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Is it a boat? Is it a plane? Is it a snowmobile? Yes on all accounts!


Torbjorn

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Take 2:

j6YMgJv.jpg

 

More even spacing now - I call it finished. Added wires for rudder and elevators, though I need a new camera to be able to portray them. The angled beams, integrated with the bulkheads, will hold the wings.

 

Also worked on the hull. The tail is rather specific, triangular in shape, bent upwards and tapered. I could not mould this, so another solution was necessary.

For those interested the shape of the tail of a this century old lady, see e.g. here:

http://www.wwi-models.org/Photos/Fre/DonnetLeveque/index.html

 

 

Some years ago I bought supplies from an Internetmodelshop and ordered - among other things - some (circular) plastic rods: when I opened the package the rods had magically turned triangular. Not liking having made bad business, I will try to get some use of these now. I tapered the rod (or whatever it’s called when it has a triangular cross section), and manually bent it after heating it in the toaster:

 

GckAONm.jpg

 

This now has to be mated to the moulded part. Picture says how:

hWz623C.jpg

 

I started making drawings for the wings. Measurements were taken based on photos, data from digitalmuseum, drawings (with correct-ish hull but bad wings). Making comparisons and verifying with whatever reference distances to be found, I came of with these dimensions:

All in scale [mm] (i.e. 72 times smaller than real):

Upper wing:

Span: 161

Chord: 23

 

Lower wing:

Span: 115

Chord: 18

 

Height between wings: 23 mm

 

This means the separation between wings is identical to the original, while the upper wing is considerably wider and the lower wings somewhat wider.

Edited by Torbjorn
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Thanks gents - I am beginning to think I should have chosen 1/48 or 1/32 as my go-to scale for Great War era aeroplanes. 

 

I have started on the wings (with the method described by Woodman in his book), using a half-mm or so sheet as base, and cladding it with 5 thou sheet with ribs embossed. First I made drawings on paper, transferred to the 5 thou sheet and embossed, like so:

 

QTpzxMo.jpgOn top is the paper drawing, with strut locations marked, below the plastic. The line crossing the sheet will be placed on the leading egde of the wing and the sheet folded over the wing base. After embossing it looks like this:

z3fA1dY.jpg

It is a rather large wing for 1/72 scale.

 

The lower wing and the embossing tool:

 

hYTcsHL.jpg

 

The assembled lower wing pair is shown below. Between the wings only the two spars will remain, positioned above the fuselage above the observer’s cockpit: the observer will take the place of the plastic to be removed.

 

ODcXpu7.jpg

 

Those spars are thin, so I was concerned about the strength. Therefore a metal strip was superglued along the underside, at the location of the spar before wrapping the sheet around:

 

30zpG5I.jpg

 

The metal strip is thin and flexible, so it won’t add much rigidity, but at least it should help preventing fatal wing-breaking accidents.

Edited by Torbjorn
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Thanks for the encouragement :) Closed up the fuselage. I didn’t even try to get it right, figuring it would be easier just to put excessively large pieces and trim them down later. Some serious trimming, patching, putty-ing and sanding to do:

 

tuQMzmX.jpg

 

 

I am considering to try resin casting the struts - it’s twelve of them and all identical. Could that work for a hobby modeller or are struts too thin for this to succeed? I would prefer not to invest in resin and silicone if this plan is futile from the onset.

Edited by Torbjorn
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Hi,

 

Guess it depends on the resin you use as things as small as 1/72 gun barrels can be bought in resin, but the cheapo car repair stuff I use could be a bit brittle for struts . Worth a try I guess. Another problem would be getting the resin into the mould unless it is thin.

 

Pete

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1 hour ago, Courageous said:

I think @Moa has cornered the market with that stuff.

What I still do have, thanks to two extraordinary gentleman (John and Andrew, both of Fogland), is under lock and key in a vault in Antarctica, defended by speakers blasting the Bee Gees (which is an impenetrable wall on itself). Anyone approaching will go mad before even starting.

At the pace I build, I will run out too at some point.

Why nobody does anymore something like Contrail and Strutz airfoiled material?

We modelers should go on strike until we get the products we want.

 

 

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16 hours ago, Moa said:

What I still do have, thanks to two extraordinary gentleman (John and Andrew, both of Fogland), is under lock and key in a vault in Antarctica, defended by speakers blasting the Bee Gees (which is an impenetrable wall on itself). Anyone approaching will go mad before even starting.

At the pace I build, I will run out too at some point.

Why nobody does anymore something like Contrail and Strutz airfoiled material?

We modelers should go on strike until we get the products we want.

 

 

Too sinister for me to dare an intrusion where such evil lurks. But thanks for making me know what I have missed - I had never heard of neither strutz nor contrail. Wonder if it’s possible to shape a thick plastic rod (say 5 mm) and stretch while applying (moderate) heat?  I have another back up plan: partially flattening metal tubes. These struts have a very pronounced taper though, which is why I considered casting - even if I had aerofoil-shaped rod, the tapering process would still take much time.

 

For casting, strength isn’t the issue as in addition to the 12 «normal» struts, there are 8 bare metal struts plus the Λ-strut holding the engine which should be able to carry the wing by themselves. I was more concerned that the dimensions would be so small that it would be too difficult to get them straight and true.

