403 Spitfire

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My first Guillows build.

I've attempted a couple of West wings kits a couple of years ago, but never finished them.

I built a Aerographics Curtiss Jenny (badly) before starting the Spit to "get my hand in".

And I lurked here a lot.

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I know the table's pretty flat (it's cast concrete), so holding the frame down with magnets should keep it square

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Holding the formers upright with magnets worked, but wasn't ideal.

I think I'll have to invest the time to make a better solution for my next model.

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Read the plans again!

The instructions are not bad, but can catch first timers (like me!) out. I didn't study the drawing closely enough, and misplaced the peg mount.

I butted it up to the horizontal rib? keel? thinking it would be stronger, but now it's placed to low for the rubber motor run, so I'll have to move it.

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One of the kit's I tried earlier and gave up on was a Spit, and one of the hardest things with that was the wing fillets.

I'm still not sure how I'm going to tackle them when the time comes, but I was pleased the wing openings pulled nicely in to the fuselage with out needing to be soaked or steamed or anything complex.

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Here I'm trying to keep things square once both sides of the fuselage are being built up.

It worked, but it's "magnet expensive".

I wonder how much it would cost to get some nice square solid steel blocks made.

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I'm not 100% convinced with this "precision beam" style of fuselage over the more traditional "box and former" style, but at least it means I can use the "magnet clamp" idea in two axis:

[al]

I like your "Magnet clams." I don;t know if they are better than real "squares," but use what you have. It looks good so far.

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I've been very unsure how to handle the nose cone.

Looking back, I could have made life a lot more simple, but that's experience

My aims were threefold:

Robust. As far as I can gather from the planes/instructions, it should be edge glues to the out line of formers F1. As I expect plenty of nose first landings, this didn't seem a long term solution.

Demountable, so that I can use a winder.

Adjustable, I've a lot to learn about trimming.

The nose cone/former fit isn't perfect stock.

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The plans call for the balancing clay to be added to the nose cone, so another reason for making it demountable.

The kit comes with a vinyl firewall for motor mounting.

I sanded it down until it fitted in the nose cone and then cut and sanded the centre out of it to make a mounting flange for the nose cone:

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I predrilled the pin holes, and pushed them in from the "wrong" (front) side, covered the pin heads with felt tip pen and offered up the cone to push the pins home, there by marking the flange for drilling:

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Then I took the pins out, pushed them in from the back of F1, and glued them in place.



By pure luck, my smallest drill gave a perfect interference fit when I driled the mounting flange to accept the pins:

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So now I can adjust the nose cone easily with respect to proper weighting for CG, and I can effect thrust line changes by shimming the mounting flange. I plan on cutting some washers out of beer can for shims.

I found cutting and preparing the plastic parts quite nerve wracking and difficult, it's so easy to cut off line with a slip of the knife, but I'm pleased so far.

I wasn't sure how to mount the spinner, so first I made sure the prop was fully home in the running position:



And then I spaced the spinner with scrap packing from the nose cone, sellotaped it down as tight as I could and superglued it to the prop.

It worked, and the end result is cleaner than I'd hoped, but I haven't spun it yet to see if it's truly centred, and I'm sure there's a more accurate way.

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It took me a couple of tries to get the tail end stringers nicely parallel and a good fit on the stabiliser.

I'd didn't at first appreciate how accurately they need to be mounted as they form the mounting slot for the tail plane.

Even so, I'm still a bit dubious of their strength once I start jamming packing wedges under the tail in the trimming flights, and I may rebuild them as solid fillets.

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So it's on to the wings.

I haven't tried this type of wing construction before.

I'd like to add a bit of washout on the wing tips, but I suspect I'll have to build the wings flat and then "warp" a bit of washout in with the last few ribs and stringers, as the trailing edge isn't a solid beam and will need support from the structure before twinsting in the washout angle.