John Timmis Posted December 13, 2014 Author Share Posted December 13, 2014 Hi folks, Had 2 more fairly gentle flights this morning, Still 40% left in the battery. Managed to land & keep it upright on its wheels today so it can be done. Also found that it would taxi round quite well even with a fixed tailwheel. I thought some pictures of the battery bay might be of interest. The cowl is held on by 2 pegs at the rear together with 4 magnets on the bottom corners. It fits ok & is quite secure. The battery fits well back in its box. It is located by a balsa stop at the front & velcro underneath. A long balsa wedge goes on top to keep everything together. A velcro 'pigtail' under the battery makes it easy to remove. Cheers John. Quote Link to comment Share on other sites More sharing options...
John Timmis Posted January 6, 2015 Author Share Posted January 6, 2015 Hi folks Happy New Year to all Chippie builders & everyone else who follows the blog. The weekend weather was too wet to fly but at least I managed a couple of hrs in the workshop before I was driven out by the cold. Chippie no 2 has been started with the fin & rudder. I'm 3 months behind the rest of you so I need to catch up a bit. Still. experience & hindsight is a wonderful thing, & there is plenty of that here. Most of the build problems seem to be sorted now. I intend to have several building boards on the go at once so that progress can be made on several parts at the same time. At the last flying session a couple of spins were tried. Will try some more next time. At the moment all I can say is that it will spin nicely off a straight 1 g stall. Recovery is straightforward. More next time & some photos. Cheers John. Quote Link to comment Share on other sites More sharing options...
Nigel Day Posted January 7, 2015 Share Posted January 7, 2015 Good to hear your experience with Chippie no. 1 and that you're off on no. 2. I've still a good way to go so I suspect that your build will be useful. Quote Link to comment Share on other sites More sharing options...
John Timmis Posted February 2, 2015 Author Share Posted February 2, 2015 Hi folks Some progress has been made but with the temp in the workshop between 5 & 10 degrees through Jan its been slow. The photos show where we are today. The tail surfaces are ready to have the hinges fitted & then they can be finished. The fin LE was laminated from 4 x 1/16 balsa. The fuselage shells are both sheeted because I couldn't face all that planking again. It probably didn't save much time but the results seem ok & both shells are nice & rigid. The skins for the conical rear fuselage were glued up from tapered sections & then wrapped roud the frame & clamped. The ammonia trick was a big help here, I've not tried that before. The sheet sides on the lower shell were spliced at F8 where the taper starts. On the top shell, the inside of the cockpit walls wre lined with .4 mm ply as this area had proved prone to damage on the first build. A start has also been made on the motor / battery mount. Next up is a start on the wing. Cheers John. Quote Link to comment Share on other sites More sharing options...
John Timmis Posted February 2, 2015 Author Share Posted February 2, 2015 Hi folks Some progress has been made but with the temp in the workshop between 5 & 10 degrees through Jan its been slow. The photos show where we are today. The tail surfaces are ready to have the hinges fitted & then they can be finished. The fin LE was laminated from 4 x 1/16 balsa. The fuselage shells are both sheeted because I couldn't face all that planking again. It probably didn't save much time but the results seem ok & both shells are nice & rigid. The skins for the conical rear fuselage were glued up from tapered sections & then wrapped roud the frame & clamped. The ammonia trick was a big help here, I've not tried that before. The sheet sides on the lower shell were spliced at F8 where the taper starts. On the top shell, the inside of the cockpit walls wre lined with .4 mm ply as this area had proved prone to damage on the first build. A start has also been made on the motor / battery mount. Next up is a start on the wing. Cheers John. Quote Link to comment Share on other sites More sharing options...
Nigel Day Posted February 2, 2015 Share Posted February 2, 2015 Quick progress John. You'll be on to the rivets in no time. Quote Link to comment Share on other sites More sharing options...
John Timmis Posted February 21, 2015 Author Share Posted February 21, 2015 Hi folks A bit more progress has been made & I have now completed the frameworkk of the wing. This went together without too many problems & fairly quickly. I don't know if there is anyone else still to tackle the wing but for those who are interested , this is my build sequence. Having failed on 5 occasions to find any suitably hard 1/4 sq for the spars I decided to use pine. I bandsawed some strips & then sized them on the router table. It may be over the top but at least it's extra weight in the right place. !. Tabs were added to all the wing ribs. 2. The dihedral angle was set out on a board & using this as a guide both lower spars were glued to the front of the dihedral brace (B2). Then upper spars added & finally the second B2. 3. Strips of 1/8 glued to the lower edges of the trailing edge. 4. The ply brace parts (B3) were glued then tapered. A smoothig plane will do this job in about 5 min. 5. Set up the spar over the plan to build the right wing panel. I have a heavy steel cube (3 inch) to which the center of the spar could be clamped. This keeps it in place & perpendicular to the board . The spar tip was held down with a spring clamp. Starting with R1 & the TE, cyano the ribs in place. Take care that the spar booms are pressed down properly & that the 1/8 sq strip on the lower edge of the TE is properly located. 6. Turn the plan over & do the same with the other wing panel. 7. Add a false leading edge cut from 1/8 sheet. 8. Lift off the plan & then set it up level resting on the root ribs & the tabs. Check tha all is straight & level & then glue in B3 & B1. 9. Remove the excess wood from the edges of the false LE. I use a block plane for this followed by a sanding block. This is were my wing stands now. Next job will be spar webbing & then the top LE sheet. Cheers John. Quote Link to comment Share on other sites More sharing options...
