Scale Soaring UK

Top sheeting being added with the wing supported on its profile supports to retain the correct incidence. The wing needs all the supports shown to avoid any distortion as a consequence of the iron pressure during the hot PVA gluing process.
Centre hinge for the frise ailerons - only three hinges on each aileron and all will be installed and pinned before the ailerons are cut from the wing.

Aileron hinges installed 2mm below the surface of the aileron and the aileron cut free.

I breathed a sigh of relief when the released surface moved freely throughout its travel. In fact free enough to rotate almost 180 degrees down without binding. Problem is, the whole assembly is designed to be held in position by the removable tips but unfortunately I have discovered in order to then slide the aileron out of the centre and inboard hinges, the aileron spar has to be cut away leaving little more than the fabric covering holding the two halves together. Not good. So, the centre and inboard hinges will have to be modified using removable pins (as per full size) and the centre hinge bracket also modified by reducing its depth considerably. Ah the joys of prototyping.

6mm balsa to be added to the LE of the aileron to be shaped to give a rolling clearance over its travel within the shroud.

The frise aileron with its leading edge applied - difficult to get the correct rolling clearance over the whole travel.

The gap underneath really opens up on the down going side and the hinge geometry is set almost identical to the full size.
The leading edge profile.

Ah, another Phoenix rises from the ashes (as does the balsa dust).

Profiling the aileron leading edge shrouds on the right wing - what a faff. The profile is not a straight radius, it changes top to bottom and has to be identical in both wings as the gap at the underside changes depending upon the ailerons position so it's got to be right in both wings.


To further complicate matters, you will see from the photos below the gap increases from root to tip. Anyone any ideas as to why?

.................and they won't be like that on the model Cliff because to my eternal shame I have only recently noticed that. Everything is now set in stone and isn't going to be changed.

I suppose I will just have to come to terms with the night terrors and bed wetting, waiting for the Scale Police to get on my case.

I suppose I will just have to come to terms with the night terrors and bed wetting, waiting for the Scale Police to get on my case.

Might as well be hung for a sheep as a lamb, Robbie...paint a fake moustache on the front then sit back a wait for the explosion!

Don't you have an I-CROZ to fix????



BC

I have been thinking about how to go about the aileron pushrod shrouds on the 100 which are almost certainly glass on the full size:


To make such a thin thin walled shroud I opted to do the same. Unfortunately when I opened my bottles of epoxy laminating resin the catalyst was a most definitely 'off' colour.

So, make the plug out of balsa - too small and fiddly to use foam:



Pull a small piece of light glass cloth over the plug as normal:


Soak with watery cyno:


Trim off and repeat with second layer and then remove the balsa plug with the Dremel leaving a nice, thin walled, flexible but strong shroud:


That one is a bit rough as it was the first experiment.

The big advantage here is, it's very quick and you don't have the inconvenience of mixing up the epoxy resin or trying to keep the glass cloth in contact with the very small plug while it cures.

I think the real secret of success here is knowing when to put the Dremel down and finish hollowing out with sandpaper.

RobbieB wrote: ↑22 Jul 2018, 17:20 Ah, another Phoenix rises from the ashes (as does the balsa dust).

Profiling the aileron leading edge shrouds on the right wing - what a faff. The profile is not a straight radius, it changes top to bottom and has to be identical in both wings as the gap at the underside changes depending upon the ailerons position so it's got to be right in both wings.


frise_shroud_rw.JPG


To further complicate matters, you will see from the photos below the gap increases from root to tip. Anyone any ideas as to why?


mesange4.JPG

mesange 7.JPG

Robbie the reason for the increasing gap towards the tip is to increase venting and drag which helps with adverse yaw on rolling the glider. It is of little consequence in our realm of flying. Even the Scale Police would have been very eagle eyed to spot it on the model. Keep going , good work. Regards John.

Thanks for that info John, I knew there had to be a reason for it.

I'm sure you're right, none of this should matter a lot down at our scales but that said, I have no idea how these frise ailerons are going to perform.

Anyway, after the nightmare they have been I'm more than ready for the Scale Police. Certain phrases containing references to personal anatomy and sunshine immediately spring to mind....................