ORIGINAL: Sandmann_AU
Good on you Matt.. the DA's probably the best of the cheaper civilian twin ARFs out there, unless you want to spend big bucks on one of those twin Cessnas with the lighting kits. Chances are this one'll be the updated one with the washers glued in place etc. Recommendations for improvements:
- Use a pull-pull rudder system to avoid the long rudder pushrod
- get a fults dual strut nosewheel
- 2 1/2'' dubro wheels for mains and a 2'' for the nose to replace the foamies it comes with... makes it roll easier
- dump the little 6oz tanks it comes with and get those larger flexible tanks (10oz sullivan I think? Go back through the thread to find them)
- put an on board glow in to lessen the chance of a single engine flame-out at low revs.
- use a little vaseline on the hinge pins when fitting them to ensure you don't get epoxy in the hinges. I prefer the robart point hinges but the pinned ones are fine too, and fit in better with the pre-cut CA hinge design. To reduce the gap recess the pin area into the moving surface, not the fixed one.
- If you're sealing the gap with *kote you can do it top or bottom. Top looks better when it's on the ground and you won't see it when it's flying. You can even do both top and bottom if you want to. Flex the surface downwards fully then apply it to the top... reverse it for the bottom.
- If possible use two channels for throttles with computer mixing so you can have one trim for both throttles, and a second trim for just one (easier to balance engines). You can also throw in some throttle steering by mixing the rudder with the throttles. If you do this one, assign a switch so you can disable it if you don't like it.
Mine has a pair of super tigre 40's and I needed to mount the main battery and on-board glow battery in the nose (along with an engine mount and small aluminium plate) to get it balanced at 105mm.
Thanks for the input.
in DA #1 I used the included rudder pushrod, I will adjust to either a stiffer rod for #2 or pull pull as you suggested
DA #1 had Dubro 2.5 wheels all around, and I used a Dual strut nose wheel that I had from an old cessna kit. not sure what make it was, but I liked it.
I found the included tanks had enough fuel for a comfortale 9 minute flight and were still 1/2 full on landing, so I don;t think I need bigger tanks for the flying I do. (unless there is another reason I should change the tanks besides increased fuel capacity) I did change the tank stoppers on DA #1 to Sullivan stoppers
I had, an onboard glow system on DA #1, and will reuse on #2. 4000mah nicad. never failed me so I will re-use
I will buy some of these pinned hinges you suggest. for #2
I will seal top and bottom of ailrons with monokote as per your suggestion
Already did use 2 channels for throttle. low end RPM was 2050 and 2047 at idle, and high end was 13500 and 13475 at mid stick they both settled in at 7500 and 7650. I adjusted the end points on the servos with the computer radio to get these numbers and it seemed to work well, although I noticed that Engine #2 would spool up a little slower than #1 which caused a slight yaw left on throttle up. I might need to see if I can throttle delay #1 to compensate. I will experiment. Might be fun to try throttle stearing too, on a switch like you suggested.
I did not add a 2nd trim for the throttles, I just trimmed each individually using end points. not sure how to add a 2nd trim. I have the Futaba 9CAP if anyone has ideas on how to do that let
me know.
I will reuse my Thunder tiger .46 engines in #2. I had mine balanceed with my Onboard glow battery in the nose, and my 6V reciever battery ziptied to the 2nd bulkhead back from the nose, and it balanced somewhere etween 105 and 110mm I don;t use a balance stand I just use my fingers so it is a ballpark CG.