Jump to content

1/24 scale Grumman F7F Tigercat N7654C


Recommended Posts

..and now for something mildly different...

I have been posting an experiment I have been doing over on LSP and thought now it seems it is not an abject failure I might share it here for anyone interested..

I wanted a change and to move projects around to do something I have literally always wanted - my all-time favourite aircraft is the Tigercat and despite years of waiting there is still no large scale injection moulded kit of it, so rather than wait any longer I am going to try and make one myself..

I thought about using the combat / ID 1/32 vacform but then thought why not go completely mad and try it in 1/24. The basis will be an upscaled Fly Models 1/33 card (yes, card) kit. I had it blown up by 37.5% to form the templates for a 1/24 version.

the engines will come from a 1/24 Kinetic P47 (copied in resin) which I will get once I prove to myself it's viable..

..such are dreams made of so we will see.. if it works out it opens the door to a whole world of LSPs not available in kit form, if it doesn't, it will be a pretty public failure, but hey, we don't know unless we try..

I haven't fully decided which airframe yet, but am not a great fan of GSB so likely this one - TBM Inc Tanker #E63 N7654C an F7F3. It's important the lines are not ruined by the large tank usually carried but thanks to Warbird Information Exchange I found these shots of it without it...

WIP11_zps0b93c2fe.jpg

..Card models are all new to me, so lets see what's in the 'kit'..

WIP01_zpsb0a6dd32.jpg

..exploded diagrams - ok can understand that...

WIP02_zpsc8307b9d.jpg

WIP04_zps396407d5.jpg

..assembly diagrams - check. seems straightforward...

WIP03_zps898aac10.jpg

..pattern parts - ok.. reminds me of the old balsa kits I had a bash at in the last century as a boy...

WIP05_zpsc5b69782.jpg

..WTF...

WIP06_zps6e189a2e.jpg

..oh boy - these are the skins - will have to use these as templates in plastic, maybe some sheet metal litho, rivet first or not - this is going to be a steep learning curve...

WIP07_zps7d6d62d0.jpg

..interior parts - think I will be fine with these :ninja:

WIP09_zps41ae21f7.jpg

..as if I was ever going to build two R2800's cylinder by cylinder - total respect for these card modellers...

WIP10_zpsa95c88cd.jpg

..so, we will see what happens - in my head I can crack on quite quickly with the fuselage as actually it's just about using the templates to create a 1mm plastic card substructure and then play around skinning it...

..so I got the printing back - I just had it copied in black & white and upscaled 137.5% to get from 1/33 to 1/24 scale - 3 copies of each sheet and the 3-view blown up to full scale cost me £24.50, plus the $30 for the 'kit' so comparable to a low end 1/32 kit (takes cover at this point...)

I had sheets of 1.5mm card and thought the main spar structural bulkheads should be this beefy stuff so started there - part 6a. I used a paper glue here in the UK called PrittStick to glue the paper template to the card...

WIP12_zpscb156898.jpg

..then I used a scalpel and steel rule to score the straight edges and where these met the curved fuselage section - a pair of pliers were used to bend and crack the plastic and lesson one was learnt where care is needed with such thick card not to have the break of the cut 'eat' into the part you are trying to make...

WIP13_zpsf146b54e.jpg

..ended up with a rough shape - my olfa cutter didn't like cutting through the paper & it tore the template a bit when cutting the circle in the middle, but did enough to leave a score line to work with...

WIP14_zpsdd4759f2.jpg

..I used a french curve to score the fuselage shape, but soon realised it was easier to do this freehand & break away the waste...

WIP15_zps61d21046.jpg

..out with the industrial tools - I used a home sander to finish the edges to the profile

WIP16_zpsc371e2cd.jpg

..I couldn't break out the circle in the middle so scored it and chain drilled a segment so I could get in with some small pliers & start breaking them out...

WIP17_zps520bbf15.jpg

..filed & sanded all the edges for a square finish...

