Mugi Evo Plans - Evo Plans

The plans and dimensions below are the for the Mugi Evo - optimised for electric flight with speed 400 class motors. When built with our 330gsm material, the Mugi Evo will have a target flying weight of around 450g (with nicads and standard brushed motor).

Twinwall parts list

Cut out the following twinwall parts for your Mugi Evo:

Main wing x 1 Exo-Doubler x 1
Nose doubler x 1   Fin x 2
Elevons x 2   Spine-piece x 1
        Underbelly x 1
Key to the plans and dimensions
This symbol shows the direction of the twinwall flutes on the sheet, in this case, horizontal.
A faint dotted line shows a construction guide-line. These lines are helpful during building and so should be drawn lightly onto the twinwall sheet.
A dashed line indicates a 'score fold' see the tutorials for details. The "TS" icon stands for "this side" - indicating that the score should be performed looking at this side of the sheet.
Main wing dimensions - cut one

Cut a rectangle 800x400mm. You can trim closely along a flute wall and then use this as your baseline and reference for the rest of the dimensions. It is important to make sure that the corners of your rectangle are right angles, so please use a set square to ensure accuracy.

Mark the centre of your sheet at the nose and tail and mark in the centreline.
Now, for each side of your wing, lightly draw construction guidelines from the nose to points 200mm (one quarter span) from each corner as shown. These lines illustrate the path of the pushrod and assist in lining up control runs.

Cut the pushrod exit slot 8mm wide with dimensions as shown. It should be cut on the wingtip side of the construction guideline for correct alignment with the pushrod and servo.


Plan for the Mugi

Nose doubler dimensions - cut one

The purpose of the nose doubler is to add essential rigidity to the floor of the Mugi's nose. Although it's mounted at 45 degrees, corner forwards, when you cut the doubler the flutes may run across the doubler parallel to its side, as shown. The doubler is a diamond shape as opposed to a triangle to avoid creating a strongly defined edge which would buckle upon impact.


Elevon dimensions - cut two

Cut two elevons to these dimensions. Although they might seem large, with reflex (slight up-elevator at neutral) applied, they are an essential area of the wing. For first flights the control movement can be reduced but when you're confident in the abilities of your Mugi and yourself then those large elevons will grant you amazing agility.


Exo-doubler dimensions - cut one

The exo-doubler is a very useful and simple way to extend the life span of your Mugi. Since it's the nose that usually takes the brunt of impacts that's where the reinforcement is best employed.
Start with a 100x200mm rectangle with the flutes running in the short direction. Now score fold from the nose down the centre and to the two corners as shown by the dashed line, and then cut the corners off your doubler.


Fin dimensions - cut two

The fin below is cut with the flutes running vertically for strength and ease of mounting. We'll be using short dowels to fix the fins to the Mugi and these will go into the flutes. You can use a piece of tape wrapped around the leading to clean up the aerodynamics of the open flutes.


Spine-piece dimensions - cut one

The spine-piece will sit across the join on the top of the Evo wing and contains an integral access hatch that will allow easy access to the radio components and flights batteries in your Mugi Evo.

The flute direction is spanwise so as to provide the strongest resistance to any compression forces that might try to 'fold' the wing in flight. Note: in practise you will need to trim this piece to fit the dimension from the exo-doubler to the tail of your aircraft, which may vary slightly from airframe to airframe. Therefore, the dimensions marked ~ should be taken as nominal measurements and are variable to fit your airframe.

The dotted lines on the plan below are the hinge lines of the access hatch. These dotted lines should either be score folded or cross-flute cut to create a useful hinging mechanism. The solid black lines forming an inverted 'T' shape on the plan below should be cut - creating the two doors of the hatch.


Underbelly dimensions - cut one

The underbelly reinforcement sits down the centre of the underside of the Evo wing. The flutes will run perpendicular to the bottom surface of the wing and so give a cross-ply effect of adding resultant stiffness in both directions. This piece will help to prevent the airframe from compressing tail-to-nose in a hard nosefirst impact. With the added weight of a motor on the rear end of the aircraft, this piece is especially useful for electric Evos.
Note: in practise you will need to trim this piece to fit the dimension from the exo-doubler to the tail of your aircraft, which may vary slightly from airframe to airframe.



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