Here is a list of all the postings Brian Seymour has made in our forums. Click on a thread name to jump to the thread.
|Thread: The Warbirds Replicas Macchi C.202 is Landing!|
For not a lot of effort the wing has come on just nicely over the past couple of evenings.
A few components were added to the underside: lining for the servo boxes and ply wing bolt plates. The wing bolt plates being as easy as falling off a log and the servo box liners almost as easy, the tricky one being the lining for the tip-side of the aileron box for which there isn't a lot of space but it does go on without bending or breaking.
The wing bolt plates:
The servo box liners:
With that gluing the top surface sheeting at the root was fitted. The top sheeting has been stepped to give the fairing a bit of strength rather than feathering out to delicate edge. The sheeting fits either side of the spars which are proud of the top surface of the ribs.
Before fitting the main wing sheeting I want to make sure that the aileron hinging lines up and has enough travel as it is a lot easier to make adjustments without the sheeting - that meant taking a break from the wing to build the ailerons. The ribs on the ailerons are profiled to continue the washout from the wing so the ailerons need to be made as a left and right hand - the only way that I was going to do that successfully (without the help of a team of puppets) was to build both at the same time.
The ailerons are built from a 1/16" thick trailing edge core and 1/8" thick core, both slotted to locate the ribs and, to make left and right sides easily identifiable, the upper surfaces of the core plates are flush. Once the ribs have been glued in between the core plates, the front edges of the ribs need to be sanded flush as they do not run perpendicular to the hinge line. The hinge rail can then be glued on and then the components that build up the balance tab are glued on. The hinges have been designed to be shrouded which requires a facing with a full radius sanded on it, the sanding was done before fitting to save smashing the ribs at either end of the balance tab.
Once the glue on that little lot dried the ailerons were given a going over with the sanding block, a nice radius sanded on the leading edge of the balance using the laser cutting discolouration as a guide. The hinges were dry fitted, the hinge rail has holes laser cut for the hinges, these holes were used as a guide for drilling the holes into the core plates. There is little more to do but both ailerons are ready for trial fitting and fettling.
Edited By Brian Seymour on 23/02/2017 22:07:22
Cheers, I don't know about not catching up... talking of jobs, my firm has just won a really nice project so progress on the model may sadly get subdued - time to find an agency that doesn't discriminate against puppets!
To be fair, the quality of the laser cutting is first class - cheers Phillip, so it assembles nicely and I have been able to simply glue stuff without needing to fettle anything. Also, apart from the rear spar webs just about anything that can be laser cut has been.
Cheers Colin, it's better than OK to follow along - I'm glad that folk are interested.
Cheers Richard, sadly this is high employment area and you can't get puppets to help for love nor money - although I haven't tried offering them money.
Glynn has done a sterling job on the 3D printed parts, they look ace and the air filter has come out little over half the weight of the one I used on the first model.
I also got another couple of bits done on the wing despite not having any help from the local puppets. The rear spar webs have been chopped into shape and glued on. Three of the web sections that house the aileron hinges have been laser cut with the holes for the hinge also laser cut, the intention is that the hinge holes line up with hinge holes in the aileron - I'll find out in the next day or so whether it has worked out.
With the servo bay ribs glued in place and the adhesive thoroughly cured, yesterday saw a sterling rate of progress.
The next stage is to fit the ribs that locate in the false leading edge and glue the flap rail. I was still careful to go with the basics of making sure that the ribs were perpendicular to both the board and the main lower spars. The top jigging spar was dry fitted to ensure alignment and it was left for the glue to cure.
The flap hinge rail was fitted which tied the trailing edges of the ribs up to the aileron into line - not that any were out of line.
Once that was dry the rest of the ribs were fitted along with the bracing for the wing bolts. As there was no reason not to glue the top spar jig, that was also glued on and then the laser cut inter-spar webs were also fitted.
Whilst that little lot was curing the tip end of the top spar was shaped to feather out. The rear spars were fettled to some extent to ensure that they didn't protrude beyond the upper and lower surfaces of the ribs. There are also link spars which go from the root and join the main rear spars with a scarf join which was planed and sanded to make a nice fit.
By the time the spars were prepared the glue for the webs was dry enough to glue the spars in place and glue on the wing tips on.
It was a nice little day's progress, I even got out flying in between stages.
Edited By Brian Seymour on 20/02/2017 19:31:50
I have got going on the wings, there a bit of prep to do with laminating and sizing spars, laminating the rear retract plate and building up the laminated wing tips.
The main spars are a lamination of spruce and balsa, the spruce for the strength and the balsa to make sanding easier and were laminated using epoxy and clamped flat and straight to set.
