Greg Minden Posted February 5, 2020 Share Posted February 5, 2020 Good work Peter. BTW , have you measured the wingspan yet on your "78" Vulcan? Quote Link to comment Share on other sites More sharing options...
PeterF Posted February 5, 2020 Share Posted February 5, 2020 Yes, it is about 78" at the moment, when I put the wing tips on it will be about 83". Not sure why it is called 78". Quote Link to comment Share on other sites More sharing options...
PeterF Posted February 10, 2020 Share Posted February 10, 2020 The second wing has now been completed to the same stage, sheeted both surfaces, servo mounting rails installed, wing tubes cut and checked. I have added another photo of the wing retention system before sheeting with the aluminium plate bolted into place on both sides of the wing joint. As noted previously, I have followed the photo instructions. The oddest job was gluing the wing frames to the fuselage and sheeting over everything, then cutting off the wing panels afterwards, first time I have ever done anything like this. From the photo below, the wing joint is between the second and third ribs, which are spaced a hacksaw blades width apart with some thin balsa sheet, ready for cutting after sheeting is complete. Ready to add the leading edges, wing tips and the control surfaces. Quote Link to comment Share on other sites More sharing options...
Greg Minden Posted February 10, 2020 Share Posted February 10, 2020 that's how to do it! Quote Link to comment Share on other sites More sharing options...
PeterF Posted February 23, 2020 Share Posted February 23, 2020 Leading edges, wing tips, inner elevators and outer elevons now all completed. The only bit that has given me some pause for thought was how to build the outer elevons with the reflex built into the outer half of these, none of the surfaces were flat to build them on the board in the normal way. I have tried to sand the trailing edge of th wing tip blocks to follow the reflex on the outer part of the elevons. Edited By PeterF on 23/02/2020 19:55:30 Quote Link to comment Share on other sites More sharing options...
PeterF Posted March 28, 2020 Share Posted March 28, 2020 I have added the inner sheeting in the inlet ducts. I have made this full lenth back to the former with the fan inlet to give a smoother flow area for the air going to the fans. The corner infills have also been added. I have fixed the rudder in position and added the spine along the top of the fuselage. That about finishes the majority of the build. Now to start sanding and filling in preparation for glassing, parcel arriving Monday from East Coast Fibreglass Supplies. That will keep me occupied for the next 2 weeks of lockdown (or more). Quote Link to comment Share on other sites More sharing options...
Greg Minden Posted March 28, 2020 Share Posted March 28, 2020 Looking good. I became worried that the flat bulkhead next to the fan intake would reduce efficiency and power so decided to fair in the inlets to the fan. Seemed like a good idea and my thrust measurements would agree Quote Link to comment Share on other sites More sharing options...
PeterF Posted March 28, 2020 Share Posted March 28, 2020 Posted by Greg Minden on 28/03/2020 21:38:41: Looking good. I became worried that the flat bulkhead next to the fan intake would reduce efficiency and power so decided to fair in the inlets to the fan. Seemed like a good idea and my thrust measurements would agree My view on this is that with a full lip on the fan inlet, it should not matter as this will feed the air smoothly into the fan and the inlet area is larger than the FSA so that air flow will only need to change direction and accelerate at the fan inlet. The proof will however come some time in the future as I will not be cutting the access hatches until I have glassed the fuselage. Quote Link to comment Share on other sites More sharing options...
Craig Carr Posted March 29, 2020 Share Posted March 29, 2020 Hi peter, your ducts look great, very neat. How did you make them, I found pre-making a balsa tube as shown on the plan then inserting nigh on impossible and gave up after a couple of attempts. In the end the only way I could do it was to carefully build the duct”in situ” Quote Link to comment Share on other sites More sharing options...
PeterF Posted March 29, 2020 Share Posted March 29, 2020 Craig, I did not take any in build pics of the ducts. I made up a single sheet of balsa larger than required but did not glue it into a tube. I soaked it and then formed a tube smaller than the intake with a loose overlap and inserted into the hole. Once in the hole I expanded it to fit, marked off the diagonal front of the intake and the point where the overlap came to. I then removed the sheet, cut back to the diagonal lines leaving some spare and cut back some the spare overlap, but not all of it. I then refitted the sheet to recheck the overlap position, removed it and made the final cut. I then glued it into a tube and inserted it for the final time, but to get it in it needed to be soaked again and one of the flat faces bent inwards to make the overall size smaller than the hole. Very fiddly. Quote Link to comment Share on other sites More sharing options...
