Peter Garsden Posted December 2, 2019 Author Share Posted December 2, 2019 Thought I would show you the extra 1.5mm sheet needed to pack up R1A on the jig I read about it and wondered what was needed. I found that the jig went together a bit twisted (inevitable) so needed securing down. I am making both wings at once but even so it needs packing. Also make sure that you put some of the jig cross pieces (J7) in particular the right way round as there is a right and left hand version - mine turned out very warped at first until I checked. Edited By Peter Garsden on 02/12/2019 09:41:42 Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted December 2, 2019 Author Share Posted December 2, 2019 As I don't have a collection of weights just the right size, and because I wanted to make sure the bottom sheeting was flush with the jig, I pinned my bottom sheeting down. Very easy because the lines for ribs have ply underneath. When the ribs go on of course it will be pushed into place but even so...I wasn't convinced that weight alone would bed it down properly. You can see that I have used my handy engineering squares to line up each rib then pin it - invaluable. I am using Super Phatic. It is the best for ribs as it dries fast and fills the joints. Thin Cyano just goes everywhere. I tried cyano for one spar but it lifted in places. Not good for spruce. I am using spruce because it will produce a stiffer and therefore faster wing. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted December 2, 2019 Author Share Posted December 2, 2019 I think I have found an important cutting error. All the ribs are about 3mm too long at the leading edge even accounting for extra needed for the swept back wing. Martin am I correct? Suggest you cut them down before laying as it is much easier. Quote Link to comment Share on other sites More sharing options...
Martyn K Posted December 2, 2019 Share Posted December 2, 2019 Peter Is that 3mm to allow for the tapering of the LE (and TE) to accomodate the sweepback? Martyn Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted December 2, 2019 Author Share Posted December 2, 2019 Posted by Martyn K on 02/12/2019 10:06:20: Peter Is that 3mm to allow for the tapering of the LE (and TE) to accomodate the sweepback? Martyn No Martyn, it isn't. 3mm too long. The ribs as cut overlay the front false leading edge IMHO. If you look carefully at my picture it should speak for itself. The point you make was what I initially thought. Edited By Peter Garsden on 02/12/2019 11:30:27 Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted December 2, 2019 Author Share Posted December 2, 2019 I am going to try flaps, never done that on a PSS model before. I am using slightly stronger Savox servos for flaps and cheap Emax Metal Digitals (about £7) for the ailerons. This is the way I am fitting the servos. I have marked the lines with pin holes which I will remove when I take the wing off the jig. I am going to screw them to the triangular corners from the bottom. I am going to raise the servo on 3mm plinths so that the wire can run from bottom to top direct to the horn from inside the wing. There is enough room. It is important to glue these in position before you attach the ribs as the ply runs under the ribs and slots have to cut to make room. Edited By Peter Garsden on 02/12/2019 17:34:31 Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted December 8, 2019 Author Share Posted December 8, 2019 Change of plan. It will not work sticking the servos to the bottom surface of the wing if the control rod is going to exit the wing from the top surface because you will simply not be able to access the rod for adjustment. As this is going to be the mouldie type of linkage the servo has to attach to the top sheeting of the wing in order to give the correct angle for the rod, and allow adjustment. So I am going to glue a 1.5mm ply plate to the top sheeting and glue the servo to it. Hopefully that will work and there won't be too much play. Wires must thread in before top sheeting goes on. Note the loop of wire to give some play in case the servo needs to come out. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted December 23, 2019 Author Share Posted December 23, 2019 Yet another change of plan. Having seen Dirk's servo mounting, I decided to adopt it as it will, at least, be removable more easily. It has taken ages to make the mounts and the supports. You can see the way the rod will attach to the servo horn and emerge out of the top sheeting Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted December 23, 2019 Author Share Posted December 23, 2019 Yet another change of plan. Having seen Dirk's servo mounting, I decided to adopt it as it will, at least, be removable more easily. It has taken ages to make the mounts and the supports. You can see the way the rod will attach to the servo horn and emerge out of the top sheeting Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted December 23, 2019 Author Share Posted December 23, 2019 Too many times I have built a mouldie and not tested the position of the servo centers before gluing in the servos, This was made more difficult because I had soldered extension leads to the servos, and thus had no plugs to test the servos. I decided to use 1 Multiplex plug for all 4 servos with all 4 positive wires on the outside pin and all the negative on the other with the signal wires soldered to the remaining 4 pins. Much easier to assemble. I attached the receiver, and tested both the direction of the servos, and the centering before glueing the brackets to the wing supports. Shown below is the 1/32" ply strip to hold the servo in position underneath Edited By Peter Garsden on 23/12/2019 21:57:25 Quote Link to comment Share on other sites More sharing options...
