Mike Chantler Posted July 13, 2024 Author Share Posted July 13, 2024 Did 2 coats of light filler tinned to double cream with a bit of talc but no water Went on quickly, was a bit worried about all the bits in the mix - but sanded away quickly, sprayed with deep fill primer and sanded to what I thought was a nice finish 🙂 This went much faster than a PSS I did before, think it was applying the glass early in the process as this gives plenty of warning of potentially wrecking the surface by sanding through to the foam. Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted July 13, 2024 Author Share Posted July 13, 2024 (edited) Had a bit of a disaster with the Montana Gold. Paint looks as if it dried before hitting the wing - result is a finish rough as 90 grit, and I'm not joking 😬 Didn't hep that I didn't have my reading specs on so didn't realise until I'd finnish - was just way over-confident given success on a previous model. Decided just to go with it as it's just a 'quick' slope model, hay ho ... 🙄 And a bit of a storey behind the wing bolts: used test part print of fus to align tap at correct angle, it's balsa so threads need toughened up with CA a 2,3 times, impatience got the better of me and I managed to retap before the hot CA had completely cured ... Wrecked tapped hole and tap 🙄 An insert nut saved the day, remembered to coat bolt with wax and epoxied inset in and it worked fine, phew! (and one side seems to be enough) Edited July 13, 2024 by Mike Chantler Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted July 13, 2024 Author Share Posted July 13, 2024 Made up some linkages, had to replace the 105HV servos with 125WVs, as one of the 105s failed (eek) Drinking straws for servo runs worked well as the normally awkward twisted wiring just pushed through 🙂 Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted July 13, 2024 Author Share Posted July 13, 2024 Soldered up cables and started putting it together 🙂 Quote Link to comment Share on other sites More sharing options...
PDB Posted July 13, 2024 Share Posted July 13, 2024 Interesting build 👍 Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted July 14, 2024 Author Share Posted July 14, 2024 Thank you for your interest 🙂 Programmed radio yesterday, so all I have to do is nose weight. Was going to do that today - but the Pentlands seem to be in the doldrums so will have to wait (hopefully) until next week. Interested to see how much heavier it will be than the version covered in laminating film. 1 Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted July 16, 2024 Author Share Posted July 16, 2024 Ready to go and with nose weight it's 1120g That's about 250g heavier than the laminating film version. That said, I normally fly the lam version with half ballast to give reasonable loops and rolls, so given that it's a lot cleaner it will be interesting to see how it flies 🙂 Hopefully we'll have wind on Sunday 🙂 1 1 Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted July 30, 2024 Author Share Posted July 30, 2024 (edited) Took it up the Sunday before last - and it was a bit like a bucking bronco, suspected CoG, had rough landing, broke front bolt and snapped rear fus. so could not experiment that day. Measured CoG when home, and some how or other it was 3mm further back than intended (duh 🤔 ) Thought I'd been pretty careful with setting it up as well 😮 Anyway, adjusted CG and up hill last Sunday and it seemed to fly very well, PW51 seems a lot more slippery, faster and tracks well. Well pleased 🙂 Somehow or other I managed to get the control horn holes too far forward (again, thought I'd been quite careful here!!) but I seem to have almost twice the amount of up as down!! Rolls are currently very non-axial, which I'm putting down to the tons of +ve differential, and I have a feeling that planks require a little -ve differential? Anyway - will get some programmable aileron and elevator differential added for next trip. Looking forward to getting that sorted and adding ballast 🙂 Edited July 30, 2024 by Mike Chantler 2 Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted April 30 Author Share Posted April 30 Aileron and elevator differential sorted behaviour - the PW51 needs a bit more speed than the MH45 laminated one, but it is definitely more slippery and holds big loops well. I usually take it when I recon the wind on the ridge at +15mph, I take the 800g laminated MH45 version when less. Had the PW51 up on Sunday in 30, gusting 40mph and it flew well, although i was a bit nervous of the landings. So a good