Greyhead

I’ve said before that I like to get the positions for the radio gear sorted out as early as possible in the build so as not to get any nasty surprises at a later stage, after all the whole purpose of the exercise is to produce a radio controlled model! Unfortunately, although I confirmed the principle for the aileron control very early on in the build, the practicalities of actually fitting it into the model could not be worked out then because I had no idea how much spring tension would be needed or how much “slack” the system would have.

This is the design that I tested to prove the principle.



I fitted the spring temporarily using the inserts from an electrical connector strip and adjusted the tension as necessary. Because of the tension I had to reduce the length of the cable joining the top ailerons slightly then all worked nicely.



I was surprised to find that as with the elevators there was no noticeable tightening or loosening of the cables and the tension required was the same, ¼" plus a bit for safety; I’d expected to have to use about double as the one cable controls all 4 ailerons, runs round 4 pulleys and there is a lot more of it.

Fitting the spring the way I have done has given me an idea; I’m going to turn the design “inside out”, that is I’m going to attach the spring outside the servo arms not between them as originally intended. Doing it this way means I’ll be able to move the servos a lot closer together, which will mean less bending of the snake inners, which in turn will make for a smoother and more precise movement of the ailerons.

Having got to this stage I couldn’t resist the temptation to fit the wheels and take a couple of photos.





Looks a bit “naked” without all the wires, Lewis gun and a pilot!

alan2525

It's the photo we've all been waiting for! The SE5a looks beautiful assembled! I bet you can't wait to don the flying goggles, silk scarf and prepare for take-off!

The white lettering, red wheel covers and markings really do lift the dark green too. It looks superb!

I must admit that those paving slabs look a little incongruous though!

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John

What amazes me apart from the brilliant job your doing with this build and the helps and tips your giving to others, is the fact you have time to photograph and write about it in such detail.

Bluewavestudios

Grahame,

I am very impressed with the photo's, she does look the part indeed, Somewhat Ironic set against a hexagonal patio background and the Pfalz having already been mentioned as a possible next subject for you !!

I have a feeling those hexagons are going to be haunting you for a while yet !!

Regards.....Mark

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I'm Only Here Coz I'm Not All There !!!

wonwinglo

Looks beautiful Grahame,it does not seem that long ago that you laid down those few few pieces.

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'And there I was oil on my goggles from a broken pipe,then I looked at the altimeter,all I could see was the makers name !'
www.wonwinglo.scale-models.net/

Bunkerbarge

Grahame, what can we say!! Beautifull does not do it justice! I am going to wait for the shots with the gun and the pilot fitted though to get the full impact of this amazing model.

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“Dirty British coaster with a salt-caked smoke stack, Butting through the Channel in the mad March days"

Greyhead

Thanks for the comments; I’m glad I took the photos because the wings are off again for fitting the wires etc but at least I can visit the site and see what it looks like assembled. I have to admit that it’s not the best background but I’ll wait until the model is completely finished before take any more and hopefully
it’ll be warmer weather by then, believe it or not we had a dusting of snow here yesterday. I’m hoping to get permission to use Fishburn aerodrome, they’ve got some “old fashioned” hangers there so if I can get the perspectives correct it could look quite realistic.

I was discussing the aileron linkage today and was asked “why use the spring if there’s no slack?”. Well the first thing to say is that I said “there was no noticeable tightening or loosening of the cables” not quite the same thing, but anyway the cable needs to have some tension to keep it in the pulleys and make them rotate, without the spring this tension would have to be supplied by the servos working against each other. Stalled servos drain power from the battery very quickly and the result can be disastrous. I had considered using a true closed loop system with the cable itself providing the tension but I feel the set up would be quite critical; the spring gives that bit of leeway

Greyhead

The wings are now joined together and I’m very glad to say that it’s no problem attaching them to the fuselage; if it had turned out to be not viable to disassemble the model for storage in the shed I would have had a lot of grovelling to do to the better half!

I had thought that the wings would be quite “wobbly” when held in the frame but in fact the assembly holds itself in position quite well. The photo also gives a good view of the underside weathering and the inspection “window”.



The interplane struts are held in position with bent pins with only the bent section epoxied to the strut; if needs be it should be fairly simple to remove them. The struts only really need the pins to hold them in place until the model is assembled, after that the struts are always in compression so they really hold themselves in position on the pegs.



The front flying wires are permanently attached to the fuselage bracket; the 2mm stud goes through a hole in the fuselage side just above the front undercarriage leg and is held tight by a nyloc nut.



On the full size the rear flying wires are attached to the fuselage inside the lower wing stubs. This is impractical on a model of this size so these wires end inside the wing stubs joined by a length of brass tube.



The SE5a has a very thin wing section but the model has sufficient strength, thanks to carbon fibre spars and LE, to not actually need flying wires, except for show, so it is perfectly feasible to just leave the wires loose. I don’t really like that idea though as I feel they might “flap about” uncontrollably once the engine is running so I’ll devise a way of applying at least some tension; either flexible “tails” attached to the wires themselves or hooks on flexible wires inside the wing stubs, I’ve not decided as yet.

Greyhead

For the last few days I’ve been experimenting trying to make the tail plane support wires from 24swg piano wire. I made various ends using brass and aluminium tube but none of them looked right; they were all too “chunky”. In the end I decided to try bending the wire to the exact length required, doing this meant there would only be 2 wires in the “ferrule”, which could also be a lot shorter as it isn’t functional. This was not my preferred method as I thought it would be a problem getting the bends in exactly the right place but as it turned out it wasn’t too difficult, of the 8 wires only 1 had to be scrapped and re made. The ends are made from a sort length of heat shrink tubing, which is very thin walled, painted silver; they still need to be “dirtied up” a bit but the overall effect is certainly a lot better than the fishing trace.



When assembling the model I have to connect the 4 aileron cable quick links, this is a bit awkward as there is only a relatively small gap between the centre section and the wing root rib. To make things easier I’ve made a small “ tool” to hold the links open, as a bonus it also stops the links disappearing into the wing tubes!



It is simply inserted into the link and turned through 45º. It’s easier to see how it works using a link that is not on the model.

Lips McGee

Without a doubt a true work of art and a fine example of exactly what our hobby is all about. Many thanks for taking the time to teach and demonstrate. More so, thank you for sharing this masterpiece with us all!