Peter Garsden Posted December 30, 2015 Author Share Posted December 30, 2015 Next is the bit I hate - dissolving the foam with Acetone. Last time I did this, I ran out of Acetone and tried to remelt it, but that doesn't work a 2nd time, so it all has to be done in one go, so I bought a 5 litre container of Acetone to make sure. Worked a treat, and this time, no sharp edges to cut me. The long sausage of parcel tape pulled out a treat and I now have a hollow much lighter fuselage Quote Link to comment Share on other sites More sharing options...
Chris Barlow Posted December 30, 2015 Share Posted December 30, 2015 Looks very clean and tidy in there Peter. When you wrote "This time I didn't cut myself" I winced imagining a cut on glass fibre and acetone! What is the average thickness of the GF shell? Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 2, 2016 Author Share Posted January 2, 2016 The average thickness Chris according to the micrometer is 1 to 1.5mm. Have now reinforced the fin with a 6mm spar up the middle, in the edge and bottom of the rudder, which I have detached and hinged with mylar, and glued a 3mm ply base for the tailplane, with a 4mm nut underneath so I can clamp the tailplane to the support afforded by the fin. Works well. I will put a 3mm carbon pin to help stabilise the side movement of the tailplane. It's finally looking more like an airplane. All left to do now is install the wing tubes and I'm not looking forward to that as it is millimetre critical Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 3, 2016 Author Share Posted January 3, 2016 The next bit is the one I had been dreading - making the holes for the tubes which take the 2 10mm carbon rods. Any slight error and the wings won't fit. I decided that I should make some fairing to hold the tubes. I looked at the other mouldies and the fairing seem to protrude by about 3/16". So I decided to use 2 pieces of 1/8" ply glued together with Aliphatic Resin. Unfortunately it warped when drying. I then glued it to the side of the fuselage with resin before marking up the holes for the wing tubes. I started by drilling 5mm holes then lining up a carbon tube to make sure it was in line. I lined up the templates either side of the fuselage and marked the holes. I used the pillar drill to make sure it was in line. It was tricky. I think one of the holes is out of line, and will have to be redone. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 3, 2016 Author Share Posted January 3, 2016 The next bit is the one I had been dreading - making the holes for the tubes which take the 2 10mm carbon rods. Any slight error and the wings won't fit. I decided that I should make some fairing to hold the tubes. I looked at the other mouldies and the fairing seem to protrude by about 3/16". So I decided to use 2 pieces of 1/8" ply glued together with Aliphatic Resin. Unfortunately it warped when drying. I then glued it to the side of the fuselage with resin before marking up the holes for the wing tubes. I started by drilling 5mm holes then lining up a carbon tube to make sure it was in line. I lined up the templates either side of the fuselage and marked the holes. I used the pillar drill to make sure it was in line. It was tricky. I think one of the holes is out of line, and will have to be redone. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 31, 2016 Author Share Posted January 31, 2016 Have been away for 2 weeks without any progress, I did try to assemble the Jart which looks more like the finished thing . Still quite a lot to do - fix ballast tube and servo tray, line the inside of the fuselage with fibreglass to hold the canopy in place, fix the fin and tail plane, and cover. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted January 31, 2016 Author Share Posted January 31, 2016 Installed a 2nd plane Savox servo and when I tried it, just buzzed and didn't move - motor was very hot and has gone, so have replaced it with another. It was in my Willow F3F when it plunged into the earth due a faulty battery at Mach 3, so no wonder. Have struggle to get enough clearance for the rudder control rod. I have used a very good brass close fitting from RC Metal Bitz, I had knocking around. I have had to file down the M2 metal clevis, Nearly there now. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted February 9, 2016 Author Share Posted February 9, 2016 I have made the two 1/8 inch ply plates for inside the fuselage, front and back. The back one holds the ballast tube, so I cut a hole in the middle to take the tube, then tack glued it in position whilst I overlaid some fibreglass bandage to hold the tube in position and form a cradle. First I greased the tube with wax so it can be removed afterwards then epoxied in position. The front plate will be bolted to the back plate so it is removable and will house the battery and the receiver and place them up the front of the fuselage. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted February 9, 2016 Author Share Posted February 9, 2016 I have made the two 1/8 inch ply plates for inside the fuselage, front and back. The back one holds the ballast tube, so I cut a hole in the middle to take the tube, then tack glued it in position whilst I overlaid some fibreglass bandage to hold the tube in position and form a cradle. First I greased the tube with wax so it can be removed afterwards then epoxied in position. The front plate will be bolted to the back plate so it is removable and will house the battery and the receiver and place them up the front of the fuselage. I put two layers of fibreglass cloth then lay some strips of carbon tow down the outside of the plate to add strength as I had some epoxy left over. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted February 12, 2016 Author Share Posted February 12, 2016 I needed to trim the 1/8th ply wing fairings at an angle so that the root fitted flush with the fuselage. I already have an Irwin Japanese saw which I use for blue foam but it is a little too coarse, and my balsa saw is too fine, so I invested in a Zona Flush Cut saw from Traplet. It is excellent and can be used to cut hardwood. I have already had my money's worth from it. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted February 12, 2016 Author Share Posted February 12, 2016 I decided to use a Hitec 85MG for the elevator servo, which is micro in size but has bags of torque. Despite the wide servo tray, there isn't a lot of room for it between the Ballast Tube, and the 1/4 square balsa I am going to use to provide more gluing area as a support. The problem is with lost foam you are always working from the inside out rather than vica versa. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted February 12, 2016 Author Share Posted February 12, 2016 Next step is to prepare the leads for the multiplex plugs in order to make sure they won't foul the elevator servo. and the front ply plate cut out for the battery with slots cut with my handy dremmel for velcro straps to hold it in position. Great success. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted February 13, 2016 Author Share Posted February 13, 2016 Have now made up the front battery and receiver tray with good pole switch from T9 and FR Sky Receiver - £21 against £60 for a Futaba version. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted February 13, 2016 Author Share Posted February 13, 2016 The front tray attaches to the rear with T Nuts and 4mm bolts. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted February 13, 2016 Author Share Posted February 13, 2016 I decided to try magnets to hold the wings onto the fuselage. I bought some 10mm Neomodium magnets which are really powerful, however getting them the right way round was difficult as the north and south poles aren't marked. I marked the position using the same carbon pencil rubbing method I used for the wing tubes. It worked To bore the holes for the magnets I used a rough dremmel permagrit wheel, which I had bought but not used before. I knew it would come in handy one day. Quote Link to comment Share on other sites More sharing options...
