Andy Blackburn

That's not a bad idea, Scotty. Might need to locate it with a couple of short 1/8" pegs...

I've only just seen this post - so sorry for the delay, better late than never! The pilots in the original JP were from Pete's Pilots, but I don't think he does them anymore. I think Real Model Pilots ought to be able to provide some /12 scale RAF pilots, but I guess you've already got it sorted...

We're officially on holiday at the moment but I've managed to get a bit of modelling time. I've been agonising about the nose transparency because although the plastic is about 1/32" thick and the moulding is quite sturdy, it is in rather a vulnerable position. After some lengthy consideration I thought the best thing to do was to just accept that it might sustain damage and just get used to the idea that it might occasionally need replacement. So I've changed the plan again and am going to glue it to the front of F1 which might not be particularly secure, but if it comes off there's a reasonable chance of a clean break which will make replacement much easier. Steve has provided a couple of sets of mouldings, so I've used the slightly imperfect set on the basis that if I make a mess of it, it doesn't matter quite so much; separating the nose transparency required a sturdy knife and careful use of a razor-saw: ... and after a few patient minutes with some wet and dry, used wet, it's just about the right size: That's a view from the bottom, the clear vision panel is offset to starboard (to clear the bombsight, apparently). The Canopy looks OK as well: And the overall effect is, I think, pretty good: The only problem now is that having cut out a dirty great hole for the cockpit, it needs to be filled with something . Representations have been made to the usual quarters and with a bit of luck I won't have to make my own pilot and ejector seat (which I am given to understand is a Martin-Baker Mk 1C). Edited By Andy Blackburn on 07/09/2016 19:57:28

Things are still happening on this build, but one of the perils of having a new motorbike in the summer is that one tends to ride it... I've got the transparencies back from Steve at Vortex, this isn't a particularly clear picture but they don't look too bad at all: The plastic is quite thick (just over 0.9mm at the base, so I suspect it was probably 1+mm before vac-forming) but it looks vaguely promising, going to try fitting it tomorrow. The rest of the structure has got to that point where you apply filler... ...the stuff gets everywhere and it it stops raining later this evening I can start to sand it off. I can also have another go at putting my fingers through the wing skin, I seem to be good at that. Stuff to do before covering is: Fit the nose transparency, needs a small rebate in the planking at F1. Fit the cockpit, cut out the cockpit opening and agonize about how much cockpit detail to leave out. Fit the hatch; I have some 6mm x 2mm magnets from Maplins Er... that's it, I think. I'm sticking with the "non-shrinking dope & lightweight Modelspan" covering process, and I think I'm going to have a go at brush-painting Humbrol enamels, if I can get some decals of the right size I'll use them otherwise it might have to be multiple discs of Solartrim in the time-honoured manner.

Top job with the vac former! Do you know what you're going to use to seal the decals with? Some sort of acrylic spray varnish, I'm guessing? And, since not all printer ink is created equal, can I ruthlessly ask what sort of printer you have, please?

> I can understand that on a lightweight open structure, excessive shrinkage is a real problem. For covering solid sheet though, like a fuselage, is it still a problem ? It can be, particularly if the sheet is thin or the wood is soft; a lot of film-covered ARTFs have this problem if you squint a bit and look along the fuselage. > Question 2: I've found that compared to dope, using acrylic varnish on tissue makes it much more 'stretchy' and easier to get round gentle curves. Well, that depends - if you're putting it on dry with dope or acrylic varnish then the water in the varnish will expand the tissue and make it go around compound curves. However, if you do the following then I prefer dope; Apply two or three coats of thinned non-shrinking dope or (preferably) sanding sealer, sanding after each coat. Dampen the tissue and lay it on wet, smooth everything out, stretch around compound curves. Flood thinner through the tissue to attach it to the surface whilst the tissue is still wet. Let everything dry. Two or three coats of thinned non-shrinking dope or (preferably) sanding sealer again, sanding after each coat. Jap tissue needs less dope to fill the weave but it has its own issues.

Looks very good, that does!

> The tightness of the tissues on the frames do look different and when working with such small dimensions the difference could be massive. Well, you say this, but the way it was done was: Lay the frames on the bench carefully Tape the tissue to the bench on one side Attach some tape to the other side, tug carefully and attach to the bench Repeat for the other frame, using the same amount of "tug" So at the very least, the tension is similar.

PM sent.

So, with the canopy and nose transparency formers packed off to Steve, I can start to think about finishing & covering; I'm going to use tissue/sanding sealer/dope because film is just too fragile, and I think this approach might be less work (although more waiting around) than glass+epoxy. I thought about glass+acrylic varnish but I've put a line through that for the following reasons: Acrylic varnish shrinks about as much as full-strength dope. It's water-based so, unlike dope or epoxy, it raises the wood grain which requires a lot of primer. To get the same dead-smooth finish as epoxy, it seems to be a bit heavier. There are four types of tissue available to me at the moment; Peck-Polymers and Sams tissue come in multiple colours but have no wet-strength, so pulling them around compound curves (fuselage, nacelles, wingtips, etc.) isn't going to work. I have a lot of Japanese tissue in various colours, and a few sheets of white "modern" lightweight modelspan, which is very similar to the old stuff but has a slight grain - a bit like the Silkspan that you used to get in Sterling rubber-powered scale kits, but without the wrinkles. I don't want a starved-horse appearance to the structure so the questions are, which of the two candidates shrinks more, and is that shrinkage more with or across the grain? (Yawn - do stay with me, I think it's worth it) So I made a couple of 100mm square frames from 1/16" square balsa, all stripped from the same sheet of wood, and carefully covered with tissue to exactly the same tension, as near as I could get it: then loaded them with the same amount of water: - and look what's happened when they dried: - they've both shrunk, but the Jap tissue has shrunk a lot more. That might explain why my indoor scale models keep warping! After a couple of coats of 50:50 non-shrinking dope/thinners and left overnight, they've both stabilised a bit but the Jap tissue has still shrunk a lot more: - it's quite a lot of shrink: I spent some time trying to come up with a new name for the relative units of shrinkage, such as Relative Uniform Normalised Tension (RUNT) units, but then unfortunately realised that they were 100mm squares so a 1mm shrinkage is 1%. Drat. The numbers are: New Modelspan Shrinkage with the grain: 0.3% [note 1] Shrinkage across the grain: 0.6% Jap Tissue Shrinkage with the grain: 0.3% Shrinkage across the grain: 2.5% (!!!)   That was a bit of a surprise.   Notes 1. I can hear certain parties complaining now about the accuracy of measurement ( "he can't possibly visually measure to that level of accuracy..." ) ; but you can if you use a straight edge and then find a bit of card or wood that will just fit in the gap, and then measure the card with a micrometer... Edited By Andy Blackburn on 17/08/2016 07:55:01

Nicely finished plug, that! What did you finish it with, I assume it's the same construction as the first plug?

Well, I've kinda finished the nose transparency - or at least, it's as close as it's going to get! Here's the general view: and a detail view showing the flat clear vision panel, offset to the right (to clear the bombsight, apparently): I just need to carefully slice this off (it's only tacked on) extend the base a bit because it'll be recessed into the nose sheeting to a depth of about 1/8" and pack it off to Steve at Vortex. Edited By Andy Blackburn on 13/08/2016 18:28:18