The wing is built up on the lower spar arrangement so the spars have to be sanded to thickness to enabled the jigging tabs to work as intended. Both the spruce and balsa strip were marginally thicker than the nominal thickness so when assembled before sanding the jigging tabs did not sit flush on the building board (and my board is dead flat). I made up a bridge to assist sanding the spars to thickness, the bridge is held over sand paper and the spar pushed too and fro under the bridge until there is little resistance. Using 80 grit aluminium oxide paper the spars were quickly sized and then buffed up with wet and dry.
The lower spar arrangement is complicated by the need for a recess for the retract so the retract mounting plate forms a structural link between two spars. To aid assembly and lining up the spars there are upper and lower laser cut rib jigs, the lower one sits upright on top of the lower spars and the ribs are located in notches.
The first proper assembly stage is to glue the ribs either side of the servo bays and fit the servo mounting rails. The the flap servo is mounted between the same ribs that go either side of the retract. This little assembly is a bit of a Chinese puzzle requiring:
It's a bit tricky but humanly possible and forms an inter locked "strong box" which transfers the load. The aileron servo bay is breeze in comparison requiring the ribs to be located the jigging spar, the aileron servo rails located into slots in the ribs and then the ribs set perpendicular to the spars and board.
To assist the line up the front false leading edge assembly has locating slots so was dry fitted along with the top jigging spar.
That little lot was left pinned and clamped over night to set.
The lower spars, jigging spar and retract plate ready for the ribs to be slid on from either side.
The assembled flap/retract bay.
The assembled aileron servo bay.
Edited By Brian Seymour on 19/02/2017 09:00:32
Next on the easy jobs list is the tailplane. The tailplane is build up one side at a time on a core plate which also acts to jig the ribs.
The laser cutting capabilities are put to the test with the core plate as it is 4 butt joined pieces to give a cross grain base made from soft balsa with a hard balsa leading edge which is made from two parts the keep the grain as long as possible. First job is to pin down the 4 parts of the core plate butting up to each other and glue the ribs and hinge post onto it: and then run a bead of adhesive down the join lines of the core plate.
Whilst that was drying I repeated the above process for the other tailplane half and butt joined the balsa sheeting.
By the time I had got that little lot done the adhesive on the first tailplane half had cured, so it was released from the board and the ribs etc. were added to the opposite side. The tailplane uses a symetrical section so it's the same view as the above picture except that it isnt' pinned to a building board.
This was a nice little building sequence as the glue dried quickly enough that one tailplane half had dried by the time I had finished assembling the other. Next task involved sanding so I decided it was best to leave the assemblies over night to fully cure.
The hinge post needs a little work with the sanding block to blend it to the shape of ribs. The ribs also benefit from a once over with an abrasive to get tops in-line with each other. The discolouration from the laser cutting provides an excellent guide as to how much has been sanded:
The sheeting isn't too much like hard work to fit and doing both side of the tailplane half at the same time makes sense, it just gets a bit tricky avoiding touching the glue. The sheeting was clamped in place starting from the leading edge at the root, working to the tip clamping every inch and then along the trailing edge back to the root pulling the sheeting tight to the ribs as I progressed. The sheeting over-laps the trailing so that the hinge can be shrouded.
After leaving the halves over night and sanding the leading edges to a nice shape it's all over bar the hinging and finish sanding with the elevator in situ:
It's time to stop procrastinating - next job is the wings, the plan is on the board ready to go.
Edited By Brian Seymour on 16/02/2017 22:04:36
|Thread: Kit builders, what would you like???|
I'll go for an early variant electric please.
On the electric vs IC front, I'm going electric because I have a couple of paired sets of flight packs that will be ideal. I can't help thinking that the grass is greener when I see my fellow club flyers blatting twin 2 and 4-strokes (not on the same plane) across the sky with the poetic tune of synchronised engines.
|Thread: Who wants a Warbird Replics Hurricane?|
As a friend of Jon's who has got a VQ Hurricane:-
Best use this for reference only as the wing section on the VQ isn't as good as that on the Warbirds Hurricane and the stubby undercarriage legs restrict the prop diameter.
Apart from half an inch here and there the VQ Hurricane 60 is the same size albeit a little heavier. The power setup I use (see below) is more than adequate and, as suggested by Chris, the flight pack is a little oversize to get the benefit from a little more power and duration for the required nose weight.
Flight Pack: 8s3300mAh
I know it's a bit OTT, she still flies fine on a 13x6.5 APC-E at 1020w but I enjoy the extra power from time to time. The pack choice came about from using two 4s3300mAh packs that I use in other planes.
|Thread: The Warbirds Replicas Macchi C.202 is Landing!|
Indeed, it's like an ideal post pub lunch afternoon skive job, nice and easy and there is scope for a little artistic licence with the sanding which is just enough to make it interesting without being a ball-ache.