Greg Minden Posted March 29, 2020 Share Posted March 29, 2020 I too had to do it like Craig said - in pieces. The other way just wouldn't work for me. That done - i kept looking at those flat "air dams" next to the fans and, well you know the rest. Probably uneeded. Quote Link to comment Share on other sites More sharing options...
PeterF Posted April 4, 2020 Share Posted April 4, 2020 Greg, In my professional life before retiring I was involved in the designed of high velocity fluid flow components and a rounded lip on the entrance to a duct is as good as a shallow cone in keeping flow disturbance to a minimum, both answers are equally as valid. Craig, Have you made any further progress on your build. I have started glassing and have completed the fuselage. This was the stage I was not looking forward to. I have only glassed a plane once and that was 15 years or more ago and it did not turn out very well, it needed a lot of sanding and a lot of high build primer and turned out overweight. It was a DC3, needless to say extra weight on a plane with heavily tapered wings was a bit of a nightmare. I watched the videos by Danny Fenton "Glassing my Way" and "Hawker Fury Mk1 fuselage glassing" and I have followed those methods using the foam brushes and peel ply. I wish I had seen this years ago because it has been a lot easier than my first attempt and has resulted in a good even lay down of the cloth with good adhesion and very few areas with excess resin. I used West Systems epoxy 105/206 and glass and peel ply from East Coast Fibreglass supplies. The only thing I have found is that the foam brushes start to break up after a while, perhaps I am too rough with them, having a pack of 20 means I have lots available to keep swapping as soon as any black bits appear on the glass cloth. I have used both resin addition methods, adding it to the surface first then placing the cloth down and placing the cloth on dry then adding the resin. I can not make my mind up which is the best yet, the end result appears to be identical. Fin and wing join reinforcement panels glassed with peel ply Upper fuselage completed ready for sanding The majority of the bottom of the fuselage glassed in one mammoth session. This was done in two halves with an overlap on the centre line First side of the peel ply being removed Underside of the fuselage completed ready for sanding Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted April 5, 2020 Share Posted April 5, 2020 Please remind me which fans you are using. I have just blown up the impeller on my Hawk while messing with it on the bench. A loose connector got sucked in! Ordered a new sort of similar one from HK and hope that it fits but it could be a long wait. Current one is 12 blade 10s. Quote Link to comment Share on other sites More sharing options...
Greg Minden Posted April 5, 2020 Share Posted April 5, 2020 Martin - I don't know who you were asking but i am using Jet Fan 90s with HET motors on 10s. (9 blade) Quote Link to comment Share on other sites More sharing options...
PeterF Posted April 5, 2020 Share Posted April 5, 2020 Martin, The fans are from Exreme RC in Australia with 90mm machined alloy shrouds fitted with Ejet Jetfan 90mm 9 blade rotors and HET 650-68-1600 motors. On 8S they should pull about 100A and give 4.5kg thrust. Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted April 5, 2020 Share Posted April 5, 2020 Thanks both. Quote Link to comment Share on other sites More sharing options...
patrick mcateer Posted April 12, 2020 Share Posted April 12, 2020 hello Peterf, ive tried to pm you for the file but its not letting me. i think your doing a brill job there and its help me loads as im building the same as vulcan as you. keep up the great work Quote Link to comment Share on other sites More sharing options...
