Phil Cooke Posted March 9, 2018 Share Posted March 9, 2018 Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 9, 2018 Author Share Posted March 9, 2018 With the Sarik woodpack here and awaiting attention and with all the introductory work to the MB Project now more or less complete, it's about time I got cracking with the build! I'm aiming to get a fair bit done this month before the flying season starts on April 7th! I've decided to go for something a little different - a predominantly white Sea Hurricane IIc. The full size I'm modelling is NF672 from FAA 835 Sqn, HMS Nairana - circa Summer 1944. The IIc has the 4 x 20mm cannons I'd like to replicate and with it being a Sea Hurricane it also has an arrestor hook - so a couple of nice scale features to tackle. Although 'white' on top, the Sea Hurricanes had a really tough life on deck, and the model will give me a good opportunity to practice some heavy weathering techniques with the air brush. The underside is a bit of a mystery - in many historical photos or 3-views it's white all over - in others it has some makeshift D-Day type stripes painted onto the wings, and even rarer still it was periodically seen with a duck-egg blue underside, again with stripes - and this is the scheme I'm going to go for. A couple of photos of some excellent plastic models found on the internet - not my builds I must add! So with that I'd better get going... I've tidied away some of the other modelling jobs and ongoing projects, dusted everything down and even bought myself a new building board. I've just made the minor adjustment found necessary last night to the 'as supplied' fuselage side panels, so lets get going! Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 13, 2018 Author Share Posted March 13, 2018 After a lull in progress whilst the PSSA enjoyed their Avro Heritage Museum visit, I've finally got some building underway! I decided to start with the basic fuselage assembly. Initial job was to layup a left and right handed pair of fuselage sides with former positions and doublers located using the Fuselage Layout on Sheet 2 of the plan as reference. The fuselage sides are just over 36" in length, as such they are formed from 3 pieces, these were glued flat on the board once the additional trimming ops were performed as described in the woodpack queries thread. I found that having trimmed the fuselage sides down to the required line, the front fuselage piece was still a bit 'sloppy' in its keyed housing - I elected to fix this by adding an additional 1/16" strip to the rear face of the component - effectively pushing it tighter into its location. Worked well - this piece overhangs F1 and will be sanded back flush to form the final spinner mount - so this has no effect on the finished model. Detail on front section 1/16" extension to locate it tighter into the keyway...maybe I left my fuselage sides 0.2mm oversize after the trimming op? At the tail seat - the rear section of the upper fuselage half is very thin and delicate until it's glued to its lower half, I elected to use a scrap block to pin this section into position without the risk of damage to the fuselage itself. Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 13, 2018 Author Share Posted March 13, 2018 Marked up with the position of all the fuselage formers and doublers... accurate assembly will later depend on these lines so it's worth taking your time and getting this done precisely. Left and Right handed pair required! Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 13, 2018 Author Share Posted March 13, 2018 The 1/2" x 1/8" balsa doublers were then added, from front to rear, as were the 1/32" ply wing saddle doublers. The 1/2" x 1/8" doubler will run short at the back end if it is flush mounted at the front - this is fine as you have to feather the doubler down to zero thickness at the back end to enable the tail to be pulled in later. Quote Link to comment Share on other sites More sharing options...
J D 8 - Moderator Posted March 13, 2018 Share Posted March 13, 2018 The January 2018 issue of Aeroplane has a very good feature about the Sea Hurricane with an illustration of an all white aircraft similar to the model pictured .[ different codes ] Edited By J D 8 on 13/03/2018 16:07:40 Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 16, 2018 Author Share Posted March 16, 2018 To complete the fuselage sides prior to any assembly you have to remove the area of 1/2" x 1/8" fuselage doubler (shown hatched) such that it sits flush with the 1/8" fuselage side tail seat profile. There are a couple of 'composite' formers which need to be assembled before the box fuselage can be joined too - F3 needs F3A gluing to its front face - for stiffness around the L/E wing dowel, the rear wing bolt plate needs to be glued together (the laser can't cut 1/4" ply so 2 sheets of 1/8" ply are supplied) and the 1/8" balsa battery box was assembled too. There was a very familiar feeling generated when assembling the battery box... It is of course a feature we have employed now on ALL 3 PSSA Mass Build designs - Jet Provost, Skyhawk - and now the Hurricane! Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 18, 2018 Author Share Posted March 18, 2018 Been scratching my head over the former positioning issue identified (and detailed in the woodpack queries thread) in particular those central 'box' formers which are constrained both top and bottom by doublers already glued in position. With the fuselage side pinned down accurately on sheet 1 over the wing seat, vertically aligning F3 and F7 at the base left me with a clash on the main 1/2" x 1/8" fuselage doubler. F3 shown below. F7 was the same... I've modified my formers simply by removing a little more material so they will slip over the doubler when seated and the fuselage sides pulled over... I needed to remove 2.5mm of material (hatched area) which then allowed the formers to seat correctly in the required position, as shown with F7 below. Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 18, 2018 Author Share Posted March 18, 2018 Before the fuselage can be joined around the central box section, I needed to assemble the battery tube and nose former F1 - F3 sub-assembly. An overlay of formers F1 and F2 onto the plan suggested that F2 would also require the same doubler modification, however F1 did not. The simple former mod on F2 is shown - again 2.5mm error correction on height. Accurate assembly is eased if you mark up the battery box with the required position of F2 - and don't forget to shorten your battery box by 3mm so it all remains flush at the front for when you fit F1. Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 19, 2018 Author Share Posted March 19, 2018 With the nose section sub-assembly complete, and with the corrective mods made to formers F2, F3 and F7, the fuselage box assembly can begin... Glue is only required on the lower portions of the attaching formers as the fuselage sides still have to 'pull around' onto the formers at a later stage. Below - F3 is glued square and vertical - you should find the composite F3/F3A former locates very well onto the 1/32" ply doubler - good to perform a vertical alignment check at F1 too by ensuring the slots in the former lie directly over the fuselage doubler. F7 and the captive nut plate fitted all square too... 5 minute epoxy used on all these joints. First half finished and curing... Before I remove the fuselage from the board I'm following Stephen Bowlder's lead and adding an additional strip of 2.5mm doubler on the top face of the existing doubler, fixing the vertical location issues on formers F4, F5 and F6 (all added later from the top) Edited By Phil Cooke on 19/03/2018 13:42:36 Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 19, 2018 Author Share Posted March 19, 2018 Before joining the fuselage sides around the wing box I modified the fuselage doubler locally where it will interface with F4, F5 and F6, simply by adding a 2.5mm strip of 1/8" balsa, as shown. This will correct the error in the formers as supplied and seat them at the required height when fitted. With that done, I reversed the fuselage and pinned the other side down to the board. A dry fit of the two halves proved an accurate assembly so a little epoxy was added in the required areas and with squares ensuring accurate alignment at the front and rear it was left overnight to cure. A square set at the rear tail seat and on the F1 fuselage doublers up front helps ensure everything is absolutely aligned. Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 20, 2018 Author Share Posted March 20, 2018 The plan shows some stiffening triangular stock supporting key joints around the wing mount plate - and its a good idea to fit these now before we start to load up the fuselage by pulling in the sides at the tail and nose... I used 3/8" triangular balsa - some above the plate at the rear up against F7... and some below the plate running forwards. Whilst the material was out I also elected to bolster the joint ahead of F3 (not shown on plan) Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 21, 2018 Author Share Posted March 21, 2018 The box fuselage was pinned and chocked down to the plan view drawing and with all the datums accurately aligned I pulled the tail in on the centreline. I used some hard balsa blocks to spread the load from the grips without damaging the model. I had to feather down the 1/2" x 1/8" fuselage doublers a little to get the fuselage sides to meet as required right at the back. Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 21, 2018 Author Share Posted March 21, 2018 Once the clamps were off the tail I beefed up the joint with a couple of small balsa wedges... Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 21, 2018 Author Share Posted March 21, 2018 To pull in the nose in plan view you need to apply ammonia on the 1/2" x 1/8" doubler and the surrounding fuselage sides, inside and out - I applied it using a brush and left it for 15 minutes to soften up. Using soft balsa blocks to load up against, bit by bit I pulled the nose into shape - pinching at F3, F2 and F1. I found I had to relieve the doublers a little around F1 for them to drop into the slots - effectively meaning the same former mod IS needed on F1 and applied to F2 and F3. No glue applied at this stage, the sides are just bent into shape whilst fully wetted out - it's left to dry out in this preloaded condition and glue will be applied tomorrow. Time for a Quote Link to comment Share on other sites More sharing options...
Alan Gorham_ Posted March 21, 2018 Share Posted March 21, 2018 Enjoying watching you put this together Phil. It's quite a novel design technique to me that Matt used. I would have tried wrapping the top deck in one piece of wood, making it fit down onto the fuselage sides. I like it and I like the "key" piece at the nose. Nice, different, unusual. Quote Link to comment Share on other sites More sharing options...
