Wings of Intent: March 2020

(To see the completed model please go here:

https://wingsofintent.blogspot.com/2020/04/sopwith-bat-boat-172nd-modified.html

Continuing with the modeling saga of less-known types, that nonetheless made significant contributions to aviation history and development, not to mention aesthetics, here is the Sopwith Bat Boat of 1913, credited as the first successful amphibian built in the UK.

Thomas Sopwith came from the boating field, and used in the Bat Boat a type of construction technique called consuta: https://en.wikipedia.org/wiki/Consuta

The Bat Boat design went through several incarnations. The model here represents the plane as it won the Mortimer-Singer amphibian competition of 1913, with retractable landing gear.

Photos show that the plane in this configuration had an inline engine, the fore plane removed, twin rudders under the horizontal tail, and canvas fairing on the space between lower plane and fuselage.

Photos show other versions with what looks like a rotary engine, different radiators, different tails and other changes.

Beware that some plans out there mix features of them all, and are in general suspicious, therefore always rely on photos and compare them with the plans.

There are, as far as I know, two 1/72 kits of this plane, the Joystick vacuum-formed I am using and a Luedemann resin kit, that to my eyes looks just a wee-bit chunky and an itsy-bitsy heavy-handed.

I got this kit thanks to the good offices of fellow modeler L. Santos, who saw it in shop and called me to see if I wanted it (you already know the answer), thanks, L.!

For those unfamiliar with this brand, you get the usual vac sheets, but also white metal parts and airfoiled struts material, both facilitating building greatly. In this case rods to build the frames that support the tail were also included.

The kit came to me started. The vac sheets have been primed, the wings separated (but not cleaned or thinned), and the fuselage sides where already cut and given some reinforcement tabs typical of what we vac builders use. I do not particularly appreciate started kits, but what little it was done to this kit was ok, so I set to continue the build.

The kit allows for different versions to be built. The metal parts consist of engine, fuel tank (so-so), prop (very poor) and wheels (inaccurate, solid ones). The vac floats are better replaced with a plastic rod and cones or similar, since they are not particularly good.

The kit as I got it:

The previous owner cut the wings off, then looked at them, said "hum.." and went for a Martini.
And never came back:

Better now:

Tail elements are excised, the plastic has a good thickness and is forgiving, and not brittle, which is great:

This is here as a guide, not to use:

The fuselage as I got it:

Now carving the opening:

Ready:

The white metal is too soft, the casting poor, and all parts have some degree of mold mismatch:

After cleaning, still not good:

To the right, one form my spares bin that I modified (Aeroclub):

Fuel tank, not good, wheels, inaccurate (solid and generic, the real thing had fatter tires and spokes):

The engine may make it to the model:

New wheels being made:

Now a replacement fuel tank:

And another:

The tail after separation:

Some sanding and float halves glued together:

Have to remove those pips that are part of most vacs:

Better now:

Control surfaces separation lines engraved on the other side:

A third fuel tank, better proportioned and sized:

The rod provided is ok (for the tail riggers) but the strut material is useless for wings, being dismally flimsy:

The wing floats are being replaced:

Now, if you are a newcomer to the vac universe (well, the field is quite smaller than the universe, to be frank. One could say " vac galaxy", may be... but actually "vac world" would be more accurate. You know what, let's go for "small field") you may be asking yourself:
"-What the builder does in this cases of just one surface wings?".
There are several answers to that legitimate question:
1) Ignore it. Only modeling perverts and modeling voyeurs try to look underneath a model
2) Use another, very thin sheet where you have previously engraved the ribs -ribs underneath tend to be very faint, unlike upper-side ribs, which are more showy, so to speak. Like if they were coming from the financial district or something, the little basterds.
But his method usually results in undesirable thickness.
3) Engrave the ribs with a tool on the surface...
Ladies and gentlemen, I give you (trumpets blow, drum roll....)
The Double Engraver ™ !!!
A tool useful for the gentleman as well as for the lady, for the children and the elder (who shan't, under any circumstance, use it), for the office, home, garage, basement, bunker, boat, motor-home, camping, space travel, time travel, to defend yourself against Martians, the tax man, and a thousand more uses!
Only today, at the incredible price of... NOTHING!
You can build one yourself!
Just put two (yes, TWO) blades on your Olfa cutter, perfectly aligned, and you will be making not just one, but TWO, perfectly parallel engraved lines AT THE SAME TIME!
Need more space between them? put a ..... SPACER! yes, another revolutionary invention!

