Spitfire Mk1a AR213

[Jessie The Jeep]

Some of you will have seen the 1/5 scale Grumman Tigercat elsewhere on this forum, that I've been building for a customer. This has taken a back seat for now, while the same customers other model is undergoing final detailing and painting in my workshop. Since June last year, I've been working on this four days a week at a friends workshop. Between us we've put in around 1500 hours so far. My workshop is bigger than Phil's, so for the last few weeks, it's been here where there is more space to walk around it while spraying.

 

The model is being based on the only Spitfire Mk1a flying, AR213, based at Booker. Here's a picture of the fullsize at Flying Legends last year. This aircraft has only recently been completed and converted back to its Mk1a status after a six year rebuild.

 

 

The model we are building is 1/4 scale, which means much of the detailing is of a size where it can accurately be reproduced. One area where this is the case was the cockpit fuselage formers, pressed out of aluminium, complete with swaged holes. They needed to be functional, and also scale looking, so we just copied the original blueprints.

 

[Jessie The Jeep]

The fuselage is virtually complete as regards to details, and has had two coats of RAF 'Sky' painted on the underside and around the rear fuselage.

 

 

Unlike most models of this size, it is to be powered by an electric motor. The torque from this motor, which is around 4 inches in diameter, will swing a scale three blade propeller at around 5000rpm.

 

Electric Motor Test

 

While fitting an electric motor might seem a little 'Soul-less' for a Merlin powered aircraft, it allows us to fit a 'Merlin' sound system!

 

See this link for the Sound System Test

[Jessie The Jeep]

Cockpit detailing has been one of the fun bits. Here's the entry door and top of the control column.

 

 

[Tony B]

Ever thought of going 1:1 ? They really are more works of art than enginering.

[Jessie The Jeep]

Here's the instrument panel, which is probably less than 50% of the cockpit detail. Many more items line the cockpit walls.

 

 

The seat is also completely scale, and the lever on the side does actually raise and lower the seat!

 

[Jessie The Jeep]

Ever thought of going 1:1 ?.....

 

No, for me, the interest in flying is controlling the plane, not looking down from on high seeing ants on the ground. Model building means I can be a Spitfire pilot one day, a B-17 pilot the next, and the day after a SR-71 Blackbird pilot. Anything my modelling budget and imagination will allow. If I flew fullsize, unless I hit the lottery big time, I'd be stuck flying the same spam can every outing!

[Tony B]

The old film 'Flight of the Phonix'. when the model aircraft designer first suggests building the aircrfat from bits, the rest poo Hoo him. His answer is ' A model aircraft needs to be designed more carfully than a real one. It must fly on its own. There is no pilot sitting in it to so it has to more stable'. Very true I think.

[Jessie The Jeep]

One of the unusual features of the Spitfire is the flap linkage. In order to get the required travel and angle, the linkage sticks up through the wing when the flap is down. A small door covers this link when the flaps are up. This also gives the pilot a visual indication of the flap position. This has been duplicated on the model.

 

 

Here's a close up of the linkage and flap door.

 

[Jessie The Jeep]

The exhausts are hollowed out resin castings which allow cooling air from the motor to exit the engine cowling. Cooling air enters the chin intake and is ducted forwards to just behind the spinner before being drawn back through the motor.

 

 

Even the underside is fully detailed including inside the wheel wells seen here.

 

[Jessie The Jeep]

Finally todays progress which included adding some of the stencilling on the wing underside and the start of the national insignia.

 

 

[N.O.S.]

So I'm guessing the smaller panel instruments must be about 1/2" dia.? A fair bit of work just detailing these - are the dial face photos of the real thing?

[Jessie The Jeep]

Some of the printed faces were from a MkIX instrument panel kit and were used, the others are photos of original instruments. All the panel and switches are scratch built, and we are awaiting some rub down transfers being made for all the stencilling on the panel. The text in some places is only about 1mm high.

[N.O.S.]

What materials have you used for the fuselage and wing cores and surface, Steve? Must be something pretty light but tough!

[Jessie The Jeep]

The fuselage and wing are fibreglass. They were made ( badly/heavily ) by a guy in Finland who was great at surface detailing, but not that good with fibreglass and who couldn't build straight! After he fell ill through exposure to epoxy resins, he sold the basic mouldings to the current owner who commissioned Phil and myself to complete the model. Much of the 1500 hours has been spent fixing mistakes.

 

We could have done it better, lighter and quicker from scratch, but the owner had already spent quite a bit on buying the mouldings, so we continued. One set of flight batteries for this model cost somewhere in the region of £600 trade price! They are Lithium Polymer batteries running the motor on about 48 volts with the motor pulling almost 200AH flat out.

Edited April 22, 2009 by Jessie The Jeep

[Mark]

Have you a picture of the engine Steve ?

[Jessie The Jeep]

Not at the moment. Phil took it home along with the batteries so he could wire up the second set of batteries with the connectors the same way around.

 

It looks identical to the motors on this page - Hackerbrushless.com, but is much more powerful.

 

Steve

[Enigma]

Very impressive work.

So when will you built a fullscale flying replica?

[Jessie The Jeep]

When somebody pays me to do it! It's a business for me now, not a hobby.

[Jessie The Jeep]

We've made good progress over the last couple of days, with most of the fuselage painting completed. The wing is complete but for three walkway stencils that are having new masks cut, the originals being too small. This is how it all looked a couple of days ago.

 

 

The exhausts were given a brushing with graphite powder, and then polished slightly with a toothbrush to give a slight metallic sheen to them. They were then sprayed with a satin clear coat to seal everything in.

 

[Jessie The Jeep]

Yesterday, all the camouflage was applied to the fuselage. Today, we started applying markings, and the numerous stencils dotted all around the airframe. Various computer cut stencils were used for the paint masks, and in this picture, you can see the national insignia masks, plus the serial number in addition to several small masks part painted.

 

 

To stop paint bleeding under the edges of the masks where they pass over panel lines and rivets, the first coat of paint over the mask is the same as the background colour. This seals down the edges, and means if any paint does bleed, it is the same as the background so when the proper colour is applied, it doesn't bleed.

 

Here's the serial number after the masking is removed.

 

Edited June 18, 2015 by Jessie The Jeep

[Jessie The Jeep]

Here's some more examples of the stencilling. Much of the text is only 1/4 inch tall. The first picture shows three stencils applied to the airframe, and the left two have had their base colour coats applied ( Sky and Dark Green ). The Dark Earth is still to spray.

 

 

Bottom of the tailplane.

 

 

Fuel tank filler cap.

 

[Jessie The Jeep]

Rudder markings.

 

[Jessie The Jeep]

Electrical and Radio Socket. Sprayed, and after masking removal.

 

 

[Jessie The Jeep]

Lastly for today, one of the smallest parts of the model. On top of the rudder is a small mast which holds the aerial fitting. Phil made the aerial fitting the other day, but hadn't done the final job of the fixing. I made the fixing today which consists of a washer and a split pin.

 

What isn't apparent in the picture is that the upright mast that the aerial fitting slides on to is 2mm in diameter. It took around 15 minutes by hand, to drill a 0.3mm hole through this 2mm brass rod, and then make a 4mm long split pin to retain the aerial and washer!

 

 

Steve

[thedawnpatrol]

That really is a fantastic job Steve, well done.

 

It seams like a life time ago that I rebuilt my MKV (full size) but your attention to detail is just like mine was.

 

well done

 

Jules