Peter Garsden Posted December 25, 2014 Share Posted December 25, 2014 Well the Andy Conway plan with lovely canopy has arrived. I have ordered th Phill Cooke spec wings from those nice people in Scotland - foam wings. Havepaid by BACS and everything is on its way. Phil has given me some good tips, so am all set to go really. What chance I will get to have a go over Christmas with the alll prevailing downward domestic pressure I don't know. I was a bit hesistant of doing a lost foam version when I saw the plan and shape, but figure that jets are such odd shapes that firbreglass and foam is easier and cheaper and quicker than balsa. I made an Alpha Jet this way and found it really good. Having leanred from that experience - too much resin - not scraping excess off and not having the right thickness of cloth all helped so this time it should be easier. I am hoping to form the jet pipes with fibreglass rather than plastic bottles so hope they won't be too heavy. I fancy the colourway of the prototype to be honest as it is white and red, rather than camouflage or grey or sand. Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted December 25, 2014 Share Posted December 25, 2014 Looking forward to this Peter Quote Link to comment Share on other sites More sharing options...
Andy Blackburn Posted December 25, 2014 Share Posted December 25, 2014 Hi Peter - I'd be really interested in seeing how you get on with a lost foam Tornado (epoxy or polyester resin?); also, I wonder how the weight will compare to a conventionally-built fuselage? Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted December 27, 2014 Author Share Posted December 27, 2014 Thanks for that comment Andy. I will be using epoxy resin not polyester as it leaves more room for setting time. Also I think that Epoxy is not quite so brittle. I have ordered loads of stuff from a supplier near us in Stoke on Trent called Easy Composites who are very good and have a lot of helpful tutorials on the site. As for weight I have not done a fair comparison. My Alpha Jet ended up heavier than recommended, but only because I used too much resin. I did not scrape off the excess like I should have done. I also used slightly heavier cloth than recommended. If you look at Paul Janssen's site, he says 1 layer of 100gm per sq m then 2 layers of 60gm. I have not been able to source any 60gm but have found some 80gm. Does anyone know where I can get 60gm? I made the mistake also of trying to make the nose out of glass which is quite tricky. Paul recommends a balsa nose. With the Tornado being so pointed, I will be following the plan and finishing the end of the fuselage roughly, then trimming and sanding square. I don't think that a fibreglass fuselage can ever compete with balsa but can come pretty close. Certainly my Voltij aerobatic slope soarer is quite thin and light yet strong. After all one needs momentum with slope soarers to give them speed. What convinced me was looking at the plan of the Tornado which quotes 17oz per sq foot wing loading, so it will never be a floater. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted December 27, 2014 Author Share Posted December 27, 2014 Meant to link the Paul Janssen site sorry - if you go to **LINK** and select "Building Methods" then you can read his argument a nd method as to which is best. It had me convinced anyway. It is a bit annoying that Paul, who is Belgian, writes English better than I do Quote Link to comment Share on other sites More sharing options...
Steve McLaren Posted January 11, 2015 Share Posted January 11, 2015 Hi Peter, Very interesting this. I fancy trying this at some time in the future. I've read the link to the Paul Janssen explanation of the method. He makes it sound quite straightforward - at least for simple fuselages - based on templates on the 2 sides, then templates top and bottom, and then sanding to the correct shape. But that doesn't look so easy for something like a tornado. I'm intrigued to see how you achieve such a complex shape in the foam. And then how easy it is to get the glass cloth to conform to some of those sharp angles? Have you started yet? Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 18, 2015 Author Share Posted January 18, 2015 About to start Steve - but flying today in the snow of the Peak District - will post a photo if I can as it will be glorious up there - though light winds, so may be cheeky and maiden my Mustang. I agree with the comment re complex shape of the Tornado. It is something I have mulled over. Phil has sent me a link to some pictures of the real thing, which has helped a lot. I think I have got it planned and sorted. It is just a big carve and sand job - not tricky. Blue Foam sands and cuts really easily - I use an Irwin Japanese saw with fine teeth which is brilliant for the job. To be honest it is the complications of the balsa build which has encouraged me to try lost foam. Having done it once, I agree with Paul. It is quicker and, arguably simpler. The worst bit is getting the foam out with Acetone, I cut all my hands on the sharp edges of the fibreglass. The Acetone then seeped into the cuts causing even more pain - you may remember cut fingers and nitromethane in the old control line days? Ring any bells for anyone? I know I should have used rubber gloves - my own stupid fault, but it would have cut them as well. The more fibreglassing I do, the better I get at it. I also made the mistake with the Alpha Jet of trying to brush it on instead of dabbing it. I have bought some foam brushes from the Works which I saw recommended in an RCM&E Article - l think they will work a treat and they were only £2 for about 15 of them. Can't find a link on the site. I found some by Googling https://www.google.co.uk/search?q=foam+brushes&ie=utf-8&oe=utf-8&gws_rd=cr&ei=fHi7VM3lMYHjUPObgPAG#q=foam+brushes&tbm=shop **LINK** The only bad thing about this method is that you can't make more than one as the mould gets destroyed in the process. I keep the templates which is the time consuming bit. The debate about weight and building light is that we usually fly in howling gails when you need to add ballast anyway. Heavy models fly quicker. I think it is different with power where it can seriously affect a landing. Edited By Peter Garsden on 18/01/2015 09:23:50 Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 18, 2015 Author Share Posted January 18, 2015 Well got about half an hour flying today as the mist rolled in from the West and engulfed us all. This is a photo of the Roaches showing the fog on its way as well as a view from the farm and Teggs Nose where LMMGA used to fly before they were banned by an officious warden. Edited By Peter Garsden on 18/01/2015 21:29:46 Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 18, 2015 Author Share Posted January 18, 2015 Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 20, 2015 Author Share Posted January 20, 2015 The foam wing have arrived from - believe it or not from www.foamwings.co.uk, which is a great name for people who make foam wings - it does what it says on the tin. They look very neat, and well made with leading edges already attached. Very pleased with them, and for 87 pounds not a bad deal Question Phil. The veneer goes right to the trailing edge, so what is the best way of cutting the ailerons out. Obviously the tips are just glued on as normal, and how are you going to face the leading edge so we can hinge them? Top hinge with a silicon join? Line with epoxy and microballoons? Edited By Peter Garsden on 20/01/2015 22:59:20 Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 20, 2015 Author Share Posted January 20, 2015 Also big thanks to Andy Conway whose re drawn formers have arrived drawn to the edges of the fuselage so they will fit inside my lost foam fuselage. Great job, and thank you. He has also sent me the incredibly ingenious drawings for the swing wing machinery. Very ingenious. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 20, 2015 Author Share Posted January 20, 2015 Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted January 20, 2015 Share Posted January 20, 2015 Pete - Have a look at Andy Blackburns Tornado F3 thread HERE on how to cut out the ailerons - hes completed that section nicely. You mark the wings up to show the aileron span and the required hinge line, then you offset that hinge line by 1/4" fore and aft (Andy's used 3/16th actually) - and its these 2 lines that you cut. then you can glue 3/16" T/E on the wing and 3/16" L/E on the aileron - this is then fine for whatever hinge you want to employ - conventional, mylar, cyano or top hinge - its up to you!!!! The beauty of building from a plan!! On the ends you offset by 1/8" to allow you to cap the ends of the control surfaces with balsa. Again, you can see this nicely in Andys photos. Spot on! Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 24, 2015 Author Share Posted January 24, 2015 Well, after much head scratching, humming and hawing, looking at Phil's very useful blog and studying form, I have finally made a start. I got the plans copied at Mail Box, so I can mess with one copy and have a clean one for reference when the other is on the bench. I then marked round the correct lines for my top and bottom templates. I am making the jets separately. I did them in a different triangle shape. Using my carbon paper, I have done a top view template for both the fuselage and jets. See my photos. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 24, 2015 Author Share Posted January 24, 2015 Here you can see the separate jets template laid alongside the fuselage. The jets will be an odd shape and will take into account also the wheel shapes below. As we have a paperless office at work, we don't need our old file covers anymore so I take them home and cut them up. Very handy. Quote Link to comment Share on other sites More sharing options...
Mark Kettle 1 Posted January 24, 2015 Share Posted January 24, 2015 Looking forward to this one developing Peter and how your going to do it. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 28, 2015 Author Share Posted January 28, 2015 OK OK Look I know it doesn't get much more exciting than this, but I have photographed not only the top view templates but also the side views for the fuselage and the jets. I am struggling to work out the exact shape, but I think it will turn out OK. If it ends up looking like a Spitfire then I will know I have gone wrong somewhere - as if it would, honestly. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 28, 2015 Author Share Posted January 28, 2015 I have done as advised ie cut out the hole for the wing and then taped it back into position. I was thinking that I would mark the position on the foam, melt out the hole then use it to cut out the shape, but in reality it is easier I think to cut out the shape with a dremmel when it is formed. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 30, 2015 Author Share Posted January 30, 2015 Good progress tonight. A hot foam night with the two hot wire cutters -a short one and long one. Me and Keith lined up the templates for the jets and the fuselage. I used the datum line for the fuselage to line up with a Sharpie marked line half way up the block, which we had to cut to size first with the long bow on maximum heat. The top template i lined up with a half way mark. Lots of set squares used. It was difficult because the block was not quite square but I think we are OK. After all it is a mould which i can sand to shape anyway, so nothing crucial apart from the line of the wing seat and the incidence, but at the end of the day it is an all moving tailplane anyway so it is all adjustable. We cut out the jets and did the top profile of the fuselage. We didn't line up the side profiles - for the weekend. We marked up the profiles with 1 to 35 inch marks and called out time as we were cutting in the same way as you do wings to stop the bow dragging. Only error was small - we hit a pin where it had come out sideways - we use pins to secure the template to the block of blue foam. You can see what we did in the pictures Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 30, 2015 Author Share Posted January 30, 2015 Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 30, 2015 Author Share Posted January 30, 2015 This shows the marking up of the top template of the fuselage Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 30, 2015 Author Share Posted January 30, 2015 This is the side template of the Jet ready for cutting with the hot wire Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 30, 2015 Author Share Posted January 30, 2015 And finally the jet cut out side and top. You have to be careful to line up a right and left hand version. I made that mistake with the Alpha Jet. Not this time. Still have to cut out the scoop at the bottom for the wheel housing. I will do that with my hot wire pen, which is a great tool made out of balsa wrapped in masking tape with two plug wire inserts and a length of nichrome wire you can use to cut out servo wells etc. More next time. Time for sleeping now. Quote Link to comment Share on other sites More sharing options...
Mark Kettle 1 Posted January 30, 2015 Share Posted January 30, 2015 Nice Peter. What glue will you use to attach the blocks to each other. Edited By Mark Kettle 1 on 30/01/2015 06:35:32 Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted January 30, 2015 Share Posted January 30, 2015 Nice work Pete, I think there are a few of us watching this one closely to see how the lost foam fibreglass fus compares to the conventionally built up one. Looking forward to seeing this develop. Quote Link to comment Share on other sites More sharing options...
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