The Warbirds Replicas Macchi C.202 is Landing!

[Brian Seymour]

Cheers Dwain, the planking wasn't all that bad really... although it's much easier to say now that it's done!

[Paul Johnson 4]

Brian..

lost for words mate..... so good!

MMMm hang on a second.... !!!!Brian!!!! AAHHAA.... it's the messiah or just a naughty naughty boy?

[Brian Seymour]

Cheers Paul, not sure about the Messiah and now that I'm over 25 I don't get much chance to get naughty!

The wing fairing took more head-scratching than actually doing. The fairing on this model is a quite big so I didn't want to hewn it from solid balsa. The 2015 model was a bit of a hash which turned out nicely but used a fair bit of filler so I reckoned that I could better this time. a A nice little method was the one that Jon Harper used on his Hurricane during our club's Winter build last year, he made the fairing from foam and skinned it with a couple of layers glass cloth and it out exceptionally well resulting in a sweet profile that was simple to make, light and strong- no reason it couldn't be used on this model.

I wanted to plank the fairing roughly to shape and finish it with a skim of filler (as opposed to the dollops that I used on the 2015 model). It started so well with the first couple of planks but the 3rd didn't sit quite right. In need of inspiration I traced off the point at which the fairing blends into the fuselage skin, made a template and marked it onto the fuselage. Along the marked line I glued a 1/16" square strip cut from the off-cuts of soft balsa wing skin. After a while of contemplating what to do next, the penny dropped and I made a series of small formers with the radius of the fairing curve and glued them to the wing seat and the planking.

Whilst sanding the fairing formers, it came to light that the trailing edge of the fairing didn't extend all the way to the where the fairing would naturally run out. To extend the fairing trailing edge, an oversize triangle was cut from from soft balsa off-cuts and glued to the top of the laser cut trailing edge. To be fair, the angle and orientation of the laser cut fairing trailing edge was spot on, it was just the shape that wasn't quite right.

A set of 4mm wide strips were cut from the 1/16" balsa off-cuts to plank the fairing. These planks were plain rectangle in cross-section rather than the trapezoidal like the fuselage planks. The curve on the fairing is pretty severe in places so the planks were wetted before applying. I got into a nice little rhythm with the these planks: brush water onto the planks, blob a spot of CA on the formers and then apply the plank. The planks were fitted: one from the fuselage edge and then one from the wing edge until they converged at which point the planks needed cutting into fit into the varying width gap. It was all planked in a few minutes - considerably less time than I spent fussing and over-thinking it all.

Once the planks have completely dried out I'll give then a once over with abrasive and then deploy the filler.

 

Whilst the fairing planks were drying I got a few of the apertures cut in the skins for:

The gun slots

And the exhaust stacks

And I couldn't resist popping the canopy and cockpit fairing on just to see how she'll look:

 

Edited By Brian Seymour on 15/04/2017 09:31:08

[Dwain Dibley.]

Loving it Brian......

Nice work..

D.D.

[Brian Seymour]

Cheers Dwain, she's a cracking model to build.

This is the reason to strip plank, she has gone from an ugly duckling with planks all uneven and gappy to a slick, buffed and silky smooth fuselage:

That said, credit to Mario Castoldi for creating such a work of art - I'm just gutted that he designed it to shoot Spitfires down.

Of course it couldn't be that nice a fairy tail could it? I accidentally launched the fuselage across the room whilst picking out a set of wings for a model that I was taking out to fly - amazingly just a dent or two which filled easily, better to be born lucky than clever!

The fairings only needed two skims of filler and sanding so it really was more time pontificating than building.

The gun channels on the cowl have had a run of filler applying to make a radius in the bottom of the channels. The radius was formed by running the handle of my modelling knife along the bottom of it whilst the filler was still wet - you can see a black mark where some of the aluminium has reacted.

Whilst the filler was going off I got to work on the retract bays in the wings, no photos unfortunately but then again it isn't all that exciting yet.

Next job is the underside fairing which will be best done with the wing in place as the wing needs a little filler to blend it in.

[Nigel R]

that looks brilliant

[Dwain Dibley.]

A tip for channels in wood etc..

I use card, pushed in to the slot or whatever you have gouged out, and glued with CA or PVA, once dry cut it back flush and Hey Presto, a nice smooth, channel that can be sanded and painted just like wood.

That fuselage is looking mighty smooooooth....

D.D.

