squaring the engine
 

It's my first glo kit (midwest aero-star 30) and the instructions are not very good in describing the best way to make sure your engine is square in the mounting bracket. What have you found is the best way to do this?

squaring the engine
 

Mount motor in plane with prop attached.

Turn prop until blades horizontal

Measure from blade tip to wing leading edge on both sides. Should be equal :).

Some tips and explanations.

Use 2 setsquares, one at prop the other at l/e and measure between the verticals.

If the plans require sidethrust (not common on rc models, but...) calculate the difference between the two measurements at prop tip (it will probably be a matter of millimeters...

Make sure that you have some means of getting the wing into exactly the same position easily every time you assemble, including at the field. It only requires 4 small balsa (1/16 sq is good) "keys" glued to the wing so that they sit snug against the fuse when everything is in the right place... :):) Same with the stab if it is not glued on...

squaring the engine
 

Higley's book on mounting has great instructions on how to do this and more with plenty of pics. I have benefitted from them a lot !

squaring the engine
 

Thanks, it sounds like a good plan

squaring the engine
 

If your fuselage is straight then the centerline (looking down on the plane) is straight, and hopefully your rudder is mounted straight then you can place a piece of masking tape across the top of the fuselage back by the rudder and across the centerline.

On that masking tape draw a 'dot' or 'cross mark' on the centerline.

Place a straight piece of wood on the engine as if it were a prop. The wood can be any length that is about the size of a prop and should be straight and stiff (like plywood) and the same length on each side of the propeller shaft or you can just mount a good quality prop that does not have bent tips on the engine.

Place the engine in the mount and take a 'thread' that will not stretch (thick) or 'dental floss' and place one end on the mark you drew on the masking tape (you could tightly tape this in place right over the mark). Then extend this 'thread' to the tip of one end of the plywood or prop blade on the 'left' side of the plane. This distance should be exactly the same distance as the distance from the same mark on the masking tape to the end of the plywood or prop tip on the 'right' side of the plane.

I generally drill one mounting hole in the mount and swivel the engine on the installed bolt as I adjust the motor. The mounting bolt can apply light to moderate pressure to keep the motor from swiveling too easily. Once the proper placement is found for mounting the engine it must be marked somehow so that you can drill the remaining mounting bolts. If you place masking tape on the motor mount where the engine will touch (before you install the swivel bolt I mentioned above) then you can swivel the engine until it is in the right place and then draw marks onto the masking tape inside the unoccupied engine mounting holes. Then remove the engine, drill tiny centering holes (they do not have to be deep) through the masking tape into the engine mount, remove the masking tape, drill the holes to final size and mount the engine.

If the wingtips were also aligned using the same method (the leading edge of the wingtips or the trailing edge of the wingtips is equally distant from the enter line near the tail) then the prop and wings will align with the center line of the fuselsge, which is good.