optimum blend of power and efficiency.
-This puts the correct amount of Watts through the systems for good motor and ESC life.
-The pitch and diameter are selected for a great combination of speed and power. I can do an immelman after just accelerating for a couple of seconds after launch.
-Good run time. (without fade due to abuse)
-Good partial throttle efficiency.

If you over prop and LUG the motor, you may get a little more power in the short term, at the cost of motor damage, esc damage, battery abuse, and short run times and fading power.

We put a lot of engineering time, and testing and CNC prototypes into this prop. I think many of you will appreciate it.

GG, despite 'marketing' points, brushed motors don't really have a 'voltage' such as 6v. Motors have a 'practical range' such as 5-9 volts. Oversimplified, it is not the particular (practical) voltage that hurts a motor. Motors generally have an amount of 'wattage' they can continuously deliver. Wattage is the volts times the amps... Motors are hurt if you load them too much, and try to input too many watts.

Most quality 480 can motors can take an input of perhaps 130-140 watts.... so if the LiPo is 10v under load, you can handle about 13-14 amps assuming decent cooling. (the more effeciently it is coupled to the prop (linked to operating the motor at an optimized RPM), the more power OUTPUT you will get!)
-Power Out is approximately Power In times Efficiency

Also bear in mind that the motors practical voltage/rpm range is set by the 'windings'. Windings are a combination of wire diameter, and number of turns. There are THOUSANDS of combinations of windings, further varied by MANY magnet, bearing, shim, insulation types, etc. Speculation about motors is an exercise in futility. The only way to KNOW what it is is to test, and dissassemlbe the motor!

The Stryker's motor has a practical voltage range of 6-11 volts.... for GOOD power, lets say 8-11 volts. It is not a 6V motor, and PKZ would never market a motor in this fashion. IMHO, this is a poor way to describe a motor. (The lowest nominal voltage we have ever paired it with is 8.4 (7 cells).

Hope this helps add some understanding.

Have Fun,

AeroCat 09-03-2005 12:04 PM

RE: Parkzone Releases New F27 Stryker Model!

Being new that helps out alot, thanks!

One other question, the 480 motor is still the same as previous Strykers, correct? And is the new cooling element on the motor crucial if running Lipos? I'm building one right now, so I'm buying parts. Is this part sold separately with/without the mounting hardware?


dribbe 09-03-2005 01:05 PM

RE: Parkzone Releases New F27 Stryker Model!
Hi Aerocat,

There was a running change to the Stryker at some time during its "A" life. The motor with the metal 'flux ring' was used.... It is pretty much the same motor, but the flux ring makes it more efficient, so you get more power with less heat.... The difference is not huge...

The B motor is the same as a late A motor, which is a little better than a early A motor. All same nominal voltage range.


AeroCat 09-03-2005 01:23 PM

RE: Parkzone Releases New F27 Stryker Model!
Is the flux ring just a thin strip of metal wrapped around the can?

Will520 09-03-2005 02:36 PM

RE: Parkzone Releases New F27 Stryker Model!
This is Flyingace451 on his friends comp:

THANK YOU PARKZONE!!!! They were just in time...I am gonna get that plane for Xmas.:D

redgiki 09-03-2005 08:06 PM

RE: Parkzone Releases New F27 Stryker Model!
I just bought one of these today. As the weather report is showing planned 10-15mph sustained winds for the next 3 days, I do not expect to fly it yet. The plane seems pretty solid. Out of the box, the only thing I had to do was attach the nose, using the decals if I wished, and put on the vertical stabilizers. The stabilizers do not seem to come with the "double-sided tape" mentioned in the manual, but the fit is very, very snug. Hope they don't come off during flight. Should I secure them with a touch of foam-safe CA?

I yanked the motor out to do a water break-in, as this procedure seemed to improve the longevity of the 370 motor in my J-3 Cub. I've enjoyed the heck out of my cub, and made sure the Stryker was on channel 4 as well so I only have to take one radio (the new Stryker one) with me to the field when I fly. After break-in, I oiled the bushing with sewing machine oil, and the motor seemed strong with the stock battery. There was a LOT more wind behind it than I'm accustomed to on my J-3!

My only concern is the throws. It seems as if a left roll has way, way less of a throw than a right roll. When I push the stick to the right, the ailerons <b>really</b> crank hard to the right. Whereas to the left, they move very little. I haven't measured the amount of throw, but it's a substantial difference. Is this because the torque of the motor makes a left roll more responsive than a right roll anyway?

