That boy has potential

I like the motor, would we have to up our ESC's? is matching motor (peak 25A) and ESC (also 25A)  amperage okay or would we start seeing parts burnout? maybe mark B could weigh in?

Assassin Wing Build Issues:

1)      FC-2812 motor – The set screws fell out.    Added Locktite to the threads.

2)      Elevon horn - The elevon horn detached from the wing in a minor crash.    I re-glued and taped over the horn on the bottom of the elevon. 

3)      Elevons – Elevons will not move to lowest defection.  Allow a large enough gap when taping the top of the elevons so the bottom tape and covering does not bind the elevons.

4)      CG – The CG is behind the spar.   The CG is moved aft with the addition of the winglets.   The winglets move the center if aerodynamic pressure aft too.    My wing is stable with the CG about 2 mm behind the spar.  

5)      Push Rods – The push rods bind when the servos are mounted horizontally flush with the wing surface.     An alternate approach is to vertical mount the servos.   Putting the Dubro EZ-connectors on the servo arms instead of the elevon horns raises the push rods enough so that the servo arms can be below the wing surface. 

6)      Weight – Adding the winglets and not removing the outboard leading edges will result in a wing that weighs 16.2 oz. without the battery and 20.8 oz. with a 1500 20C battery.   Some weight can be saved by using 1” tape on the leading edge and reducing covering overlap at the joints but the path to 17 oz. AUW is not at all clear.  

7)      Winglets –My first design used light weight plywood.  These fractured on the first crash.  My latest design uses relatively stiff plastic from a three wing binder found at Staples and are taped on.  These seem relatively indestructible.

8)      Prop saver – To be effective the prop saver must be mounted at the end of the prop shaft.    This moves the props aft and puts undue stress on the motor bearings.  Also, the screws cannot be tightened enough to prevent it from rotating on the shaft.      The prop shaft  was cut to a minimum length and flats filed to enhance the effectiveness of the set screws.

9)      Push rod supports – The straws constraining the push rods split.    Supports can be constructed from the same binder material as the winglets.   These are hot glued into the wing.

10)   Prop – The prop does not fit on the prop saver.  The prop washer can be glued into the prop.

11)   Expo- 25% on aileron and 15% on elevator seems OK for me.

12)   FC-2812 – the motor speeds up slowly so launcher starts will be a problem.  No problem with a hand launch however.

13)   Elevon deflection – The wing rolls are not axial unless the down elevon deflection is greater than the up elevon deflection.   Here are my current deflections with the “wheel” servo arm on the HS-82MG servo with 5/8” horn height on the elevon:

Half Up: ½”; Full up: ¾”; Half down: ¾”; Full down: 1”

I achieved this by programming 150% down travel in the DX7.   Since the differential is opposite of normal aileron differential, I could not use the built-in capability in the DX7.   In the future I would probably use a longer servo arm and mechanical differential as suggested in the build instructions (angle the servo arm toward the bow) and then reduce the amount if necessary using the built in function.   I would also do this with a less flexible transmitter.

Its really hard to be "too late" John F. didn't fly in the first 5 races and still took second place last year! If there is enough interest (and seeing there is already 3+ people) that want to order, group ordering is definitely the way to go. 

It should total around $100 for the plane plus the motor / esc / servos. If you have a radio and reciever already anything will do in these guys. Some people last year pulled their 72mhz transmitter/recievers out of retirement since they were lying around. If you dont have one (and dont want to make the investment yet) you can go with the a Hobby King 6 channel radio  http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=15140 (need the 6 chan for the mixing abilities, also you need the programming cable) or the 7ch http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=10173 (dont think you need the pc cable which should land the total package around $150ish 

Last year's competition was a ton of fun, hopefully we hear more about this at the March Meeting (Hint hint... berardo / tony caugh caugh)

I don't think we need to make it that complicated.  We are still checking a few motors out, and will know is plenty of time for folks to purchase.  Last years motor was not as durable as we would have liked.  I think going to a 7x4 from a 7x6 would have made it last fine, but would have slowed the wing down quite a bit.

Plans for the new motor:

Similar weight to last year, so no big effects on CG.

Use same ESC, (25A), since we all have one.

Use same batteries, since we all have them, and really they are the max for the wing.

Use same prop if possible, not a deal breaker, but if possible.....

Keep current load to insure safe motor, ESC and battery, this is number 1

Not increase the speed of the wing too much, so flying can be safe and construction can be similar.

Tony may have more information/ideas.

Yes, Glue the 2 wing peices together, then use the sprey glue, then cover with the laminate, after the carbon spar is installed of course.

the tape will still yellow from the sun