dirk tinck Posted December 24, 2019 Share Posted December 24, 2019 Industrional espionage !! Are you really a lawyer ???? Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted December 24, 2019 Author Share Posted December 24, 2019 I will have to consult my intellectual property lawyers about my recently registered patent Dirk. I think espionage is a bit strong. Plagiarism would be a better word, but in view of the fact that we are not selling for profit and this is only for personal use, I think I probably have a defence. We will convene a court on the Hill of Orme. I will try to persuade my good friend Phil Cooke to judge. He is very fair. I will file papers in advance of course Oh, and I need to warn you that I will also be copying your speed brake mechanism, so you might as well apply for an injunction dans the Court of Belgium n'est-ce pas? Edited By Peter Garsden on 24/12/2019 15:52:08 Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted December 27, 2019 Author Share Posted December 27, 2019 Finally, after a lot of fiddling with servos, covers brackets etc, I have managed to glue in the servo supports with the covers on, and attach the top sheeting with aliphatic and a lorra lorra pins, as Cilla would say. Also attached the leading edge (not pictured) but fascinating none the less Quote Link to comment Share on other sites More sharing options...
McG 6969 Posted December 27, 2019 Share Posted December 27, 2019 Great progress, Peter. I'm still 'nowhere' with my wing(s). But slowly progressing with my Dog fuselage modifications... Is it me or are we nearly the only ones still progressing or at least 'posting' our efforts? Quite a bit of the 'early' Sabre builds seemed to have stalled recently? Cheers Chris Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 4, 2020 Author Share Posted January 4, 2020 Everyone seems to be building today. I have cut out some templates for my lost foam mould This is the top view of the fuselage, which Gordon very kindly produced in pdf form. I had to fold it over and cut out the other half then glue it to the cardboard, which was no problem. Even more kind was the drawing of side template which I will use to make sure the foam mould is the right shape before covering in fibreglass Quote Link to comment Share on other sites More sharing options...
John H. Rood Posted January 4, 2020 Share Posted January 4, 2020 Peter, once again I shall crawl on my belly down the alabaster tiles of my aeromodelling HALL OF SHAME... another unfinished project... this one here is a bogey in 1/10th scale ... I pollute your thread here because this MiG-15 has her nice portly fuselage constructed via the LOST FOAM process. I designed her in another lifetime, never finished her, and/but/however now I feel I just might need to raise the stakes for all these F-86 Sabres on zee rise... Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 5, 2020 Author Share Posted January 5, 2020 Interesting John. Fibreglass has been around for a long time. Not many people attempt it but I think it is quicker and easier than planking. A round fuselage lends itself well. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 16, 2020 Author Share Posted January 16, 2020 Well, with the wing finished attention had to be paid to the fuselage. I had cut out my side and top and bottom cardboard templates ready for cutting out the blue foam block with my hot wire cutter. When I came to assemble it I realised that I did not have enough foam so tried to cobble together sheets from bits - which was a bloody mess if I am honest, so I invested in some new pieces of under floor radiator sheet of the right size - not easy to get now - I found it on Amazon and this is the URL if you need any - **LINK** - there seemed to be a lot of small sheets used for dolls houses but nothing thick or big enough. Anyway I glued it together and Keith and I cut the block to size last night. You can see that I marked the position of the formers so I can match up my templates with the sides at the appropriate point to ensure I get the correct shape to the fuselage. I have both outside and inside profiles which are working well - thanks to Gordon for putting them on the special top view plan he did for me. These are the tools I use - a Japanese type fine toothed pull saw made by Irwin - great for cutting foam and a coarse permagrit file. I was able to draw the shape at F1 on the front of the fuselage to give me a good start. This will of course form the template for the lost foam mould which will be wrapped with parcel tape then fibreglass before dissolving it out of the middle with acetone. Quote Link to comment Share on other sites More sharing options...