The seats (nothing wrong with them) are replaced by P.E. ones. A "board" floor is prepared:

The prop is painted:

The position of the ribs is determined and marked under the flying surfaces:

And the ribs engraved with the Double Engraver ™:

All surfaces same treatment

The lower wing comes with the strut positions marked, but you need to the do the same underneath the upper wing:

The proto-floats are given their Milliput provisional cones. Once set, they will be trimmed back and refined:

A number of bulkheads are fabricated:

And eventually installed. They will help with rigidity and shape:

A steering wheel is mounted on a column, the seats are prepared to be painted together with the floor and interior. Additional tabs are glued on the hull:

Dry run of the hull. All seems good:

For those of you having this kit and one of the incarnations of the Hansa Brandenburg, the horizontal tail is not far off, but both require work one way or the other:

I am using the vac sheet as a jig. The rod provided is inconsistent in diameter and of course not particularly straight. So this is more a divertimento than a serious approach, but could work.
I also have a backup plan of aluminium/brass/nickel alloy tubes in case results prove disappointing:

The two frames are built:

The future dashboard will have the usual instruments and controls:
1) Tea dispenser
2) Milk dispenser
3) Sugar dispenser
4) Sandwich type selector
5) Scones retractable rack
6) Clotted cream-on-top / Jam-on-top switch
7) Fog level indicator
8) Imperio-Meter (shows which countries/territories the Empire is loosing or gaining at the moment)
9) Mnemotechnic scrolling list of names of relatives (wife, progeny) and club members (the old memory is not what it used to be)
10) Bell to summon Jarvis to the water to park the Bat Boat

Yes, the two frames coincide pretty well:

Et voilà, the new wing floats:

Interior in preparation:

Houston (Calshot? Croydon?), we have a problem...
Why is that many kit manufacturers have photophobia?, that is, the paralyzing terror that impedes them to look at photographs of the type they are producing?
Well, I can look at photos. They show that the leading edge cut out is only above the cockpit opening, and that the struts in that area should be aligned with the others:

Therefore the area has to be filled with styrene and then treated to match the surroundings.
Ts-ts. Mr. Archer...
The cut out on the trailing edge seems (although I do not have a good photo of this specific configuration showing the area) to be ok:

The area that needs correction is packed with styrene:

The joints are given a coat of styrene goo:

A first coat of primer:

The other side of the flying surfaces is primed, revealing still some work to do. Wing floats get a black base for the metal color, as well as the engine and fuel tanks. Seats are painted:

The primer revealed that the molding pips were still mostly there (one of the functions of primer) so sanding paper was wrapped on thin slat of wood in order to access the space between the ribs:

Both wings are tidied:

The interior is located, and the fuselage halves may be joined soon:

The missing positions for the central pairs of struts are measured and marked:

The fuselage halves are united:

Some color is applied:

A sort of improvised simple jig was used to build a resemblance of the radiators:

The radiators will be painted in the next airbrushing session:

The strut material that came with the kit was way too flimsy. From stock that came with another kit (most likely the HP42) I made the necessary 12 struts.
I selected plastic over my usual choice, brass Strutz, because plastic is far easier to shape when the struts are not just straight uniform sections:

The measurements for the tail rig structure are transferred on paper, and joining of the already made sides begins. As I commented before, the rod provided is neither a paradigm of straightness nor of uniform section, but I think it'll do. Of course I do have the normal, readily available white styrene rod, but sometimes for the sake of challenge and to keep close to what may have been an original build up, I use the kit's parts, unless they are frankly bad. You can tell that in spite of fabricating my own wing floats, I also built the kit's, to prove it can be done:

Only the three last sections had cross-members:

The hull is ready for a coat of primer, after joining the halves, puttying and sanding:

A slight course adjustment: the four central struts actually go trough the lower wing center section and anchor on the hull. Therefore, for the sake of rigidity, those are made now of brass Strutz:

A bit of airbrushing. A few more sessions will be needed:

Metal horns are inserted where corresponding before painting is completed:

The other side of the flying surfaces and struts are airbrushed, and the radiators are given their color:

A rough sketch of the frame inside which the engine should go:

And we run into another snag. The only white metal part that seemed usable, the engine, is not the one required here. It doesn't resemble any of the engines used by the Bat Boat, and considering that it had a water radiator, what are those cylinder fins doing there:

The engine used for the Mortimer Singer competition had to be British, so a Green E.6 was installed. This engine had encased cylinders for the water to cool them.
Therefore I have to discard the kit part and most likely fabricate a Green E.6.
I was able to find a Wikipedia image of it, but just of one side. Hours or research online and in within my files, and I still can't find an image of the other side.
To make things better, the Flight Magazine archives (a place where it could most likely be found) are being revamped and offline.
Sigh....
A new engine is fabricated (thanks Adrian for the engine image!) and it's ready for some paint:

The jig used on the Sea Lion was adapted for the Bat Boat.
The plan is to mount the upper wing, then the tail rig structure to the wings, and after that the tail feathers.
That sub-assembly will be glued to the hull, and then the engine, it's struts, the fuel tank and the radiators will be added.
Last would be the landing gear, the hull-to-engine-bearers struts, and details.
(all this sounds very good in my head, we'll see what reality, that tends to be sometimes not very agreeable, dictates)

The plan, checked against photos, showed that some corrections were needed.
Besides the above-mentioned rectification of the lower wing leading edge cut-out, the geometry of the landing gear struts needs tweaking so:

The wings are now united:

The engine is given a black base:

The rig is prepared for the time when the tail booms will be added (that's just a trial dry run).
It was decided to first install the engine, fuel tank and radiators, to have unimpeded access, and then glue the tail booms:

It was decided to glue the tail feathers at this stage, to help with alignment at the moment of gluing the tail booms to the wings.
In the background, to the right, the engine bearers-cum-struts can be seen:

The exhaust is added to the engine.
Do not forget that this plane had a pusher configuration, thus the exhaust has to point towards the prop:

Slight change of plans. The tail unit is added to the wings using the jig. Then removed after the glue had set. The engine bearers are added:

Locations on the hull for the struts are marked and drilled. A last coat of primer is applied.
The engine, already painted black, is given a mist of metal color, in preparation for detail hand painting:

Engine and radiators in place:

Better add the prop now before rigging starts:

Rigging starts trying to follow a sequence that won't hinder the next set of wires, which is not always easy:

Finally the tail boom structure is completed:

The hull is given a coat of a base color with acrylic, in order to proceed with the oil washes that hopefully will render a varnished dark wood effect:

Wing rigging now done too:

Work on the hull to obtain a wood effect proceeds:

Now the planning bottom (it's one side at the time with oil):

All sides of the hull are now treated.
After the oil dries, a coat of varnish will be applied:

A very loose dry run to see how things may look:

The wing floats are given their anchoring struts. Written accounts state they were made of copper, and had a bicycle valve to inflate them back to shape in case of bumps:

There is another chapter of the rigging: the control leads to tail and ailerons.
I am fabricating "pulleys" to install where needed:

The plane at some point received a linen fairing of the area between the lower wing and the hull, visible in photos. For that purpose a thin translucent plastic will be used. This is a recycled scrap, but similar plastics can be found at craft stores:

The retractable landing gear parts are being readied:

and installed:

Nice rainbow this morning:

After not little huffing and puffing, the hull is added, and also all the control leads to the 14 control horns:

Still to go: two struts, some additional rigging, and the wing floats...

Almost there... may be tomorrow I can add the last touches and take photos, if weather allows:

The fabric that was added for the Mortimer Singer competition is attached in form of translucent plastic.
Here a few images as a teaser, with not very good light at this time and stormy skies: