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Lou Andrews Aeromaster Too, from AAMCO kit, built for electric ...

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    #16
    Here's the tailplane, mostly pinned up...

    ]

    ... and now all glued, ready to be shaped up. The hinge positions are marked out while it's still one piece



    To the right are the original pieces supplied in the kit. I've weighed both, and there's a 30 gr difference (26 built up, 56 original, without the tips...). A difference worth having..? I don't know, but it's as much fun building mine as gluing up the other planks. I'll try to remember to join the elevators before separation, too.
    Next up is the tailfin and rudder. I'll probably innovate there, too, as I like to be able to slot the fin into the tailplane, so I think I'll extend the fin further down.

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      #17
      Details, today, so not so spectacular. The elevators are still attached to the tailplane, and before separation, they must be linked. I've not used the supplied piece, as it no longer corresponds to the way I've built it, so I made my own, bending piano wire to the shape I wanted. This is a job for epoxy (I really don't like the stuff; horrible, messy gunk...); I milled a shallow channel into the balsa, and filled it with epoxy. I cleaner the joiner thoroughly, then pressed it into the glue , then poured more epoxy over. I say 'poured'; it's drop by drop, with a toothpick, trying to ensure a union between that in the trough and the layer I'm applying. The original squarish piano wire piece may be seen, for comparison ...



      It'll take a day or so to really go off, so on with other menial tasks. I started to cut out a 'floor' for the fuselage in balsa, then changed my mind and used 1.5 mm ply instead. It has been 'Swiss-cheesed' to allow the use of nylon ties or Velcro bands, and will provide some airflow, too...



      A bit difficult to make out in the photos, but here's a 'dry fit' in place ...





      OK; time to start on the tailfin and rudder. Here, too, I'm not using the kit parts, but will build in similar fashion to the tailplane. Here's the first pinning up...



      The original slabs are seen below, for contrast. I've allowed for a deeper bottom rail for the fin, as I plan to cut a slot into the tailplane and slot the fin through that, with a supporting 5 x 5 piece each side, inside the fuselage, under the tailplane. I think that this will be a more solid and stable way of attaching the fin, as long as it is assured to be perpendicular and aligned fore and aft

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        #18
        Here's the tailfin, unpinned, yet to be sanded down and shaped...



        The original pieces may be seen just above; they weigh 36 gr altogether; my built-up fin weighs half of that. Will it make a difference..? We'll see at the final weigh-in, but I don't think it'll make the 'plane fly any worse..!
        Of course, I just can't resist trying out the new pieces in their native environment...



        Just perched there for the photo, naturally, but it's encouraging to see it looking more and more like a 'plane..!
        More details yet to come, but I'll start preparing for the wings shortly. I've been looking at building the servos into the wing, one each side; I'll have to check that the wing thickness permits this with the servos I have. I've never done a bell-crank system, and would prefer, if possible, the more simple, direct, linkage of separate aileron servos. More on that later, though; I think I'll build the upper wing first. A bit of a tidy-up and I'll get stuck in...

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          #19
          I've been putting this off for the last day or so, under guise of 'preparation', though, to be fair, getting stuff ready is required, I'm not used to this sequence of gluing up the uppermost spars first. I've always laid down the lower spar first, then glued the ribs to that. Here, it's the reverse: the lower spars are only in place as a guide; the upper spars get glued up first. I don't know why it's done that way, but there's not much point in delaying any longer, so...
          I've pinned the supporting 1/4" spacers that will keep the semi-symmetrical ribs at the correct angle. I've basically only done flat-bottomed wings up until now, so this is new to me, and frankly a wee bit scary. ...



          The ribs have been carefully extracted from their die-cut sheets, after identification (not that easy; I had to do it by counting the number of each required...). I make sure that they're positioned the right way up, too, as they are not perfectly symmetrical. Here they are, all lined up...



          Now the scary stuff starts, for real. I pondered long and hard, trying to come up with e method or jig for cutting these long scarf joints, and ended up pinned the two pieces together, then carefully sawing through the two of 'em...



