Chris Barlow Posted April 23, 2016 Share Posted April 23, 2016 Tonight I finally got around to clearing the bench and starting my A4. I knew I wanted to produce a Skyhawk with the avionics "hump" so the search began for an appealing colour scheme to go with it. A search of the internet brought up this Skyhawk, s/n 160264 which was the 2,960th and last manufactured Skyhawk and was delivered on 27th February 1979. Along with some airframe modifications to Phil and Matts plan I will have to figure out a way to produce the graphics down each side, maybe water slides, but I will have lots of time to think about that before I have to do it. Quote Link to comment Share on other sites More sharing options...
Chris Barlow Posted April 23, 2016 Author Share Posted April 23, 2016 So first up was the fuselage. The sides were jointed and glued using the tape method, lines on the plan were extended and the dry sides marked and cut. The former positions were marked and the cut outs formed for the jet intakes. I then added the triangular stock to the sides and the wing seat doublers before cutting the wing seat in the sides using the doublers as a template. Whilst the sides were pinned to the bench to dry I assembled the battery box, cut the nose floor and assembled the box/nose assembly. By the time I had that together the sides were dry enough to start gluing in formers and wing bolt plate to one side. Before I knew it, it was 3am and time to get some sleep so that's as far as I have got today. Hopefully by Saturday night the fuselage will be together and I can start planning the extended nose and hump! Quote Link to comment Share on other sites More sharing options...
John F Posted April 23, 2016 Share Posted April 23, 2016 That does look good. It'll be an interesting to see how you "do the hump". Hope it goes well. Quote Link to comment Share on other sites More sharing options...
Lorenz Mueller Posted April 23, 2016 Share Posted April 23, 2016 This being an A-4M, you'd have to adjust the fin (easy) and either squint or change the canopy shape (not so easy). Nice paint scheme though, good luck Lorenz Quote Link to comment Share on other sites More sharing options...
Chris Barlow Posted April 23, 2016 Author Share Posted April 23, 2016 Thanks Lorenz, yes I'll be changing the fin and nose but not yet decided what to do about the canopy. I have been tempted to build a vac forming box for a while and this model might just be the reason to do it. I might just paint slightly outside the supplied canopy lines and get it halfway there! Thinking about the colour scheme I could cut a set of masks with my vinyl cutter and airbrush all the insignia on the sides, indeed I could cut masks and airbrush all of it. Just another idea. This afternoon I assembled the fuselage in the jig ready for gluing up. The cockpit sides were very reluctant to take on the new shape so had to be sprayed with ammonia for encouragement. Whilst I was at it I also sprayed the rear sides at F7 to ease the bending for the tail. The center line of the fuselage was lined up with one of the grid lines on the jig to ensure a straight build. F6 was also raised up 1/8" to ensure the nose floor sat flat on the jig base board. After leaving it to soak for a while I removed the clamps and glued up the tail first including the 1/4" top deck between F5 and F7. I then glued the cockpit sides with aliphatic leaving the top 1/4" clear for some thin cyano. The sides were then pulled in with finger pressure and cyano used to glue and clamp the top corners. The sides fell nicely onto F2 but were bowing off F3 so I used a couple of clothes pegs in reverse to push the sides onto the former. Quote Link to comment Share on other sites More sharing options...
Andy Meade Posted April 25, 2016 Share Posted April 25, 2016 Nice progress Chris, and a lovely scheme to choose too Quote Link to comment Share on other sites More sharing options...
Lindsay Todd Posted April 25, 2016 Share Posted April 25, 2016 Nice one Chris, must admit I am very close to committing to this mass build but I fear other projects would get in the way but watching with interest for sure. Linds Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted April 25, 2016 Share Posted April 25, 2016 Excellent start Chris. Will be watching with interest. Canopy solution - get one from Traplet. Decal solution - get Tim at Model Markings to do them for you. Not worth all the hassle for £10. I am doing the same hump on my Israeli Air Force version. I am going to do it out of blue foam. I am also going to add some padding at the rear around the fin to make it more blended than as per the design. Might do that out of foam also. Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted April 25, 2016 Share Posted April 25, 2016 Good progress Chris - going together very nicely! I do hope you decide to take part and join in the fun Lindsay! A great excuse for another weekend out with us on the Orme in September! Pete - the canopy concern is that the Traplet one made from my plug is modelled on the earlier variants B to F. For the A-4M model, as being modelled here by Chris, the pilots visibility was improved via a modified canopy - slightly more 'bulbous' and with revised canopy framing - more glass/less metal basically. Of course you could just fit the standard Traplet moulding, but the 'Gods of Slope Scale' wouldn't be at all happy and they would surely send us light South Easterly winds during our September weekend Quote Link to comment Share on other sites More sharing options...