dirk tinck Posted January 17, 2020 Share Posted January 17, 2020 Nice going Pete ! Are you making two halves here ? I would like to try this someday!! I'm following ! Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 17, 2020 Author Share Posted January 17, 2020 Posted by dirk tinck on 17/01/2020 00:22:08: Nice going Pete ! Are you making two halves here ? I would like to try this someday!! I'm following ! No, I'm not making 2 halves. I have done a full run through of the procedure on my Tornado blog as that is also fibreglass. I am using your fellow Belgian chap's process, can't remember his name now of lost foam (Paul Janssen I think), so the steps are:- Do a cardboard template for top and side view. Pin it to a block of blue foam or the equivalent - has to be firm so it can be sanded. Cut out top and side views with a hot wire (you need a mate to help with this). Carve out the shape from the block. This fuselage is bigger than what I have attempted before and it was taking ages manually, so I have used my Bosch Shoe Sander which is working well. I am using side templates as you can see. Wrap the block in brown parcel tape - I use an iron to flatten it and help it adhere at about 100 degrees C to avoid melting. Cover the parcel tape with wax Apply spray contact adhesive to hold the first layer of 150 gram fibreglass and soak with epoxy resin - I use laminating. It is quicker to use polyester but I find it dries too fast. I also put in some reinforcing strips of carbon and kevlar in stressed areas. Let it dry then apply a second coat of 150 gram. I have used peel ply to cover the fibreglass but it is a bit difficult to get it to adhere. It does soak up any excess resin well. Final layer of 80 gram Paint on a layers of microballoons and epoxy then sand down for a smooth finish. Cut a hole under the wing and pour in acetate. You can pull out the goo with the parcel tape. I usually make holes in the foam to pour the acetone into. This is the worst bit. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 17, 2020 Author Share Posted January 17, 2020 The formers helped a lot as did the shoe horn sander. I used both rough and flne pads Quote Link to comment Share on other sites More sharing options...
Chris Barlow Posted January 19, 2020 Share Posted January 19, 2020 That's a fine looking sculpture there Pete. It's a shame to melt it down into goo! How do you deal with the blue foam sanding dust? I have only used it in small amounts and the dust is horrible! Sticks to everything through static and clogs the vacuum filters up very quickly! Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 19, 2020 Author Share Posted January 19, 2020 The Dust - that is the thing according to "Dark Materials" that children don't have which adults do and is responsible for all evil deeds, but I digress. Yes it gets everywhere but I am using a shoe horn sander which has a dust collection bin. That helps a lot. As for vacuuming up we have a Kirby which vacuums up small children it is so powerful. Well I have finalised my shape which fits the templates and finished it off with some foam sanding sheets to follow the curves. Also started to apply some parcel tape with the film iron set at 125 degrees C which seems fine. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 19, 2020 Author Share Posted January 19, 2020 Well I have cut out and attached with the contact adhesive (foam friendly) 3M 77 which I have used before but is running low, all the pieces of the first layer of fibreglass ie 150 gram per square metre together with some reinforcement from a 2 inch carbon bandage, some 150 gram kevlar for the nose (signal friendly), and some carbon tape down to the tail. Not the bbq skewer type arrangement to support the fuselage, which are pieces of wood and lengths of thick wire with a point ground into it. They clamp to the bench at one end and screw to the end of the bench at the other. The fibreglass will overlap at the end then be cut off. I use the templates to cut out the cloth This is ready for dousing with resin. I have overlaid but not pictured the reinforcement carbon and kevlar. Edited By Peter Garsden on 19/01/2020 19:23:47 Quote Link to comment Share on other sites More sharing options...
Steve McLaren Posted January 19, 2020 Share Posted January 19, 2020 Very interesting Pete. Do you put all the fibreglass layers on now in this dry state? And do you vacuum bag the whole thing when you add the resin? Quote Link to comment Share on other sites More sharing options...
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