Edited By Dwain Dibley. on 18/04/2017 16:26:11

[Colin Leighfield]

Great job, well done. Absolutely no doubting what plane that is! When Castoldi designed the Mc200, bearing mind that the Folgore and Veltro are really re-engined versions of that plane, he wasn't thinking of shooting down Spitfire's. As late as 1940 we were negotiating with Italy to buy planes from them, one of them was the Caproni Reggiane Re2000. I don't think that many people are aware of that. Obviously it all changed when Mussolini was so convinced that we were going to lose that he declared war opportunistically and tried to join into the Battle of Britain. If he had thought we were going to win he would probably have declared war on Germany!

[RICHARD WILLS]

What a shape Brian ! All that work is paying off . She's the Sophia Loren of the aircraft world.

[Paul Johnson 4]

OMG..... told ya he was the messiah no wait over 25 definitley a naughty naughty boy....

Cause he is soooo much better than me...

[RICHARD WILLS]

I thought you meant Messiah as in Life of Brian .

Look what happened to him....

Still , at least he was singing to the end .

I got chucked out of Sunday School.

They didnt recognise talent in those days.

[Paul Johnson 4]

I heard about kids like you getting chuck out of Sunday school..... you were lucky mate they wouldn't let me in!

Still.....Always look on the bright side of life!

[Brian Seymour]

Cheers men.

Great tip on the card Dwain, I'm in half a mind to use that method on the 2015 model as I didn't put the gun channels in on that one and it seems like a cracking method for a retro-fit.

Excellent background thanks Colin, I didn't have the faintest that we had negotiated to buy Italian planes, the mind boggles thinking about how planes would look and perform if Mussolini sided with the allies.

That's a comparison and a half Richard - I can't remember now if there was any effort involved!

Paul, I've seen how you finished your Spitfire and how you're progressing the Bf110 - I can't help thinking the reverse!

[Colin Leighfield]

There are loads of interesting Italian WW2 planes that would make great models. One that I believe that we thought of buying was the Caproni Libeccio twin. I've always fancied the Breda Ba65 as a model as well. Not hugely successful, a bit like the Fairey Battle in some respects, but full of character. Like some of the Japanese types, we don't see enough of them. The Folgore and Veltro are outstanding examples of Italian design capability. I think you are going to be chuffed with the results of your efforts.

[Chris Walby]

Hi Brian,

Firstly great looking build you are doing there.

Secondly you initially mentioned:

Model Specs.

• Scale – 1:7
• Wingspan – 158cm
• Power – from 700w to 1000w 50mm dia. Outrunner *
• Weight – 3.1 to 3.4kg.

* Prototype had a peak power of 800w using: SK3 5045 450kv motor, 80A ESC, 5s4000 flight pack and 16x12 APC-E prop.

Could you let me know what you decided on in the end regarding motor, ESC & prop as I have a WR Hurricane, but it will be in the 4 to 4.5Kg area.

[Brian Seymour]

Cheers Chris, the WR Hurricane is a cracking model, I have got the similar size and weight VQ Models Hurricane 60. The power setup on my VQ Hurricane was cobbled together from various parts that I had kicking around and come out at 1300w: Turnigy SK3 5055 430kv motor, Hobbywing HV70A ESC, 8s3300mAh flight pack spinning up a 13x8 APC-E prop.

On this Macchi I'll be using an AXI 515kv motor, Hobbywing 60A ESC, 5s4000mAh flight pack and I'll prop it to give as close to 50A as I can.

[Brian Seymour]

I have, at last, been able to get back to the Macchi, she shouldn't take much effort now.

The gear wells, doors and underside fairing are the current work in progress.

The doors which stick to the oleos (for want of a better description) were quite flexible so I glued a strip cut from the scrap ladder left over from the hard 1/16" balsa to stiffen them up a bit. I used them as a template for cutting the wing skin for the wheel wells.

In hindsight, it may have been best to complete the underside fairing and get it smoothed out nicely before cutting the wheel wells but this way is working out.

With the sin cut, the oleos were fitted to the retracts and the innards of the wing and fuselage were Dremmel'd away to accommodate the oleo and wheel.

With the well made deep enough to accommodate the oleo and wheel the fairing was built up with a couple of laser cut parts and some chunks of off-cuts. On the original one most of the underside fairing was filer which was OK but I'm guessing that it came out heavier than balsa and considerably weaker.

The chunks of balsa were trimmed to accommodate the gear door and sanded to blend in with the surface profile of the gear door.

 

The inner gear doors have been made from medium 1/16" sheet laminated with the top sheet grain inline with the length of the fuselage and the grain on the underside sheet going inline with the span of the wing.

 

The fuselage skin was trimmed to the profile of the inner gear door and the gear door sanded to match the profile of fuselage skin.

 

Next job is to get the left hand side done the same and then get some filler into the gaps and final sanding.

 

 

[Paul Johnson 4]

Looking good Brian, I like the doors. How do you intend to operate the inners?