Chris Barlow Posted May 15, 2016 Author Share Posted May 15, 2016 A slight delay in proceedings due to some better weather and some nice powered flying at last! I now have 2 building benches! One outside for repairs and servicing and my bench in the shed for full builds so should be getting back to it this week! Better get my finger out! Linds, the PSS builds are interesting as I've come across some design and building methods I've not seen in i.c builds before. I suspect it's because the PSS models have to be strong for landings (diching) but still light. It's definitely expanded my building techniques. As for the flying, well I'm still learning that! It helps to have a mate ? nagging you to throw your new models off a cliff over the sea claiming "It'll be fine" (Peter) Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted May 16, 2016 Share Posted May 16, 2016 LOL - wish I could help you take the plunge and throw them off for you with my hands on the sticks but you fly Mode 2 and me Mode 1 - there are lots of others however who will do that for you. You just have to have faith that models will stay up in the air on slope lift and not crash and burn into the sea below! Quote Link to comment Share on other sites More sharing options...
Chris Barlow Posted July 11, 2016 Author Share Posted July 11, 2016 Thanks Peter! It would help if I didn't have to maiden them by throwing them out over the sea each time too! A maiden over land would be nicer! Back early(ish) from Greenacres and with several models still in the caravan there's a bit more space in the shed so the Corsair was relegated to the fuselage rack whilst waiting for a new cowl and the bench cleared ready for a dedicated re-start on the last Skyhawk! OK almost all of the Corsair cleared off the bench! There's a scuff I still need to polish off the canopy! Quote Link to comment Share on other sites More sharing options...
Chris Barlow Posted July 18, 2016 Author Share Posted July 18, 2016 Managed a bit of time on the A4 this week but not many photographs! The decking is complete with the nose built up and shaped. The intake pods are also complete. I made an electronics hump from 1/8 balsa and 1/4 triangle stock. I've also made the rearmost part of the canopy structure from laminations of 1/2" balsa since it will be connected to the hump. Still need some more accurate shaping but it's getting there. I'm using a 1/72 plastic model and 3 view drawings to help with the shapes and proportions. This is the inside of the electronics hump. Started off like a canoe! I've also modified the fin and rudder to an A-4M and added the tail plane and supports. Got a little help from this fella who sat quietly on the rudder whilst I jigged and checked the tailplane was square! I have yet to make a start on the canopy though. I have an understanding of the different shape from Phils origional and will either vac form my own or shrink a pop bottle over a wooden plug. I've not decided yet! Sorry it's a very brief update but between servicing and repairing airframes, work, family life and flying time is quite short! Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted July 18, 2016 Share Posted July 18, 2016 No apologies needed Chris, that's a great update! Good to see another variant coming to life with all it's little tweaks from the original drawing! Quote Link to comment Share on other sites More sharing options...
John H. Rood Posted July 18, 2016 Share Posted July 18, 2016 WOW! Great stuff... this whole mass build just gets more and more fun. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted July 19, 2016 Share Posted July 19, 2016 A Muth? Give it to Inspector Clueso. He has probably eaten most of the fin by now (the moth that is not Clueso) Quote Link to comment Share on other sites More sharing options...
Chris Barlow Posted July 19, 2016 Author Share Posted July 19, 2016 It's a new lightening technique Peter! I'm trying wood worm for the wings. Quote Link to comment Share on other sites More sharing options...
Steve Houghton Posted July 19, 2016 Share Posted July 19, 2016 A good looking build, Chris. Keep us informed of your approach to canopy moulding - it's always useful to see how builders tackle this. Quote Link to comment Share on other sites More sharing options...
McG 6969 Posted July 20, 2016 Share Posted July 20, 2016 Hi Chris, Aren't the wings too much of a labyrinth for 'untrained' wood worms??? ... Hakuna matata Chris BRU - BE / CTR Worms Control Quote Link to comment Share on other sites More sharing options...
