James May Steals My Thunder

I know the first rule of flight club is that you don’t talk about flight club, but I thought it was worth a quick mention despite that.

Not sure what I’m talking about? Well, that means you missed the 2012 Christmas edition of James May’s Toy Stories, entitled ‘Flight Club’. Following on from his 1:1 scale ‘Airfix’ Spitfire, he decided that he wanted to break an aviation record and aimed to break the longest flight of a toy aeroplane. (Here’s the episode on iPlayer.)

Brad Pitt dresses up as his idol

For those of you who have been following my balsa builds, this is an extreme example of exactly what I am trying to achieve. He has inspired me somewhat, and while I do my next couple of balsa builds, I am also going to start working my way through a very interesting-looking book, ‘Aircraft Workshop: Learn To Make Models That Fly’ by Kelvin Shacklock, which starts with a very simple balsa glider (much like those James May has at the beginning of ‘Flight Club’) and works its way up to a very large remote controlled Spitfire. Hopefully by working from the very simplest gliders up to the more complicated rubber-powered planes and beyond, I will understand better what I’m doing and why. And then I’ll be flinging gliders across the channel!

Balsa Wood Mustang, part 4

After some fairly ineffectual faffing about, I decided that the only sensible way to repair the minor damage to the tail would be to brace it with some scrap balsa on the outside of the fuselage, and take the undesirable weight gain on the chin. Below is a picture of my solution to the problem.

Obviously, this could incur some sort of weight penalty and negatively affect the flying performance of the model. However, recent browsing of the Guillow’s forum suggests that the 900 series models (of which which this is one) are designed very light anyway so adding a little extra weight isn’t a problem.

After that, all that remained was to ‘dope’ the wings, and put it all together!

Afterwards, it looked something like this:

WP_000259WP_000258

I’m rather pleased with the attachment of the canopy, even though it won’t be particularly clear from the photos. In the past, I have had problems with clear parts fogging up from glue fumes and was more than a little apprehensive this time. However, carefully tacking down the canopy in the corners with superglue and allowing it to dry before running a tiny amount down the edges seems to have worked a treat. Hopefully it’s all down to technique rather than good fortune!

Aside from that, it’s a pretty ugly model of a rather attractive aeroplane. As you can see, the covering on the wings isn’t as smooth as I was hoping and the glue has left dirty stains on the tissue covering. Hopefully, it will be a triumph of function over form.

At this point, it still needs a couple of fairings added to the wing roots, and I’m considering giving it a quick coat of silver acrylic paint. That may prove to be a disaster, but I won’t know until I try!

Balsa Wood Mustang, part 3

During the covering of the wings, it became clear that the left wing was better built than the right. (There’s a point on the wing where there are two ribs side by side, and on the left wing they are identical, but on the right one rib rises a millimetre or so above the other towards the trailing edge of the wing.) Hopefully this won’t cause major problems. If it does, there is a solution – namely, strip off the tissue, sand level and re-cover.

After all of this came the shrinking stage. I had already been advised to leave the tail surfaces out of this and simply to seal them with the glue and water.

I shrank the fuselage, but unfortunately the tissue was quite slack in a couple of areas (due to some sloppy covering I expect) and so there are some wrinkles in the tissue even after shrinking.

At this point, things started to go slightly wrong.

Firstly, whilst sealing the tail surfaces, the tissue from either side stuck together. After posing the question on the Guillow’s forum, I was reassured that it won’t affect how the model flies, but it has left dark, translucent patches on the surfaces which mean that even before construction is completed, it looks grubby.

Secondly, after spraying the wings with water in the bathroom, I carried them back to┬áConstruction Central (also known as the spare room) pinned to my cork board. Watching the board carefully so as not to damage the wings, I sat down on the bed…. and also on the tail end of the fuselage. D’oh! Luckily, the fuselage itself was virtually undamaged, but I did manage to break the cocktail sticks I was using as a peg to hold the rubber band motor in place, and also weaken the mounting hole.

However, this was not the end of the problems. Reinforcing the hole with scrap balsa would potentially add too much weight behind the ideal centre of gravity, so I decided to drill myself a new hole a few millimetres away from the old one. I was smart enough to realise that the original hole was placed where it was to benefit from the nearby fuselage former so I decided to place my new hole in a similar position. However, despite measuring carefully, I clearly didn’t do it carefully enough. After drilling the new holes I inserted another cocktail stick only to find that it wasn’t level when viewed from above (one hole was nearer the tail than the other. The problem with this (I think) is that as the tension increased in the rubber band during winding, it would slip to the side nearer the nose and increase the stress on the wood on that side and probably tear a wider peg-mounting hole.

At this point, I feel as though more has gone wrong with this build than with the Hurricane. I’ve certainly made more mistakes. This is pretty frustrating considering that I had set myself the lower target of simply trying to make it fly, rather than look like a beautiful model. It will be quite an achievement to get it all completed and balanced at this rate!

Balsa Wood Mustang, part 2

After a prolonged, enforced break caused by the wire provided for the undercarriage proving too hard to cut, the build is back up and running! A new pair of wire cutters were purchased and the main undercarriage cut to size.

However, after some thought, and reading some forum comments against including the undercarriage on a flying model, I decided against adding the wheels. All that unnecessary delay! However, in the intervening period I had done a fair bit of reading on the subject and so the time wasn’t completely wasted.

With no wheels to prepare, all that remained before covering and final assembly was the sealing of the wood with the 50/50 PVA/water mix used on the Hurricane.

Unfortunately the rudder sustained a small amount of damage during sanding and required some very basic repair work.

After that came the covering. First of all the tail plane:

Then the rudder:

Then I thought about getting a bit clever and attaching the wings part way through the covering process as leaving certain parts exposed would give me easier access to clamp the wings to the fuselage while the glue dried. However, posting this idea on the Guillow’s Model Builders’ forum (yes, they have their own dedicated forum!) was met with general disapproval. Apparently, the wings need to be fixed to a flat surface while they dry after the tissue is sprayed with water to shrink the tissue, otherwise there is a serious risk of the wings warping.

(At this point I should probably clarify that I have decided to use this model as a ‘proof of concept demonstrator’, that is, function is everything . Therefore, the undercarriage has been sacrificed to save weight, and decals will be omitted to reduce the need for preparatory coats on the model for much the same reason. Ultimately, the model may not look like much but it should work as well as it possibly can.)

So, I completely covered the fuselage:

And then made a start on the wings:

Once these are all covered, the tissue will be shrunk and then ‘doped’ (I’ll be using the usual PVA/water mix) before final assembly.