          There are surely better ways, but it's the best I could come up with, and the results are reasonable. At least I've not gone and spoilt a critical piece (yet..!).

          Here's the whole upper wing, then, all ready for the irreversible step of gluing it up...







          Up until now, these are just 'dry runs' and check fittings. Now I'll have to mount the stairs and start actually gluing stuff together. That's the part I've been avoiding, for fear of having missed something, or misunderstood the directions. There's no getting away from it, though; I'll just have to get started. I'll probably not get all the ribs done this evening, but at least I'll get 'em going. Back tomorrow, then...

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            #20
            Here go the first batch of spars; these are the top ones for the left upper wing ...



            The right wing followed in similar fashion (I wasn't comfortable doing both wings in one sitting...). Now for another delicate part: joining the wings with the scarf-jointed middle pieces. The first one goes in whilst everything is still pegged up ...



            ... with The Littl'un's Lego blocks helping to keep things square. Once set, the assembly was unpinned, and rocked backwards enough to have the rear spar lie flat on the table, and the middle section was then glued in. After a suitable delay, the whole structure was turned over and the lower spars glued in, then the lower centre pieces ...



            Next up will be the oddly-names centre section 'trailing edge cap', after which I'll have enough confidence in the rigidity of it all to do the leading edges. Frightening stuff; left to my own devices, I'm not sure I'd have done things in this sequence. I'm trusting that there's sound reasons for it all; at least it obliges me to check and double-check for flatness at every step. It's interesting, and quite satisfying, but creates nervous tension, so I can only do small steps at a time.
            While these parts are drying, I can deal with a detail or two on the fuselage, such as the cockpit surround. As I've plumped for a removable hatch, and decided to film this, rather than skin it with sheet, I've used only a small portion of the supplied cowling. I first glued the lower edge to the fuselage flanks, then, when dry, glued up the curved sheet, holding it in place with elastic bands and a clamp...



            No more this evening; tomorrow one last spar section, then the leading edge. I'm still thinking about how to hold the LE in place whilst the glue sets. I would normally have elastic bands fore and aft, but there's no TE as yet, and I don't want to manipulate the wing too much in this state. I may try to perch the wing on its nose, or simply chock it up. Hmm... more challenges ahead, then.

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              #21
              I think it's easier to fit the trailing edges now, as the wing can be rocked flat towards the rear. Here, then, is the left wing TE ...



              ... with the ubiquitous hammer helping keep the piece butted up to the ribs. The right panel gets the same treatment in its turn.
              Now for the centre section ribs. Some very slight adjustment is needed, as they are fitted from the front, and 'twisted' into place. After a dry run, to be sure there'll be no snags, they're glued up, and maintained square with the Lego bricks ...



              Tomorrow, then, t'will be the fitting of the leading edge. I've not tried all of my thoughts on how to do this yet, but, for the moment, the hottest contender is the 'standing on its nose' idea. One panel at a time; supported, of course in a vertical position, the other panel will have to be supported too, 'in the air', because of the sweep-back. I'll have to check on the best way of fitting the LE centre section as well; either glued first to the centre ribs, or inserted after the LE's are in place, between these and the rib noses. More fun in store for tomorrow, then.
              Goodnight, all...

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                #22
                Hi Dad! I'd say your doing a great job with those "funny" 'foils! slow and steady iz my "rule of the dy too!

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                  #23
                  I'd forgotten a set of ribs for the centre section, but stumbled across them just in time, and so in they went ...



                  They're important, as they take the strain of the upper wing attachment to the cabane. It wouldn't do to fly without 'em..!
                  No harm done, then, so we can crack on with the leading edge. The benefits of sleeping on a problem is that, often enough, the solution becomes clear. It's the case with my thoughts on how to fix the LE to the wing. It seemed evident enough, this morning, that, instread of setting the wing on its nose, I could far better set the LE on the wing's nose, so that's what I've done. The wing is supported upright, vertical, and the centre part of the LE is the first to be stuck on...



                  ... followed, after allowing the glue to dry, of course, by the two outer parts of the LE...