[Brian Seymour]

Cheers Paul, on the original model I used 5g servos to operate the inner gear doors but on this one I'll try a little trick that my flying buddy Graham Stone uses. His trick uses a spring to hold the door open, the door is connected to a lever via a push rod and the retracting wheel hub to presses onto the lever which closes the door. With a bit of adjustment Graham gets the timing of the door closing really nice.

[Ron Gray]

Take a tip out of the FMS book, the inner doors are held open by a piece of thin spring wire which the UC closes against and thereby pulls the doors closed. I'll the some shots of my T28 later to show you how it's done, but it works really well.

[Chris Walby]

Brian and Ron, please share your tips as I have a model that no matter how I adjust the doors I can't get the things to shut!

Thanks in advance

[Ron Gray]

I took some photos plus a short vid of the retract gear on my FMS T28 this evening

Youtube

Edited By Ron Gray on 04/01/2018 22:28:59

[Brian Seymour]

Cheers Ron, that's similar to what I'm going to do, it's brilliant in it's simplicity. The real Macchi C.202 also appears to use the retracting wheel to pull the door closed, Ill see if I can scan in a picture.

I'll document what I use as I make it, it will be nice to copy the mechanism from the real one but I may simply go for simplicity.

[Brian Seymour]

This is a diagram of the inner gear doors on the real plane from a truly excellent book "The Macchi MC.202 Folgore, a Technical Guide" by Maurizio Di Terlizzi.

In the meantime a few bits and pieces on the fuselage have bee done.

The front underside of the fairing has been filled and sanded. I used Bucks Composites fairing compound with 30min epoxy, this is first time that I have used and it exceptionally good. It really can be sanded to a feathered edge without crumbling and it sands easily.

The oil cooler and radiator have also been started, both are used to help move air around to aid motor cooling. The oil cooler has an air dam half way along to channel air from the front into a duct which leads to the front of the motor and the rear draws air out the fuselage from behind the motor. The radiator has an air dam at the front and is used to draw air out of the fuselage.

The oil cooler is a supplied vac formed component but to make it aid cooling a little prep has to be done. First off the fuselage skin was cut to allow air to flow in and out. The air dam is made from off-cut balsa, a basic rectangle was cut and then trimmed to fit inside the oil cooler and then a slot was cut in it to fit over the fuselage keel. After a bit of trial fitting and fettling it was glued to the fuselage formers exposed through the duct holes.

The radiator is built up from balsa, the assembly starts with laminating the sides and sanding the external profile. The sides are then glued to the box section inside the fuselage. Once the radiator sides are glued in place an air dam is cut from scrap and glued into position and then scrap balsa can be cut to shape and fitted around them.

Next job is to sheet the radiator and glue the oil cooler on and then blend them into the fuselage with sweet fairings.

[Brian Seymour]

The sheeting on the radiator was up next, cross grain sheet was chopped from hard 1/8" balsa, butt joined, and sanded. The curve is quite drastic for hard balsa so water was liberally brushed onto the external surface and left for a few mins to allow the balsa to absorb it. The wet balsa was most compliant and the skin was stuck on using CA. Once set the wood was dried out using my filming iron.

Wit the air dam fitted and the duct slots cut in the fuselage, the oil cooler needed little more than gluing in position. I used a combination of gorilla glue and CA to stick it on. I used the Gorilla glue on the gappy edges (where I had cut the a bit too much off when I liberated it from the scrap) as well as on the air dam to ensure that it was sealed. For those who have not used Gorilla glue, it expands as it sets.

A reasonable batch of epoxy and fairing compound was mixed up for the radiator, oil cooler, and wing trailing edge fairings. Before applying the filler mix the wing was fitted to the fuselage with cling film around the trailing to isolate it and prevent the filler mix from gluing the wing in place.

Once the filler had set, the wing was removed, the cling film discarded, and fairings sanded.

As I was in the mood for fitting fairings I stuck the cockpit fairing on. With the cockpit fairing on it seemed rude not to apply a bit of effort to the cockpit itself: the cockpit aperture was cut from the skin, the floor glued in, and the cockpit prepped for fitting.

The masking tape and paint were used visualise where the vac formed canopy should be cut - possibly not the best the method but its looking OK. The razor plane inside the cockpit is holding the cockpit floor in place as the glue goes off.

During the summer I had a go at making a 3d printed tail wheel and leg:

The tire is 3d printed rubber which took a bit of effort to get the right settings, the pivots and axle are Ø2mm steel pins running inside PTFE tubes. There is a bit of spring in it but I haven't finalised making it castering or steerable yet.

Next up will be a run of fairing compound around the cockpit fairing and balsa lining on the back of the cockpit and then covering.