Take one Dynam Spitfire...

[The Wright Stuff]

Well, having participated in this great forum for a fair while now, and having received lots of great advice from fellow modellers, I thought it was about time I posted something from my own model flying activities.

A health warning before we start: this isn't a traditional build log. I'm well aware that there are many of you out there who wouldn't classify assembling/modifying a foam ATRF kit as a build, and I'd probably agree. However, I'm at the 'thirty-something' stage of life where the free time for pastimes such as this seems to hit a lifetime low. Between work (I travel a lot) and family life, there is usually only an hour or two per week left for modelling, especially if I've nipped down to the flying field for an hour after work! I thought I'd keep some notes from this build as a bit of inspiration for others that might find themselves in the same predicament.

Like many model fliers, I've patiently heeded the advice of what first planes should and shouldn't be, progressed from my trainer onto faster, less stable models, through low wingers and now onto warbirds. I'm also far from alone in wanting a model of Reginald Mitchell's fine creation. One day, I'm sure I'll join the ranks of those with a 72" span model built up lovingly from plans, but for now, a foamie will have to do!

I should also mention that this isn't particularly novel - there are plenty of threads on similar modifications on other (mainly U.S.) forums, but this is my version! Hopefully I can add a few hints and tips of my own along the way! Feedback and comments are of course, very welcome! But please be patient with me!

[The Wright Stuff]

OK, so this is one of my sources of inspiration:

And yes, among the more observant I can sense a furrowing of the eyebrows!

This is my beloved E-Flite Hurricane. It's built stock apart from detailing paintwork (e.g. adding gas-detection patch) and flies beautifully: a foamie but a with a wing loading that makes you work at it a bit.

So the inspiration bit is about a foot to the right of the Hurricane. To paraphrase Douglas Adams: that space where the Spitfire isn't. The aim of this thread is to create a stablemate for Darkie's Hurricane!

[Tony Bennett]

while not a great lover of the spitfire. ( dons hard hat and takes cover)

i look forward to seeing how yours turns out.

[The Wright Stuff]

So, why the Dynam ARTF?

Well, my Hurricane is a (for me) perfect 53.5 inches span, which is a scale of about 1:9. This basically translates to the biggest size one can get into a typical hatchback without removing the wing. It flies on a 3S pack, of which I have numerous. Hence the brief is something the same (stand-off) scale as the Hurricane, also powered by 3S cells, and with working flaps and retracts. The Dynam Spit at approx 48 inches span worked out to be about the closest I was going to get. Whilst I love the looks of the Parkzone Spitfire, and appreciate it's a high quality model: I just wanted to go that little bit bigger. The larger ARTF Spits start to get into much bigger battery packs, so the Dynam it is. Since the model is a few years old now, there are some good deals about.

The main drawback is the look of the thing. It's a bit... ...well..., blue! Doesn't really have the correct dihedral look during the iconic Spitfire wing over as it turns to face you. Flaps are provided as an option, but they aren't split.

But all that can be fixed! I hope!

[The Wright Stuff]

Having introduced the thread, time for some details.

I've set myself the target of the following modifications. Some are cosmetic, some will affect the way it flies, and some will be purely for my personal preference. I'm not too bothered about keeping it super-light, since the model is quite lightly-loaded out of the box, certainly compared to the Hurricane which weights a whopping 2.2 kg, and I've some experience of flying models with larger wing loadings. However, clearly, any increase in weight will have to be carefully justified, and the wing strengthened as required.

• Modify the wing dihedral to present the correct 6 degrees of dihedral.
• Add working split flaps, installing servos and wiring as required.
• Modify the undercarriage (retracts) to present the correct rake, and hopefully minimise nose-overs.
• Remove the unsightly moulding patterns that litter the model, particularly the lower wing.
• Make covers to hide the servos and wiring gulleys on the wing underside.
• Reinforce the wing at documented weak spots around the cannon.
• Install a correct 1/9 scale pilot.
• Repaint into authentic Dark Sea Grey / Medium Sea Grey / Olive Drab scheme, with D-Day stripes on the lower surfaces only, as appropriate for a Mk IX in the Autumn of 1944 following the D-Day invasion.

This list may be updated as I go along due to changes in motivation!

Edited By The Wright Stuff on 11/08/2014 18:43:02

[Colin Leighfield]

Success is guaranteed, I look forward to seeing the finished result!

[The Wright Stuff]

And this is what I hope it will resemble at the end:

Not my photos I hasten to add!

Thanks for reading so far! Now for me to put my money where my mouth is!!!

[Colin Leighfield]

Well, that's a MkIX with the '"e" wing, so you're on the right track.

[Biggles' Elder Brother - Moderator]

I'm sure that this will be a very interesting thread for a lot of us TWS. I know exactly what you mean about the dire lack of hobby time for thirty-somethings! While that time in my life is a "few" years behind me now I well remember it as a time when work, doing up a house and family seemed to take every waking moment. Sadly for my generation (late fifties) foamie ARTF's didn't exist. There were some ARTF's of course - but they were most certainly not just assemble and fly out of the box! In reality I seem to remember them requiring a significant amount of time!

