Fly_Boy_Rez Posted January 31, 2014 Share Posted January 31, 2014 I’ll come right out and confess it’s been a few years since I actually built a traditional balsa and ply aircraft. With that in mind I’ve been ardently reading the build blogs by RedBaron and John Hayward and tapping up my good friend Phil Cooke on best practices, hints and tips etc and have embarked on this build a little early. The laser cut wood pack, plan and canopy were ordered from Traplet and arrived very short order so top marks to Traplet there. I then inventorised what wood stock I had left over from the last build and set about ordering the rest from SLEC using RedBaron’s blog as a guide. Sadly I think I over did it so I’m possibly in a position to build three JPs! The plan was studied, the build article read, the plan studied again and then off to B&Q to buy a sheet of plasterboard as a nice cheap but importantly flat surface that’s easy to pin to. I should at this stage mention this will be a build log simply cataloguing my build... I have no doubt you will learn more from the more experienced builders! The first job was to cut out the wing section of the plan and to tape that down onto the building board securely. The lower wing skin was then glued together as recommended by taping the two halves along the mating edge, gluing and pinning down flat with some weight applied, but where to get the weight from? Well hard drives of course! I mean, who doesn’t have twelve old hard drives sitting around gathering dust right? While that dried I set about correcting the previously identified error on former F1, adding the necessary slots to the side cheeks. More to follow... Rez Quote Link to comment Share on other sites More sharing options...
Fly_Boy_Rez Posted January 31, 2014 Author Share Posted January 31, 2014 Time now to move back onto the wing. The glued panels were sanded and pinned to the board prior to transferring the shape and location markings from the plan. If I'm going to give you one tip in this blog it will be to "Check your dimensions, then check them again". If only I'd followed this mantra! A slave leading edge was located on the lower wing sheet and the ribs were glued into place one by one, ensuring all the ribs were perpendicular with the lower wing sheet with these little gadgets. With only 4 of these little 'doohickies' it took a few days for the ribs to all be glued in but we got there eventually. The wing has also had all the webbing fitted between the ribs. Ribs R1 from both sides are loose in this shot. Now time to move onto the nose section. In the background of the above image you can make out the balsa box around which the nose section formers are located. F3 has had to be made from scratch as the ply sheet it came on was warped like a pringle and so F3 was near useless. Luckily it's a pretty simple shape. The nose section is now in a good state, ready to start accepting the fuselage sides. Interesting observation about the Cyparis used for the stiffener F13... when sanded it smells just like steamed wallpaper! More to follow... Rez Edited By Fly_Boy_Rez on 31/01/2014 23:38:51 Quote Link to comment Share on other sites More sharing options...
RedBaron Posted January 31, 2014 Share Posted January 31, 2014 Hi Rez, Looking good! I would like to apologise if I caused you to over order. Originally in my NoteBook I listed what I ordered (to stock up). I thought I had mentioned that. As I have actually used wood I have gradually changed the numbers to reflect what is really required. Instead of building 3 JPs why not one as per plan and then a twice size jobby? Best wishes RedBaron Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted February 1, 2014 Share Posted February 1, 2014 Nice one Rez, looks like you're making some good progress with the build - keep it up! Quote Link to comment Share on other sites More sharing options...
Tony F Posted February 1, 2014 Share Posted February 1, 2014 Also watching this with interest, Looks great already...! Always wondered where hard drives went to retire..... Tony Quote Link to comment Share on other sites More sharing options...
Matt Jones Posted February 1, 2014 Share Posted February 1, 2014 Looking good Rez but I have to ask, how many hard drives!?!?!? Quote Link to comment Share on other sites More sharing options...
Fly_Boy_Rez Posted February 1, 2014 Author Share Posted February 1, 2014 RedBaron, No apologies necessary... it never hurts to have spare wood and I'm sure I'll use it for the next project! Regarding the hard drives... well that's from years of PC repairs and looking back on it now it's clear the one component most likely to go south appears to be the hard drive! Remember, make regular backups people! Back to the wing again, these next few shots are describing the incremental additions to the wings... First up the trailing edge strip which will get sanded to a wedge and the strip at the trailing edge of the aileron. This time it seemed appropriate to weight it all down with some big D cells. At this stage I thought it might be nice to clamp the two halves together and see how we're getting on Time to move onto the slave leading edge strip And finally to trim the lower skin to shape and fit the Rib reinforcement. More to follow... Rez Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted February 1, 2014 Share Posted February 1, 2014 Nice looking build Rez. Just a quick question - is this a PSS model? Quote Link to comment Share on other sites More sharing options...
Tony Bennett Posted February 1, 2014 Share Posted February 1, 2014 that is very neat building rez. Quote Link to comment Share on other sites More sharing options...
Fly_Boy_Rez Posted February 1, 2014 Author Share Posted February 1, 2014 Thanks for the kind words chaps! This is indeed a PSS aircraft, Andy Blackburn's design and hopefully one of many as part of the PSSA mass build. Should be quite a sight seeing lots of JPs flying together at the Great Orme in June! Quote Link to comment Share on other sites More sharing options...