WIP18_zpseb64771c.jpg

..I also scored the centreline of the part before peeling off the template, PrittStick doesn't seem to leave a residue so is ideal for the job...

WIP19_zpsb7b01ed9.jpg

..and there we have it - one part in about 20 - 25 minutes...

WIP20_zpse4cc94ea.jpg

only another few hundred days to go...

..so far all is going according to plan (ahem, for now)

..she is a big girl though - here is the plan with a six inch rule & a pot of tamiya paint

WIP21_zps7261bc6c.jpg

..I realised the little plastic stub wing spars on the part I made are going to be totally inadequate for two big wings with resin engines, so bulked up with brass square section - these are supposed to be bent forward on the card model to meet angled wing spars, but then I would not be able to slide the smaller square sections into them to mate the wings so have already deviated from the plans :whistle: I will have to engineer something later..

..as it is I bent the dihedral and masked up the part to avoid getting glue where I don't want it and epoxied it in place...

WIP28_zps4afea2fc.jpg

..I also went to my LHS for some plastic card as I am going to need quite a bit - unfortunately he only had 0.7mm which is pretty thick and 0.15 which is too thin to skin..

..I tried with a bit of 0.7mm as I want a solid structure, so first up was to stick the paper patterns down - the notched part is there to support one fuselage section meeting the next...

..as I was experimenting I decided to use the rivet pattern on the printout to add some & see if it was worthwhile. I also scored the white wing areas which proved to be a mistake as will be seen later...

WIP22_zps42e11db1.jpg

..got some thin card to make the joiner bit...

WIP23_zpsc4d3cc33.jpg

WIP24_zps60621dff.jpg

..no, it's not a Vulcan Bird of Prey, it's the part on my drafting pencil which seems to have the same radius as the bend I needed at the fuselage spine - I taped it on and tried holding it over a boiling kettle to heat the plastic & make the bend...

WIP25_zps61b88bb7.jpg

..it worked, but I have also been playing about just doing it cold over the edge of my workbench edge so will try that on the next part. I got a round handle and spent 10 mins trying to round the lower sections - thats when the scored wing parts cracked so won't be doing that again...

..it's starting to take it's final form and is very rigid so will take handling, sanding, shaping, scribing & riveting when all the sections come together (he says...)...

WIP26_zps1acd5554.jpg

WIP27_zps5b8f6156.jpg

..I also checked how it would mate to the next section with a dummy part - learnt it's likely not worth riveting as even as a guide it will be lost in final sanding - the butt joint looks like it will be pretty strong - I just wonder what using such thick skin will do to the pattern parts as they all assume the thickness of paper so stuff is likely to get out of whack from here...

WIP29_zps0f0968d5.jpg

..still - it's good fun, challenging and likely hugely over ambitious - but then I have always been a bit like that...

because paper is so thin, the pattern parts have tabs you would normally use to join them together, but as I am using 0.7mm plastic to skin the 'cat (and there is more than one way...) I need to add internal tabs like this one...

WIP30_zps82e7fb72.jpg

..the first skin went onto the former fine - I slotted it for the new brass spars too...

WIP32_zps32530581.jpg

..I also bulked up the inside faces to give more strength where the wings will meet - I may yet add more... you can see the bottom join is just taped so it would be flexible enough to close in the next section if I get anything wrong in making it - this turned out to be a good idea...

WIP31_zpsbc49c939.jpg

..onto the next section - this one joins at the fuselage spine and is quite a shape transition from the rounded top of the previous one - I also riveted it as I quite like the reference lines it gives and it only takes a minute while the part is flat..

..one thing I did try was pre-flexing the card. Before I stuck the paper pattern on, I pulled it backwards & forwards down over the edge of my bench - this made it much more flexible and saved messing about with heat & kettles...

WIP33_zps1a4f677b.jpg

..the finished parts - the funny shaped bit is a really clever template for joining the chine atop the fuselage - it allows a straight fold across a curve - hard to explain but maybe understood in a minute...