The only other problem I noticed is that I got a second battery pack, and the servos seemed "twitchy" when using it. The same battery pack, however, doesn't seem to hold a charge well, so I'll be returning it to my LHS.

I'm recharging the pack now to do bench duration tests so that I know how long I should plan on flying wide-open and at half throttle with this puppy. I'm really excited!

I have a Futaba 6exa transmitter waiting on my bench for the day I replace the stock electronics with a GWS micro set and hit the "dark side". However, I expect to get a lot of fun out of this unit with the stock stuff until then!

Overall, it feels like a pretty solid airplane. I have a little problem with the wing decals trying to peel off, and some of the paint seems to have rubbed off near the nose during shipping. I'm looking forward to many happy landings.

I think I should have purchased a spare prop, though. About one in ten landings on my J-3, I came in a little hard and tended to do bad things to it...

dribbe 09-03-2005 08:29 PM

RE: Parkzone Releases New F27 Stryker Model!
Center your Tx trims, then make sure the surfaces are level (no right or left). The throw should be pretty even.
(You will likely want LOW rate... The ailerons are quite responsive on the Stryker B. Low time pilots may even mechanically reduce their throws if it suits there taste.

There is a servo motor on each elevon, so each one contributes to left and right roll.

I would launch with some UP trim... give you more time to get to the controls as you pick up speed.

I wouldn't worry about a little servo jitter.

I would say... expect 7-8 minutes wide open... 10-12 at reduced power.

Yes, the flux ring is a then metal sheet wrapped around the can.

Have Fun,

redgiki 09-04-2005 01:13 AM

RE: Parkzone Releases New F27 Stryker Model!
Thanks for the tips! After repeatedly wrecking my Parkzone J-3 cub, I finally got some help from more experienced flyers, and feel confident. But not confident enough to maiden my Stryker on my own :) I've got a date for the first still morning with my neighbor, who has been flying for fifteen years and specializes in really freaking fast models. I suspect a stock Stryker will be a walk in the park.

By default, on the Stryker-B, the clevis are attached to the outermost pin on the control horn, giving the least amount of throw. Should I leave this as-is for the maiden, or go up a hole or two?

sjchmura 09-04-2005 02:21 AM

RE: Parkzone Releases New F27 Stryker Model!
Has anyone seen these new props yet? How will I know if my motor is "dying" - is it a quick death (like Korean gun camera footage) or a slow death?

Also is the P51 motor the "new one". I have a recovered P51 one also (same plane I got the electronics from for my lipo stock conversion :)

sjchmura 09-04-2005 02:25 AM

RE: Parkzone Releases New F27 Stryker Model!

THanks for all your explanations. SO what pitch prop am i running now (aerobird challenger). It seems to be about 15cm in length - less pitch then the stock prop just about 1 cm longer.

It flies better on this then the "6-cell prop" F27

Is the new Lipo prop the same as the old F27 "6-cell" prop?

critterhunter 09-04-2005 11:51 AM

RE: Parkzone Releases New F27 Stryker Model!
Hey Dribbe, can you tell me what size and pitch prop the Challenger and Extreme uses? I would like to put an electric carbon fiber prop on both of them for less flex. The Extreme prop tends to make a ripping noise when I pull hard Gs with a 7 cell pack.

On the Stryker mods...DO NOT glue the verticle fins in! This will cause them to chunk the foam in a bad crash. You want them to seperate in a bad crash. Same with the nose. Keep it snug but loose. Some double sided tape at the tip of the fins is best to hold them. Just a little. For the nose, the tape won't last long. I'd put a doll rod in the front chamber crosswise snug with some CA. Then, drill a little hold through the front nose mounting area. Take a toothpick and stick it in the nose "knobs" from top to bottom and use this to attach a rubberband to it and the doll rod in the nose. Use a WEAK rubberband as too strong and it will chunk foam. You want the nose to move when it needs to. For the canopy and battery hatch. Glue them together and put two doll or carbon rods across them underneath for more strength with glue. Use the back hatch clip until it breaks (it will), then use two small magnets back there and glue metal to the underside of the hatch. Or, use another doll rod and rubberband. For the front canopy area I glued a Challenger canaopy latch that the rubberband hitched to under it. Then use a rubberband to hitch it up to the front doll rod used to hold the nose. Glue velcro into the battery area and use this to wrap over the battery to hold it snug when in place. If you don't the battery will come out in a crash and take the canopy and maybe the RX with it. I'd also convert the battery plug to Deans. To many close calls for me. You can also reverse time the motor for more power. I did this to my stock Stryker and it works great. Bend back the tabs holding the back motor plate to the casing. Notice on the right side there are two metal tabs over a piece of plastic. Rotate the plate clockwise so the bottom tab now rests in the little plastic notch that the top metal tab did originaly. Finally, pick up a $2 400 motor heat sink. It's aluminum and will just snap over the motor and keep her nice and cool. You might also want to use strapping tape in the back area, top and bottom, where the motor mount area is. Bring the tape forward a good five or six inches on both sides. This will prevent the motor from chunking the body. Take off the motor mount to do it and then mount in on the tape. I go as wide as the verticle fin area on both sides. This is one of the weak points on the plane.