Fly_Boy_Rez Posted February 2, 2014 Author Share Posted February 2, 2014 So, onto the wingtips. As per the plan they are a laminate construction with the thinnest sheet of ply I've ever seen sandwiched with balsa top and bottom. While that sets I moved on to building up the laminates for the tip tanks. Luckily I'd ordered after the correction to the tanks layers had been made so I got all three aerofoil shaped cutouts. That said I think I've ended up gluing the wrong pieces in as well... oh well, more shaping and sanding at the end! Seeing all the shaping that would be required I sent off for a 'Davids' razor plane... top bit of kit this but folks... watch those fingers! This thing cares not whether it is slicing wood or flesh! After much whitling and sanding I have one shaped tank... I'll confess it's not desperatley round yet, so a bit more fettling will be required no doubt! More to follow... Rez Quote Link to comment Share on other sites More sharing options...
Fly_Boy_Rez Posted February 4, 2014 Author Share Posted February 4, 2014 Started working on the fuselage sides, gluing down the various triangular sections and doublers: Whilst waiting for the sides to dry I set about shaping one of the wing tips to fit the tip tank... got a nice snug fit there: And so to the process of assembling the sides onto the nose assembly: Not sure if my build/cut skills have let me down or there's something up with the triangular sections but to get the contacting faces of the sides and the formers F2/3/4 to touch for gluing and not end up with a concave and distorted nose took many trial fits to find the areas of interference and then dress them away. A total of six clamps were used in the assembly! I must confess to having made an error at this point! I failed to put slave wood between the clamps and the model and so I suspect when All's said and done I'll be filling and sanding some nasty looking dents! More soon... Rez Quote Link to comment Share on other sites More sharing options...
Fly_Boy_Rez Posted February 16, 2014 Author Share Posted February 16, 2014 So, having given the glued fuselage sides plenty of time to dry attention turns to building up the nose. First up I started blocking in the gap between F1 and F2 Next, I moved to the blocks ahead of F1. To ensure I got the bixed section extension as defined in the plan I built this to block up against. While this little lot dries, I think it may be time to return our attention to the wings... Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted February 17, 2014 Share Posted February 17, 2014 Looking good Rez - like the nose guides in plan and profile, that's a good idea will aid sanding! Quote Link to comment Share on other sites More sharing options...
Andy Blackburn Posted February 17, 2014 Share Posted February 17, 2014 rez wrote: > ... I'll be filling and sanding some nasty looking dents! In case it's been so long since you built anything that you've forgotten about this one, but I commend to you the use of a hot (very hot) covering iron applied to a well-dampened dent... Quote Link to comment Share on other sites More sharing options...
Fly_Boy_Rez Posted February 25, 2014 Author Share Posted February 25, 2014 Thanks Andy, never knew that...! So, let's continue this build story...Ahh yes, the aileron torque rod story. Well, I had some rods which I thought would be man enough for the job, so to test them I first knocked up a test rig And when that seemed to work I set about installing the torque rods in the wing. However having installed the torque rod I quickly setup a link to the servo and holding the aileron end discovered that the rod was indeed too flexible. At this point Matt Jones came to the rescue with a set of pre-formed and sleeved aileron torque rods. These were secured to the ribs with thin ply and CA. More to follow... Quote Link to comment Share on other sites More sharing options...
Fly_Boy_Rez Posted February 25, 2014 Author Share Posted February 25, 2014 Time now to join the wings. I'd decided to pre-join the wing halves ahead of top skinning. I wanted to have more control over the position of the joiner strip than cutting a slot in the newly installed top skin and besides this approach felt a little too much like gynaecology to me! Ribs R1-3 were pre-slotted ready to accept the joiner and the wing halves wre glued together. Once that was dry I set about inserting the joiner, and adding small triangular stoke to give improved structural joints Once all this was set I installed a secondary box structure into the wing. The aim of this structure is to locate and guide the servo lead out of the wing. The new internal walls were sanded to be flush with the ribs and then it's time to move onto application of the top skin of the wing. To ensure I got this right, I created a paper template which was trimmed and modified until it was giving all the right slots. First wing skin was applied with zero fuss... More to follow soon... Rez Quote Link to comment Share on other sites More sharing options...
Fly_Boy_Rez Posted February 26, 2014 Author Share Posted February 26, 2014 First wing top skin was soon followed by the second... Next up the strengthening for the bolt hole and also some very thin ply around the aileron rod's exit through the wing skin just to make it a little more resilient to my fat hands! Next some more of the light ply to the end of the aileron cut out, again to make it a little more resilient More to follow... Rez Quote Link to comment Share on other sites More sharing options...
Phil Cooke Posted February 27, 2014 Share Posted February 27, 2014 Some good progress Rez! Is your strengthening for the wing bolt hole balsa or ply? if its balsa on top, do make sure you use a ply on the bottom (will sit under the belly pan) as it looks like you didn't 'pack out' the wing inside in this area before fitting the top skin? Sure it will be fine with a 1/16th ply on the bottom side, esp if you use the little wing bandage. Quote Link to comment Share on other sites More sharing options...