WIP34_zps45d47bfb.jpg

..assembling the former & skin - I used tape to hold it while spotting with CA - you can see the curved chine where that support part went at the top of the assembly..

WIP35_zpsa877511b.jpg

..not too shabby, but I ran a section of square stock in the gap & will refine it when I have all the sections together..

WIP36_zps0a08c1fc.jpg

so, first two sections complete - actually they are experimental and are really only a few hours work but I must admit I was worried they wouldn't fit together...

WIP37_zps3289205e.jpg

..YEY - success - glad I only taped the lower joint on the first section earlier as it helps easing them together to have this loose.. so I have a bit of 1/24 Tigercat fuselage...

WIP38_zps1677a482.jpg

WIP39_zps239ba127.jpg

..the theory seems to be working so far and I have to say it's an interesting excercise if I think about where I would be if I were planking a set of formers or something - this way sems to give more immediate results, but alignment may be a problem later on as there is no main known 'keel' or profile you build to

..another section added...

..it's started to get so big I had to get a bigger background..

WIP41_zpsf724258d.jpg

WIP40_zps13090aef.jpg

and where we are vs the plan...

WIP42_zpsd8124f7b.jpg

..I have glued all these sections together now and can see there are some issues starting to appear. The main one is some bulging where sections join as the skin bows in from the fuselage former until pushed out by the next one - I am not sure how I will cure this yet as it's not as simple as just sanding them down as I will soon go through the skin. I might start laminating some card on the sinkage areas ready for some industrial sanding later on...

WIP45_zps10812d88.jpg

..and here you can see the bulging - the spine also looks a bit wonky but I can straighten this out with some stock later on (he says...) - it's all assembled by eye so I am hoping I am not too way off on alignment...

WIP44_zpsc752071e.jpg

WIP43_zps9371c4cb.jpg

...these parts are basically all of the tail structure!... a sternpost for the rudder, a spar and two ribs for the tailplane (which is the span of a small 1/32 fighter) and a strengthener for the tailhook fitting - the rest is just skinning which may work in paper & card but is not going to cut it in plastic a few scales bigger...

WIP47_zpsbf391c4d.jpg

..I decided to move to the front while I thought about it and readied the next section which has the second wing spar...

WIP46_zpsa51f0bd1.jpg

...and that one joined the rest - alignment by eye again so don't be surprised if it turns out one wing low..

WIP49_zpsbd2f5cf5.jpg

WIP48_zps2a01c80b.jpg

WIP50_zpsdb482acf.jpg

..and with what little there is of the tail structure to give an idea an aeroplane will eventually emerge...

WIP51_zpsefa7eac9.jpg

WIP52_zps3322bbb0.jpg

..got another few sections roughed out and the more it comes together, the more I can see while I might have a vague outline, I don't have the smooth, sleek finish the real aircraft has, so I can see I will likely need to go down a car body filler route to fill the sinks between formers. I will also try filling it with that expanding foam stuff or something as I can see the filler cracking as it flexes - funny having a whole load of new problems to solve....

..anyways - this is where I am at - I haven't joined this section yet as I might just have the break here & carry on to the nosecone so I can fit out the cockpit in a while..

WIP56_zpsfba276e2.jpg

WIP55_zps83e16d5b.jpg

WIP53_zps7731c5ff.jpg

WIP54_zps52934712.jpg

..time to pause & do some thinking... need to work out the best way to get a base fuselage that will need a vac form nosecone, add the tail & stub spars for the stabilisers, get a lot of rough shaping work done so the whole thing is the right shape & in primer, but still be able to access the cockpit..

I am certainly having fun and I would say it has not been difficult so far - yes there are some little tricks I have learnt about pre-bending the skins, score & crack parts close to the line not try & sand to shape, use PrittStick and do not hang about for it to dry as the templates start to peel - but that is it

genuinely anyone could do this...

..first I decided I might cast the nose in resin, or at least make a solid part as this will be easier to form and more to the point, heavy..

