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Tim Flyer10/10/2019 14:31:20
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1073 forum posts
194 photos

One other thing I might mention is that I haven’t yet totally finished the wing tip and leading edge profiling. I only partly completed this as due to its large size it’s very easy in my small workshop to slightly damage the surfaces so I wanted to try and do the finishing at the last stage . It’s also worth noting that the centre wing profile needs to match the wing capping on the fuselage, plus the front centre section of the leading edge needs to be flat where in meets the fuselage and wing dowel recess area. That’s why I have been conservative with sanding so far .

Tim Flyer14/10/2019 14:21:49
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1073 forum posts
194 photos

Here are the flap and ailerons cut out . It’s not too difficult. Firstly a narrow cut is made and widened slightly along the line between aileron/flap spars with a scalpel on both sides followed by carefully running the razor saw along the line to separate. I purposely did not finish the trailing edge as the square edge makes sanding and alignment easier at a later stage . The same goes for the leading edge and wing tips . Leaving them square on the edges protects them and will allow easier blending in later .

I will be using flat hinges which makes the flap installation easier, with no recessed hinge line required.

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Ron Gray14/10/2019 17:55:28
1480 forum posts
363 photos

Hi Tim, you're doing a grand job there!

Rich too15/10/2019 04:58:11
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3052 forum posts
1070 photos

Well done Tim, and keep posting yes

Tim Flyer15/10/2019 07:26:05
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1073 forum posts
194 photos

Hi Ron and Rich . Thank You very much for the encouragement. Much appreciated. This is my first large 1:5th scale build so it certainly is a new challenge in terms of its size. In some ways the bigger build is much easier as it’s far less fiddly than a smaller plane. The Perma-Grit tools and razor plane are coming in very handy. The other tools I have used are aluminium square rods. These are great as straight edges and for clamping. I bought them on line a while back when I was bus new extra long wing tube for my Hurricane. The aluminium supplier wanted just abou £5. For a long length of wing tube but their minimum order was £20 so I added a number of aluminium angle lengths and tubes that come in really handy. A whole load only cost me £25😊

Ron Gray15/10/2019 09:09:00
1480 forum posts
363 photos

Good tip about the alloy rods, I have a metal supplier quite close to me so may well pop along and see what he has in his spares bin, always come out with odd bits and pieces that 'may' come in handy!

Tim Flyer15/10/2019 10:53:04
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1073 forum posts
194 photos

Cheers Ron . Yes the alloy tubes and angles are really useful. They were great for the wing sheeting. I have just cut out the ailerons and flaps . Fitting with correct gaps after capping always takes some time, and I’m being careful to make each flap the same size. One downside of building I have discovered is that aliphatic on the fingers makes my typing even worse ! 😊

Edited By Tim Flyer on 15/10/2019 10:54:17

Tim Flyer16/10/2019 13:19:55
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1073 forum posts
194 photos

Here are the flat hinges going in with help of Xcel hinge cutter . The profiling is done after hinging as usual ( otherwise slotting would be difficult) . The flap has a half angled profile as it just goes down. The aileron has the usual double profile . To profile more razor planing and sanding is needed.

Tim Flyer16/10/2019 13:23:10
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1073 forum posts
194 photos

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Tim Flyer16/10/2019 13:23:47
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1073 forum posts
194 photos

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Jon - Laser Engines16/10/2019 14:05:44
4834 forum posts
180 photos

Do you have your B yet Tim? If so you should join the stampe/tiger moth slot at wings n wheels next year. A chipmunk will be a nice addition

Tim Flyer16/10/2019 17:15:01
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1073 forum posts
194 photos

Hi Jon I’m afraid I haven’t got the B yet but hopefully will do it very soon ( next few weeks/ days) if the weather improves. We are having an instructor visit our club this weekend and hopefully we will get a test date arranged soon . 😊.

I have now finished the flaps and ailerons on both wings . I must say the Kavan flat hinges I bought from SLEC are very good quality and made the job easier. The flaps and ailerons are finally fixed after covering. As in all building labelling is important. It’s very easy to get mixed up otherwise. I label everything with a felt pen . I took time to get a satisfactory fit .. if perfection required that would have taken even longer , it’s always a “best guess” fit approach as covering film or paint tighten gaps considerably. Next job is gluing in the wing joiner to the right wing . The left side has the joining box with the two bolts .

