The Warbirds Replicas Macchi C.202 is Landing!

[Brian Seymour]

The aileron was a pretty reasonable fit in the wing, a little was sanded off the aileron root rib, annoyingly I didn't have the sanding block square and sanded more off at the trailing edge - had to confess as it's plain as day in the picture. A little was sanded off the ribs either side of the balance tab. The aileron hinge rail facing needed a bit more sanding but by dry fitting at this stage the high spot are easy to see.

The pre-cut hinge holes lined up perfectly along the length of the wing. The hinge hole next to the root rib needed raising slightly to get the aileron aligned vertically. A small section that included the hinge hole was cut out and glued back in raised slightly and that perfected the alignment.

I'll get the other wing built up to this stage so that I can make sure the tips are sanded to match each other before sheeting.

[Ady Hayward]

Hi Brian, A very nice build of a fighter that is not seen very often. It is great to see that there are nice tweaks like the hinge holes being pre cut as these are a constant source of issues for those with few builds under their belts. The Spitfire kit was very nice, but now that the 3D printed parts are available it really opens the scope for more adventurous scale detailing for minimal weight penalty.

Adrian

[Brian Seymour]

Cheers Ady, having got the hang of the shrouded hinges on the Yak 9 I couldn't resist designing them in on this one, I saw the ones you did on the Ju88, very nice.

On the subject of hinges I got the elevator hinged. The tailplane skins have been cut to over-hang the hinge line and act as the shrouding. To prepare rear of the tailplane a drill wrapped with a piece of coarse sand paper was used to shape the hinge recess. There are slots in the tailplane core which line up with the hinge slots in the elevator, the slots in the core need to be opened to 3mm to accept the hinges. These were opened up using progressively larger drills, 2mm, 2.5mm and 3mm, this allowed the centres to be reset on occasions when the drill wandered.

On the elevator, the hinges were trimmed to the depth of the pre-cut slots so that once the hinge is pushed in as far as it can go the pivot point is the correct place. The hinge holes in the front face of the hinge post were elongated to allow for hinge to deflect.

The shrouding was tickled out just right using a sheet of sand paper wedged in the hinge line, this takes the high spots down whilst leaving the low spots.

 

With the hinges just nice, the elevator was pinned to the tailplane to keep it straight and the tips were sanded to match.

The elevator and tailplane are now ready for covering and fitting so I'll save that little job for when I'm waiting for adhesive to cure on other parts.

The right-hand wing is coming on at a pace, I haven't posted any pictures of it as it isn't too far different to left wing.

Edited By Brian Seymour on 28/02/2017 23:44:31

[Ady Hayward]

Hi Brian. I like your hinge work, very neat and I must try it on one of my next builds as it looks a good bit simpler than those on my Ju88.

Adrian

[Brian Seymour]

Cheers Ady, getting the design prepared for hinges is a great assistant. The balsa shrouding is pretty easy to sand to shape and is well protected by the control surface itself.

The other wing is up to the pre-sheeting stage, only one more little job not previously mentioned and it involves a nice little bit of carpentry. The front retract bearer takes a lot of abuse on landing so has been made from 1/2" square beech, these need a slot and notch cutting in to locate in the ribs and a chamfer cutting on to clear the undercarriage leg. The cutting lines were copied onto the wood and a junior hacksaw soon took care of the cutting.

I want to get a few pictures of the plane assembled without the sheeting and planking so I have moved onto the fuselage. With its interlocking components the assembly procedure needs a bit of thinking about.

First thing to do was laminate the wing-bolt-nut-plates and fit the captive nuts into them, a bit of care is needed to make opposite hand sets so I made the left and right hands at the same time.

With that little bit of prep taken care of the fuselage proper can commence. The vertical heel components were laid out on the building board and the formers and horizontal keel dry fitted. The vertical keel was pinned securely in place and formers were glued in place and the horizontal keel dry fitted to ensure the alignment. The two formers at the tail have got the tailplane mounting slotted between them and the formers either side of the wing have got a support for the wing-bolt-nut-plates slotted between them, so these assembled and fitted first.

The wing bolt plates were glued to the fuselage inner side before assembling to the formers. Once the glue on the formers had grabbed, the inner sides of the fuselage and the horizontal keel were glued and clamped in place.

Once the glue on that lot had grabbed the ply motor mount plates glued and clamped on along with the front former.

That was a nice little set of jobs, it didn't take all that long and suddenly half a fuselage appeared!

[Brian Seymour]

With the fuselage pined down dead flap the stringers were chopped to length, joined where necessary and glued on. The keels give the fuselage plenty of rigidity for bending up/down and left/right but even with the stringers on there isn't a great deal of torsional rigidity. The strip planking will give the fuselage a great deal of torsional rigidity but the application of the strip planking could cause it to twist so a set of trusses were cut and glued in-between the formers from the cockpit area to the tail. The trusses are cut from the 1/8"sq. balsa strip and they stiffen the structure right up.

