DX7 flap set up

[Peewhit]

Hi folks,

 

I am looking at a four servo wing set up on a slope soarer - ie separate ailerons and flaps, using an AR6250 carbon friendly receiver.

 

Both flap servos will be connected to the gear channel and operated via a p-mix from the flap channel. Using flapperon mixing for ailerons, they should then move in conjunction with the flaps.

 

Both flaps obviously will need to move in the same direction therefore the flap servos will need to move in opposite directions - one clockwise and the other anticlockwise.

 

Do I therefore need a standard y-lead or, as I suspect, a reversing one?

[Frank Skilbeck]

Couldn't you use a free mix to mix in the flaps so they work on the throttle stick, much better than using a reversing Y lead. Hook up one flap to the throttle channel and the 2nd on the gear channel then mix gear to throttle.

[Peewhit]

Hi Frank and thanks,

 

Am using the three position flap switch for normal, thermal (down flap + aileron) and speed (up flap + aileron) and reserving the throttle for crow braking.

 

So do I need a reversing y-lead then?

[simon barr]

Can you not just mount the flap servos so that they both face the same way, ie both output arms facing to the right for example? Then they will both operate in the same direction on a normal Y lead...I've tried a reversing Y lead, but they have an adjusting pot which caused me endless trouble...

[Frank Skilbeck]

Shame you can't go the mixing route, this is what I do on my Cockpit Sx, throttle stick works crow and flap slider is set to give thermal, normal and speed flap settings and I then use the flight phase switch to enable aileron to flap mixing so flaps move with the ailerons for crisper aerobatics.

[Peewhit]

Thanks Simon for the advice on reversing y-leads and to Frank for the mixing advice.

Could go for the mixing route but would then need a seven channel receiver and space is very tight for the remote unit, hence the attraction of the AR6250.

With the DX7, I would have a choice of either flaps working with ailerons

for crisper roll or ailerons working with flaps for thermal normal and speed settings.

Could get both of these but then crow braking - an absolute priority - could not be achieved.

So, is it ailerons with flaps or flaps with ailerons?

Any advice would be appreciated

[Frank Skilbeck]

Well to be quite honest it probably depends on your flying style, I could have both on the Sx but don't bother mixing ailerons with flap on my Mini Blade and to be honest I don't ever use the speed setting but have found thermal useful in very light lift. But the flap to aileron mix I use all the time. Maybe you should set up two model memories and try both options.

 

I take your point about space being tight, I had to get a Corona Rx (35 mhz) to fit in the blade as my regular 7 channel Rx's wouldn't fit.

[Adrian]

You could use a V-Tail mixer instead of a reversing Y lead. If you connect the mixer to the GEAR and THRO channels you can the mix a percentage of aileron to throttle to get reduced aileron on the flap servos. As you noted, you can also program crow braking.

 

N.B. you need to be careful which v-tail mixer you get; not all work with Spektrum as the timing is different from most receivers.

 

 

Edited By Adrian Aylward on 19/11/2009 22:05:05

[Peewhit]

Thanks Adrian for another possibility.

 

Think I have a neat solution for the y-lead issue, but it's a bit hard to get your head around these things at times.

 

If I mount one of the flap servos upside down then the arm will stick up from the "bottom" and move in the opposite direction.

 

Could then use a standard y-lead, couldn't I?