Because of this many of us "fell by the wayside" and effectively took a few years - like 15 - off from the hobby. Which is a great pity. I think with this idea you really have hit on something - OK its a "fly out of the box" foamie - but when you have finished what is in time terms a realisable project for you it will be YOUR Spitfire! Distinctly different from the others.

And in reality I suspect many of us fly a mixture. I'm still working full-time in a pretty demanding job so while I like to build, if I only flew what I could build in the time available I would not have many models! So I supplement my building with ARTF's and the odd "conversion" and I think in that I'm like many aeromodellers in full time employment. And long may it continue! I really have little time for those retired "men of leisure" who feel that the only "real" aeromodellers are those that start a project by chopping down their own balsa trees!

Anyway - I'll be watching with interest and I'm sure many others will want to pick up a few tips on customising an "off the shelf" scale foamie. More power to your elbow!

BEB

Edited By Biggles' Elder Brother - Moderator on 11/08/2014 19:39:22

[Josip Vrandecic -Mes]

Hi TWS , there is no need to apologize for ARTF, because it is a matter of taste ... and I like your choice because I am away at sixty+something, and I prefer to fly and everything else is secondary. So Spitfire (any) as usual irreplaceable model in the collection of every modeller....

Regards

Jo

[The Wright Stuff]

Thanks for the kind encouragement, all. It feels like I've some pressure to deliver the goods, now!

Colin, many thanks for the inspiration for this - I followed your thread. The full-size photos represent PL344, so the same as the markings supplied with the kit. This is something obvious I could personalise, but actually I think with the serial number I'll just go with the kit version, not least because the stickers supplied are (unlike the paint) pretty good quality in terms of colour and finish...

Edited By The Wright Stuff on 11/08/2014 19:56:38

[Colin Leighfield]

Yes, they are and why not. Don't forget that the retracts on the early ones were a bit unpredictable, perhaps they've improved them now. If not, Eflite's go almost straight in, although a bit pricey.

I've still got mine and it's proved to be durable. Plenty of life in it yet. I'm thinking of clipping the wing-tips and turning it into a LFIX/XVI. I might fit a pointed top to the rudder as well to make it look like a later one.

[Steve Colman]

I will be following this closely and look forward to seeing your progress TWS.

I admit with great shame to not having flown my Dynam Spit at all this year. I did however, prepare her for a return to flying duties this weekend. Now just waiting for the right moment.

My Spit is more or less stock apart from a paint job and a few simple mods here and there. But, I suppose I could get tempted to go a little further after seeing what you achieve TWS.

A couple of pics.

Steve.

[john stones 1 - Moderator]

I admit it, I like wood

Foamie's have brought loads into the hobby and they fly well, what's not to like

John

[Trevor Crook]

I also look forward to seeing this project progress. I've recently bought the Dynam Hurricane, about the same size as the Parkzone one. It flies really well on 4s, and is a pretty fair scale effort. The six-port exhausts are wrong and have been replaced by hand carved balsa ones, and Dynam have unfortunately slotted the wings to allow flaps to be cut out - on the upper surface! I've yet to sort that one.

The Spitfire needs a lot more work, which you look like you've captured in your list. Are you going to modify the u/c so it retracts away from the l/e? That looks the biggest challenge, and I wouldn't blame you if you leave it as it is. Good luck, and post plenty of photos please!

[The Wright Stuff]

Steve, your's looks great. Not sure I can better that! Thanks Trevor, I will have a think about the undercarriage - I've a little way to go before I have to make that decision.

So, the 'stock' photo gives a good overview of where I'm starting from. I didn't fully assemble the kit before my modifications, so I won't have 'before' and 'after' photos of my own for the whole aeroplane. However I did check everything fitted together okay, and (most importantly) checked all the servos, the wiring and the ESC, the hinges and the control surfaces before I started to hack. This is important, since once you modify stuff I imagine it's difficult to exchange it if you subsequently find a manufacturing fault, even with an unrelated part.

This isn't a review of the kit: they are available elsewhere, so I won't give a blow-by-blow account of the routine stuff. In that sense, I'll report by exception: i.e. if something strikes me as being particularly good or particularly bad, I'll comment on it. However, don't let this stop you from asking questions!

I started with the tail assembly, since that's an easy bit to complete, with no major modifications required.

[The Wright Stuff]

The close up photo gives a good idea of the finish: baby blue with curious circular moulding patterns over much of the panels.

I took these off with a sharp scalpel blade (a long one like No. 11 tends to work best). Quite time consuming but it's fairly 'brain-in-neutral' work.