Edited by Torbjorn
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Fortunately I still have the remains of a very old Contrail pack, and when John Adams of Aeroclub was still active a couple of years ago I got a set of Aeroclub strutting from him. I notice he has resurfaced again after what I believe was an illness though I imagine he no longer has any bit and pieces to sell - just glad to see him around again.

 

Cheers

 

Pete

Edited by PeterB
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6 hours ago, Torbjorn said:

Too sinister for me to dare an intrusion where such evil lurks.

An alternative is to wrap plastic (or metal) sheet around a wire or tube creating a teardrop shape. I have done it with good result. I have also, like many modelers, started with a rectangular styrene stick and sanded it into shape, round of course on one end and sanding to a thin edge on the other, using a short length of wood block as support.

 

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On 2/7/2020 at 6:02 PM, Moa said:

An alternative is to wrap plastic (or metal) sheet around a wire or tube creating a teardrop shape. I have done it with good result. I have also, like many modelers, started with a rectangular styrene stick and sanded it into shape, round of course on one end and sanding to a thin edge on the other, using a short length of wood block as support.

 

I tried the wrapping, but couldn’t get consistent results. Maybe it isn’t suitable for the size of these struts. Went for something simple.

1. Take 30 thou plastic rod, cut to length (by accident quite exactly the same as the width of my steel ruler - 21.2 mm - which made it easy to get consistent length. 

2. Squeeze the rod in a vice (half a turn each)

3. taper the ends and sand the trailing edge

 

Left: rod, middle after squeez and right after tapering (one end only as it looks - should be both)

qQMT7IB.jpg

 

 

This was much quicker and gave relatively consistent results:

 

 

dRK8VDQ.jpg

 As you can see the holes in the upper wing aren’t there yet. To get it aligned, a technique out of pre-school will be employed:

 

56ydhxi.jpg

 

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nice work and progress.

 

I work a lot with resin and do my own casting and going down to that size piece,  you really need to go professional with your casting and gear.....vacuum or pressure casting. Plus with those sort of pieces to get it any strength I'd be thin wire to the inside of the struts as the resin is just too brittle, the stuff for fine casting is.

 

It's more time consuming but the plastic as you've done is the way to go.

 

I actually have some Contrail aerofoil strut material........though it does belong to a Contrail Bristol Bombay I hav bin the stash! :D

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Sounds like I was saved from a lot of trouble then. And honestly, you’d need some sort of optics to see that the struts are oval rather then tear-drop in cross-section.

 

And the fuselage is coming along:

 

daqdIjE.jpg

 

The tail will be difficult to get perfectly smooth, but the original was pretty battered too after making patrols (against mines, subs and other unwantwd offenders of neutrality) during the course of the entire war and having several accidents, so I’m not overly concerned. :D 

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I have not been busy, but started on a few things: the tailplane, cut from plastic sheet and suspended on wire (more on that in a later post) and the construction holding the engine. A back plate was made from brass sheet and populated with oil pump, carburettor and air pump, to be glued to a pair of wooden struts and braced by a myriad wires and metal struts.

 

ht5qgwB.jpg

 

 

 

Another high-tech jig was made out of a box formerly containing a Brewster Buffalo kit, so I could get a look of the plane, to see if I’m heading in the right direction.

 

w8ZrqN1.jpg

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On 2/16/2020 at 12:42 PM, MarkSH said:

This is great stuff, Mr Woodman himself would be pleased with the work and problem solving.

Thanks Hewy, Mark.

Woodman’s book is what inspired me to get me into this mess, so I certainly hope he would be :)

 

Completed (almost) the tailplane. As indicated before, it is suspended on 5 ”sticks” above the fuselage, see e.g. here:

 

http://www.natureandtech.com/?p=685

 

The Danish version in the link above appears to have an identical layout of the tailplanes, and these images have greatly helped.


I cut .5 mm (or so) plastic stock to shape, but before cutting I marked the ribs with a pen. The marking does two 

things: 1) making the shaping much easier to cut, especially to get the horizontal stabilizer symmetrical. This is like pre-school, where we were painting a grid over some picture and copied the contents grid by grid. Secondly I hope that by painting thin layers the ribs will shine through the paint so I don’t have to do any annoying masking.

 

The little metal tripods on elevator and rudder that the control wires are to be attached to were made with wire/rod. I drilled holes and connected two pieces as shown below: this gets them symmetrically positioned and improves strength - much less likely to knock one off when attached like this.

 

Tnydps0.jpg

 

The rudder, shown above, contains a conundrum for me. The Swedish air force started out like the British: a merger of the previously separate naval and army air corps. This merger happened almost a decade after this machine was retired. The Flying fish was a naval machine, and as such sported the three-forked naval ensign on the rudder. No decals for that, so I need to paint it. I settled on this approach: spray yellow, mask the cross. That is the current state. Paint the linen-colour, then mask and spray the blue (the forks are easier to mask ”negatively”, or mask the outside especially if the middle fork is already masked). 

 

The rudder was glued to the fin and the. those two to the stabilizer/elevator. The fin is surrounded by a .4 mm wire (yes, it should stick up like that on the top), CA-glued. Tamiya green holds the fin and rudder to the stabiliser. Hopefully this is strong enough. More struts and bracing wire will be added after painting. I drilled holes in the hull for attaching the whole shebang. So far dry-fitted only: 

I066RIq.jpg

 

 

 

Edited by Torbjorn
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