David lovegrove
A while ago, a few members of the Committee were tasked with devising a proposal for a Club Group Build to take place later this year. I’m sure you’ll remember last year’s highly successful Foamie Challenge which was a lot of fun and produced several original designs. This suggested a great place to start.
Cheap and cheerful wallfoam is a such a useful medium for experimentation that it seemed almost perverse to ignore its possibilities. And the chances are that many of you will have plenty left over from the rolls you bought, just begging to be used up!
This time though, instead of allowing free rein to concoct/design your own flying(?) model, the guys are asking you to work with the idea of a ‘cartoon-scale’ WW2 fighter. The choice of subjects is huge – Axis or Allied, USAF, RAF, French, German, Russian or whatever takes your fancy. And don’t forget those radical ‘conceptual’ German and Japanese fighters towards the end of WW2, few of which ever got further than the drawing board.
These now-iconic aircraft will lend themselves well to rendition in wallfoam. The only missing ingredient is your imagination. The simple rules appear in the full list below.
The finish is your choice: bare white foam or a full camo scheme – it’s up to you. The main aim is to demonstrate airworthiness. But if you do go to the trouble of a full ‘camo’ scheme, your enterprise will certainly be rewarded. And you never know; your masterpiece could end up reproduced in the hallowed pages of the Aero Modeller!
But, as we’ve said, there will be RULES. Notionally, these are:
The model must represent a genuine WW2 warbird, regardless of whether it ever entered service.
The fuselage can be a simple rectangular section.
The fuselage must be no less than 17 mm wide at its widest point.
“Cartoon” outline shapes are expected and are acceptable.
The plan (hand-drawn is OK) must fit onto one A4 sheet of paper. If there is no plan, then the entrant must demonstrate to the judges that it would be possible to fit the plan onto the specified paper.
The model must use either; The approved propellor (we may be able to supply a few of these), or
A propeller from the previous foamie challenge, or
A scraped plastic propeller (cut down if necessary) of no more than 4” diameter.
At least 50% of the construction must be from wall Insulation foam.
The more devious amongst you will have spotted that this list contains a few loopholes. In the usual light-hearted spirit of our indoor comps, to add to the fun we’ll reserve one or two prizes for those who can make the best and most imaginative use of them.
To summarise, the event will be similar to last year’s ‘Foamie Design Challenge’, this time focussing on foamie warbirds built as semi-profile, ‘cartoon’ scale models. A lot of you have seen models using this technique flying very well, so you’ll know they’re worth keeping after the event.
Theres a video of the Kawanishi flying here on Youtube at about 1 min in.
We’d like to encourage everyone to come up with their own design, using the construction technique shown on the three example plans shown here. Should inspiration desert you,
well-proven F6F Hellcat design by OMFC member Lionel Haines (thanks Lionel) is a sure-fire flyer.
We’re planning for the September 2024 Club meeting at Begbroke to be an early opportunity to get to grips with the construction techniques and might also involve the opportunity to make a prop (the only really taxing bit) from a kit of parts. ‘Expert’ guidance will be on hand. If time allows, it might also include preparation of the foam pieces and collecting all the other bits and pieces needed.
And to round it all off, a flying evening/mêlée at the January 2025 Begbroke meeting will decide the lucky/wily/skilful winners! Flying will be a simple duration event, flying points will the usual Total of Three Flights. Time to start researching your winning entry!…
How to Design Your Own Foamie Warbird – Andy Blackburn
Having designed a couple of foamie warbirds I thought it might be a nice idea to write a few words on how it’s done – it really is very straightforward, and the outlines don’t have to be dead accurate, all we’re looking for is something that captures the essence pf the real aircraft.
All this started with a one-model event for Lionel Haines’ foamie F6F Hellcat that was held at Trinity some years ago; however, it was a one-model competition so I thought it might be quite amusing to try and subvert the proceedings…
Kawanishi N1-K “George”
In WW2 the real F6F was sometimes confused with the Kawanishi N1-K “George”, so I evolved a devious plan:
A fullsize PDF of the plan can be downloaded here
First, draw up a copy of Lionel’s F6F plan with the outlines changed to represent a Kawanishi “George”
Second, build the model and swear blind that it was built from Lionel’s plan, just not very well (impossible to disprove).
