Swappable Bf-109 F (prototype build)

[robobob]

Swappable Bf-109 F (Plans currrently in progress)

So this weekend I decided to do a scratchbuild. This is about as scratchy as a scratchbuild could get, and by that I mean me messing around with foamboard (and burning myself with hot glue) over a weekend.







I have started building a working prototype model of a BF 109 F-4. The main goal of this prototype model was mainly to understand construction techniques for drawing up plans for a more finalized model. As far as I can tell, so far this has been a success: I have learned plenty from this experience and also begun to establish what does and doesn't work so well.

For example, I am almost fully satisfied with the result of the back section of the aircraft, but the front section does not quite look good enough for my standards and I will be experimenting with more build techniques this week, trying to get that more "messerschmitt" kind of nose, that helps to define the very sleek profile of the bf 109.

As for something crucial that I have learned: Multi fold leading edge wings are next to damn impossible to produce so that they are symmetrical. so now I know, stick to one face along the leading edge, one for the horizontal surface, and one to the face toward the trailing edge.
(As a question to the more seasoned scratch builders, does anyone know a good way of getting a multi fold along the leading edge to be symmetrical, or should one just not bother?)

As for now, the prototype build is not yet complete, however she does glide well across my bedroom, which puts me in good hopes that powered flight will be a success. I have already started designing the plans on adobe illustrator (using a free trial) for the improved model making adjustments where necessary to improve the overall design. Do let me know if this plane looks like something you people would want to have in your fleet, because if so I will try and post completed usable plans on this thread. Following up on my thread with the idea of twitch streaming scratchbuilds, once the plans are complete I might consider doing a twitch stream of building it to the plans that I have drawn up so that anyone else wishing to build it can follow along.

 

[JimCR120]

Very nice. Looking forward to the progress and the posts.

 

[DamoRC]

Looking good robobob!

On the multi-fold wing question, it's definitely tricky, but doable. I think a lot depends on (1) making sure the wing panel is cut exactly with the LE score cut evenly dividing the panel (2) evenly cut bevels for the LE, which influences the way the wing wants to fold. During assembly then, having glued in a spar to one surface of the wing, its a matter of ensuring that when you fold over the other surface of the wing that the TE of each panel are flush. Pulling the LE upward with your fingers while keeping the palms of your hands on the spar to hold it down helps curl it over.

In your case however, it looks like this is going to be tricky based on the direction of the fold. It seems like you have the spar running all the way to the LE at the wing tips?

Another option that I like to use is to not use score cuts, but remove the paper from the wing panels from the spar to the LE. I then fold the wing 100% ensuring the the TEs line up (training the LE bevel to fold correctly). This works reasonably well on larger chord wings (hard to do on small wings, particularly with the new white foamboard as it seems to be less inclined to bend easily when the paper is removed).

DamoRC

 

[robobob]

Free plans being drawn!

So, over the past week, I've been working hard to draw up some free plans *trying to get them done before my adobe illustrator trial runs out* and I've hit an important design question, which I'd love some outside feedback on. Where should I mount the two rear servos?

I could mount the two servos inside the aircraft like so:




toward the forward section of the aircraft, and have control rods running all the way back to the control surfaces at the back....


Or I could have them how they are now, which is like this:


I'd love to know anyone's opinion on this, as personally I feel the new configuration would be much better aesthetically, but I'm unsure as to what other implications it would have controls wise...

(As a side note, The plans should be available with any luck by tomorrow, I've designed it so that they will work for both american modellers with the 4mm adams readiboard, and British modellers like myself who are stuck with the 3mm and 5mm stuff. There will be a key on the plans explaining which differently coloured lines to follow based on whether you are working with 3/5mm or 4mm foamboard.)