 

That was just about as much as can be done with the fuselage pinned down so it was released from the board and left-hand-side components assembled. The inner-sides of the fuselage clamp several components, such as the servo trays, between them but these components are not rigid enough to hold the fuselage inner-sides in place so the left-hand inner-side was propped up and the formers glued to it.

Once the glue had dried the motor mount doubler was laminated to the front end, the components that sit between the inner-sides were glued into main assembly and the sub assembly glued on and clamped.

 

After that, the rest of the formers were glued on along with the horizontal keel.

Whilst the glue was going off the nose ring was laminated and once set it was glued on.

 

Once the glue on that lot had cured the stringers and trusses glued on. It all seemed a bit too easy but I haven't got onto the strip planking and cladding the fairing yet!

Edited By Brian Seymour on 05/03/2017 22:15:04

[Brian Seymour]

For the folk looking to use IC to power the model, Jon and I had a look at adapting the kit for an engine, in particular the Laser 70 which will be pretty much ideal for powering this model. The photos show the engine in place and there is enough space for an engine and a tank. If there is enough demand then I'll look at adapting the model although most modelers will be able to make the necessary adaptations to suit their engines

We talk around fitting a bulkhead between the inner sides for the engine mount and sealing the front end at the former just behind the cowl.

[Denis Watkins]

This is looking a very attractive build Brian and I would be surprised that this reaches the all up weight specified, as it looks to be such a light build.

Am almost exclusively 4 stroke motors with my models now, and they use so little fuel, I think a small yellow 9 oz tank would drop into your space and give adequate air time IMHO

Edited By Denis Watkins on 07/03/2017 07:23:58

[Brian Seymour]

Thanks Denis, a 4-stroke setup will almost certainly save a few ozs over the electric setup that I use. I'm looking forward to seeing how folk get on with a 4-stroke setup, from the performance figures that Jon has told me, a 70 4-stroke will give a bit more power than my intended electric setup.

[Jon H]

If we fit an ic version of the apc 13x6 to your MkI model we can get an apples to apples comparison of rpm etc

[RICHARD WILLS]

I dont mind an apple,

[Brian Seymour]

Sounds like a plan, I'll have to pop a rev'ier motor in, she only spins up at 6k with the low kv motor that I have been using, otherwise it'll be a case of chalk and cheese - the cheese will probably go reasonably well with the apples but I'll skip the chalk.

There hasn't been a vast amount done in recent days, the cowl was a nice little job. I built it in the fuselage using a sheet of polythene t ensure that it didn't stick to the fuselage. The base plates where clamped to the horizontal keels, the front and rear formers were glued to the base plates and clamped to their adjacent formers and then the other formers were glued in place topped of with the keel.

Once that lot set the gun channels were glued in .

 

With the gun channels glued and sanded the stringers were glued on.

 

 

Edited By Brian Seymour on 09/03/2017 22:06:43

[Victor Arcudi]

Wow Brian, That really leaves me for dead! Since mine will be a C.205, I'm still modding the tail section to accept a Robart mini tailwheel retract.

I'm using a Dynam Bf-109G type spinner, which has the ideal shape, all I needed to do was modify the prop nut which was shortened by 3mm, bored out & threaded to 10x1.5mm to accomodate the prop driver. The motor is a 400kv Turnigy G60 which I'll run on a 6s 4000 or 5000mah pack, depending on which one gets the CG right. As for the prop, it'll be a MAS 16x8 3 blader.

The only mod after all that will be the beer barrel shaped radiators under the cowl and the addition of the wing cannon.

[Brian Seymour]

The retracting tail wheel is going to be ace, I reckon, on the basis that the 2015 model balanced with a 5s4000 pack, the 6s4000 should be enough to offset any additional tail weight.

My one has progressed well so I'm likely to get her finished before you but I expect that your finished model will leave my one for dead in terms of finish.

[Brian Seymour]

With the flying weather at the weekend I got significantly less done on the build than I had hoped!

The fuselage is up to a nice stage with all of the stringers and trusses glued in, the cowl has had a few components added to duct the air from the air filter to the motor as well as the plastic braces for bolting the air filter on. The next stage is to fit the radio and control gubbins as it is much easier to see what is going on without the strip planking in place.

Before fitting the control linkages etc. I built the fin and rudder and got them hinged. The rudder is pretty much the same as the elevator: a core plate with root and tip cross grain doublers, ribs slotted in from the front and a hinge post glued on to the front.

The fin is moderately tricky but doable with one set of hands and a set of clamps. The ribs are slotted into core plates, a leading edge core plate locates the ribs, a hinge post is added either side and then spar plates (for want of a better description) locate on the ribs bringing all of the components into perfect alignment!

Fin components laid out:

 

Ribs glued into the core plates:

 

Leading edge core glued on:

 

The hinge posts glued on front and back:

 

The spar plates glued on either side:

 

With that little lot setting the skins were joined:

 

Once the glue set on the core, it was given a once over with the Permagrit:

By that time, the skins were ready to be glued on, they were glued on both a the same time which was pretty simple if a little messy where I picked a glued zone to hold the core:

The skins were lined up and clamped to the leading edge at the root and then shuffled and clamped to align the trailing edge at the tip. Clamps were then added working along the leading edge from root to tip, then along the spar and finally along the trailing edge. The trailing edge skins overlap so that they can be used as the shrouding for the hinge.

