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Apr 01, 2019, 01:40 PM
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mintie's Avatar
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Build Log

frog Junior Glider


Always loved the older models and had a few Frog control line planes as a kid.

Have enlarged the Frog junior Glider and going to make it 2 channel as I miss my small slope /beach gliders.

Will build it at 40 in w/s ,

This got me going as after I watched a small sinbad glider on video on the slope

will post as build continues
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Apr 01, 2019, 04:29 PM
I like real wooden aeroplanes!
Sundancer's Avatar
I love Frog models, a 40" Junior should be a lovely little light wind slope soarer. This is not a Frog model, but a Keil Kraft contemporary and at 40 inches is the same sort of size your Junior will be, he has made a brilliant job of it. An Invader was my very first successful flying model 70 years ago and I never expected to see one flying like this!
Keil Kraft Invader. RC conversion maiden flight. (1 min 33 sec)
. I look forward to seeing your Junior.
Apr 01, 2019, 05:22 PM
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As much as I am impressed with the pivot wing, (probably the only decent way to fit RC to an invader) It was wrong in so many ways , transparent film covering , and you rolled it , it was a travesty

Sir you are a cad


I'm just jealous because my attempt to radio a KK topper only lasted half of its maiden test glide last year
Apr 02, 2019, 02:12 AM
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mintie's Avatar
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Build


Started the fuse frame work tonight . this is half hr of work . Cool video. Looks like a really nice flying slope
Apr 04, 2019, 10:04 PM
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Both fuse side frames done along with the two main bulkheads. Nose bulkhead next then can join them all together.I have put in a couple more vertical pieces into the frame as it seemed a bit to flexible
Apr 05, 2019, 12:13 AM
Slow builder
_AL_'s Avatar
Mine at 30". Great flier.
You'll love it at 40"

Al
Apr 05, 2019, 03:56 AM
Registered User
I , like SD , like Frog gliders . But I tend to stay with the one design although that little 40" Junior looks rather nice . Will have to see if I can add ribs legally . I build Princes in all sorts of sizes from 1.5 metres up to 3.5 meters , and all have competed very successfully . I have modded my 3mtr one for aero tow and am in the middle of another at the moment . I think I could build a 3m Junior quite lite , might give it a try .
Apr 05, 2019, 08:35 AM
I like real wooden aeroplanes!
Sundancer's Avatar
The 3.5 metre Prince must be a magnificent beast Geoff. How about a 4x (120 inch) version of the Fairy - this is mine, original size and F/F, I built it originally to pass on to my young nephew but his aeronautical interest has faded and he now spends all his time glued to a Gameboy and iPhone - sigh! So the Fairy has languished in the corner of the workshop for over six years and I keep wondering whether to convert it to rudder only radio. It is a really pretty shape.
Last edited by Sundancer; Apr 06, 2019 at 03:30 AM.
Apr 05, 2019, 07:35 PM
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It is SD , in the air people keep asking me to keep a steady heading across the wind so they can land on the wing and have a rest . I'll put some photos up if I get it out of the roof , it's so hard to get it all down the stairs unless I have to . The fairy looks quite nice , a straight diahedral I assume , but the Junior has quite taken my fancy , the only problem I see is the rib spacing .
Apr 05, 2019, 10:46 PM
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Will be keeping the dihedral the same as the plan but putting in a few more wing ribs. Enlarging the plan makes the spacing to great . Had to do the same on the fuse. The 30in looks and flys good going by your pics
Apr 06, 2019, 03:50 AM
Slow builder
_AL_'s Avatar
Mine has dihedral as per the plan & now that you mention it, I think I added 1 or 2 ribs each side.
I look forward to seeing yours.

Al
Apr 09, 2019, 03:53 AM
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Now we have a fuse starting to take shape. A whole 8gms. One thing I haven’t decided yet is how much wt will I save using a built up tail end compared to the light sheet.
Apr 09, 2019, 04:48 AM
I like real wooden aeroplanes!
Sundancer's Avatar
I think in the larger size built up tail surfaces may well be worthwhile. It isn't so much the weight saving as the fact that, with proper structural design, the tail surfaces can be made much more warp resistant for the same or lighter weight, albeit for more effort. Sheet surfaces, with proper anti-warp inserts are not too bad if you can find the right grade of wood mind you. Below are a couple of versions of my favourite structure for flat plate tails which I have used a lot - light and very rigid. Basically a strip (or laminated if curved) outline with sheet reinforced centre and diagonals of half the thickness, quick and easy to build and very stiff. (Also cheap as very little wood is involved!)
Apr 12, 2019, 01:40 AM
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Today’s effort Airframe near done. Nose blocks all glued together. And have a fin/rudder cut out. Airframe is at 11gms so far
Apr 19, 2019, 12:56 AM
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A bit more progress. See if it rekindles a bit more interest. Started on the wings now and have some of the frame work done on one side and a kit of parts for the other . Have added more ribs to each side and allso let the ribs into the trailing edge rather than just a butt joint. .Fuse now 21gms.


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