John Timmis Posted March 21, 2015 Author Share Posted March 21, 2015 Hi folks Some pictures of the latest progress. Assembling the wing spar first worked well. I have beefed up the U/C fixing. Made up a simple profiling jig to sand the fuselage / wing joint. Weight so far is 2lb 3oz. Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted March 21, 2015 Share Posted March 21, 2015 That wing profile jig is a great idea John, I wish I'd thought of it. (Story of my life)! Quote Link to comment Share on other sites More sharing options...
John Timmis Posted April 24, 2015 Author Share Posted April 24, 2015 Hi folks It seems to have been very quiet on the Chippie front just lately. Perhaps everyone is out flying? My excuse is that I've been in USA for the last 4 weeks visiting family. Anyway, back now so hoping to make some progress. There are lots of small jobs to do but the main one now is to sort out the wing seating & fixings. The jig shown in the last post is a big help to what could be quite a fiddly job. I think that the wing will be fixed with bolts at the LE & TE, ( the way Danny did it). After that the dreaded wing fairings. Some photos next time. Cheers John Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted April 24, 2015 Share Posted April 24, 2015 Hi John. I was progressing with mine up to last weekend, but flew out to Spain on Monday with my wife for a break, back on 08 May. I'll get straight back onto it when I'm home. Finished sorting out ailerons and flaps, so hoping to speed up a bit now. Quote Link to comment Share on other sites More sharing options...
onetenor Posted April 24, 2015 Share Posted April 24, 2015 I think small balsa sizes cannot retain their moisture which lets the cellulose cell walls collapse .Just A GUESS. spar size problem. Would Obeche or Birch have done in same sizes ? Quote Link to comment Share on other sites More sharing options...
Terry Walters Posted May 15, 2015 Share Posted May 15, 2015 Great idea with the wing joint profile - that's idea filed away in my head John - thanks Quote Link to comment Share on other sites More sharing options...
John Timmis Posted May 29, 2015 Author Share Posted May 29, 2015 Hi again, Well it's good to be back. There is good news & there is bad news. The good news is that ,after a couple of unavoidabe breaks , progres is being made with chippie no build. Its steady progress rather than spectacular but at least it's in the right direction. Main things are : The wing fixings ar done (2 socket head screws used), The wing fairings are started (a tricky part of the build & the plan isn't very much help here, in fact I think that the plan is just wrong), Some work has been done on the tail surfaces & the rear fuselage fairing ( only small jobs) so next thing will be to sort out linkages & servos. Cheers John I'll mention the bad news next time. Quote Link to comment Share on other sites More sharing options...
John Timmis Posted June 23, 2015 Author Share Posted June 23, 2015 Hi Folks Here we go again. Well, the bad news was that chippy no 1 came to grief. The pictures show the results of a landing accident. All was under control, flaring out to land , no more than 18" off the ground, when suddenly the right wing dropped & the resulting cartwheel broke the fuselage in two. There was no other damage to the rest of the model. Obviously its pilot error ( isnt it always) though I was a bit suprised because although it had shown quite a sharp stall in the past, with flaps down the stall was a much more benign affair. Anyway, take care, because even Chippies can bite. The repairs are now finished & its ready to fly again. I'll show some repair pictures next time. Can anyone tell me how to insert photos into the text in a proper order? Cheers John Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted June 23, 2015 Share Posted June 23, 2015 Hi John good to have you back on the build Oh dear that looks a bit broken, glad to hear the repairs went okay though I am not sure what you mean with image position? I just type and then insert a piccy, then move the cursor to the lower right corner of the inserted pic, (If you imagine the pic is a character, you need the next character position to the right) then hit enter and continue typing up to the next desired insertion point? Moving them can be a bit of a mare, I tend to delete and re-insert if they get in a mess Cheers Danny Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted June 23, 2015 Share Posted June 23, 2015 Hi John, that's rotten luck with that landing, but I'm glad to hear it's repaired again. On photos, as Danny says, it's just a case of having the cursor where you want your next photo, before clicking on the button. If you find that you can only "highlight" a picture that you've already inserted but can't get the cursor lower, then with the last photo still highlighted (a funny shade of blue all over it), press the right arrow button. That puts the cursor to the right of the photo. Then press the enter button and the cursor will move to one line below the last photo. Quote Link to comment Share on other sites More sharing options...