Harry Twist Posted March 22, 2018 Share Posted March 22, 2018 Great progress Phil - looking great, very detailed and informative. Making me feel guilty now - nearly finished a prior project then going to get my head around starting the Hurricane! Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 22, 2018 Author Share Posted March 22, 2018 Thanks Gents. Alan - yes there are a few novel features I guess and it makes for an interesting build. The second half of the fuselage build in particular relies on some sheet forming with ammonia and clamps being required once all the formers are correctly positioned. Harry - still plenty of time! - it builds quicker than the A-4 ever did - we look forward to seeing your blog develop! I've got a bit more done before work today. First thing I took the clamps off last nights ammonia soaked forward fuselage - it's worked well bar a little shrinkage of the forward fuselage side 'key' section - I used PVA for this joint - worth noting a water resistant bond would work better and perhaps stop this shrinkage when the ammonia is left to dry out. Anyway the clamps were removed and there was very little 'relaxation' in the assembly, it held easily with bands whilst the glue I applied cured. So that's the nose and tail pulled in correctly in plan view. Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 22, 2018 Author Share Posted March 22, 2018 I added some little hardwood bearers to the lite-ply servo plate and opened it up a little to accept a Savox servo for the elevator. When positioned up against F3 and the fuselage doubler I noticed the servo arm was sitting lower than the hole pre-drilled in F4 for the snake run - so I lowered the snake retention by gluing a small extension of lite-ply (taken from the centre of one of the other formers) to the front of F4. F4 was then glued in place onto the doublers only - the fuselage needs a little squeeze here to ensure the doublers are just brought round enough to sit into the slightly angled slots in the former. Do ensure that no glue oozes onto the remaining top edge of the former as this will restrict curvature at a later stage. Quote Link to comment Share on other sites More sharing options...
dirk tinck Posted March 22, 2018 Share Posted March 22, 2018 Following your build every day Phil,and it's a riddle to me how you keep everything so clean! I woudn't dare taking pic's of my building table ! With the april event coming up and two models to complete i will start the hurricane after. I hope i don't have to cut any structural parts of the fuse to go with the Russian version(open cockpits) Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 23, 2018 Author Share Posted March 23, 2018 Look forward to seeing you in a couple of weeks then Dirk! Great that you are flying with us again on the Orme!! With the fuselage joined and shaped front and back it was time to fit the rear formers F8 and F9. With the complications of vertical positioning created by the former notch and fuselage datum mods - I wanted to do all I could to ensure these 'floating' formers were positioned as accurately as possible. On Sheet 1 I drew a straight line representing the building board from the base of F3 to the base of F7 (as the model sits on the bench) and extended that rearwards to F9. Measurements from that datum to the underside of where the formers are drawn on sheet 1 were taken - 16mm for F8 and 35mm for F9. Balsa blocks were made up to this height, pinned to the plan with a centreline reference added for ease. The fuselage was then positioned over these blocks and chocked/pinned accurately over the centreline. Via dry fitting I found I had to notch out the pre cut doubler recesses on both formers by ~2mm on the lower edge. F8 and F9 were glued into position (again glue only applied on the lower half of the former to allow for fuselage curvature later) and the clamps were in use to give the fuselage an equal squeeze just where required. F8 is seen here sat on its height guiding block. Note the bottom of F8 protrudes lower than the fuselage side at this stage - it looks odd but it's ok as we still have to add the 3/4" triangular and it will all sand up just fine. F8 and F9 in place - I used gorilla glue sparingly on the joints, giving me plenty of time to fiddle everything into the exact position and orientation before it was left to dry overnight. Edited By Phil Cooke on 23/03/2018 12:16:10 Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 25, 2018 Author Share Posted March 25, 2018 I've fitted the 3/4" triangular section to the rear lower fuselage. In profile, this runs straight from F7 to F9, however in plan it requires some bending and shaping to enable it to fit into the recesses in the formers whilst taking the natural bow of the rear fuselage. I performed a number of hacksaw cuts at 1cm spacing to enable the curvature between F7 and F8. At the rear (in plan) it needs thinning down to zero so the two triangular sections meet directly on the centreline. You can see in the shot below the section sits fully engaged into the recesses in F8 and F9, sits flush with the fuselage side at F7 and overhangs by over 1/4" at the extreme rear. Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 26, 2018 Author Share Posted March 26, 2018 Sanding the 3/4" triangular section to the required 2D profile curve before the rear lower 5/16" balsa sheeting is added. Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 27, 2018 Author Share Posted March 27, 2018 Rear lower sheet added - 5/16" soft balsa. The fus is wider than the 4" stock at the wing saddle, so to maintain the grain running lengthwise (to aid shaping) two lengths of sheet were glued together with the join positioned right on the centreline. Rough sanded to plan view for now - there's quite a lot of material to come off this to form the Hurricane's characteristic hull - quite rounded at F8 yet very angular around the tailplane. Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted March 27, 2018 Author Share Posted March 27, 2018 Time to bend the lower front fuselage around F2. Ammonia is required here to enable the 1/8" balsa sides to take on the required profile, applied locally with a brush again, trying not to re-wet the key joint (which opened up before!) After 15 mins or so the wood was pliable enough to take the curve... I used medium cyano and kicker to 'grab' the fuselage side once it was rolled into position by hand, I then reinforced the joint from the rear with a good fillet of epoxy and micro-balloons. My fuselage suffered a little damage due to load at the corner of F3 - this was due to the pin-holes I'd created here locally when pinning the fus to the board - perforating the wood and making it weak - it was re-clamped and glued square against F3 The fuselage overhangs were trimmed straight awaiting final block sanding to allow the bottom sheeting to be fitted between F3 and F2 later. Edited By Phil Cooke on 27/03/2018 18:27:46 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.