..so, cut card profiles by tracing from the plan...

WIP57_zps691a5539.jpg

..cut out the wheel bay area and slotted one over the other - marked with a sharpie so I can see the profile and CA'd together...

WIP58_zps25e851e2.jpg

..offered it up and while it was a simple little stage, I feel very differently when I look at it - it looks like a Tigercat...

WIP60_zpsa1af5b05.jpg

WIP59_zps07c88b08.jpg

WIP61_zps0c1618fd.jpg

WIP62_zps77dc5405.jpg

WIP63_zpsd84b137a.jpg

I think I will fill it with that crazy foam stuff to hopefully stop any flexing.. though I tried some on a test piece but it is not very stable - the bubbles seem to big & uneven and it is still quite 'squishy' (technical term that is...), so I think I will get some proper stuff from Alec Tiranti

..I also roughly built up the nose on the 3D card template I made so I can rough sand it and ultimately refine it into a master to cast in resin. It's been a bit of a puzzle as I will need to sort out the nosewheel bay so will likely have to cut the resin nose in half laterally so I can rout out the bay as it should be just the aircraft skin and the bay roof...

..anyways, here it is looking pretty shonky for now...

WIP64_zps118c2473.jpg

..also started on the tail section - this framework is all there is in the card model so used it as a template...

WIP65_zps6c8f12e4.jpg

...this is the skin part and the one flimsy stabiliser spar - I marked where the spar should be and cut square holes for a brass stub replacement...

WIP66_zpseb4a7003.jpg

..so it will look like this...

WIP67_zps5df42028.jpg

..the skin resists being this shape so I taped it up to the formers ready to hold over a steaming kettle - the long brass tailspar is to ensure that the sternpost does not warp while I do it...

WIP68_zpsf77b0d4c.jpg

..after steaming the part I leave it in the fridge icebox to set the shape...

WIP69_zps6b7691a8.jpg

..now the part is pretty happily 'moulded' to it's final shape & contour..

WIP71_zps57785328.jpg

..I need to add more internal structure but this is roughly how it will look attached to the fuselage...

WIP72_zpsa5283836.jpg

WIP74_zpsedbe7544.jpg

WIP73_zpsaf70ed44.jpg

..getting there...

..after rough sanding away until I could see the formers, it looked like this...

WIP75_zps9d65f3cf.jpg

..I tacked it to the cockpit section with CA and protected that card construction with insulating tape to fill the nose shape to make the two match up...

WIP76_zps7fedffc4.jpg

..you can see where there are some small steps between the nose and cockpit that need fairing..

WIP78_zps6f9513b4.jpg

...and after addition of green stuff - I can sand to shape and not worry as the tape protects the cockpit section...

WIP79_zpsfeb913cb.jpg

WIP80_zpsd24ddfe3.jpg

..and after separating the parts and a first coat of primer...

WIP81_zpsb56e6700.jpg

..and it is ready to dry fit...

WIP83_zps9c3d906b.jpg

..the basic shape is starting to come together...

WIP82_zps9f9891ca.jpg

..I will finish this part as a master and cast a copy in resin so I can cut it in half and create the nose gear bay..

WIP84_zpsbc7aed1b.jpg

..I have pretty much got the nose master finished - I just haven't got enough Lego to build the box to put it in to get the mould made up - something I need to get sorted... just a bit of mr surfacer and a moulding plinth and it's done...

WIP85_zps58c12f22.jpg

..I also started on the tail section - this is where the rudder & tailplane spar are skinned, again using the card model template...

WIP86_zps1d016620.jpg

..also used the template to cut out a one piece fin/rudder skin and bent it over a kettle...

WIP88_zpsc0cdace9.jpg

..you can see how the funny tooth things help align the skins as they come together - I decided not to build up internal framework or more ribs etc, but to just experiment with skinning as is and filling with stabilising foam (thanks for the tip Iain)...