redgiki 09-04-2005 02:16 PM

RE: Parkzone Releases New F27 Stryker Model!
Thanks for the tips. Two more days of windstorm in the forecast, so more time in my workshop and on the FMS sim for me. I will do the mods you mentioned, as what I've noticed is that on my J-3, a little preventative "repairs" prevent the worst damage later. For instance, I broke the front of the fuselage twice before I learned the trick of spraying a little expanding foam in there. Add a penny near the tail to counterbalance the weight, and it flies GREAT and handles nose-overs without creasing anything. Before, it would crack the internal skeleton of the fuselage every time, requiring a few hours of repair in my workshop. All for a weak nose-over that shouldn't have hurt the darn thing.

I definitely appreciate the tips! An ounce of prevention, and all that!


sjchmura 09-04-2005 09:32 PM

RE: Parkzone Releases New F27 Stryker Model!
How do I get the stock motor OUT of the mount? I have a P51 "B" motor (I have an original A one) and thought I could just take off the 2 screws and snap it out - well - not so.

Do I need to take the whole motor mount off the plane?
ALso how do I "Reverse TIME" the motor?

jdix42 09-04-2005 11:51 PM

RE: Parkzone Releases New F27 Stryker Model!
hey peeps first of all im new to this group and i want to say thanks for all the advice ive already read on rc universe this is really great.
the f27 is my first plane ever and ive been flying for about 3weeks now and its going great i did have a little sim experience with realflight g2 which i do think helped

im trying to find out now if anybody has used battery packs from battery space they have great prices and the stock charger doesnt seem to be that great

also i would like a little more power and speed without spending much money any suggestions?

thanks i really enjoy this forum and the styker just rocks!!!!


keepawiki 09-05-2005 12:12 AM

RE: Parkzone Releases New F27 Stryker Model!
[quick question to southern hemisphere pilots]

Any Aussies, NZ'ers trying to get an F27B? I'm having trouble finding a stockist/importer. I contacted modelflight.com.au in SA who supply to alot of LHS and they said it would be a long time coming. Or any comments, recommendations, (donations even?) from Aussies, NZ'ers who have had success ordering direct from the manufacturer in the US?

[please continue rest-o-worlders]

drunkenbushman 09-05-2005 06:40 AM

RE: Parkzone Releases New F27 Stryker Model!

ORIGINAL: keepawiki

[quick question to southern hemisphere pilots]

Any Aussies, NZ'ers trying to get an F27B? I'm having trouble finding a stockist/importer. I contacted modelflight.com.au in SA who supply to alot of LHS and they said it would be a long time coming. Or any comments, recommendations, (donations even?) from Aussies, NZ'ers who have had success ordering direct from the manufacturer in the US?

[please continue rest-o-worlders]
Just hop up a stock stryker, thats what im going to try an do, but it seems like a very daunting task the more i read, im sure ill eventually get it working :P

sjchmura 09-05-2005 07:24 AM

RE: Parkzone Releases New F27 Stryker Model!

Get the "6-cell" prop F27 and a 9-cell CBP750AA (cheapbatterypacks.com).

It Weighs 4.5oz (less then the 900mA but poor discharge rate stock cells) and has Lipo like performace for a good 5 minutes.

See my "$31 upgrade guide"

The only way to really get great performace is if you can swap out the rx/esc with one from the p51 and buy a Dymond Lipo. So for $35 the lipo is great but you NEED the Lipo compat esc/rx from a p51 - else if you fly too long the lipo will blow up :)

All times are GMT -8. The time now is 05:50 AM.