Apologies for naff picture, here's a better one:
The 3D printed stack is one that I printed so it's very rough compared to the ones that Richard & Glynn print. I won't be fitting the stacks until the painting has been done to save having to keep it masked.
It looks like it won't take a great deal of effort to build the kit as a 205, the RAAF scheme is cracking with the toned down hoops.
Having laid the Laser 70 drawing over the plan there was a reasonable amount of space for it so shouldn't be too much like hard work to fit.
Having not done any serious building since April last year I decided to ease myself into the build with the simple exhaust fairings.
The exhausts double up as an aid to cooling by channeling fresh air into the front of the motor via the aperture in the front of the fairing and drawing air out from behind the motor through the exhaust stacks. On the already built Macchi the stacks were made from folded litho plate which was quite a nice job but it's fiddly and easy to crack rather than bend so not really practical to kit, on this one they have been drawn up to be 3D printed. 3D printing the exhaust stacks and fairing as one component seemed like a good idea but it involved a lot filament, time and added weight so the fairing was redesigned as a laser cut balsa assembly.
The fairing is little more than a balsa box made from light 1/16" balsa with a 1/4" thick slab at the front which is sanded to shape. I found it best to build them in 3 stages, glue the components shown in the 2nd picture and let the glue grab before adding the other fairing side and leave that little lot to set. The next stage requires a bit of clamping so I left the assembly overnight before adding: the air dam, which ducts air into the front of the motor, and the 1/4" thick top slab, it was clamped up and left overnight before sanding the front to shape.
It all went together just nicely and has come out weighing just 3g so well worth suffering the pleasant building experience.
3D Printed exhaust stacks and fairing in one piece, they came out a bit heavy at 29g each side.
Internal ducting of the fairing, an air damn is fitted at the front of the two upright parts and channels the air to the front of the motor.
The completed and sanded exhaust fairing.
Edited By Brian Seymour on 13/02/2017 23:00:08
I'm pretty sure that sums up the differences between the 202 and 205. With a bit of luck Vic will chip in on this as I think that he will be making his kit into a 205.
The VQ models are pretty reasonable to fly, I got the Fiat G.59 as my test-bed for the anticipated power and radio setup on the Macchi. She is little over 1/2lb heavier than the Macchi despite having an identical power and radio setup, this drains the flight pack a little more quickly and makes her a bit fussier in loops and the like but is still fun to fly.
Macchi C.202 Folgore (Lightning)
The Macchi C202 was an Italian designed and built front-line fighter aircraft that predominantly served in the Italian Air Force (Regia Aeronautica) during WWII. Powered by a Daimler-Benz DB601 engine built under licence by Alfa Romeo and denoted RA1000, the C.202 outperformed almost all other fighters powered by the same series of engines including the deadly Bf109E. She was a formidable foe for allied fighters of the time scoring victories against such aircraft as the Spitfire, Hurricane, P40 and P39 and during the defence of Malta only the Spitfire Mk.V’s were encouraged to engage it in combat.
Origins – The Italian Spitfire?
The Macchi C.202 was designed by Schneider Trophy winning designer Mario Castoldi drawing a distinct parallel to the Spitfire which was design by R. J. Mitchell also a Schneider Trophy winning designer. Where Mitchell won three consecutive Schneider Trophies thus putting an end to the competition, Castoldi designed only one winner but to even things out he also designed the Macchi M.C.72 which set the world record for the fastest piston engine seaplane, a record that stands to this day. The C.202 retains its racing heritage with the narrow chord wings, compound curved fuselage and a cockpit fairing that could easily have come straight off a racing plane. In combat the C.202 was a very good match to the Spitfire Mk.V , the C.202 the more capable flyer and Spitfire better armed.
With CAD design and the impressive abilities of modern laser cutting, recreating the sweet surface profiles and shapes of the Macchi has been considerably simplified. The model uses traditional balsa and ply construction with a handful of vac formed components and, just to stamp modernity on the design, several 3D printed scale details. Precision laser cutting has been taken to extreme lengths to create self-jigging assemblies that be slotted together, aligned and glued. The fuselage is strip-planked to give a rigid lightweight monocoque naturally reproducing the sweet compound curves of original aircraft. All control surfaces have been design to have shrouded hinges which result in a visually and aerodynamically clean airframe. As per the original, the control surfaces have faithfully spaced ribs which show through the covering film.
It is cracking subject to build and fly, the proportions lend themselves almost perfectly to produce a model which flies very nicely and the long snout makes balancing the model a breeze. There is wide a variety of colour schemes and squadron insignia to choose from which are predominantly free-hand painted. Check out these models to see what can be done:- **LINK** **LINK** **LINK**
* Prototype had a peak power of 800w using: SK3 5045 450kv motor, 80A ESC, 5s4000 flight pack and 16x12 APC-E prop.