WIP89_zpsad813ea0.jpg

WIP90_zps9165d908.jpg

..mind you, it's all a bit 'wobbly' for now - hopefully I can correct any warpage when it is solid inside or by using heat again - at the moment it has some washout I didn't really want...

WIP91_zps2eb793a2.jpg

..the joins are amazing though - a testament to the original card design - I have had worse fits on Japanese kits!

WIP92_zps6ea4e9e6.jpg

..and the assembly taped to the airframe - I will cut out the rudder, make up the lower rudder skinning and build some internal strengthening but as a test it seems ok..

WIP93_zps9c613be7.jpg

..still loads to do - I want to get a primed fuselage with all the 'sagging' fixed in time for Telford (hopefully...)

WIP94_zps41d5e1dd.jpg

WIP95_zps939c2912.jpg

..so, that’s where I am at – sorry for the epic post but it is a few weeks work summarised into one ‘chapter’

...hope you enjoyed it, and yes, the men in white coats are on their way to my place to give me a check-up from the neck-up...

TTFN

Peter

  • Like 31
Link to post
Share on other sites

Absolutely stunning what a project!

Hope you have arranged hanger space for the finished airframe - looking forward to more of this project

Roger

Link to post
Share on other sites

Peter,

You are a genius sir ... :mike:

This is ASTOUNDING ... I am eager to see more .

AWESOME Start to another very fine epic build.

I feel privileged to be able to see and follow your amazing workmanship...

Way to Go. :thumbsup:

Edited by HOUSTON
Link to post
Share on other sites

Awesome. Just don't know how you managed to turn those flat card shapes into a 3d plastic plane.

Can't wait to see more, even in the flesh at telford.

Matt

Link to post
Share on other sites

Make room in the front row for the old guy (that's be me). And keep your hands off my popcorn, I can't watch this stupendous build and your hands at the same time! A 1:24 F7F - never thought I'd see the day!

Cheers,

Bill

Link to post
Share on other sites

In the sage words of Dizzee Rascal, this is 'Bonkers'....

And in a good way... I would love to see a 1/24 Hellcat and your post is definitely inspiring me....!

How much dark matter will you be using to keep it on it's nose-wheel?

cheers,

Chris

Edited by TempestV
Link to post
Share on other sites
  • 2 weeks later...

wow! thanks all for your kind comments :thumbsup:

Back with another instalment...

so, the story is I needed to fill the fuselage with foam to give a solid bed for sorting the sagging between formers and later on scribing / rivetting etc. I tried a test part with that expanding foam builders use, but it was too squishy so on Iains (32SIG) recommendation I got some of this stuff , which now I have used it I can say is perfect for the job (in the right hands, but more of that later) It sets absolutely rock hard but is still really light...

WIP96_zps14885da9.jpg

..I had already worked out I couldn't just pour it in slosh it around and let magic do the rest, so I cut some pour holes in the bottom of the fuselage to reach each section, with each section being open to the next, and being open at the tail I thought the stuff would just bubble out where it needed to...

WIP97_zps2f5b8177.jpg

I had masked the entire airframe as the tiny test mix I did showed me how sticky and hard the stuff got - I mixed some up and poured it into each section - this was a crazy moment watching it spewing out everywhere...

WIP98_zps0a60197d.jpg

...took it out of the box and realised it was hot to the touch so knew then heat and pressure was a bad thing to have together when working with thin sheet plastic ...

..thankfully most of the mess broke away and it unmasked fairly cleanly..

WIP99_zpscc44a9c7.jpg

..now I don't have any pics of what it looked like immediately afterwards, but suffice to say there were some pretty dramatic looking blisters bulging outwards and the entire structure looked like it had been inflated...

I pretty much thought I had ruined all my work and was pretty peeved... it turns out you need vent holes to let the stuff escape as the pour holes block up & it just keeps expanding inside

I ended up setting about it with a coarse grit electric home sander as at this stage I had nothing to lose - it still looks porky and I have lost quite a bit of skinning...