                  The afternoon seems suitable, and I had to wait for that centre piece to be ready, so I took my Prima, 3-axis trainer, to the club flying field for its 'maiden' flight. Each time previously, there has been a set-back, with the motor not running or a duff ESC. This time, all went well (better, even, than expected...). Full report and video in the Prima build log...



                  Now that the LE is glued on, I have to wait again, of course, so it's cauliflower cheese time. After dinner, I'll see about finishing off the trailing edge details, and probably start on the tips. Back later, then...
                  Last edited by Dad3353; 09-08-2018, 09:07 PM.

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                    #24
                    The little details are often the most fiddly; here's the cut-out surrounds being clamped up...



                    I read the instructions yet again, where I learned that the sheeting comes first, before the tips. No point putting it off, then, so here we go. Not much to see, of course, as it's under the press (Oh..! A pun..!). I can't do the whole width at once, so I start with one underside trailing edge ...



                    ... then the other ...



                    ... which went better than expected, thanks, to a great extent, to the smart idea of the folks who kitted this to design the sheeted parts to be exactly the length and width of the supplied sheets, so almost no cutting to do; just trimming each end because of the wing sweep. Result...



                    I had intended to continue with the underside leading edge, but, in my manipulations for sanding and checking, I inadvertently prepared and glued up the upper LE, where the curve is more pronounced. Never mind; I've started, so I'll finish. Glued up in two operations; firstly the spar (relatively flat...), so I could do the whole width in one...



                    ... then, after using a brush and thinned PVA to get glue onto the structure under the sheet, the LE itself. A different clamping technique is required for each circumstance; here, it's a bit delicate, as the curve of the LE is not the best surface for the spring clips. They're carefully placed, trying to avoid knocking any of those already in place ...



                    One side at a time, of course ...



                    ... but, again, pleased with the outcome ...



                    Now for the upper TE, where, once again, a new method for weighing down is needed. Even the lump hammer is insufficient for such a surface, so I improvise again ...





                    ... and finally finish off with the lower LE, with another array of spring clips...



                    That's the panels sheeted, then...





                    ... still flat and warp-free. It'll be the turn of the tips next (at last..!), then the centre sheeting. Enough for today, though; more tomorrow...

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                      #25
                      I've trimmed the entire wing, by whittling away the excess sheeting at the LE centre, then rough-sanding all around the edges. I've not yet formed the aerofoil rounding of the LE; that'll come later, when I get closer to covering. I've been thinking about these tips, and have come to the conclusion that, although they may well be strong enough once finished, there's not much to hold 'em in place at first. I've therefore decided to give them some support, by gluing a piece of triangular stock to the outer rib, parallel to the tip sheet, to which the tip will be glued...



                      A second tri-stock will then be glued on, clamping the tip in a 'sandwich'. I'll be much more comfortable for then fitting the remaining spar extensions. Maybe overkill, maybe a Good Idea, I don't know, but it's done, so there..!





                      Whilst these details are setting, I have time to ponder over another task I'd almost overlooked: the shear webbing. This afternoon, probably, or this evening...
                      Last edited by Dad3353; 09-14-2018, 03:08 PM.

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                        #26
                        Again, done in stages; many clamps needed...



                        ... but turn out to be not as 'painful' as I'd feared...



                        The centre section, too, with a different clamping configuration...



                        Next up will be the same again for the trailing edge webbing, then I'll finish off the tips...

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                          #27
                          Rib capping; no great surprises...



                          ... then sheeting the mid-section...



                          Yes, I know that you can't see much; that's because it's all under the magazines and, by popular request, the lump hammer. Here's the result...



                          Nearing completion, but still the tips to sheet. Once again, clamps, clamps and more clamps...





                          With all the sheeting, I 'feather' the joins whenever they meet, like a scarf joint. This gives a wider glue joint, and reduces the chances of gaps between sheets. The tip sheets were more heavily feathered still around the curves, so as to marry with the main, horizontal, tip sheet.
                          Only the top side for now, the underside tomorrow, when this gluing is fully set. Enough, I think, for today, night-night, all...

                          Edit : Not sure if it shows up very much, but here's the feathering of the underside tips, being glued up as I type...