The hinging was piece of cake having got to grips with the technique learnt from hinging the elevators. The shrouding has ended up being little over 2mm to accommodate the bigger swing required on the rudder but it still does its job of concealing the hinge line.

The fin and rudder still need final sanding but it's time to break out the radio and get it setup before strip planking.

Edited By Brian Seymour on 13/03/2017 14:14:00

[Brian Seymour]

With the main structure complete and the skins not on yet it is the ideal time to plan the radio install. The wings are pretty much a given with servo boxes build in but there is a bit of planning required for the receiver, receiver pack and ESC location.

The model has been designed to accept standard size servos but adaptor plates are supplied for using 9g size servos. I am using 9g size Savox servos (actually weigh 15g) so the servo bolt holes were drilled into the adaptor plates, the screws fitted and then removed and thin CA run into the holes to toughen them up a bit before gluing in place.

I used the same location for the receiver pack as on the first model which is pretty much directly over the CG, the flight pack has plenty enough leeway for adjusting the CG. To keep the receiver pack located, a retaining crate (for want of a better description) was built up, the pack is held in place with Velcro but the crate stops it coming loose. There is a nice little gap on the opposite side of the fuselage to the elevator servo which is ideal for the receiver but to keep it out of the way an extension to the fuselage inner-side was glued on.

The model was assembled without the sheeting/planking to show its construction.

On with the sheeting and planking!

Edited By Brian Seymour on 19/03/2017 11:13:19

[Bucksboy]

Marvellous! Looks very good and I'm sure this thread will act as a good advert for the plane when it's offered for sale. Keep on posting!

[RICHARD WILLS]

Blimey !! I really like that Brian . I hope that little bloke's got his thermals on though .

Bit breezy .

If you really like building this has to be a very satisfying journey .

Great job Brian ,

[Dwain Dibley.]

Lookin' Good Nakeeeeeeeeeeeeeeeed !!

D.D.

[DavidKP]

That looks amazing, might just be tempted to buy one of those and put it away for a few years until I feel confident enough to attempt it

[onetenor]

What has turned the balsa so white ?

[Paul Johnson 4]

Truly impressive Brian

[Colin Leighfield]

It looks as if you will have reason to be very pleased with that Brian!

[Brian Seymour]

Thank you all for your kind words and support.

I'm also following the Bf110 thread as I want to join the party and build one once the Macchi is finished, it's a cracking thread (and kit and subject) and gives a great sense of camaraderie.

With the fine building weather, I managed to get a fair bit more done yesterday afternoon/evening but I'll do a detailed update once I have uploaded photos.

[Brian Seymour]

Both wings have got their top skins glued on, the following procedure looks like effort but is a sequence of several pretty simple stages.

First job was to make a jigging tab for the 2nd rib from the tip, in (mis?) handling the wings I had managed to accidentally break off pretty much all of the jigging tabs on the ribs from the root of the aileron to the tip. The ribs either side of the flap pocket still had the jigging tabs intact so it only needed one more jigging tab near the tip to stabilise the whole of the wing.

A template was made to get an idea of the overall size of the top skin, the wing was laid down on the board:

The wing plan was traced to make a template, the trailing edge of the template was cut to size and laid over the wing locating it against the guide faces on the jigging tabs on the ribs either side of the flap pocket. The template was held in place with weights so that it could be trimmed to the profile of the top surface, I left ~3mm extra on the leading edge and tip so that there was a little leeway for misalignment.

The wing was put to one side and the template laid flat on the board. The top skin starts from rib R4 so the leading edge sheet was pinned down with the root side just inside the position of rib R4 and the joining edge over the main spar. The trailing edge sheet was pinned down aligning the trailing edge and then the root edge was trimmed to be just inside rib R4.

The centre sheet was butted up to the leading edge sheet and slid under the trailing edge sheet.

Using a steel rule as a guide, a cut was made through the trailing edge sheet and the centre sheet, taking little more than a sliver off of the trailing edge sheet. This created a perfectly mating join.

The off-cuts were removed and the joins taped over with masking tape.

 

The taped skin was flipped over, at this stage the join lines should have been sanded so that the thickness matched, foolishly, I did it the hard way and sanded the join lines after gluing - it has worked out OK but was harder work than it needed to be.

The joins were folded back, glue run along the mating faces and then weighed down flat and left to set.

 

Once set, the skins were glued to wing by: laying the wing on the board, applying glue to the contact surfaces on the tops of the ribs and spars etc., locating the top skin on the guide faces on the jigging tabs on the ribs either side of the flap pocket and then weighing and pinning the skin down. The tips have been left unglued, they will be glued after the lower skins have been glued on so that both top and bottom tip skins can be clamped together.

Edited By Brian Seymour on 21/03/2017 23:20:22