Hi,
I would be thankfull if someone can help me with the following:

1) I just can't get the Flap servos properly alligned to work with no tention....(I have chosen the method where the servos are in side the fuse on the SM page) Any tips?

2)This is my first inside istalation of a turbine and am trying to figure out wether the aluminum bell mouth which is loose, is to be used or not(in the bypass) and what clearance between nozzle and pipe ?


Thanks in advance

Eray Savci

Please...

1 - I would suggest that you do not use the method for the plug-in flaps. The type of wing spars used by Skymaster allows too much play when the wing is inserted each time before flight and the wing will likely not align in the same position every time when you install them. This can cause problems with binding the servos and may result in a failure of the servo.

If you simply mount the servos in the wing as is discussed in the second option in the manual you will eliminate the problem altogether. BVM uses plug-in wings on their T-33 for flaps but it is a round wing tube that is very accurate each time the wing is inserted. There is an F-18 build thread here on RC Universe that shows the installation of the flap servos into the wings.


2- If you are using a bypass then it should have a pipe that fits around the back of the bypass and two straps that are bolted to the rear of the bypass. If I am not mistaken the bell mouth was intended for use w/o the bypass.

Gary

Eraysa -

I have posted pics and dimensions for both the flap servo (in wing) mounting and pipe bellmouth to turbine clearance, as well as the pipe mounting, in the SM F-18 build thread [link=http://www.rcuniverse.com/forum/m_2039546/anchors_2039546/mpage_1/key_f%252D18%252Cbuild%252Cthread/anchor/tm.htm#2039546]here[/link].

Check out Posts #3, 16, 65, and 66, they should help you out.

Barry

Barry,

Thank you for the post. I was going to refer the Eray to your previous F-18 building thread too.


Eray,

Barry's building threads do have great reference material for you. If you decide to use the method from Skymaster's menu, make sure your hinge is strong enough for the flap. Most of the time the play is caused because the hinge is too soft. For the pipe, you can choose a bellmouth or bypass. This is actually a personal preference and both setups work just fine.
You should keep a 10mm clearance between nozzle and pipe.

Thank you very much for your replies...

Rgds

Eray Savci

I also install the FLAP SERVO inside. I had to do some adjustment to prevent the servo from binding. Is there anybody using this setup??

I actually had mine installed inside and fine tuned, but there was way too much slop in the control throw. I ended up using Barry's measures and all worked out well. The only thing I would suggest is to reinforce the spar to wing skin joints with aeropoxy once the hole is cut and I might lay some carbon fiber cloth down next time to strengthen the wing skin where the servo attaches.