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Jocasta build


Mowerman
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Hi Glyn,

You can use very thin material for the windscreen - it has no load bearing properties at all so it only has to be strong enough to retain its shape. It would be perfectly acceptable to cut up a soft drink bottle to make a suitable piece of clear plastic.

The windscreen on the prototype is cut from flat acetate sheet; to determine the shape, use a piece of paper and cut it roughly to shape before holding in place against the model then trim and refit as many times as necessary to achieve the look you want. The actual angle of the windscreen is not important - just get it looking how you want.

As far as fixing it in place goes, the top edge can be glued to the canopy support piece very easily using canopy glue (cyano would work but it will cause fogging of the acetate). The two side areas can be glued with more canopy glue but they will have a natural tendency to spring apart and away from the former, so I use a couple of dress maker's pins to reinforce the joint - if you coat the pins with a thin layer of epoxy resin before inserting them they will stay in place forever. The lower edge of the windscreen is not glued to anything - it doesn't need to be, in fact it is quite common on models of this sort to leave a gap at the lower edge for cooling purposes although on Jocasta adequate cooling is provided elsewhere.

Attached is a picture I took this evening of the windscreen on the original Jocasta - this model is now a couple of years old but hopefully you can see that the windscreen is still in place and has required no re-attaching. The pin heads are just about visible and I don't think they detract from the look of the model, especially as they are pretty much invisible from a few feet away.

If you need any more help please let me know.

Jim.

image.jpeg

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Ah Brilliant Jim. I have done what you said. I used my piece of flat sheet, after making a paper template. I found I could create a permanent curve in it after cutting to size, by dunking it in boiling water, and holding the shape until cool. I shall glue it on tonite hopefully. Then I'm done at last! Pics to follow soon. Oh no just looked at your pic and see that I have to male and fit some sort of sheet ( skirt? ) finish to the wire landing gear. Ply or foam I am guessing.

Thank you again Jim, very much appreciated,

Kind regards, Glyn.

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Glyn

I have done infills on mine, after a fellow club member kept telling me it would look better, I use some offcuts of EPP I had in my scrap box, attached and covered with Yellow packing tape. A bit fiddly to do as the tape will not stick to the EPP bur sticks to the wire well enough to hold the EPP in place.

As Jim says it does nothing for the aerodynamics but stops Malcolm telling me how much better it would look wink 2.

Roy

Edited By Mowerman on 10/11/2015 16:40:15

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  • 9 months later...

First flight today. Suspect some wing warp as when trimmed for level flight the right aileron is 5mm down. Going to try to fix by bending the wing appropriately a then shrinking the covering to hold in the new position. The wing tends to shift aft, as there seems to be inadequate lip to stop the trailing edge riding upon to the top of the fuse. Probably fit some sort of peg to fix it solidly in place. It has been completed for about six months before today, just never got around to getting into the air.

Apart from that a very gentle easy flyer. Next project as yet unknown. All is well as home in one piece.

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Exactly Glyn, I buddy up a novice on the Jocasta regularly, and even today! In the good weather. Every time the model was assembled, there was a significate re-trimming of the model, due to the band fixing. The owner has over the weeks, made the rear cabin lip more secure, and added asmall dowel locater to get the wing central each time.

The model has huge ailerons that need turning down, and the take off run is never at full throttle.

We apply progressive throttle, whereby as half throttle is reached, the model ascends under control

At full chat it is a struggle to take off without a huge swing

Having learned to fly the Jocaster, it is very forgiving and a doddle to land under power.

It is no way a good "dead stick" glider, it comes down fairly quickly without power

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