WIP101_zps9e9fa369.jpg

WIP100_zpsf3bfd979.jpg

..I tried to even out the lumps & bumps with little regard for what I did to the skin... you can see here where the foam has come through so in most places I slathered thick CA over these spots to see if I can create a new skin and add some strength back in..

WIP103_zpsbabe9ef6.jpg

..these blown areas are far more subtle than the big blisters - between formers it looks sort of 'inflated' - it's proving hard to even this out...

WIP104_zpsb52c1a54.jpg

..hard at it.. I decided as it needed so much shaping not to keep the nose section & the tail separate, but to just get it all stuck together so I have one big problem rather than three little ones .....I think I can cut the bit above where the Instrument Panel goes away later to slot in a cockpit assembly..

..the black tape at the nose is to try & preserve the profile I matched the nose casting to while hacking at the fuselage with a bloody great industrial sander...

WIP102_zps9b307b94.jpg

..overall, I can probably still recover the surfaces & skinning, but a far more worrying problem has become visible... I present bananaplane...

..you can see a clear deviation from the centreline along it's length - I will never know if this is because I assembled without a traditional keel / datum, or if the heat in the foam process caused a warp - either way it's a bit of a shocker...

WIP105_zps90708d91.jpg

..I decided to prime it to really get a sense of the shape and the skin defects... funnily enough some of the panel lines look like panel lines where sections have been joined... but as can be seen there is a long way to go...

WIP110_zpseb0308d2.jpg

WIP109_zps7123ce03.jpg

WIP106_zps85badded.jpg

WIP107_zps4b0ae20d.jpg

WIP111_zps29847419.jpg

WIP108_zps92696ca9.jpg

After some great advice over on LSP on how to correct the bent fuselage I cut some slots in the short side and played around with bits of card that I had mildly shaped along the side to be inserted to wedge the slots open and close up the bend..

I did bend and rough handle the fuselage trying to get the first & thickest one in at the point where the curve really started - it was a real heart in mouth moment as I really thought there would be a loud crack and I would have snapped the thing in half...

..I actually only needed these two wedges - the third made it bend too much so I just used card to fill the middle slot (it was quite surprising how much correction thin slots/wedges made)...

WIP113_zps16626408.jpg

..this is what it ended up like - not perfect but good enough for me to move on..

WIP114_zpsb12a5631.jpg

..also made up the rear tip of the fuselage as this was just shaped from the card template in one dimension - made a laminate block from some seriously hard plastic square stock sheathed with card...

WIP115_zps573f53e1.jpg

..rough cut to a loose shape..

WIP116_zpsa9b56fcd.jpg

..after some sanding..

WIP117_zpsf434b32e.jpg

..after more sanding (yawn...)

WIP118_zps077ac6b6.jpg

..by now the actual structure is made from many different elements - card, foam, filler, CA etc.. this worries me as I want a consistent surface to build on and detail - for example I drew a centreline on the lower fuselage when working on the tailpiece and my pencil went straight through the wafer thin skin in one place..

WIP121_zps3784212b.jpg

..it's looking pretty sorry at the moment, but getting the basic shape and surface right is the foundation on which this is either a 1/24 Tigercat or a cartoon...

WIP120_zpscd934de0.jpg

WIP119_zps2b0817f9.jpg

..still working on getting the fuselage ship shape - one of the things that has been bothering me is the uneven skinning around the rudder shroud - you can see here it is quite mis-shapen in places...

WIP123_zpseff1060b.jpg

..I decided to use some brass channel which would mean removing some of the skin to 'let in' the brass section and theoretically get a nice clean, strong, straight edge.

I only had a 'U' section rather than 'L' section to hand, so got my dremel and a cutting bit and roughly cut the 'U' in half...

WIP124_zps5fbe1451.jpg

..I cut back the skin and CA'd the brass in place - I also made a section to go inside to dress it a bit even though I expect it won't be seen..

WIP125_zps30ffea33.jpg

..slapped on some green stuff to fair it in...

