Simon Chaddock Posted July 16, 2017 Share Posted July 16, 2017 Colin. That is looking very nice indeed. Seeing those pictures you forget that the Chippie actually has quite a high aspect ratio wing. Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted July 16, 2017 Author Share Posted July 16, 2017 Thanks Simon. It does, it looks quite efficient. This one has been hanging around long enough, it has to be finished now. Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted July 17, 2017 Author Share Posted July 17, 2017 I've managed to do some more rubbing down and "Ezekoting". Nearly ready for painting. Also,painted matt black inside the cockpit area and put the instrument panels in. Other things mean I won't be able to touch it tomorrow, but hopefully can do some more on Wednesday. Quote Link to comment Share on other sites More sharing options...
Dwain Dibley. Posted July 18, 2017 Share Posted July 18, 2017 Excellent work Colin, It's getting very close now to the finish line. I love those instruments too. D.D. Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted July 18, 2017 Author Share Posted July 18, 2017 Dwain, you're very kind, although compared to your Moth mine will probably look a bit scruffy. Congrats on that first flight, you must be chuffed to bits. I would be. Quote Link to comment Share on other sites More sharing options...
Dwain Dibley. Posted July 18, 2017 Share Posted July 18, 2017 Thanks for that Colin, yes I was rather pleased.... D.D. I think we qualify for M.A.S. ..........the mutual appreciation society...... Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted July 18, 2017 Author Share Posted July 18, 2017 Being perfect makes life so hard, doesn't it? Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted July 19, 2017 Author Share Posted July 19, 2017 Any ideas anyone on the best place to conceal the switch on my I/c engined version? I hadn't thought about it until now. Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted July 19, 2017 Share Posted July 19, 2017 How about the old technique of using a length of piano wire to operate the switch. Could hide it as a gun sight etc? Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted July 19, 2017 Author Share Posted July 19, 2017 Danny, thank you. I'd forgotten that one, done it years ago! Not sure the gunsight idea would be appropriate on a Chipmunk, but I'll think of something. Quote Link to comment Share on other sites More sharing options...
Tony Richardson Posted July 19, 2017 Share Posted July 19, 2017 Colin how about a magnetic switch nothing on the outside? Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted July 20, 2017 Author Share Posted July 20, 2017 Hi Tony, that's new to me, what is your idea? Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted July 20, 2017 Author Share Posted July 20, 2017 Looking now at the front end. If I use the standard exhaust it will be outside the cowl and look a mess. The answer looks to be a turbo-header made in the USA that turns 90 degrees and keeps the muffler in very tight. They are on a thread here somewhere and get good reports. Just Engines is a stockist, although I don't see the 10x75A that I need for the OS62FV in their web-site. I've sent them an email. If I use one of those I will need a decent means of getting the exhaust out of the cowl in a reasonably scale fashion. I've got some 20g brass sheet and tube plus some silver soldering rods and flux, so I might be doing something bespoke. Quote Link to comment Share on other sites More sharing options...
Tony Richardson Posted July 20, 2017 Share Posted July 20, 2017 Colin it is a product made by Zepsus in Denmark, I am not sure who stocks them in the UK Here Edited By Tony Richardson on 20/07/2017 20:41:01 Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted July 20, 2017 Author Share Posted July 20, 2017 Hi Tony. Very interesting, I'll find out more. A couple more shots here. After several coats of Ezekote I thought I'd try a flash spray of aluminium. As more or less expected with Depron, it isn't brilliant. After some detail rubbing down, I'll respray with grey primer and do it properly. In the meantime I'll start to sort the wing out. Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted July 23, 2017 Author Share Posted July 23, 2017 While I'm waiting to sort out the exhaust detail I've gone back to the wing. Although I proved that you can dope a covering onto Depron if you protect it first with Ezekote etc, making the shrouds from Depron was stupid because when the doped silk shrunk it buckled the Depron and pulled it away. These photos show the problem. I cut the shrouds off and carefully stuck the remaining Depron back down. To tidy up the mess along the underside trailing edge, I decided to glue a 6mm wide strip of 1/64" ply along it. Next I made new aileron shrouds again using 1/64" ply, backed with a 3mm balsa strip. Looking promising, flap shrouds next. I've damaged the silk in places and need to repair it. I'm going to dope tissue on top of it, I'll try a test area first. Quote Link to comment Share on other sites More sharing options...