Andy Meade Posted February 15, 2016 Share Posted February 15, 2016 All looking great Pete - this is one I will definitely be building. They are such an iconic shape. One small note though - the antennae should really be at 90 degrees to each other. I've never had a range problem with my FRSky gear, but it is best practice - especially with all that carbon in there Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted February 17, 2016 Author Share Posted February 17, 2016 I agree Andy, but I can't work out how to put those aerial wires at say 75 degrees to each other and still attach them to the tray? I want to avoid ears out the top of the fuselage because it will be impractical if I am to slide it in and out, though I do know what you mean about carbon. I have intentionally not put any carbon over the area above the leads. Well tonight made up the elevator push rod out of a 6mm carbon tube with a 3mm insert to hold the pushrods. Nice and light and stiff but any better than 1/4 square balsa? I am not so sure. I used a bicycle spoke at one end, and wrapped it with carbon tow and some cryano. At the other end I used 2mm stainless steel studding which I found on Ebay - bought 5 metres which will last till I shuffle off this mortal coil. Much stronger as it will take the elevator end. I also cut a servo horn out of circuit board - was going to use some scrap veneer coated with carbon cloth cut out of the wing servo holes but much too flimsy. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted February 20, 2016 Author Share Posted February 20, 2016 Have attached the male multiplex plugs to the fuselage sides and filled round the back with epoxy and silica powder. Nearly there now. Need to do the wings and insert the female plug with some epoxy and microballoons. I will cover the surfaces with masking tape to stop it sticking. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted February 20, 2016 Author Share Posted February 20, 2016 Have started to cover with the lookalike carbon finish Oracover - expensive at £30 per roll but worth every penny. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted February 22, 2016 Author Share Posted February 22, 2016 Have attached the printed circuit board horn to the elevator in readiness using 5 minute epoxy (meant to use 20 minute but mixed the wrong one by mistake!) with some Xilica Powder which is light and strengthens the bond of epoxy but is much better than microballoons which is only for filler as it doesn't help the glue bond. Quote Link to comment Share on other sites More sharing options...
Mark Kettle 1 Posted February 22, 2016 Share Posted February 22, 2016 That Oracover looks brill Peter. Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted February 26, 2016 Author Share Posted February 26, 2016 Thanks, Mark, yes indeed it does. Oracover is so much better than Solarfilm because it can be removed and replaced without ripping the colour from the backing if you get it wrong. It is also thicker so it doesn't crease as easily. It looks just like Carbon as well. Will be trimming the ends of the wings and tailplane with fluorescent orange, yellow and green. Should look pretty. Anyway, I had to devise a way of keeping the canopy on. With mouldies a ridge is incorporated into the mould but not possible with lost foam, so I have to fibreglass a strip onto the inside of the canopy then dremmel it off when dry. It is time consuming because one has to do each side, and the top separately, then let them dry. Otherwise gravity would pull the fibreglass away from the adhered surface. Fibreglass strips wetted out. This shows one side after it has set and been dremmelled Other side held in position with Duck Tape until it is dry. Edited By Peter Garsden on 26/02/2016 09:31:32 Quote Link to comment Share on other sites More sharing options...
Peter Garsden Posted February 27, 2016 Author Share Posted February 27, 2016 The canopy supports have come out brilliantly. All that remains now is to finish off the Black Carbon lookalike Oracover on the fuselage, trim everywhere in fluourescent orange, yellow, and green - should look brilliant, servos in the wings, balance, then test fly - that is the scarey bit! Have put in an order for some JARTXL decals in white from Tim at Model Markings - highly recommended by the way - www.modelmarkings.com It is worth paying a small fee as against doing your own. I just can't get my inkjet printer to do white printing anyway, and I don't have a vinyl cutter. Quote Link to comment Share on other sites More sharing options...
Chris Barlow Posted February 27, 2016 Share Posted February 27, 2016 The carbon covering looks excellent Peter and orange tips will set it off perfect. Won't be long now. Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted February 27, 2016 Share Posted February 27, 2016 Pete....great job mate. On the subject of your aerial orientation - Andy is correct of course - they should be at right angles to one another. Yes the tray is narrow, but remember only the last 25mm or so is the "active" part of the antennae, the rest is just a miniature coax cable and it doesnt matter how that is configured. Plenty of room there to turn the end of one lead. Incidentally - putting on the pedant hat for a moment, its a toggle switch - the pole bit usually refers to the number of "poles" that are switched. Single Pole would interrupt just a single power lead - normally the live wire, whereas a double pole interrupts both leads. Variations include things like SPST ( Single Pole Single Throw ) and DPCO (Double Pole Changeover) etc etc. Many folks suggest that the more normally found slide switch is better for our applications, as the sliding motion of the carriage helps to "wipe" the contacts and self clean as it were. Personally, I've used a toggle style switch many times, and never had an issue - your mileage may vary. Edited By Tim Mackey on 27/02/2016 10:22:36 Quote Link to comment Share on other sites More sharing options...
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