Inspired by Sundancer's build log and enthusiasm for Frog designs I decided to join in the fun of his proposed Frog build-off.

I'm no photographer and just a one finger typist so don't expect anything like George's standard of posts.

Looking at the Frog website my choice was between two little models in the Junior series - Scamp & Speedy. These are essentially the same design with the exception of the wing position. Scamp mid and Speedy low.

The safer option would have been the Scamp so naturally I chose the Speedy

I downloaded the plan and, using the Tileprint program, scaled it up to 3.5 times the original and printed it out. The scale factor was chosen to make best use of standard 36" sheets and results in a span of 40".

Using Profili I chose a Goe 436 - a simple 11% flat bottomed section - and printed out the patterns for the various chord lengths of the elliptical wing.

Next step is to make a kit of parts and collect together the necessary hardware.

Ray

Subscribed!
sparks

Go for it Ray!

Looking forward to it Ray!

Jon

Thanks for the encouragement guys

Having cut out most of the parts for the complete model I made a start on the tail surfaces. Since the original was of all sheet construction the enlarged version will have no open structure so these are just cut from 1/8" light quarter grain sheet.

Don't believe anyone who says a tailplane can be made from any old wood as there is little stress on it. Ever since the day I folded a tailplane flying a slope soarer I have used a spar of some description. That's the dark strip at about 1/3 chord and the fin/fuselage key on the fin.

The elevator horn is internal and the hinges 1/4" wide strips of hairy mylar superglued in. Total weight of the parts shown is 1oz.

Ray

Very neat work Ray.
Where does one get hold of 'hairy mylar'?
sparks

Sparks,

I use these chaps. Not really hairy I suppose but just mylar with rough paper on each side as used on nearly all ARTFs

They are supplied 1"X3/4" so I cut them into three 1"X 1/4" strips. Punch a couple of holes for the superglue to flow into, angle off each corner to aid insertion (pardon ) and put a pencil mark at half way to show where the hinge line will be. One drop of thin Zap on each side and I guaranttee they will never pull out.

Ray

Thanks for the info. Ray
sparks

Next component to be built is the wing. I had considered 1/32" balsa covered foam made as per Rob Millinship's Spitfire wing which I built years ago but I didn't have enough suitable balsa for skinning so it has to be ribs and spars.

The skins are 1/16", ribs 3/32", false leading edge 1/8" and the full depth spar 1/8" with a 1/32" ply dihedral brace. The two curved and tapered strips tacked to the board are the wash out jigs positioned under the trailing edge when adding the top skins.

Edge joining the covering sheet is done with good old balsa cement, cyano for everything else plus epoxy used for the trailing edge join to stiffen it. The leading edge is two strips of 1/8" and the tips soft 1/2". Total weight is 3.8 ozs.

Ray

Wow Ray, you are not hanging about. It's a lovely wing shape. I shall have to hustle or you will be finished before the Zephyr.

Very nice work. The sheeted wing really keeps the Speedy feel...

Nice work Ray!
sparks

you are not hanging about

Well, like you George I am recently retired, the wife's away visiting friends for a week and the weather is terrible so what else should I be doing

By the way I forgot to mention that the Speedy will be a one piece model hence the big gap between the wing panels. The fuselage will have a slot for the spar and the wing will slide in from below and be glued to the fuselage sides.

Finally, would anyone happen to know what colour the printed balsa scheme was on the original FROG kit (red?)

Ray

I did build one fifty-odd years ago Ray and I THINK it was red, or maybe orange, but I couldn't swear to it after all this time as I did build most of them.

On the House of Frog site almost all of the offerings seem to be red or blue so I bet the Speedy would have been one of them? Or use the box art picture for inspiration!

Gordon