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[bert baker]

Plane was a damaged and dumped in the club hut for a anyone with some glue to repair

I re built it on the cheap and have been using a Laser 150,, absolutely perfect match,,,

[bert baker]

Deleted double posted 

Edited By bert baker on 22/04/2018 13:56:40

[Gordon Whitehead 1]

Thanks for the kind comments guys. There's no doubt that a dummy radial as on the Stearman and Jungmeister with a slot to direct air through the 155's cylinder fins would greatly improve the looks, as well as providing the ideal cooling for the engine. In practice I've not had a problem with overheating in radial cowl installations like this so didn't worry much about it. There's a fair sized annular gap between the rear edge of the cowl and the fuz proper, which appears to be extracting hot air satisfactorily for now. One thing I did was incorporate a dummy air scoop to direct cool air to the carb

Made from litho plate the lower wall extends inside the rear cowling and up between the carb and silencer to help to isolate the carb intake from the hot air whizzing round the silencer. The scoop did end up smaller than I expected, especially when the carb needle ended up passing through the middle of it, but it might make a difference.

An excellent idea I pinched from the Great Planes bipe kits was the carry handle which fastens onto the centre-section struts and incorporates storage for the interplane struts and the inter-aileron link wires.

That's a lovely photo of your Jungmeister, Steve. Propwise I have a couple of 17x7's and a 17x8 waiting for trial next time out. The 17x7's are Turnigy wood. Dirt cheap, quite a thin aerofoil section, well finished and balanced, I don't know whether to expect great things at the price but worth a punt. One has a conventional blade shape, the other is scimitar-shaped so that's even more of an experiment. The 17x8 is an APC.

Regrettably it rained this morning Tom so spoilt the festival somewhat until the sun came out around midday. We went yesterday afternoon in blazing sunshine and had a proper ice cream from the card shop on the corner of Welles Street - I've never liked that Mr Whippy gloop sold at fairs etc.

Cheers

Gordon

[Geoff S]

That really is a lovely model, Gordon. I like bipes but yours is something special. I hope we see it at Ashborne in the autumn on our scale fly-in.

My own modest bipe build (DB Cirrus/Gypsy Moth) is continuing and will sport your sprung undercarriage design.

Geoff

[Gordon Whitehead 1]

I'll definitely attend the Ashbourne event Geoff. I read your u/c thread, and immediately surfed Ebay for springs suitable for u/c's; there seemed to be an abundance, so thanks for that tip!

Gordon

[Gordon Whitehead 1]

Posted by Chris Walby on 14/04/2018 21:26:36:

Seagull Dual Ace with twin Laser 70's,

Major result for me, comes in just under weight and no added lead ballast (RX batteries are behind the canopy).

Taxi tests complete, minor work on throttle linkage and then it will be maiden time!

Heck! I've just googled the kit and if yours has come in at under the stated 11lb auw you'll surely have a rocket ship there, Chris, it's so sleek. The spec quotes a pair of .46's!

Gordon

[Chris Walby]

Gordon,

There are a couple of reasons for picking the Dual Ace, one its a relatively cheap airframe and secondly I need experience of flying twins before the engines move on....So when I saw people were putting lead in the nose of the Dual Ace, I thought it could stand a couple of nice Lasers!

I as am relatively new to the hobby and thus seek the advice of those that have the knowledge, expertise and support to help me avoid mistakes. Jon at Laser engines has spent far more time than he needed to discussing engine installation etc to make this a pain free install and hopefully I'll be able to do it justice.

I am slowly coming to the conclusion that "excessive" weight from 200g to 6Kg (the Vulcan) models just makes life more difficult in every respect! Worth having a read of David Mellor's thread on Model Vulcan Design, but to say with twin 70's the Dual Ace will never be light, although should penetrate the sky!

PS, for those with a need for speed they could go to another flying site that does not have the 82dB limit....and run it in the unrestricted settings, but for me its flight time for me and the Lasers (can you wear them out?)

[extra slim]

With the lovey weather this weekend, it saw a somewhat emotional outing of my DB Bi Stormer, bequeathed to me after the recent passing of one of mine and my dads dear friends, who tolerated me when I was a cocky teenager, down at the flying field. It originally flew with a merco 61, but I dropped in a laser 75, and my clubmates all agreed, a perfect match, and a lovely combination. I think our friend would approve.. lovely.

[Stuphedd]

Hi Extra Slim ,

I recon that airframe must be in the region of 35 years old at least ! And I am sure its previous owner and builder would be very pleased to see it flying once more !

Pete

[Ron Gray]

A Great Planes U Can Do, heavily modified to lower the fuel tank so that it is in line with the carb inlet. I had planned to use a Laser 100, and still will when they are back in stock (Jon!!!) but in the meantime it's a second hand 80 that's in there. Hoping to maiden it tomorrow.

[Chris Walby]

Ron, That looks superb!

Do let us know how what the build was like, was there a need to move the bulkhead back etc and is the AUW as spec?

