RE: Comp ARF Flash update
 

MC3854,

Good thought, i had forgotten about those servos. I have no problems using those, i just don't care for the slop in the MG 8411. I was looking through Horizon website for a different servo but hadn't decided on anything. The only bad thing is the 8411SA is out of stock until late october it says. Thanks for the suggestion. By the way, did you get the PM i sent you?

RE: Comp ARF Flash update
 

Sean, I know what you mean about the 8411's with the loose gears but having used them in a lot of different jets to date I can honestly say that I have never noticed that it has any adverse affect in the air when flying the plane.
Plastic gear servos would probably be fine but you do have to worry about bumping the surface and stripping a gear that might not be noticed until it is too late. For me the trade-off of a slightly loose gear train (that I can't even notice in flight) is the better choice but I know everyone has their own opinion of what they prefer.
I think the Hitec metal gear trains are excellent but I have not used their digitals enough to trust them to be put in my jets yet. I know people use them with good success but I just have no experience with them. You might inquire? Gary

RE: Comp ARF Flash update
 

Saddler,

Just dumped some photos on my site as part of a build thread I am going to write up. Take a peek if you like.....

www.composite-arf.co.uk then build threads.

Hope to get a few more pics up soon.

Rgds,
Mark

RE: Comp ARF Flash update
 

Hey guys

Just got all the radio gear into my Flash, went in pretty quickly. But try as I might I cannot get the flap servo's to stop chattering!! They were singing wildly to start with until some end point adjustment was made, but the chatter is always there. I have JR DS8411's on all surfaces. This is my first dealing with an 'all digi' servo jet. I have heard other peoples models do this also, but is it ok for it to do it all the time??

Just the engine to go in next, little jobs after that and we're off!! :)

I'm also having a little trouble mixing the 'brake' part of the valve (Behotec C36) into full elevator down command. Anyone who has a JR 9x and could inform me how to achieve this, I'd greatly appreciate it!

Thanks for any advice.


Chris

RE: Comp ARF Flash update
 

Jr digital servos chatter! It's normal as long as you are sure they are not in a bind! I imagine it is the weight of the flap causing it! Turn it on it's side and see if they quit! That will make you feel better!

RE: Comp ARF Flash update
 

I started my Flash this last weekend, and with one more night on the canopy, the fuselage will be entirely complete. The wings will probably take the better part of a day. That still means I'll have the bird completed in a week, and I am not a particularly fast builder. The kit has gone together very smoothly. If it flies as well as it builds, I will be a very happy guy.

RE: Comp ARF Flash update
 

take the 8311 instead it is the same servo just plastic this way there is no play

RE: Comp ARF Flash update
 

Chris

They should not be very loud!
Are you sure the flap pushrod is clearing the top wing skin/slot? the slot need lengthing from the factory length.

Set up elev-gear on mix 6, put a 50% offset on the stick so the brake only comes on at half down elevator
Pos 0 +what ever you need to get movement, Pos 1 to zero so that the brake does not operate with the gear up
set GER to pos 1

regards

Dave Wilshere

RE: Comp ARF Flash update
 

The JR 8411SA uses a hybrid gear train. The final output gear and shaft are metal with the intermediate gears being nylon. This absorbs a lot of the initial bumps on flight surfaces and allows you to still use a metal servo arm and crank it tight with no ill effects. Some of the newer JR servos are using a new type of resin gear that is supposedly much stronger.
Many people will use a good cored and coreless servo on the flaps of large planes and jets. This way there is not the "buzzing and oscillation" issue if there is slight pressure on the flap servo in either position due to minor linkage adjustments at each end point, which is hard on a digital servo. I know a lot of people that use nylon geared servos as well as metal. JR offers the 2721 with a metal gear train and many jet flyers use this servo for flap applications.
As far as the 8311 goes, JR calls it a helicopter servo. Initially, they did not recommend this servo for aircraft application for some reason. I think it had something to do with the motor in that servo, but have not checked recently.

RE: Comp ARF Flash update
 

Thanks for the info Dave, I didn't even know mix 6 was different!![:o]

I'll fiddle with it this w/e, swamped with work.

Thanks again.

Chris

RE: Comp ARF Flash update
 

Is anyone flying this with a P-70? How does it perform? How do you think it would do off of grass with a P-70?