combo that has kept me flying in most winds about every Sunday since the last post 🙂 Both are getting quite a bit of hanger rash. So I'm in the middle of making a foam-veneered PW51 replacement wing, which I am hoping will be more ding proof 🙂 Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted April 30 Author Share Posted April 30 Current thoughts are to print another PW51 fuselage without any mods, to add pretty conventional veneered foam wing: Not sure about best way to do front bolt fairing/mount thing or best materials for tips to make light but ding proof 🤔 Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted April 30 Author Share Posted April 30 A start: 1 Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted May 9 Author Share Posted May 9 (edited) Busy at work - so only had one day building. Bagging had worked ok but for some curl on the TE, and top skin slipping back a little at LE. Forgot carbon reinforcement over wing brace - grrr! Should be strong enough without 🙄 Started under/over servo housings. Miss-placed template for servo linkage channel slightly, as lined up on veneer rather than core - sand root square first next time to provide correct datum! Promised myself last time that I would 3D print servo boxes (making them both took a good afternoon+ I think). Designing took 1/2 day 🙂 Starting to square sand tips, LE and trimming extra 5mm off TE. Next time I should look at extending the TE as one veneer shifted and others did not glue as well at LEs as I would like. Getting there though 🙂 Edited May 9 by Mike Chantler 1 Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted May 10 Author Share Posted May 10 (edited) TE cut with side dremel + 1" L section alu guide -- worked really well 🙂 LE and tips sanded square -- 1m 180 grit sanding bar worked well 🙂 (thought it might be too rough) 3mm cedar (or similar?) LEs glued with foam sort-of contact adhesive (could not remember what I usually use for this! - think I have tried white glue (does it stick?), 5min epoxy (pain to sand), gorilla glue (messy as expands everywhere 😞 and this contact stuff which being a contact adhesive will not fill voids) - so fingers crossed! Noticed that right wing veneer lifting slightly at LE, but taking the chance that the 3mm LE will keep it all together 🤞🤞 Well taped!! Now the hard part - resisting temptation of removing the tape to see if the glue has stuck yet 😳 We'll see if my run of luck continues 🤞🤞🤞 Sunday weather looks good for a fly of existing versions with the Pentlands club 😊 Edited May 10 by Mike Chantler Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted May 12 Author Share Posted May 12 (edited) Just started to print a couple of fuselage sections when I found i had already printed them : senior moment or what 🤒 Cut out recesses in rear of wings for fuselage and shaped LEs enough to test fit: Phew - looks fine 🙂 (setting the right kerf on the hotwire program can be a bit hit and miss) Added 3mm liteply sub-tips (with the contact adhesive again as this worked well on the LE strips). Hoping this will stop LE being staved in at the tips on fast landings, and protect the ends of the elevons a bit. Cut and laminated some balsa for the tips - first bit of balsa on the plane 😮 Last time I remember I should of added tip gussets - hmmm... Edited May 12 by Mike Chantler Quote Link to comment Share on other sites More sharing options...
Konrad Posted May 12 Share Posted May 12 Senior moment, not just you. I’ve been staring at that photo for a long time and seeing an EDF bifurcated inlet and exhaust. It took a second or third look and seeing the heading soaring to realize it is a fuselage with clearance for a wing. Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted May 13 Author Share Posted May 13 12 hours ago, Konrad said: I’ve been staring at that photo for a long time and seeing an EDF bifurcated inlet and exhaust. It took a second or third look and seeing the heading soaring to realize it is a fuselage with clearance for a wing. lol, that did make me laugh, and I see what you mean 😂 1 Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted May 13 Author Share Posted May 13 Balsa tips on, resisted temptation to shape and make them dingable. Used fus to mark out positions of wing bolts: Seemed easy 🙂 hmmm... Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted May 13 Author Share Posted May 13 Previously I've cut chunks out of the wing and then replaced with solid balsa, this time I'm trying biscuits 🙂 Quote Link to comment Share on other sites More sharing options...
