Thank you for your highly detailed build log with great photos and explanations of your building techniques.
Much appreciated!
Mike F
Re: Scratch built Slingsby King Kite 1/4
Posted: 10 May 2021, 16:15
by Bovin
Thanks Peter and Mike for your kind words!
I also learned a lot from all the info on this and related sites or fora, for example the PVA with a foil iron technique, so I am glad to do something in return. (my parents used to be teachers ...)
Vincent
Re: Scratch built Slingsby King Kite 1/4
Posted: 16 May 2021, 19:41
by Bovin
The wings are completely sheeted. Again a lot of panels, glued with the same technique, dried PVA and fixed with a foil iron.
I have some doubts how that sticks to the balsa ribs, I think I should apply 2X PVA on them, now that the wing is still “open ”, I can apply some extra glue, but when the top goes on, that will no longer be possible. As I got closer to the wingtip, I found that an extra pivot point for the aileron was needed. First drilled an oversized hole and then glued an epoxy bearing plate to the rib.
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With a long batten with sanding paper I sanded the edge of the sheeting straight .
The sheeted wings look very strong!
Vincent
Re: Scratch built Slingsby King Kite 1/4
Posted: 22 May 2021, 11:00
by Bovin
I now sheeted the topside of the wing, pre-priming the balsa ribs with PVA, that seems to work better.
Next I had to trim the back of the sheeting for the ailerons and flaps. By the way, I had already done that with the bottom sheeting before applying the top sheeting. I did this by drilling a few 1mm pilot holes with the hinge pins as guidance and cutting the plywood along these holes. Of course there was still a lot of sanding. When the top of the wings were sheeted, I just repeated the process.
The ailerons and flaps remain demountable, just like that of the horizontal stabilizer
I plugged in the leads and to my relief it all worked.
The wings are now roughly finished weigh 936 and 942 grams.
Vincent
Re: Scratch built Slingsby King Kite 1/4
Posted: 23 May 2021, 11:53
by SedB
A very nice build so far, I enjoy to see is all come together!
The wings look great, I wonder how you achieved so little difference in weight between the two? Did you weight them in between, or is this the result of working precise?
Daniel
Re: Scratch built Slingsby King Kite 1/4
Posted: 23 May 2021, 17:21
by Bovin
Thank you for your nice comments and yes I am also looking forward to see it as a whole (I had a small preview ).
The weight of the wings is purely a coincidence, what helped that not much balsa is used, ply for sheeting, spruce for spars? only the ribs are from balsa, but it was selected balsa, all medium.
I found it difficult working with balsa ribs and the spruce, sanding is very tricky, but I am very pleased that the wings didn't turn out heavy.
Vincent
Re: Scratch built Slingsby King Kite 1/4
Posted: 24 Jun 2021, 14:33
by Bovin
In the real glider there is a gap between fuselage and wing to get to the connecting gear.
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This gap is covered with a curved strip of plywood
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I tried to replicate this. The wing of my model slides over the square glass epoxy wing connector and is secured with a nylon M3 bolt in plywood lips on the fuselage and wing.
I made a constructing aid consisting of 2 ribs (equivalent to the root rib). On this I clamped plywood with two rows of 3mm holes. On the inside I put first 2mm balsa and another strip of plywood.
Holding the inner plywood in place with my fingers, I ran thin cyano through the holes on the balsa. I made a nose piece
and also an upper and lower piece up to the TE. Then I glued the three pieces together, and cut it lengthwise forming the two filler pieces. I glued magnets to the rear to secure it .
,
This piece now fits exactly in the gap and I glued 5mm wider strips on top, that fit just over the wing and fairing on the fuselage. You slide it over the wing
and click the magnets
To my relief It suddenly formed a visual unit with the fuselage.
Vincent
Re: Scratch built Slingsby King Kite 1/4
Posted: 24 Jun 2021, 14:44
by Bovin
It was time for the interior, first the pilot
The pilot is very visible, nice to make proper job of it. My sister wanted to make the clothes, but then I must have a figure first. I used my own measurements (a bit photoshopped....) and made the parts from 10mm balsa
In the elbows and knees I fitted Hobart hinges,
the hips and shoulders I fixed with shockcord
In this way you get a figure that can be positioned naturally.
To attach the balsa boots I have glued a piece of M2 threaded rod in, which fits into a plastic tube (control tube stuff) in the lower leg. A small bend in the M2 wire provides some friction, just bend it carefully a little. The hands will come with 1mm copper wire in the arms and the head with 10mm beech dowel in the chest. Hands, feet and head remain removable, much easier to get him into his clothes.
In the meantime I started with the head, made of sculpey (a kind of clay-like plastic, which is baked at 140gr). This tutorial gives a wonderful explanation, but it is a time consuming job
I start with beech dowel of 10mm, wrap aluminium foil around it (the head may not be solid, it might crack when baking) and then I build the head from layers sculpey
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Schermopname (14).png (51.91 KiB) Viewed 3203 times
It takes me a while, but it's nice work and it starts to look like something (I hope a pilot...)
Vincent
Re: Scratch built Slingsby King Kite 1/4
Posted: 24 Jun 2021, 17:54
by Phill Tadman
Fantastic work!
Re: Scratch built Slingsby King Kite 1/4
Posted: 24 Jun 2021, 22:28
by Bovin
Thanks for your nice words Phil, it is also a remarkable glider, nice to work at it!