PeterF Posted April 12, 2020 Share Posted April 12, 2020 Patrick, welcome and feel free to chip in. I have sent you a pm to see if you can reply to that. Last few days has seen me complete the glassing of the plane by doing the wings, again same method using peel ply as for the fuselage. I have also added a lot of little bits and pieces as I move toward putting the first coat of primer on. This includes the cockpit, where I have 3D printed a bit of a pastiche of the cockpit rather than an accurate scale cockpit, the whole plane after all is not an accurate scale model. To finish it off I have stuck on a print of the dashboard from a full scale Vulcan. I have painted the inside of the cockpit moulding matt black after putting some masks over the windows so the contents can be seen. When the plane is painted, the outside of the cockpit moulding will be painted, covering the matt black. I have glued on the 3D prints of the nose cone, tail cone and engine exhuats. I have reprinted these with thinner walls and less infill to save some weight, the exhaust nozzles have now been printed only 2 layers thick, i.e. 0.8mm. I have added the infill below the rudder, the ABS moudlings for the top rear of the jet pipes, the boards on the inboard sides of the intakes, the seperators in the inlet duct to mimic the feed into 2 turbines on the full scale, the one I have inserted have been rounded at the front and tapered at the back to minimise turbulence spilling into the fans. I have also made up the doors for the nose wheel well as I did not plank over this whilst sheeting the nose, so I did not have a section of skin to cut out for the doors. These have been duly glassed. Quote Link to comment Share on other sites More sharing options...
Greg Minden Posted April 12, 2020 Share Posted April 12, 2020 doing a fine job. Did you mention what you are using for power. I am running 10s on each side and i found that i needed to put the 6s packs fully aft and the 4 s packs fwd to balance. Mine turned out a bit nose heavy. That's with the receiver and one 6 cell rcvr battery aft and one 6 cell receiver battery and the gyro fwd. I think i've got about 40 ft of wiring in mine! Quote Link to comment Share on other sites More sharing options...
PeterF Posted April 12, 2020 Share Posted April 12, 2020 Greg, The fan details are a couple of posts up in answer to Martin's question, they are slightly more efficient than the Jetfan shrouds as they have a smaller motor housing, they will only take the 650 HET motors. I will power it with 4 packs of 4S 5000mAh. These are the Turnigy Heavy Duty packs and they weigh a bit more than equivalent capacity packs, in total 5lb 3oz ( 2.35kg), I already use them in an EDF pulling 105Amps without problems. The ESCs are YGE HV 120Amp units. I have some scope for moving the batteries fore and aft, all my radio gear will be at the back, but my alloy fan shrouds will be heavier than yours. Finding a plane with a forward CoG is a rarity. This is one reason I reprinted my 3D parts as the nose cone was quite heavy. Quote Link to comment Share on other sites More sharing options...
patrick mcateer Posted April 13, 2020 Share Posted April 13, 2020 good morning Peterf, I cant open the pm it keeps saying your profile is not made public. so I cant get the file. my email address is [email protected]">[email protected] if you could email them to me please. im going to make a start on the wings today. the power plant im thinking of using is the lander 90mm 12 blade 10s edf units. im waiting for (tony) from robotbird to get back to me with details. do you have a picture of how you paired (wired) both batterys to give you the 10s. im going to put the battery hatch on the top of the plane as it makes sense for access. keep up the great work Quote Link to comment Share on other sites More sharing options...
PeterF Posted April 13, 2020 Share Posted April 13, 2020 Patrick, I use XT90 connectors so I added two connectors to the ESCs to give 8S from 2 4S batteries in series. The +ve pin on one connector went to the ESC +ve, the -ve pin on the other connector to the ESC -ve and then a bridging wire (shown blue in this pick) between the unused +ve and -ve pins on the connectors. This is illustrated below, but this is only a dummy pic I created with a spare ESC, the Vulcan ESCs are currently boxed in the fuselage and I can not photograph them until I cut the battery hatch free. Quote Link to comment Share on other sites More sharing options...
patrick mcateer Posted April 13, 2020 Share Posted April 13, 2020 brill thanks Peter Quote Link to comment Share on other sites More sharing options...
Greg Minden Posted April 13, 2020 Share Posted April 13, 2020 Peter - the usual way to achieve multiple hookup is to use a "y" harness easily available from H King and many sources for less than $10. I will point out that my motors each draw close to 100A at full power on 10s so you might want to rethink your Turnigy 60. I am using Castle 120HV. Quote Link to comment Share on other sites More sharing options...
Greg Minden Posted April 13, 2020 Share Posted April 13, 2020 OOps - i see in your previous post that you are using 120A ESCs. Sorry for the confusion. But, easier hookup with the "Y" harness Quote Link to comment Share on other sites More sharing options...
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