Following on with fine sandpaper or (better) wet/dry paper smooths the surface off. Don't be tempted to just go at it with rough sandpaper: it will tend to rip the foam. Once sanded, it was painted using Humbrol and Revell Acrylic paint:

• Revell 68 (Dark Green): an almost perfect colour match to the existing dark green, incidentally.
• Humbrol 106 (Ocean Grey)
• Humbrol 64 (Light Grey)

The advantage with the acrylics is that they give a tough, slightly elastic finish, dry quickly, innocuous for use on the kitchen table, are safe with foam, and have enough substance to hide the granularity of the underlying foam. It doesn't need to be fuel proof. The trick is to use as large a brush as you can get away with: the paint dries so quickly that you'll need to keep moving. I found that two thin coats works pretty well. Sanding back after the first coat gives a finer finish, since the paint 'sets' the foam in much the same way that sanding sealer does balsa.

Edited By The Wright Stuff on 12/08/2014 18:32:51

[The Wright Stuff]

The horns for the rudder and elevator use moulded pins rather than screws, and seem a snug enough fit. I used plenty of epoxy, allowing it to form a fine bead around the horn moulding base. I painted over the base to reduce the visual impact a little. There's really not much more to say about this: the stickers adhere well (get them in the right place first time - they won't come off again without bringing the paint with them).

[The Wright Stuff]

Next up is the wing, which encompasses most of my planned mods, so is going to be a fairly big task. A crude comparison of the model wing underside to that of a drawing of the full size looks something like this:

The overall shape of the wing is pretty close: the aileron and flap positions are accurate. The main deviations are the position and angle of the wheel wells, and the positions of the radiators: they are too far apart.

I had a good long look at the model last night, and I've decided to leave the wheel wells substantially where they are. The 'correct' positions are through where the glass fibre main spars go, and moving those around is quite a big, structurally disruptive, task. While probably soluble, it's a bit beyond the scope of this project. However, I'll relieve the wells when I rake the undercarriage forward, which will change the angle a little bit. I also hope the invasion stripes will break up the shapes somewhat, meaning it's a bit less obvious.

I'm committed to the concept of split flaps, and toying with the idea of also adding the inboard sections, too. The E-Flite Hurricane achieves this by using 'Y' shaped pushrods to operate each section. This won't work here because the servos are mounted towards the outboard section of each flap, but coming up with a suitable mechanical linkage, similar to that in the full size Spit, ought to be interesting.

Edited By The Wright Stuff on 14/08/2014 18:04:03

[The Wright Stuff]

Flap servos:

The model is 'flap ready', and while I won't be using the standard flap part-cut-outs in the wing, I will make use of the servo pockets cut into the wing. I ordered a couple of 9 g servos from The Internet Model Shop - the DY-1007 model fits the pockets and matches the aileron servos, which (from a 10 minute test, at least) appear to operate precisely and reliably.

The foam blanks pull out of the slots easily enough. Oddly, the two servo pockets are mirror images from one wing to the other, like the aileron servos, presumably because it is cheaper to make it that way. I'd like to have the option to operate both flaps from a single channel using a Y-lead, without using any additional reversal electronics. It's a fairly simple task to modify one of the slots to lie the servo down on its opposite side, so that both of the flap servos will go in the same way around.

Obviously, servo wire extensions are required, and the narrow rectangular tunnel left in the foam wasn't exactly inviting me to thread the plugs and sockets through. Alternative options involving pulling bits of string through, or opening up channels with a knife weren't appealing. I prefer to solder the extension wires to the servo leads, so by far the easiest way to thread the wiring is to push through the ribbon cable before soldering to the servo.

Cutting off the plug from the extension cable leaves a rigid wire: straightforward to thread:

[Colin Leighfield]

Keep going! Although non-scale, it's probably wise to leave the undercarriage where it is for practical reasons, but raking forward slightly makes it look a lot more realistic as well as being safer in landings!

Edited By Colin Leighfield on 14/08/2014 19:25:28

[Steve Colman]

+1 on raking the undercarriage forward. Even with the mod the model is still prone to nose overs on landing if you have a grass strip.

[John L]

Just ordered this model and awaiting delivery. Already have the acrylic paint waiting --- Tamiya. Used this paint to convert my Hurricane JX-B to a Sea Hurricane, 7-L ( preserved at Old Warden) This plane flew from HMS Indomitable in WW2 when my Dad served on the Malta Convoy Pedestal 1942. Carrier was badly damaged by bombs so he moved on to the Russian Convoys on Corvettes!!

The replacement pilot is ready ( what were they thinking of? ). Going to follow this thread with interest as I start my own mods. By the way, got through the thirties, forties, fifties too busy to model and now retired -- ah bliss, moved on so far from my younger days, and foamies are so much easier to repair!!!!

Good luck with the build.

[Colin Leighfield]

Although this is from an earlier thread, here's mine!

[Trevor Crook]

I think you've made the right call on the u/c. As long as it looks roughly right when it's down, you will hardly notice it when it is up. Getting the dihedral angle right will improve the overall look much more.