The kit is being produced in collaboration with Warbirds Replicas and will soon be available as kit from Warbirds Replicas. It is an evolution of the Macchi C.202 model that I built a couple of years, the design has been updated with quite a few improvements and adaptations to better suit production, simplify construction and make it more robust to handle the stresses of everyday flying. This is a video of one of the early flights: **LINK**, this video shows her taxiing and taking off: **LINK**
These following pictures of the model were kindly taken by Jon Harper at one of the club’s Warbird Wednesday meetings:
This blog will feature the pre-production prototypes that Richard, Vic and myself will be putting together so expect to see Richard and Vic chipping in. You almost all know Richard so needs no introduction. Vic is an expert modeller and self-confessed rivet counter, having seen pictures of his other models, I am really looking forward to seeing his build. Vic is based in one of the most picturesque areas of North Eastern Italy.
|Thread: Balsa bashing|
I'll 2nd that, cracking colour scheme too.
I finally got round to measuring the controls throws:-
She is still great fun to fly and despite a few Rodney moments hasn't needed much hanger time. I have found that when landing with the flaps down it's best not to go for a three pointer as she balloons up and landing on the mains still looks sweet enough. She lands fine without flaps but as she is sleek and streamlined (and I built her a little on lardy side) she doesn't slow up much and I tend to over-shoot.
Taking off from the club's Chinnor strip.
Top notch, she looks sweet and a half!
Richard, what can I say.. you've come to the right blokes. I take it that the couple of dozen is the monthly requirement as we'll sweat to hit that volume weekly
Top job Guy, cracking colour scheme done sweetly.
Nice progress on both, Jon - the metal covering looks ace.
Andy, I guess that the recommended electric setup on the Yak is the same as the Spitfire but I used some kit kicking around from an airframe that I sold:-
In the meantime I had a couple of exhaust stacks 3d printed (thanks to Richard and Glynn), the finishing process applied has nicely smoothed out the contour lines that 3d printing usually leaves. The contour lines are very faintly visible but I reckoned that it gave them character so painted straight onto them and glued them in:-
She has racked up quite a few flights now and she is still my current favorite, get them flying fellow builders - you're in for a treat!
The Yak had a nice little outing at the club's Fun Fly-in on Sunday, I didn't use her to compete but a got a few flights with her after the competitions - the warbird fun started when the Fun Fly finished!
Jon took her up so, with a bit of luck, he'll divulge a technical and non-biased appraisal of the way she flies.
In the meantime, my biased appraisal is that she is superb! With 970W she has an abundance of power, easily takes off on 3/4 throttle, doesn't peter out on vertical climbs and W.O.T. fly pasts almost crick my neck. By the time I flew her the breeze had dropped just nicely and there wasn't much in the way turbulent air so she was responsive, stable and predictable. Big loops are a breeze, requiring a bit of right rudder to keep her honest on the way up and barrel rolls are easily executed. As it was pretty calm I didn't get round to landing without flaps but she lands easily with full flap in dead calm conditions, the half flap setting seems to make her balloon up when flaring. Flight time varies from 7mins for full on recreational flying to 10mins when pottering round between tricks.
The CG was set according to the plan and is just about right for me.
That's sweet how they operate one at a time and they move at nice rate.
The Yak is ready for action, the magnets hold the battery hatch tightly so with the elasticated chord I've got be in with a chance.
To fit the magnets I used a tapered reamer to make a couple of holes through the crutch plate and glued offcuts to the underside of the crutch plate to make the hole a recess. The magnets were glued into the pockets with CA which worked surprisingly well. To mark the position of the magnets in the hatch, the hatch magnets were placed on top of the crutch plate magnets and covered with paint and the hatch fitted, the paint transferred onto the hatch highlighting the exact position. Recesses were cut into the hatch with a scalpel, they came out slightly oversize so a strip of Solartex backing was used to isolate the crutch plate and crutch magnets, the hatch magnets were positioned on top of the Solartex backing, the recesses in the hatch filled with epoxy and then the hatch fitted. Once the epoxy cured the hatch was removed and Solartex backing removed - it came out just right.
Crutch plate with magnets:-
Magnets in the hatch:-
A couple of other pictures from the final stages:-
Air duct in the cowl for motor cooling, made from 1/16" balsa:-
Motor mount with ESC, also the hole through the firewall to draw the hot air our from the cowl:-
Edited By Brian Seymour on 05/05/2016 22:04:08
Thanks Nigel, I'm glad that this thread has been inspirational. The Lavochkin kit has got some sweet details and has the look of a menacing airborne brute, all the best with the build.
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