Tim Flyer17/10/2019 11:02:48
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1073 forum posts
194 photos

0424e542-a67b-4567-be3d-4851235c8fc0.jpegToday I glued in the ply wing joiner into the right hand wing. Firstly I checked the fit . The ply joiner needed a little sanding to allow the inside ribs to but together. Luckily the wings were straight and the fit on both sides of the rib were ok so I didn’t need much extra work . The left hand wing is bolted to the joiner at the field via the two bolts accessed from the central left hand wing joiner pocket. The gluing in of the joiner into the right hand wing must be done carefully. Otherwise you might get a one piece wing!! I used some masking tape and was careful with the epoxy. The wing is very big and fills my small workshop( I had to have a tidy up too!) . Anyway for most of today I will have to leave the wing alone in there to give the epoxy plenty of time . I will not separate the wings until tomorrow to allow complete hardening. Hmmm maybe I will go flying 😉

Edited By Tim Flyer on 17/10/2019 11:03:40

Tim Flyer21/10/2019 12:10:49
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1073 forum posts
194 photos

Here is the tailplane and elevator construction now complete. I added small balsa gussets to the right and left aerodynamic balancers on the elevator. That was to avoid hangar rash as they are quite vulnerable to knocks. The instructions were a bit vague on the elevator jointing with the joiner wire and lite ply plates . I made them the hard way taking ages with balsa tongue joints. An easier way would be just to make the complete Balsa frame . Let it dry then sand to fit the reinforcing plates, rather than all the measuring and cutting I did ! 1e004638-7dd1-4ff6-895c-fb64ddd8c5c0.jpeg

Tim Flyer24/10/2019 13:26:13
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1073 forum posts
194 photos

I have finished off the tailplane and elevator now and sanded the elevator taper to the trailing edge. I haven’t sanded the tailplane leading edge in order to avoid unnecessary hangar rash before finishing.
Today I started the fin and rudder construction. That is fairly simple but also needs careful razor saw cutting. One small matter to note is to check part labelling . The instructions gave the wrong part number for the fin base , but the plan was correct. I have found it very important to check the dimensions of each required piece of wood before cutting to avoid mid labelling errors . The dimensions are conveniently listed on the back section of the instructions. The fin and rudder are now being left to set before sanding the curved profile.

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Tim Flyer25/10/2019 11:30:16
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1073 forum posts
194 photos

One slight difference between plan and instructions which I believe I have solved ( yet to be confirmed when I get to near completion of fuselage!) is the fin base . The plans show balsa parts “TC15” and “F34” beneath and the instructions call for part TC 13 which is actually a totally different sized liteply elevator support panel ( already used!) . Anyway it’s fairly obvious that the kit supplied balsa TC15 part actually combines part TC15 and F34 . I made sure when sheeting the fin I just covered the “TC15” area.
Next job is finishing the rudder adding balance weight and brass wheel tube

Tim Flyer28/10/2019 22:28:58
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1073 forum posts
194 photos

The last small “tweaks” of putting in the balancer weight and brass tube in the base have been done. The instructions are quite helpful and give good advice on using cyano to soak through pinholes after the brass tube is fitted. The tail wheel wire fits tightly and it’s also important to de-burr the bras tube before gluing in otherwise fitting the whe wire will be tough. The balance weight on the front of the rudder is apparently to reduce potential rudder flutter.

I’m looking forward to getting the fuselage started as is such a substantial size. For the last day I have been waiting for smelly paint to dry on my little Wot 4 that I repaired after a careless low level crash 😉. I must admit I totally hate painting! On this plane I plant to film cover , but will still need to paint the cowl and the wing fairings. I guess I will need to find some Oracover Red with matching red aerosols so there isn’t a bad colour clash between the main fuselage and cowling . Anyway painting is a fair bit later luckily!

Chris Freeman 329/10/2019 05:10:20
273 forum posts
355 photos

Very nice build, a Chipmung is a great aircraft. I had a Carl Goldberg one for many years and loved it. I have a scratch built airframe about the same size as this one that I need to finish, I used a Dynaflite kit as a basis for my one. I Have not worked on it in a year and a half but have decided that it must be finished. Thanks for the inspiration.

Tim Flyer29/10/2019 09:54:19
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1073 forum posts
194 photos

Thank you for your kind words Chris.😊 Finishing your scratch build seems a great idea. It’s hard not to get waylaid into other projects. I suppose my restricted size workshop prevents me starting too many projects, and this one almost fills it ! A Chipmunk is such a nice flyer and so much of a “practical scale “ plane that it really makes sense to “keep one in the fleet”.

Tim Flyer29/10/2019 13:27:31
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1073 forum posts
194 photos

I started preparing for the fuselage build this morning . Firstly I cleared the excess after run oil out of my Laser 180 before it spills all over the plan ! I then prepared the engine spacers . The width you need is clearly stated on the plan making it quite simple. I found a very useful short cut by using spacers I salvaged from an older wreck . Salvaging and reusing bits saves lots of time plus reduces waste! Dismantling of epoxy glued bits is incredibly easy using a heat gun! It saved me cutting and laminating new ply blocks. After a few minutes sanding I am left with two 22mm spacer blocks as required. The ply firewall is marked with an adjusted centre mark so measuring up will be easy. The engine will be mounted inverted but I will probably move it to around 4:30 to 5 o’clock so the fins are in line with the cowl intake. At this stage I’m also thinking about what exhaust I will use. Either stock laser or I might well fabricate a bendy pipe one which will give more choice on exit. There is a cooling outlet on the bottom of the firewall so I Will also consider the through flow of air out of that after entering through the front of the cowl . c24bb436-4801-4733-ab6d-0604e59f615d.jpeg

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