And of course how the maiden goes.....

[Ron Gray]

Build was fairly straightforward apart from the tank location. As designed / sold, the fuz has a sloping ‘exhaust tunnel’ from the bulkhead back to the u/c mount and the fuel tank is designed to be mounted above this in the top half of the fuz. This is no good for an inverted Laser as the tank outlet is about 40mm too high so I had to remove the ‘tunnel’, infill the bulkhead, cut out a fuz former and brace it higher up, cut out a new fuel tank neck support hole, add the fuz bottom cover plate and whilst I was there I also added strengthening to the u/c mounting former plus the metal strap you can see in the photos. I also replaced the aileron metal pushrods with carbon ones. One of the biggest headaches was the throttle control, due to the position of the carb throttle arm and the throttle servo there is about a 60mm difference in height, I did think about trying to mount the servo closer to the carb but there wasn’t the space so in the end I used a heavy duty snake which seems to work ok. I did also toy with using a rudder pull / pull system but reverted to the designed rear mounted servo.

The bulkhead’s position did not need changing only had to add the infill piece as mentioned above. I changed the spinner from the supplied plastic one to an alloy job.

I didn’t weigh it before I loaded it into the ‘van for tomorrow’s flying session so will have to do that when I get back. On the subject of weight, I thought that it might be tail heavy with 3 x full size servos mounted under the tailplane together with the long moment arm the fuz design gives so I installed a 3000mha 2s LiFe battery hard up against the rear of the bulkhead (mounted horizontally). But when I checked it out it was actually a bit nose heavy so I’ve moved the battery back by about 30mm. We shall see how it handles with that configuration tomorrow.

[Chris Walby]

Thanks Ron for the info as my two laser planes needed next to nothing (15g on the tail) or no weight to get C of G, the other interesting thing is that the first (BH Speed IMHO flies "better" with IC than when it was electric).

Once again thanks for your information and best of luck tomorrow.

[Ron Gray]

Just took it out of the 'van to weigh it (it was nagging me!), AUW 3.5Kg so slightly heavier than designed weight. I could possibly shave some of that off by reducing the size of battery and looking for lighter servos but I'll see how she goes tomorrow before deciding on what to do.

[Jon H]

An unusual subject for a Laser but looks good. As for the 100, I cant build without parts. Alas its out of my hands.

[Former Member]

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[Chris Walby]

Ron,

Thanks for the weight info, I must admit I am slightly surprised it came out at 3.5kg as my BH Speed Air is 2.8kg with a Laser 70 in it (11x7) and that will do unlimited vertical so an 80 in a 3.5kg AUW model (25% different in weight and 15% in engine capacity). Not so sure you'll be able to climb out of prop hangs easily, but with the wing area and wingspan it should be a good use of your 80 and fit a 100 when one becomes available. I still think you will have a really nice model to fly.

[Ron Gray]

The fuz on its own is 2.5Kg! Not sure where I can lose a lot of weight, the servos are 56g each so even if i were to replace those I would only be saving, say, 60g (6x10g saving, maybe). Plus a smaller battery could possibly save another 100g. But that’s it, totally possible saving 160g. The mods made to the front of the fuz resulted in no weight change, what was cut out = new bits.

As said above, the intention was for it to be powered by a 100, so with an 80 I don’t think prop hanging is on the agenda but as long as it will / I can perform nice graceful slow aeros, I’ll be happy!

[Jon H]

I think you will be surprised. My Hurricane was 10lbs when i first flew it and the 80 brutally over powered it. Time and prop selection will tell!

[Chris Walby]

Jon Prop hanging a 10lb Hurricane,,,,, brutal and possibly not very scale Although a few years ago at Little Gransdon a full size Hurry put on a cracking display and the low passes blew the spit display into a cocked hat!

I don't know what the power increase between a 70 and an 80 is, but I think you are right an 80 will do just nicely.

[Former Member]

[This posting has been removed]

[Ron Gray]

Well, maiden flight carried out today but jet settings kept changing (second hand engine) so had to land (dead stick) early. When it was running ok it seemed to have a nice bit of power so maybe that move to a 100 can wait? In the little time that it was in the air I needed a few clicks of up but didn’t get chance to in flight c of g test so it could be a bit nose heavy. All other controls stayed as setup on the ground so happy with that.

Will have to get some replacement O rings for the needles - Jon? (purple carb).

[Don Fry]

Tom, cheers, my D VII prop hangs, and I've always felt guilty doing it. Laser 75, used to have a Laser 80, but I have now grown up.

[Jon H]

Depends which O ring is toast Ron. Give me a call tomorrow and we can sort it.

Chris, I was at Old Warden recently and they had their two hurricanes putting on a stunning display. Nothing fancy, no loops or anything, just swooping passes what seemed like eye level. it was certainly low. awesome stuff.

[Bob Cotsford]

If anyone is stuck for an 80, PM me