Konrad Posted May 13 Share Posted May 13 Biscuits and a hot cup of tea?🙄 Sorry can't this too well, are the Biscuits glued only to the LE & TE only? I don't see any bonding to the wing skins. Is this by design? Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted May 13 Author Share Posted May 13 (edited) Aye, good point, got lazy so in places they fit into the foam at the moment. I'll clear a bit out more foam round the bolts and inject in some micro-ballon/epoxy mix in-between the biscuits and the lower skins where needed. The rear mount is pretty tight round the bolt location so won't need much if any epoxy. The front mount will definitely need some below the biscuit on one side (as I only plan to use one bolt at the front). We'll see if this is easier than making the biscuits the 'proper' shape 🙂 The wing is mid-mounted which means that the bolts are really only needed to stop the rear fus section moving away from front fus section, or sliding off to either side; the fus does not need to be squeezed against the wing as tends to happen in a high-wing (or low wing) glider. Also, the large carbon tube down the length of the underside of the fus, keeps all the components in line and the large overlap between front and rear wing sections means that they only need held together (hence the bolts at both ends). The other function of the front biscuit is to reinforce the LE and so it will be well epoxied to it. We'll see how it goes with the biscuits glued into one wing - then I'll think more about which bits need to be reinforced 😮 yup - being a bit lazy in my design thinking, but it'll be all right on the night 🤞 😮 🙂 And thanks for looking out for me and posting your comment 👍 Edited May 13 by Mike Chantler 1 Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted May 19 Author Share Posted May 19 (edited) Slow progress as have been faffing around a bit. Getting near to varnishing stage, so as the ailerons are pretty thin I've been looking at the effect of varnishes on veneer: Water-based varnish definitely makes it curl! 😮I may well use a solvent based varnish on the wings - but will need to watch I don't melt the foam! I also experimented with shaping hardwood to fit the void above and below the front biscuit, decided this was a bad idea as no matter how careful I tended to distort the unsupported skins a wee bit, so filled them with 20 min epoxy instead (potentially very messy even if you use using syringes etc.) The thing I really didn't like was that even the epoxy tended to distort the skins a little (1/2 mm or so) - not a big deal until you come to join the wings and you are using the edges of root sections as the datum 😞 I did have the beds but like to use the root sections to double check by running a finger across the seam. Nearly forgot the dihedral brace as I was putting it all together! We'll see if the wings each now have the same AOA on its maiden! Edited May 19 by Mike Chantler Quote Link to comment Share on other sites More sharing options...
Konrad Posted May 19 Share Posted May 19 Try to avoid solvent based varnishes as they will dissolve the core foam should the vapors contact the foam. When varnishing do try to use opposing force to counter the curling tendency. It is best to use “dry” coats at first. If a curve develops you can iron out the TE with an iron and some low level heat and counter force. 1 Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted May 24 Author Share Posted May 24 Used 3 coats Hycote spray lacquer on aileron areas, predicably this stuff destroyed test foam when sprayed really close, but did not get though veneer when sprayed 2 passes x3 @ 8". However, it did not prevent brush-on water-based acrylic curling test piece(maybe didn't leave spray to dry long enough). Used the brush-on stuff for the rest of the wing as I got really bored/frustrated using the spray.🙄 For the first time I used gradually increasing grits as all the videos tell you too - made the process real quick - duh, should of been doing this years ago 🤔🙂 Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted May 24 Author Share Posted May 24 Added 1oz aramid wing bandage as there is very little room for anything thicker, we'll see if this is strong enough when it flies! Started scary part: cutting/hinging the ailerons, followed Speedsterden vid on RCgroups ArtHobby thread this time. Liked the clearance the hacksaw gave at the ends but they needed tidying up a bit (tape does help stop the tear-out). Cutting from the non-hinge side first definitely made aligning hinge and top-cuts easier 🙂 And I really liked the idea of using a blade with the tip ground off to stop it damaging the thin aramid hinge. 🙂 Quote Link to comment Share on other sites More sharing options...
Mike Chantler Posted May 24 Author Share Posted May 24 (edited) Just started on under/over linkages Servo frames were too good a fit(!!) and would not release servos once they were in the wing so had to dremel a bit of clearance. Carbon tops and bottoms add 2 x 0.3 mm so had to adjust height. And put lead exit hole in wrong place initially! But mega-chuffed with the way they have worked out 🙂😁 Edited May 24 by Mike Chantler 2 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.