Mike Etheridge 1 Posted February 22, 2015 Share Posted February 22, 2015 C O' 's last Uproar has an OS 46 SF (?) and a tuned pipe as in the photograph. The OS has a throttle mixture control linked to a separate servo. I can confirm the OS powers the updated Uproar very well, but of course the earlier Uproar plan shows a Fox 29 engine. Quote Link to comment Share on other sites More sharing options...
David Davis Posted February 23, 2015 Author Share Posted February 23, 2015 My plan shows an ETA 29 and the overall weight of the model is shown as 89 ozs or about five and a half pounds. With a modern radio, mine will be much lighter of course. I'll start work on the fuselage later today. Quote Link to comment Share on other sites More sharing options...
Mike Etheridge 1 Posted February 23, 2015 Share Posted February 23, 2015 ETA 29 it is having checked the plan, best of luck with the fuselage! Here are some more details from the 1996 RCM&E magazine-I still have that bit of sponge that is wrapped around the receiver: Edited By Mike Etheridge 1 on 23/02/2015 14:47:25 Quote Link to comment Share on other sites More sharing options...
David Davis Posted February 28, 2015 Author Share Posted February 28, 2015 I have started work on the fuselage but I am left with something of a dilemma about which engine to fit. The model has a very long nose and when fitted with a Merco 61 required several ounces of lead in the tail plane to get it to balance properly. Currently all three of the servos and the RX battery are fitted at the rear of the wing seat, well behind the c of g. Chris's original engine was an ETA 29 which weighed about 7 ounces. My first choice of engine is an Irvine 36 which is my lightest engine at 12 ounces but would the model be too tame with such a small engine? An Irvine 46 would give the model a more sparkling performance but that weighs 18 ozs so are we straying into Merco 61 territory? I have the option of fitting an OS 52 four-stroke which weighs 16 ozs. I have a similar size engine in a Super 60 which powers it well enough. It would appear that I have the following options: To leave things as they are and try it with the Irvine 36. It's said to be a screaming demon so may give me the performance I'm looking for. Move at least one of the servos to the tail to compensate for the extra weight of a modern engine, and fit either the OS 52FS or the Irvine 46. ( I am reserving my new Irvine 53 for the glassed WOT 4!) As 2 but fit a 61, add lead to the rear and remember that the wings are banded on so fly it accordingly. I don't want it to stooge around like a trainer, so which one should I fit to the Uproar if I want a spirited performance? What is the consensus? Quote Link to comment Share on other sites More sharing options...
kc Posted February 28, 2015 Share Posted February 28, 2015 Nobody else seems to have offered an opinion........ Maybe another alternative is to saw a bit off the nose and mount one of the heavy engines without adding tail lead....... perhaps just try a temporary lashup to see how much would need to be sawn off? Quote Link to comment Share on other sites More sharing options...
Mike Etheridge 1 Posted February 28, 2015 Share Posted February 28, 2015 I must say that the OS 46 with the tuned pipe does give plenty of power and is quiet at high level. Perhaps the tuned pipe which is quite heavy has an influence on the C/G, however I am not aware of any ballast in C O's plane but then I have not accessed the rear of the fuselage. Quote Link to comment Share on other sites More sharing options...
Mike Etheridge 1 Posted February 28, 2015 Share Posted February 28, 2015 Another Uproar picture at Bartons Point club field. Quote Link to comment Share on other sites More sharing options...
David Davis Posted March 1, 2015 Author Share Posted March 1, 2015 I was wondering whether the 1996 version has a shorter nose than the earlier one. On my model, the distance between the leading edge of the wing and the top of the firewall is 19.5 cms. The other thing to bear in mind is that the tailplane on the 1996 model is fully sheeted and therefore likely to be heavier. If it's convenient Mike, could you measure the same distance on your model? Finally, even though it's a bit incongruous on a vintage model, I have incorporated a hardpoint in the fuselage structure to enable the use of a tuned pipe. Quote Link to comment Share on other sites More sharing options...
Mike Etheridge 1 Posted March 1, 2015 Share Posted March 1, 2015 David, Having checked both the original and revised (1996) plans, the dimensions are 251 mm and 254 mm respectively. This is the distance from the face of the bulkhead which the wing locates against and the port side nose cheek as described on the plan. Even though there is a 3 mm difference such that the revised model nose appears longer, I would say that the dimension has not changed and that the discrepancy is a result of the plan printing process. Quote Link to comment Share on other sites More sharing options...
David Davis Posted March 1, 2015 Author Share Posted March 1, 2015 Thanks for taking the trouble Mike. As the same measurement on my model is only 195mm, both on the plan and on the actual fuselage, it would appear that the 1958 plan had a shorter nose. I understand that the Irvine 36 was quite a powerful little engine if fitted with a 9 inch prop so I'll give it a go with that one first. The wing's still with the sign-writer anyway. Quote Link to comment Share on other sites More sharing options...
David Davis Posted March 8, 2015 Author Share Posted March 8, 2015 Just a quick note on the Uproar renovation. I had to remove the servo tray to get access to the starboard lower longeron because the glue joint had failed between the longeron and the side sheeting. I ran a bead of cyano along the joint, squeezed the parts together by hand and the job's a good un! Marvelous stuff cyano! I then epoxied the servo tray back into place, covered the nose area, and fitted a nylon mount for the Irvine 36. I found that I had some lithographic plate in the loft so I've made a metal tank-bay cover for it, something like the original The wing is back from the signwriters, but I still have a number of small tasks to do. I have to rig up a throttle push rod, fit the tank, make up a longer tail wheel leg, repair and recover the tailpane and glue it to the fuselage. It should be ready for a flight-test next Saturday when the winds are forecast to fall lighter. Pictures to follow. Edited By David Davis on 08/03/2015 16:54:08 Edited By David Davis on 08/03/2015 16:54:33 Quote Link to comment Share on other sites More sharing options...
David Davis Posted March 13, 2015 Author Share Posted March 13, 2015 I have stripped, repaired and recovered the tailplane. It looks alright providing you don't look too closely. I'm a master with the light-weight filler! Quote Link to comment Share on other sites More sharing options...
Martyn K Posted March 13, 2015 Share Posted March 13, 2015 Looking good David. I see no filler, lightweight or otherwise M Quote Link to comment Share on other sites More sharing options...
David Davis Posted March 13, 2015 Author Share Posted March 13, 2015 The second last picture clearly shows the lightweight filler before I sanded it away! The model still requires the installation of the aileron pushrods and the throttle pushrod, the elevator pushrod needs to be connected up, the tank needs to be installed, the tank cover secured, the receiver and its battery need to be fitted and bound, a decent tail wheel needs to be fitted and there are a few other matters requiring attention but I should be able to maiden it on Sunday if it's not too windy. Having got it to this stage who can resist assembling it to see what it's going to look like? Certainly not me! Oh and the thing on the end of the silencer is an Irvine Mouse, regrettably no longer made. Quote Link to comment Share on other sites More sharing options...
Mike Etheridge 1 Posted March 13, 2015 Share Posted March 13, 2015 Looks fine to me---Just Engines can provide the equivalent of the Irvine Mouse, I have bought two such add-on silencers from them to reduce the sound output from two Enya 45 powered planes. Quote Link to comment Share on other sites More sharing options...
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