Finally, finish the model in an Authentic Japanese Navy colour scheme and claim that it represented an F6F Hellcat that had been captured and was undergoing evaluation (also impossible to disprove).
In the event that the model was excluded I was going to make a song and dance about it, with a pre-prepared speech including phrases such as “manifestly unfair” and “travesty of justice”… It would have been interesting to see whether I could have got away with it, but fate intervened, and I didn’t get the model finished. But David Lovegrove has built one and it’s quite impressive.
Hawker Hurricane Mk II
I recently drew up this Hawker Hurricane plan to the same basic principles; as it’s an inline engine with a spinner, it’s a little more complex. But it looks nice, and David is building one (can’t stop himself).
A fullsize PDF of the plan can be downloaded here
Doing It Yourself
Drawing up these things is really easy because you usually don’t need to worry about finding a front view – if built to the A4 sheet size, models always get 20 mm of dihedral each side unless they have a noticeably flat wing (e.g. Hawker Hurricane), in which case they get 12 mm. The fuselage top view is always 17 mm wide, tapering behind the wing. The wall foam itself is a little less than 2 mm thick, I usually use 1.8 mm in TurboCAD and that seems to work OK.
The design process is very simple; assuming that we’re using pencil and paper (experienced CAD users will be familiar with duplicating this process electronically):
1. Choose the Subject
Find a drawing or colour 3-view of a subject that you like; there are loads of scale drawings at https://drawingdatabase.com/category/aircraft/air-force/fighter/ but the drawing below is from the well-known series of books by Kenneth Munson (in this case, “Fighters 1939-45”) originally published by Blandford.
Don’t worry too much about the fin and tailplane sizes because they’ll be enlarged to a decent size anyway – it’s only cartoon scale. Radial-engined aircraft are easier and simpler. Let’s assume that we’re going to do a Nakajima Ki-44 Shoki (drawing on left).
2. Make a Copy to the right Size
Print the drawing, measure the wingspan and then re-print at the correct size – you want a wingspan of about 11” (281 mm) to make it fit onto A4 paper if you’re showing both left and right wings together, so if the span of the drawing is 104 mm, you need to print it out at 281/104 = 2.70x or 270%
3. Trace the Outline and Adjust as Necessary
Tape down the drawing and tape some tracing paper over the top, trace the outlines and any important areas such as the canopy framing, re-positioning the tracing paper as necessary. Stop at this point and have a good look at the tail surfaces – are they a bit small compared to the available plans (Hellcat/N1-K “George”/Hurricane)? If so (as in this case), re-draw the outlines until they look about the same size as the reference designs (you could use the enlargement facility on your scanner). If you’re unsure what to do about the fin, leave it alone. For aircraft such as this Ki-44 which has a titchy tiny fin, enlarge it by 50% of the tailplane enlargement (so if the tailplane was enlarged by say 30%, enlarge the fin by 15%).
4. Add the flying surfaces in Side View
Copy the wing section from one of the existing plans, enlarge/reduce using your copier and add it to the side view, making sure that it has +2.5 degrees incidence. Tailplanes should be set at 0 degrees. The wing might need moving up a little bit so that it doesn’t interfere with the foam sheeting on the bottom of the fuselage.
5. Finish off with Details
Finish off with the top and bottom sheeting, doublers, noseblock, prop assembly, and so on, and you’re almost finished – don’t forget the downthrust. Make up some cardboard templates from a cereal packet for cutting foam to shape, and you’re done.
6. Test flying
This is one model that you must test-glide, because the wing incidence and decalage is already set, so the safest way of getting a good set-up is to test-glide the thing in the living-room. You might find it easier to remove the noseblock and adjust the glide until it floats nicely, then find out where the c.g. is by taping a couple of short lengths of cocktail stick to the wing top surface and balancing it in the fingers upside-down. Then install the rubber and prop and, wind some turns on to stop the motor flopping around and messing things up, pin the prop in place and then balance in the same place. Then you can wind on a few turns and see what it does.