vease

Although in the UK I am building an OHIO 540 profile as I had the plan sent over to me. This is because profiles pretty much don't exist in this country.

What I am surprised to see is that the trailing edges of the elevators and ailerons are to be sanded to a point. This seems to go against what is needed for 3D flying in that all other models I've seen have square trailing edges.

Is this correct. Do I sand to a point or leave them square. All the pics of them on the OHIO website seem to be square??

3D DEAN

The trailing edges are 1/4 inch triangle stock. The plans call for you to glue the triangle stock to the edge of all the control surfaces. No sanding.

vease

The triangle stock goes both on the trailing edge of the wing and leading edge of the aileron where it hindges. It actually says in the plans, sand the trailing edge of to a point.

Scott G

I just sanded mine round. Of course I am not an aerospace engineer so what the heck do I know...

Scott G.

tecme

If you sand the trail edge of your control surfaces (ailerons for example) you''ll loose strength, go with your gut instinct and keep it strong.

ChuckAuger

My Feedback: (12)

I had to pop the CD in and take a look...that does seem strange, but Mike has it like that on the ailerons and elevators.

With all due respect to Mike, I'm leaving mine squared off unless Mike pops in here in about the next day or so and tells me I'm about to make a grievous error by leaving them square.

BotleRocketWar

As far as I know, there are two ways the trailing edge of a control surface should be.

Either completely flat (no sanding, Chuck knows that's my favorite) and the other is sanding it or using tri-stock so it comes to a point. Both are OK as far as "flying" goes and neither will cause or contribute to flutter. The flat TE is usually considered to be better though and is MUCH more common.

I'd go with the flat simply because I think it looks better (see Chuck, there is a reason for it) and the strength. I can break a flat TE, don't even want to mess with a pointy one!

ChuckAuger

My Feedback: (12)

I have to admit..enough sanding to get the ailerons/elevator to a point would be more than even I would like to do (it's WAY more than sanding the LE of a Sledge, for example! ) and I'm a firm believer in sanding. I'll take me chances with square...

vease

This is where I wish I had started this thread before the sanding process!!!

I have tapered the ailerons and elevators already now. Not to a total point but still tapered. Not and easy job at all and now wish I hadn't. I can see me re-building them at some point!!!!

Cheers for the reply's though chaps. The designer should read these and take note.

JRozman-delete

My Feedback: (2)

Vease, I rounded mine, don't sweat it. It has been going strong for over a year of hard-core flyin'.

Jess

ChuckAuger

My Feedback: (12)

I just started mine, Jess. I'll have it with me in Nashville.

You said you rounded them..but you didn't go all the way to a point, did ya??

JRozman-delete

My Feedback: (2)

Chuck, I just rounded. No point. By the way, a buddy of mine left them square and I can't tell the difference. He has a OS 50sx on his. No flutter problems.