Andy Blackburn Posted February 28, 2014 Share Posted February 28, 2014 I'd advise ply top and bottom, TBH - otherwise, what tends to happen if you stuff it in hard enough to break the front wing dowel is that the wing - being thin where the wing bolt is attached - dissipates the energy by bending downwards rather than breaking the bolt, and one then has additional repair work to do. Quote Link to comment Share on other sites More sharing options...
Fly_Boy_Rez Posted March 1, 2014 Author Share Posted March 1, 2014 Thanks for the discussion chaps! I've fitted the ply to both top and bottom. So, onwards with the wing. Oversized material for the LE is glued on: and sanded to profile Next up the wingtips are added to the wing Next a set of ailerons More to follow! Rez Edited By Fly_Boy_Rez on 01/03/2014 23:18:20 Quote Link to comment Share on other sites More sharing options...
Fly_Boy_Rez Posted March 2, 2014 Author Share Posted March 2, 2014 More on the wing then I'd initially made a left aileron by taking a basic plank, cutting it to shape and then sanding it down to an aileron like profile. Looked lovely too, but when slotted for hinges and the torque rod and then fitted I realised it didn't fit! The problem was that the aileron made in isolation as it was knew nothing of the wingtip washout so the trailing edges don't lne up! I therefore started again using aileron stock which at the inboard end isn't deep enough for the slot. A strip of 1/4" stock was therefore glued to the leading edge and when dry the shaping began. The outbaord edge is now too long and too deep for the trailing edge when cut back. The solution was to finish it off as an oversized aileron, fit it, secure it to the wing at the inboard end with a spring clamp, then trace the shape of the wingtip onto the end of the aileron and use this as a trimming / sanding guide. Sadly I forgot to take pictures of this stage so I'm afraid you'll have to use you imaginations! The wing is now largely done... That said I still need to drill for the wing bolt, make servo rods and face the underside so maybe I'm not there yet! More to follow! Quote Link to comment Share on other sites More sharing options...
Fly_Boy_Rez Posted March 2, 2014 Author Share Posted March 2, 2014 I've now turned my attention back to the fuselage. Following Phil's lead I've elected to trim the cocpit area out whilst I still have square sides. Carefully marked out and cut out, and then faced off with 1/16 balsa as per plan. A little additional material was put back in to replace the triangular stock than fell off and also to provide a support on former F4. For elevator control I've elected to dispense with the snake and will be using an old skool balsa pushrod. To this end I marked out suitable snug holes for the pushrod to pass through formers F6 and F7. More to follow... Quote Link to comment Share on other sites More sharing options...
Fly_Boy_Rez Posted March 2, 2014 Author Share Posted March 2, 2014 Whilst doing all this I was also preparing the nut plate for the wing bolt. No pictures I'm afraid! It's been glued in and former F6 followed shortly thereafter, once again requiring the triangular stock to be locally dressed away to permit the former to fit properly against the fuselage sides. While waiting for this little lot to dry I set about preparing the elevator torque rods. Mirrored sets of rods were prepared, held closely together in a vice and a quick solder joint made to 'tack' them together. I then set about making the joint stronger by stripping the insulation off an electrical wire, wrapping the copper (untwisted) around the paired rods and flowing solder into the joint. The excess was trimmed off with my trusty Dremel and then I set about preparing it for the next stage which was to solder on in the same way a threaded end fitting. These are normally soldered onto the ends of steel rods, I chose a slightly different approach! The next section of copper strands were soldered into the end of the fitting, and then wrapped around the fitting and the torque rods and soldered up. The excess was again dressed off with the Dremel, the threads wirebrushed and a metal clevis fitted. The pushrod end will feature either a ball joint fitted to this or another homebrewed special akin to RedBaron's! More to follow... Quote Link to comment Share on other sites More sharing options...
Fly_Boy_Rez Posted March 6, 2014 Author Share Posted March 6, 2014 Looking back on my last few posts now I can see that I'm jumping around a bit... sorry about that but that's just how this Blog is ending up! Coming back to the front end of the elevator pushrod I decided I'd sort out the servo location whilst I still had access to the fuselage from top and bottom. Using some of the spare Cyparis I made a pair of braced bridges for the servo to sit on and moved them axially as far forward as I could whilst still allowing easy access to the battery / Rx box in the nose. The shot above is an interim position... it ended up further forward than this! Taking advantage of the lack of fuselage planking at this point I thought I'd have a go at offering up the wing... wow, I'd heard the wing leading edge dowel hole and the hole in former F4 didn't line up but I wasn't expecting it to be quite this far out! I'm not sure how I've manafed to geti ti all so horribly wrong?!?! Another reason for this check was to make sure I wasn't going to get a clash between the wing servos and the elevator servos. Thankfully we're all clear here! That's it for now... I've realised I've failed to order any dowel stock so I'd better get some in soon, and I need to have a think about how I've managed to get the wing dowel and hole locations so far out! Rez Quote Link to comment Share on other sites More sharing options...
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