WIP126_zps9b0199f9.jpg

...and shot some of the Halfords filler primer Iain recommended ..

WIP127_zps37d8e8d8.jpg

..it set me thinking that given the perfect finish needed for painting silver, I might be asking too much and maybe I should model a Glossy Sea Blue Tigercat so I can relax a little...

..first a coat of filler primer, followed by some thick mr surfacer for all the little pin-holes, dinks and rough bits...

WIP129_zpsa3020bde.jpg

WIP130_zps45c33664.jpg

..this is where the fuselage had to be cut and 'darts' put in to straighten it out..

WIP131_zps53accdaf.jpg

..ready for another coat...

WIP132_zps426f8750.jpg

..and this is where I am at I really must get some lego so I can cast the nose from the master..

WIP135_zpsf37d983b.jpg

WIP134_zps1356a0cc.jpg

WIP136_zps2f4d76b9.jpg

WIP137_zps2ec6a279.jpg

WIP138_zps35f73511.jpg

WIP133_zps2da4b815.jpg

..next up I think I might do the rudder...

thats it for now

TTFN

Peter

  • Like 12
Link to post
Share on other sites
  • 2 weeks later...

thanks for all the encouragement guys - keeps me very well motivated!

have been trying to figure out how to cast the nose - I have made a master from sheet plastic templates and household filler to 'bulk' it out. Trouble is it takes no account of the nosewheel bay, and worse still it is pretty unstable. In the weeks since I have made it, it has started bubbling the surface paint and blowing in places.

I figured rather than mess about any more I would just get on and cast it and worry about the surface finish when it's in resin. While toying with how to make a one piece mould and all the faff & hassle of trying to rout out the nosewheel bay, I realised I just need to cast it in two parts, with the roof of the bay as the mould split...

..so, I got some thick sheet and cut out a shape to drop the master into where the roof would be..

WIP139_zpsded471a7.jpg

..I also marked out the boundary of the mould with what I thought would let the mould be self supporting..

WIP140_zps45cd1fec.jpg

..to seal the part into the mould I used maskol painted on from below so it doesn't interfere with the moulded nose shape.. the plastic plate also sits on two brass beams to stop it from bending when the weight of the mould material goes in..

WIP141_zps44050bfd.jpg

..the bay roof is lower than the real one as I want as much weight in the nose as possible so a big hunk of resin should help..

WIP142_zps66f85202.jpg

..I made a simple box from sheet and secured it around the part with a couple of spots of CA and sealed the edges with plasticine..

WIP143_zps5a37af9b.jpg

..and finally with the mould poured - I needed to wait 24hrs for it to cure, then I will turn it over, take the bottom plate off and repeat the process.

WIP144_zps441d31e2.jpg

Once complete I can pour resin into each half-mould and theoretically suspend lead weights in the top half and some sort of removable blank in the bottom half so it's not solid and I can hollow and shape it for the nosewheel bay..

this is the bottom of the mould with the sheet removed...(ie the whole thing turned upside down..)

WIP145_zps86ffc1a8.jpg

..this now forms the bottom of the next part of the mould, and as you can see the seam line where the two parts will join is pretty clean which is a good thing..

WIP146_zps6388a7b4.jpg

..I now used a metal rod rolled along all the sides of the mould to separate it from the box it sits in, so I can slide the box up and re-use it for the next phase..

WIP147_zpsb516f9ed.jpg

..and here it is ready for the next pour - I used maskol to seal the edges and there is silicon release agent where the two moulds meet so I can separate them cleanly

WIP148_zps8b5edeef.jpg

..so, after all that a bit of actual modelling...

..I started on the rudder - laminated a spar and stuck a handle on it so I could shape it, also used a rubber band to hold the bottom fillet to get the angle right (gone are the days of working to the plan, now it is tailor made territory...)

WIP149_zps2203f13f.jpg

..worked hard at shaping it right to get even spacing & angles..