Andy Muckley Posted June 23, 2015 Share Posted June 23, 2015 Bad luck there John, glad you got it repaired though Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted June 23, 2015 Share Posted June 23, 2015 Perhaps I will be glad of the wash-out I've got built into mine, it will be interesting to see how it stalls. I feel a bit guilty for not getting straight back on with mine when it is so far along, but I couldn't resist having a bash at the B42 project that formed in my head. That is coming along quickly and I'll get back onto the Chipmunk ASAP. Edited By Colin Leighfield on 23/06/2015 23:46:38 Quote Link to comment Share on other sites More sharing options...
John Timmis Posted June 24, 2015 Author Share Posted June 24, 2015 . Hi Folks Had 4 good flights with the repaired chippy this morning. Stalling at a safe height gave a sudden wing drop & entry to a spin. High rates were used on the elevator. I suspect that the landing accident may have been due to high rates being inadvertently selected. Most crash damage can be repaired & if you like the model & enjoy flying it it will be well worth the effort. It's always much quicker & cheaper than building a replacement. First step is to get the broken parts together & aligned properly. In this case that was easy & a few squirts of cyano had things back in place. At this stage it does't need to look pretty so long as it is straight. Use any method you can to achieve this. Next , check that the wing still fits. Now you can start to replace the damaged wood bit by bit. If you replace like with like & the splices are well fitting then it should be as good as new. Try to think what is primary structure & what is secondary. The standards for full size splice repairs in wooden aircraft are 1:15 for pine &1:12 for ply. You won't achieve this with balsa but you get the idea. I did the repairs in this order. 1 The crutch members . 2 top decking . 3 Lower fuselage sides using laminations of 1/8 as per original. 4 secondary structures (wiing fairing etc). Cheers John Quote Link to comment Share on other sites More sharing options...
John Timmis Posted June 24, 2015 Author Share Posted June 24, 2015 . Hi Folks Had 4 good flights with the repaired chippy this morning. Stalling at a safe height gave a sudden wing drop & entry to a spin. High rates were used on the elevator. I suspect that the landing accident may have been due to high rates being inadvertently selected. Most crash damage can be repaired & if you like the model & enjoy flying it it will be well worth the effort. It's always much quicker & cheaper than building a replacement. First step is to get the broken parts together & aligned properly. In this case that was easy & a few squirts of cyano had things back in place. At this stage it does't need to look pretty so long as it is straight. Use any method you can to achieve this. Next , check that the wing still fits. Now you can start to replace the damaged wood bit by bit. If you replace like with like & the splices are well fitting then it should be as good as new. Try to think what is primary structure & what is secondary. The standards for full size splice repairs in wooden aircraft are 1:15 for pine &1:12 for ply. You won't achieve this with balsa but you get the idea. I did the repairs in this order. 1 The crutch members . 2 top decking . 3 Lower fuselage sides using laminations of 1/8 as per original. 4 secondary structures (wiing fairing etc). Cheers John Quote Link to comment Share on other sites More sharing options...
John Timmis Posted July 14, 2015 Author Share Posted July 14, 2015 Hi folks It was a great pleasure to meet Danny at Greenacres last Sun & an inspiration to actually see his fabulous Chippy. We all certainly have a standard to aim for. Thanks Danny. Chippy no1 Has had about a a dozen flights since its repairs & seems none the worse for its time in the workshop. Chippy no 2 is making a little progress. A number of small jobs have been completed which taken together have moved the project along. A steerable tailwheel has been sorted, linkages have been installed in the fuselage & wing & the motor mount started. Still have to finish the cap strips & shrouds on the wings , also the wing fairing. Wokshop time is a bit limited just at the moment but 'little & often' keeps things moving forward. Cheers John. Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted July 14, 2015 Share Posted July 14, 2015 John it was a real pleasure to meet you too, let's hope one day we can send all these Chippys aloft together at a future Fun Fly It is the reports of yours flying so well that keeps my spirits up. Can you remind me the weight of yours and how much power you have? Cheers Danny Quote Link to comment Share on other sites More sharing options...
John Timmis Posted July 23, 2015 Author Share Posted July 23, 2015 Hi folks Not very much progress made . This is mainly due to the annual visit of grand children from USA.. Next job is the flap & aileron shrouds, after that I will just have to join the fuselage halves. Danny, in answer to your question: the weight of my 1st chippy is 7lb 15 oz ready to go. Power train consists of: 6s , 4500 Dynamic battery , 70 amp esc, motor is a Lightning 4205 from Flighloft , 650kv, rated 1150 w. The motor takes 1075w on a 13x4 prop at full throttle. Its far more power than necessary ( it is like a poor man's spitty) but even at 8 lbs it will throttle back & fly quite slowly. Off topic, but after seeing your Hurricane at Greenacres, I bought the plan while at Cosford last Sat. So thats the next project sorted. Cheers John. Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted July 23, 2015 Share Posted July 23, 2015 Great news John and thanks for the power and weight info You will enjoy the Hurricane, if you need a set of exhausts let me know? I know Martin wants a set too, wont be soon but I can add you to the list Cheers Danny Quote Link to comment Share on other sites More sharing options...
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