Build Log Thread formally known as Cyril Carr's "Supermarine Walrus," Part II, a bigger one!

[loserdave]

Think i just found my next build

[Lewis]

looks good! What is the wing span, etc. and what power are you thinking of using? Lewis

[rotorheid]

Hi Guys,

After pondering the problems of yaw on my Walrus I decided to add 4 Ailerons to try to tame the handling. The cunning part is that I hope to achieve two things.
1. Easier yaw and roll control by revresing the current control philosophy.
2. Increase the wing area and make a better wing profile.
How? I hear you say, "No problemo! Oh my amphibious brothers" I say. Lets just glue 3 of the ailerons at a rather jaunty undercambered angle and move the 4th by means of a third servo! Hmmmmm........Pylon racers manage with one.
My thinking is this, Power at take off and climb gives me a massive right yaw/roll effect, countered ony with my rudder, even more effective in the propwash.
On powering down for approach and landings it all reverses direction to the left, with slow response due to less propwash, a trim and finger nightmare.
I have moved the motor thrust line as far as it can go sideways, both left and right with only a marginal improvement, so no joy there.
If I go with left hand on rudder (power trim management) and deep routed primary learning right hand for roll I think I should be good to go. What do you think?? Cheers mates,
regards to all, Al

[rotorheid]

Hi Guys,
It is quite windy but I had to test fly the new config on the Walrus, a definite improvement. (Why don't I just build to the plan, that one flys great!)
So no more fiddling untill flown in calmer conditions, slow but sure progress I think.
regards to all, Al

[rotorheid]

Hi Guys,

I have decided on my next shiny flyingboat project, sometime in the near future, a Supermarine Stranraer, (pronounced stran-raahr)
The name is generally believed to come from the Scottish Gaelic "An t-Sròn Reamhar" meaning literally "The Fat Nose."
I am looking at drawings, trawlled from the 'net, something around 1.5 mtr wing span. I will do a build log at that time to keep you informed of progress, meanwhile some pics to show what I'm havering about.
regards to all,Al
eps. Basic calculations: Wingspan 1517mm/59.7", Chord 166.5mm/6.55", Area 5.27 sg ft. Mass 1.5kg/53 oz. Loading 10oz sq ft. LOA 945.3mm/37.2"
A bit chunkier than my Widgeon.

[Lewis]

Hi Guys. Well I'm making progress on my puddle twin, mostly on the fuse; i.e push rods and servo installation. I got the tail feathers finished last night and I will hopefully start onm the wing this week. More to come. Lewis.

[meatbomber]

Hey AL!
Look what the Derpon fairy brought !!

too bad that the B2 parts don`t fit... i`ll have to make that differently, then i`ll put teh side panels on after hiding the wire runs inside the fuse.

[rotorheid]

Hey MB!

OOh! Looking good, she is such a neat builder too, I hope you looking after her. Yes some of the bits are a bit iffy, you have to go your own way sometimes. Are you making the undercambered wings? regards to all, Al

[meatbomber]

yup i inted to build it exactly after the plans... thou i want to make mine float i`ll try to:

"build it right, straight and true, make the bugger watertight"
and if i start out light it should be easier to keep weight under control (i like my planes to be floates)
And i really like the littel details, the folding wing, and the manual retracts i hope i can get that all to work

[rotorheid]

Hi MB,
Good on you mate, I'm sure she will fly good for you. I had my Stranny hull outside in the sunshine to make the filler go off faster, 5 mins later I went out to get her and I heard..pssssssssssssssssss! What the heck, is that a big bug in my spare tyre pile, have I got a puncture? Aye, in the hull! The air inside had expanded and was blowing out of a pin hole in the deck That's the trouble with the heat here, you have to be carefull or you get an Inflataphibian! cheers,
regards to all, Al

[meatbomber]

Got a bit more done...

Teh fuse goes together pretty good... i took 1mm depron for the lower planking as it bends a lot easier and is easier to make it fit. Hope it will standup to the abuse on teh water, but with WBPU and Tissue it should be plenty stiff..

[rotorheid]

Hi Guys/Girls,

Moved the motor angle more over to the right to stop the right yaw on take off and landing, now directed at RH tailplane. It was too much of a trim change to cope with comfortably, will test fly as soon as possible, man this fleet maintenance and mod program keeps you busy! cheers,
regards to all, Al

[rotorheid]

Hi Guys/Girls,

Just some more info on the Walrus yaw problem, it's managable now by the last correction. Gave her a quick wizz around the sports pitch before tea, pool was full of swimmers, what cheek! The pics show the arrangement, very simmilar to the original.
The Cyrill Carr drawing is very good, but I didn't have the same power set up, my motor kv was different so prop different, etc etc etc. The worst point on my side was the 50% overweight! so I guess I was lucky that I didn't total her in all the flying, however, it's onwards and upwards and we have to make sacrifices sometimes, it's the Walrus who is giving up her motor for one side of the Canadair CL-415, to film the Highlands and islands of my homeland. Should make a nice change from all the blue skies and sun here in the very hot sandy place. But that's another story, for the future.
I would recommend building the Cyrill Carr Walrus as he drew it, lighter is better, perhaps an even larger version of 36-38" span would be nicer than mine too?
Cheers, regards to all, Al

[brennanj2]

Al,

Thanks for the update.

John

[SpinningInPres]

FREAKING AWESOME build!

Thanks for sharing all your tips. I especially like the food wrap hatch seal!

How do you keep the hatch down? Magnets?

PS