Gordon Whitehead 1 Posted July 24, 2017 Share Posted July 24, 2017 Hi Colin Mick Reeves Models sells stainless steel bendy pipe in various diameters that might help with your exhaust problem. He also sells low melting point silver solder and flux for joining it to other things. You'll find these on the accessories page along with a couple of add-on dumpy silencers. For those using a Laser engine for their Chippy, Mick has the pipe equipped with ends to fit the Laser exhaust port, which Laser have now stopped selling. On a completely different tack, how about the Chippy as a cold war spy plane? Re-reading the book I mentioned earlier I decided to google a reference within it to a couple of operations called "Schooner" and "Nylon" and came up with this intriguing account: https://www.16va.be/vols_brixmis_part1_eng2.html Mention is made of evading a couple of marauding Hind gunships by knife-edging the Chippy between them ... eeek! Gordon Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted July 24, 2017 Author Share Posted July 24, 2017 Thanks Gordon, I'd forgotten about the useful stuff that Mick offers, the answer might be there. I'll have a look. I did email Just Engines on Thursday about the Turbo Headers that they list, very disappointed to have not received a reply when I had expressed a wish to place an order! I've read about the use of Chipmunks for spying in the Cold War, an interesting option as a finishing choice! However, the plan so far is to reproduce WP848, the plane I flew in as an ATC cadet from RAF Waterbridge in 1961. We'll get there! Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted July 28, 2017 Author Share Posted July 28, 2017 Just noticed that my previous post said RAF Waterbridge, don't know how that happened, of course it's Waterbeach. Time has been a bit limited in the last few days, but I've finished sorting out the aileron and flap shrouds using 1/64" ply and they're done. I started to experiment with tissue on top of the silk on the wing but ran out of dope, so I must buy some more. I've ordered a Turbo Header exhaust from Just Engines, hoping that it will arrive in the morning because later in the day we're going on holiday for two weeks, so things will stand still until we get back. This is coming along well now, I've become optimistic about it and it looks promising. Quote Link to comment Share on other sites More sharing options...
Nev Posted July 28, 2017 Share Posted July 28, 2017 Looking good Colin. Surprising how a little paint makes all the difference and gives you a sense of the finish line. Nev. Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted July 28, 2017 Author Share Posted July 28, 2017 Thanks Nev, on the home run now. Quote Link to comment Share on other sites More sharing options...
McG 6969 Posted July 28, 2017 Share Posted July 28, 2017 Maybe a few quick words of wise advise needed here, Colin. If the well earned port or sangria doesn't help you to get a proper sleep during your holidays, a fully working trick is to start counting the rivets of the WP848 fuselage... Enjoy your time over there. Cheers Chris Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted July 28, 2017 Author Share Posted July 28, 2017 Thank you Chris. As a drag reducing measure I have decided that my Chipmunk will be flush riveted, so I don't have that option. Also as the itinerary includes Bruges, Copenhagen, Stockholm, Tallin, St. Petersburg and Berlin Rostock, I won't have a clue where I am most of the time and whichever form of alcohol I consume between Leffe Brun and neat Vodka will only add to the confusion. What's more, current political trends could see WW3 kicking off as I arrive in Russia and I will be thrown into the Gulag. If it can possibly happen, it will happen to me. Story of my life. If I am so incarcerated I bequeath my Chipmunk to you. Undoubtedly you will do a far neater job of it than I will, so my disappearance could be doing the world a favour. Just send me a hot water bottle and a pair of woolly socks. Quote Link to comment Share on other sites More sharing options...
McG 6969 Posted July 28, 2017 Share Posted July 28, 2017 ... well, as a naive novice, I thought "flush rivets" could be counted as well. ... and of course I was presuming you were heading to sunny Spain. No danger then with only well known 'spirits', no need for hot water (unless at teatime after the siesta), no "woolly socks" either.... Anyhow, if you're heading to Bruges, forget about the Leffe Brune and try to obtain a genuine 'West Vleteren' abbey beer. I really mean this. You'll be happily surprised and it will help you forget all the other stuff you could unfortunately absorb during the remaining part of your trip. If not, I'll do my utmost to take care of your Chippie baby. Enjoy Cheers Chris Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted August 14, 2017 Author Share Posted August 14, 2017 After two weeks away I can get back onto the Chipmunk. Following a tip-off from Tony Richardson, I have bought a Zepsus magnetic switch, 15amp capacity. With this I can switch the radio off externally by swiping with a magnet, so no unsightly external switch is necessary. Also, the Turbo Header makes it possible to fully enclose the silencer. Excellent. I can fit a flexible extension to take it outside of the cowl scale fashion. However, as mentioned before I'm going to have a go at silver soldering a secondary expansion chamber from 20g brass, with a scale outlet pipe. My reasoning is that I'm looking for a reasonably realistic exhaust note. Although a fan of electric in small to medium size models, I'm not so keen on the larger sizes. Also, they sound very wimpy and weedy and carting sound systems around doesn't appeal to me. The firing frequency of a model four stroke single turning over at about 8000/9000 rpm is actually about the same as a full size four cylinder four stroke turning over at 2,000/2,250 rpm, about right for the Gypsy Major. The lack of scale effect is a function of noise volume and tone. Increasing silencer volume blends and deepens the exhaust note, so I'm going to try and do that. Wish me luck. Quote Link to comment Share on other sites More sharing options...
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