Greyhead

One problem that has been causing my some concern is the way the top fabric is fixed to the longerons; they appear to use some sort of dome head fixing which shows through the side fabric. The only way I could think of was the “drop of glue” method after all the covering has been applied, but as I said earlier I’m not keen. Why they don’t use flat heads and make life easier for us modellers I’ve no idea!

Whilst searching the shops for something suitable as a basis for making the trim wheel, I came across some very small beads, about ½ mm diameter, which should do the trick if glued to the longerons before the covering is ironed on. These were sold in a haberdashery shop and are for decorating home made birthday cards I think. I must admit that I get some peculiar looks as I rummage through the boxes in these shops, the other customers are invariably women; the things we do in the name of aeromodelling!

Back to the trim wheel, I couldn’t find anything so had to resort to building from scratch; I printed some templates on self-adhesive labels and cut out 3 blanks from 1/32 ply.



These were assembled, the rim marked at 18º intervals and half circles routed out. It didn’t work out as accurately as I’d like but a bit of filling using epoxy and micro balloons made all the difference. After 4 coats of sanding sealer it’s ready for painting.



A coat of silver Solalac, with a few extras the end result is good enough, especially as it will be mounted low down on the fuselage side so only the top section, as shown below, will be clearly visible.

Greyhead

With the majority of the cockpit furniture ready I’ve started on the decking from the tank cover to the cockpit, which is not as straightforward as it might be!

The decking from the tank to about 1/3rd of the way back along the cockpit opening tapers up then it tapers down towards the tail; add to this the fact that there are no formers, only stiffeners, and you can appreciate the problem. I decided the only practical way was to make a jig and build it off the model, as there is a transparent inspection hatch for the Vickers I can’t cheat and add hidden formers.



The cut outs are where the stiffeners fit and you can see by the differing formers how the curvature of the decking has to change.

I clamped a layer of 1/64th ply in position on the jig, gave it a generous coating of watered down aliphatic glue, applied glue to another layer of 1/64th ply and clamped them together.



Then I left it overnight to really dry; in the morning I got a pleasant surprise when I removed the clamps, it held its shape, a bonus I wasn’t expecting.



With the success of the layering technique I decided to try making the stiffeners from 3 layers of 1/32nd ply; the first one is a complete “hoop”. The decking is covered with Clingfilm and the laminations held with small wedges.



Once again I’ll leave it overnight; I’ll post an update tomorrow.

wonwinglo

Interesting this Grahame,Aliphaetic resin will hold its shape as it cures and dries in a more brittle fashion to standard PVA,the latter tends to be a trifle rubbery,and thus not be as stable,you too have discovered this quite by the happy accident so to speak.

__________________
'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/

wonwinglo

No need to apologise over your trim wheel Grahame,it looks superb !

Greyhead

The stiffener has worked well and far more evident is the differing lengths of the laminations; with using 3 pieces of 1/32nd ply the inner lamination is about ¼ " shorter than the outer. When these are glued together it helps to explain how they hold the shape.

Before I can make the other 2 sets of stiffeners I’ve got to cut out the cockpit opening in order to alter the curvature of the decking; transferring the top and side views of the opening onto the curved decking isn’t such an easy task. I’ll tape some paper to the decking and then use a lot of trial and error until I get an acceptable outline, make a template from this and only then commit to cutting the wood after checking again that everything looks right!

wonwinglo

And the cockpit apertures are never shown very accurate on scale drawings anyway,one way is to lay a piece of Fablon onto the decking,work out the shape with a Chinagraph pencil ( obtainable from art shops ) straight onto the material,checking in particular the shape from the side view in relation to the actual depth using a photograph,then once satisfied cut straight through the fablon and laminations,this avoids the miralyte ply from having a ragged edge,then carefully peel off the adhesive film.

__________________
'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/

Greyhead

Well I should have read that last post before I started but it’s too late now! I used a paper template in much the same way . I must say that the stiffener looks and does its job a lot better that I thought it would.



But I have inadvertently caused myself a bit of a problem; with the decking being that much stiffer than I thought it would be it’s quite difficult to get the sides to conform to the correct shape.



With hind sight I should have cut the cockpit opening in both layers before I glued them together and clamped them to the rear former as they dried; I’m sure I’ll get it sorted even if I have to make back section take up all the change in curvature, not quite scale but I’m sure no one will notice.

Bunkerbarge

If you do something and you are not happy with it the only real solution is to do it again.

You will never be really content with the job f you don't. I did an area of decking that just didn't work out well and much as I told myself that it would be OK and no-one would notice, both of which were true, I was only really happy with it when I did it again.

You owe it to the rest of the model and all the time you are putting into this project to be completely happy with every single piece.

__________________

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

Greyhead

Richard

How right you are, I think I was a bit hasty with the last bit of the last post; the curvature isn’t that far out so I’m sure I’ll be able to bend the sides to the correct shape. After all we really build these models for our own satisfaction don't we?

It just “took the wind out of my sails” a bit; thinking how well the decking had turned out being that rigid and then to realise that in actual fact it had caused a problem!

wonwinglo

Grahame,I have had this very same problem with laminated miralyte,it tends to have a will of its own at times,Dave Boddingtons method was to apply ammonia to the ply prior to bending,a smelly nasty process but it does work,the reason why it has done this is because to a degree the ply has taken its own course and bulged to the natural curvature of the materia itself,what the ammonia does is to relieve the stresses in the ply laminate internally,I am assured that once dry it returns to a rigid state.
How about this method-Whilst you have the internal shape of the formers,why not take it one step further by making a couple of 'outer' ply shaped clamps,these could slide over the two laminations to hold it into shape and make sure it nips the sides cosily,the old woodworkers used to use this idea by making temporary clamps then to discard them,just a thought.

__________________
'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/