Airco DH2

Rather than build another kit I have decided to build an Airco DH2 from plans on the Outerzone site & printed them out on A3.
The plans were for a 38" electric R/C but am scaling it down to 28" span for rubber power on account of I have neither of the hitec items.
The propellor sits in a cut-out in the rear of the wing so that's a critical dimension.
On the A3 plan the span measures 470mm (2 x 235) so scaling that up by 1.5 x gives 705mm and a cut-out of 210mm.

I have a copy of Autocad 14 but it only works on my XP emulator which won't talk to my printer so it invoves a bit of jiggery-pokery to print out at the correct size.

I had intended to cannibalise a glider kit to get the wing ribs but the OZ plan specifies a Clark Y section which is completely new ground to me.
However I have found a site which will print one out so I have put some numbers in & am going to try making my own.
The OZ plan specifies 1.5 deg incidence, & it looks on the plan as if the flat bit of the bottom of the section is 1.5 deg from the horizontal. To get the flat bit on the Airfoil Plotter horizontal I have to enter 2.1 deg in the pitch box.
Is this the same thing or do I just cut out the shape with a flat bottom & use it like that?

airfoiltools.com/plotter/index?airfoil=clarky-il

On the airofoil sit it shows the line from the centre of the leading edge so what is the aoa?
I have played around with the numbers & have seen it produce a concave camber.
The pitch of 2.1 deg gives a flat bottom which the OZ plan uses as the build zero, parallel to the fuselage centre line.

I have printed out a section of the correct size & scanned it back in & am now tring to use Paint Shop to draw in the cut-outs for the edges & spars,
 

    Its early days yet but this shows an angle between the bottom of the wing & the tail plane.
Presumably I can pack the tailplane at the glide test stage.

Magpie
At the size you are building coupled with the fact it is a biplane of dubious aerodynamic efficiency I really wouldn't worry too much about the absolute accuracy of the wing section. Of far more importance is the left and right ribs are exactly the same and there are no twists in the wing.
By the same token the effectiveness of the tail plane is, particularly in a biplane, effected by the airflow leaving the wings. Just make sure you can adjust the tail plane incidence resulting from test glides. It will be pure luck if it is right first time.

I built a small Fokker Triplane and found the tail plane leading edge needed raising considerably to what looked like even more incidence than the wings. I did some research and to my amazement the few period pictures showed the full size was exactly the same. Apparently the down wash from the three wings meant the airflow of the tail plane had a significant downward path hence although it looked like it had a positive incidence it was actually in line with the inflight airflow.

I am not too sure the short DH2 fuselage is ideal for rubber power and the tail plane out on 'booms' might be a bit crash 'delicate' but I will follow your build and flying with interest.
.
 
 

Apparently the actual aircraft had a bad reputation, being nicknamed "The Spinning Incinerator" at one time. I have only just learnt that in rotary engines the cylinders whizzed round with the propellor & they often fell off!

I'll make the tailplane adjustable with rubber bands like a glider's wings to start with.
Am I right in thinking that the tailplane acts like a lever and tries to hold itself level - or at least in line with the airflow or downwash from the wings.
The OZ model used eighth square spruce for the booms & it had a third longer wingspan.

I have seen a photo where the rubber was between the booms which would make it awkward for winding it up, (as did starting it on the actual plane).
I've thought about winding it up from the nose via a rod or even having another length of rubber in the fuselage.

Because its very early is part of its appeal, & also its unusual design, I've always fancied building a Canard!

This video shows an actual plane flying.....

Yes I realise that, I meant it as an alternative , obviously not writing what I meant.

It mustn't have been a photo I saw of the rubber motor in the tail boom, it was this drawing.
Wound from the nose via a knitting needle - it even gives the size!