PA-18 Super Cub for the BMFA R/C Scale Indoor Nats

Thanks Andy, wise words indeed. My subject has been completely rebuilt 4 times that I know off, so it is also important what pics of the subject you have are from the same period.

Cheers
Danny

I just re-read my post from late last night and I reckon you will have done well to have understood my ramblings

Here are the bounding boxes as promised, these are the extremities remember. I now have to make the cut through sections fit inside the boxes and extrapolate or "loft" the ones in between. All good fun....




Cheers
Danny

Well the first page is printed, just to get a feel for the size of things




Cheers
Danny

Danny
That looks very nice.
I just cannot resist detail - I must suffer from OCD!
This pic seems to suggest the rear fuselage structure is braced slightly differently with what I believe is called a "Sub divided Warren truss".
Also interesting is that the "formers" of the top half of the fuselage are clearly not load bearing in any way as their positions do not correspond to the bracing points of the structure underneath! :ohmy:

In many respect Auster's take on the fuselage design is a bit more logical given they both originated from the Taylorcraft.

Shouldn't diagonal brace number five go the other way?
That way it completes the zig-zag stress transfer pattern, and also extends the cabin upper brace loads to the lower stringer.

Lol probably Eric, that would mean that there was more than random scattering of diagonals.....

Okay the beauty of CAD is that moving a few lines about is very easy. Does this look better?




Hope so because I have started putting the fuselage together, building with 1/16 square is proving challenging to say the least!

Cheers
Danny

My worry would be that 1/16 square has insufficient strength to support the tissue covering on a model this size Danny. Hope it works out OK, but you may find the longerons pulling in between the upright and cross members when the covering is shrunk

Hi Martyn, I am also concerned about the strength but we wont really know until we try. I will not be using a shrinking dope, purely water and banana oil as per a chat I had with Peter Ilife a few weeks ago.
We shall see

I think you will find that water shrinking will still pull the tissue sufficiently so that it "bags" down the length of the longeron. We used to notice this even using 3/32 square leading edges on tail planes and with a rib spacing of abut 25mm. Maybe worthwhile making a simple test frame as a confidence booster.

There are a number of 'tricks' to use to prevent the 'starved horse' look:

1. Pre-shrink the tissue and iron it before attaching it to the model, or

2. Shrink with a light touch of steam. Repeat as necessary until the required shrinkage has been achieved, or

3. Use meths as a shrinking solution rather than water.

...and as Septic so rightly says, use banana oil to finish the tissue, which is simply a non-shrinking dope with added plasticiser. If banana oil is not available, then non-shrinking dope with a few drops of medicinal caster oil works just as well.

Thanks chaps. Isn't it always the way.... I just registered on Aerofred and immediately found some Cub plans that are infinitely simpler in their construction that what I have gone for... I can either bin all the work and build from somebody elses plan or carry on. After a choccy digestive and a Roma, I am going to keep going
First of all my carbon rod arrived, this is 0.28mm, 0.5mm and 0.7mm. I already have some 1mm but that would be too heavy for this......









Cheers
Danny

Look back at post 67. Those diagonal have gone wrong again in post 72! [badass]

Tee he, No they havent. If you look closely the balsa parts do not match the plan they are pinned too. I had already started the fus side before the redraw. Didnt want to lift it and substitute the new drawing until the frame work was more rigid. Done now, so I am building over the newer drawing
Cheers
Danny

Septic
Where are going to use carbon rod?