WIP150_zps7c4fa0e7.jpg

..ended up with the spar and also added a hinge point from heating a bit of tube and pressing it in - this is actually scale thickness, the Tigercat has a bloody great torque tube in the rudder post..

WIP151_zps0604b136.jpg

...did the same for the top of the rudder post and drilled a hole so it sat at the right height on the tube - again this is scale, there is a big gap between the bottom of the rudder and the fuselage fairing..

WIP152_zps43711faf.jpg

..eventually had the outer frame built up..

WIP153_zpsf0c157ab.jpg

..and left it having started to make a skinning template from an envelope - it needs more internal support, but I will likely skin it with sheet brass..

WIP154_zpsbf243525.jpg

I took the parts out of the mould and it all seems to have worked..

..first up, I took the box off...

WIP155_zps18db5948.jpg

..then (and this is the most nerve wracking bit), I separated the mould halves...

WIP156_zpsf103a4b1.jpg

..and finally removed the master..

WIP157_zps2a54f0ba.jpg

..what I ended up with are some nice sectional moulds which I can simply pour the resin into - this is the upper nose half which will carry the fishing weights - I will suspend them in here and pour in the resin so I should get a nice heavy casting...

WIP158_zpsc1bdf266.jpg

need to think about how to bond this part to the fuselage as it is going to be carrying quite a bit of weight - think epoxy like araldite should do it..

..it struck me I might be able to re-use the nose master to displace the resin and create the hollow lower half of the nose for the nosewheel bay, so I drilled some holes in it, put some rods through and carefully suspended it in the mould after pouring in the resin..

WIP159_zpseed3dcb6.jpg

..seemed to work - certainly the outer face looked ok..

WIP162_zps4a6c8b96.jpg

..and with a bit of cleaning up the inner face should look ok too..

WIP163_zps5516feb9.jpg

..on to the upper half of the nose - I got an 8oz fishing weight and heath robinson style suspended it in the mould...

WIP160_zps989ffcdf.jpg

..here you can see the resin starting to go off, entombing it forever.. (I hope...)

WIP161_zps6b03ef42.jpg

..and ultimately I am happy at how they turned out..

WIP165_zpse0db465f.jpg

..the lower half is thicker where I don't want it to be (where I need to cut out the aperture for the nosewheel doors) so may well try making another one

WIP166_zps8ea49872.jpg

..I drilled a load of holes in the mating faces and added a rod to try and share some of the load between the fuselage and what is now a pretty heavy nose part and glued them together with epoxy - not as clean a joint as I would have liked as the epoxy started to go off and I think some of the holes filled with air causing resistance - but it is lined up, and it is well stuck so will do...

WIP167_zps4d65d3d0.jpg

..all is not quite rosy though, the moulds or something somewhere was not quite level so the nosewheel roof is not completely flat as you look nose-on..

..and now a bit of finishing and planning..

..first getting the seam sorted - the nose weighs quite a bit now so this will take a lot of stress - it also makes the model quite hard to handle and with such a long way to go thats a bit of an issue..

..the fit turned out quite well in the end..

WIP168_zps8cc9da10.jpg

WIP169_zpsa2aaf710.jpg

..I also re-cast the lower nose by turning the master upside down and using the top of it to create the hollow - the wall thickness is now workable. I also marked out where the gear leg and retraction strut will go..

WIP173_zpsb044b49c.jpg

..and scaled up a plan with my markings on where various elements need to go..

WIP174_zps18077310.jpg

..and shot a bit of primer to see whats what..

WIP170_zps5479dbd9.jpg

WIP171_zps0d04b7fa.jpg

WIP172_zps1e057e0b.jpg

..the dilemma I now have is whether to attach the lower nose and get all the shaping right and do keyhole surgery to detail it inside, or add detail to the nosewheel bay while the parts are separate and risk damaging / reworking it as I add the lower half..

..one to ponder until next time..

TTFN

Peter

Edited by airscale
  • Like 8
Link to post
Share on other sites

Just great.Have no word...

:)

  • Like 1
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...