                          Last edited by Dad3353; 09-17-2018, 11:27 AM.

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                            #28
                            That's it for this wing, all finished and rough-sanded...





                            Still the LE and TE to trim to final shape; I'll do that when I have both wings ready, and do 'em together.
                            I'm not convinced that this method for doing wing-tips is the best; I found it to be the least inspiring of the whole build so far, and not at all easy to get a decent result (always assuming that that's what I've got right now..! ). There's still time to think about it, but I may have a go at doing solid balsa tips for the lower wing. Not 'easy' either, but maybe more satisfying that these fiddly ones.
                            Having rough-sanded the whole wing, I now realise why so many folks use Titebond, rather than white PVA wood glue, for their 'planes. I try, always, to wipe away any excess glue as and when it occurs, bu, when sanding down these tips, I have to encroach on the dried glued joints, and encounter those rubbery balls that clog up the sandpaper and won't go away. They don't spoil the finish too much, especially as the 'plane will be covered, but there is a lot of time wasted on 'em, and they're a pain in the wotsit that I could do without. I may invest in a bottle of the Good Stuff, for gluing bits that may need sanding afrewards. I'm very happy with my PVA for general sticking purposes, but it would be better still to have the option.

                            Next task will be to find a suitable spot to keep this wing whilst building the other. Somewhere out of the way, flat and level. I've a fair few guitar cases; I'll see if one could be put to this use. Hmm... Meanwhile, I'll start preparations for the lower wing, with another novelty, for me... Ailerons..!

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                              #29
                              Not even the bass case is long enough to swallow the wing, so it's perched on my piano for the duration. I'll probably find a film to cover it over, although it shouldn't be too long before it has a stable-mate. I have a flight case for the piano, but it's a beggar to shift (weighs as much as the piano..!), so that'll stay propped up in the other corner.



                              Once again, then, identification of all these ribs. A bit late, now, to suggest, but it would have been helpful to have a 'plan' of the die-cut sheets, indicating which part is which. I have inspected them pretty thoroughly, and just as well, as there are numerous small pieces tucked away in the otherwise wasted spaces between the ribs. I've found, for instance, the pieces for the surround of the upper wing cut-outs, but too late, as I already made my own from scrap, ignorant of the presence of these parts. Here's how I've 'guessed' that the ribs should be placed ...



                              ...judging from the little clues, such as the marks for the aileron cut, or the holes for the servo control rods. There's one 'spare' rib, which I'll use as a template for a couple of rib doublers where I'll be installing wing servos; the control rod holes will become passage for the servo wires.
                              Still not comfortable with this method of gluing the top spars in first, but I'll follow the plan slavishly, as it worked out well enough for the first wing, despite my reticence. I've yet to receive my Titebond (ordered only yesterday, so..!), but my PVA will do fine here, as there'll be little or nothing to sand afterwards, and it is Exceedingly Good Glue, just the same.
                              The washing is out on the line, the dishes are washed up, too; I've even cleaned the cooker, so a whole afternoon for cracking on, with this, and probably the Condor, too. Lunch first, though; it's a question of priorities.

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                                #30
                                The Lego comes out again, with the elastic band clamps (very useful indeed; I'll get some more, I think...) and the top spar is shaped, then glued in ...



                                I don't think it's very visible, but there are holes pierced through the inner ribs, for the future passage of servo wires, as I'll be mounting those in the wing, instead of and in the place of the bell-cranks for a central servo. To make the holes, I clamped those ribs between the new, ply, rib doublers, and drilled a hole through the stack with an ordinary wood bit, but well undersized. I then used a 'bullet'-shaped grinding stone for my mini-drill to open up to 10mm. A bit of patience gave a pretty good result, with no tearing around the holes. I know there are other methods, but this worked well enough.
                                Tomorrow, when the glue has set, the rear spar goes in, and I'll do the same for the other wing half. Incidentally, the ribs fit so well onto the spar that they reproduce the sweep angle, so I have to pin the Lego bricks to keep 'em straight fore and aft, as per the plan. Another episode tomorrow, then...

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