Thanks,

DK

RE: Comp ARF Flash update
 

. I know Ray Labonte is flying his new Flash with a P-70, he says it flies really good and keeps the plane light, only needs one fuel tank also. He was going to have it at Superman Jets. It has a really cool airbrushed paint scheme. I am still considering the Artes Falcon for mine, I will be flying off of grass most of the time, and I think the P-120 is overkill, and want to keep mine light and still have good performance from grass. Jack

RE: Comp ARF Flash update
 

Hi Guys

I'm currently building a Flash with a Jetcat P80. I have a couple of questions for any builders who are using this engine. If I follow Jetcat's recommended distance for the front of tailpipe to rear of exhaust cone on the motor (20mm) then I'll have to move the engine back on the mounting rails, almost to the rearmost position. If I do this, it will upset the fitting of the bypass and may alter the cg. Has anyone else encountered this and is it a problem or not? If I mount the engine in the forward position, it appears to be a long way forward of the tailpipe and may cause problems with the carbon bellmouth. Is this an issue or not?

Also, I've had to taper the mounting packers to achieve a correct alignment of the engine to the tailpipe, has anyone else seen this problem?

Any comments would be welcome.

Cheers

Rod

RE: Comp ARF Flash update
 

i have been looking on the website for the manual for the Flash, but cannot seem to locate it.

any help would be appreciated.

Cheers

Joe

www.warbirdpropdrives.com

RE: Comp ARF Flash update
 

Try this link

http://www.composite-arf.com/arf/ima....manual.v1.pdf

RE: Comp ARF Flash update
 

thanks Geoff...works fine..

off to do some reading...so many motor and gear choices..

cheers

joe

www.warbirdpropdrives.com

RE: Comp ARF Flash update
 

Guys,

I'm working on the rudder servo installation for my Flash. The problem I have is if I put a servo into the pre-mounted servo plate in the vertical stab, the servo arm lines up right at the base of the stab. Its nowhere *near* the 1 5/16" up from the base that Dave suggests and not anywhere near in line with the two arms already mounted in the rudder. Is my servo mounting plate that far off?!?


Also, did you guys use a Matchbox on the flaps? Also how about the elevators?

Thanks!
Bob

RE: Comp ARF Flash update
 

Make sure you are mounting the servo upside down in the mount just like it states in the directions. The servo arm actually has to go through the mount and then you put the servo screws in from the bottom of the servo. Basically just backwards to what you would normally do. I took a straight edge and drew two lines based off of the already installed rudder horns. I shined a bright light from the back side of the fin and my servo arm hole ended up being exactly in the middle of the two lines i had drawn from the rudder horns. The servo and rudder horns lined up perfect in mine! I would suggest making sure that you understand EXACTLY what the directions are saying and you will probably find that it lines up as advertised! That was my experience anyway...

RE: Comp ARF Flash update
 

Bob

Hopefully you now have the rudder servo sorted

I used a match box on flaps only.
elevator I use dual elev on JR (3 & 8)

Regards

Dave

RE: Comp ARF Flash update
 

Ah, *that's* what they meant by "mounting inverted!" I was thinking they were talking about it hanging in the straps during normal flight... :D Glad I waited and asked the question.

Duh - my only excuse is it was a late night last night and I'm a bit under the weather... I used the guidance from above and Dave's earlier measurements and it fits perfectly. Thanks Saddler and Dave for the replys! Time to order a Matchbox and press forward...

Bob

RE: Comp ARF Flash update
 

You guys are lucky, you have your Flashes. Been waiting since mid September for mine.


Regards

Jim

RE: Comp ARF Flash update
 

i had 8 hours (45 flights) on ours ,i just sold it.
i think i was ready for a bandit ;).
now i call the flash "a poor mans bandit";)
anyway have fun with it , it was for me a very good flyer and extremely strong.
i did 180 degree turns on a dime , and at full throttle.
Ali did snap rolls with it , that i never seen in my life..
good machine....
ps: keep it light!

RE: Comp ARF Flash update
 

Jim,

Yea, my wait was a couple of months too, I think. Hopefully it will be here soon. Obviously I haven't flown mine yet, but as far as the kit is concerned, it was worth the wait...

Bob

RE: Comp ARF Flash update
 

Or you could call it a Smart Mans Bandit, being half the price it sounds like it does the same kind of stuff as the more expensive one.. I will know soon enough, I have one coming, looking forward to it!

RE: Comp ARF Flash update
 

true , by the time it hits europe they are 3 times a flash.....
[:o]