Chris Barlow Posted July 22, 2016 Author Share Posted July 22, 2016 Posted by Steve Houghton on 19/07/2016 23:36:27: A good looking build, Chris. Keep us informed of your approach to canopy moulding - it's always useful to see how builders tackle this. Will do Steve. I suspect it's going to be a pop bottle shrunk over a plug due to time constraints! Time for another quick update. Due to a developing tight schedule I have decided to cover the A4 with film. I was going to go with glass cloth and epoxy resin with a sprayed finish but that can get quite heavy and knowing me I get way too involved in it and it'll take a lot of time. So whilst at Cosford I picked up a couple of rolls of OraCover. Using film presents it's own problem though. As I've made the ribbed rudder covering it isn't going to be easy so I wanted to have a go at it to see if I was going to have to glass and spray the whole fin instead! Now I don't mean to teaching anyone how to suck eggs but for any body out there who wants a ribbed rudder and also wants to cover with film but doesn't think they can do it, you can! I started with a 1" wide strip of covering and tacked one edge to the bottom of the lowest rib then turning the iron over 90 degrees I I fixed the film to the top edge of the rib I then put a tiny cut in the bottom corner where the fin meets the body of the rudder and ironed the recessed flat between the ribs Another tiny cut where the underside of the next rib meets the rudder body and then I ironed the remaining two edges inside the recess The leading edge was then lightly tacked down With a very sharp blade I cut the leading edge of the covering 1/8 " from the recess The covering was then ironed onto the raised flat of the rib above which was then trimmed flush with a sharp blade and the trailing edge ironed around the back of the rudder and trimmed flush Then I started again with another strip, starting by tacking to the last rib covered and so on until all the ribs and recessed were covered. I then went over the film with the iron slightly hotter and ironed out all the wrinkles I could. It's not 100% perfect (nothing is ever perfect) but at 50' and 40 mph you'll not see the blemishes! And the other side That took around 2 hours for each side! Whilst the iron was still hot I covered the rest of the tail assembly too Now I just need to fine sand the fuselage and get that covered then I can build the wing! Quote Link to comment Share on other sites More sharing options...
Piers Bowlan Posted July 22, 2016 Share Posted July 22, 2016 Wow, that is impressive Chris. I was thinking about a poly-c finish and paint for mine but I would rather use film so now I will give it a go but I don't think it will turn out as neat as yours. I have built the Fuz and now about to make the fin and rudder so this is good timing. Also, what adhesive did you use on your modified rudder, by the way? Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted July 22, 2016 Share Posted July 22, 2016 Impressive ironing skills Chris! That looks superb!! Quote Link to comment Share on other sites More sharing options...
Steve Houghton Posted July 22, 2016 Share Posted July 22, 2016 Yes, an object lesson in applying film to awkward places. I've been contemplating this process and may use a similar approach. My problem is that the tip of my iron has cracked off so that it's now blunt - time for a new iron, perhaps! Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted July 23, 2016 Share Posted July 23, 2016 Deep respect Chris on ironing techniques. I did look at the rudder and decided there was no way I was going to attempt film myself, which is why I went for paint. I suppose I just don't have as much patience which is why I am already finished I suppose but hey ho. Quote Link to comment Share on other sites More sharing options...
Chris Barlow Posted August 1, 2016 Author Share Posted August 1, 2016 A bit more progress this week, Might be in with a good chance of finishing on time yet! Piers, I pinned the ribs in place to line them up and used super phatic with a fine nozzel to wick into the balsa and glue them. Steve, good excuse for new toys tools there, treat yourself! Peter, that just about sums up my biggest problem when building. I can stick the wood together quite quickly but often get too involved in the detail and finishing which drags it out a lot. Hopefully I won't get too carried away with this one! I have now stuck the wing together and have gone for dual servos with torque rods. I would like to have a centre line drop tank and had to give some thought on how to release it before landing. As it's on the centre line it's now so easy to use a push rod through a guide so I have come up with a simple alternative. I have made a notched cutout in each of the centre ribs which when joined will make a 1/8" slot. I then made a servo mount on one side of the rib which will simply rotate the servo horn through a slot in the ribs and engage in a slot cut into the pylon for the drop tank. I hope the pictures make more sense? I used the useless ply spar which was too short in height as a doubler for the centre ribs to strengthen them. If for any reason the tank doesn't drop at least it'll stand a chance of landing on the tank without ripping out the ribs from the wing! Quote Link to comment Share on other sites More sharing options...
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