A custom SIG Skyray

What's the story with the non-standard wing David?  Looks like you traced it from something other than the Skyray.
Also, I'm a little concerned about the use of packing behind the tank mount.  An "old backpacking mattress" sounds like foam to me.  I'd say you're in danger of breaking the mounting lugs off of the tank.  Another solution to the balance issue could be use of an 8cc tank rather than the 5cc one fitted.  Then, an easier solution still would be to get a heavy hub, but that nice red PT spinner has to go. https://coxengines.ca/cox-.049-hub-nut-balancing-weight.html  They have yellow plastic spinners to suit.

Rod.

Look Great David !! I like the colors and Boop Too , hope you have some FUN with her !

Thanks getback .

Oldenginerod, that sounds like a valid comment about breaking the mounts off the tank. I have a couple of spare tanks, but don't like to lose them. Maybe it is better to mount the engine entirely with rubber or not at all. Maybe I will change to a rigid spacer. I don't want to start with a long flight, so a bigger tank is not ideal. I prefer to lengthen the mount to adding weight because nose weight effects the total weight of the model. I am fond of those rubber spinners, because the first time my son flew one, I forgot to step back and it hit me in the knee. It would have hurt for more than a minute without the spinner.

RknRusty, It looks to me like there is a weak point between the engine support blocks and the wing, so I added a bit of carbon there. I think I will paint blue over the silver, trying to leave some metallic look. My order from SIG with blue in it came today.

Pretty sturdy landing gear you've got there.

The wing is just whittled out the way I want it. It is planed thinner near the rear edge. It used the full span and chord of the the piece, disregarding the printed outline. It is nearly elliptical for reduced induced drag, though that may not matter much with a nearly flat foil.
It is swept forward to reduce cross wind sensitivity, like the anhedral of the Wright Flyer. In a cross wind, the up wind wing has less airspeed perpendicular to its length and therefore less lift, tending to make the airplane pull up wind, keeping the lines tight. The left wing is longer than the right to carry the weight of the lines, sort of like in a speed model.

Dave, I like that, you're a calculating guy. You'd fit right in with us Stunt nuts.
Rusty

"Custom is right"!! I like the landing-gear Dave! It looks pretty "stout". I've soldered-up support-struts like that.. and never had a problem with my wire-gear bending from a hard landing. It adds some weight to the model.. but it's sturdy. I always "cringed" when having to straighten a bent-back single-wire strut due to a hard-landing.. afraid of stressing the gear-straps.. or the fuse.

I see that your running a muffler too.. I hope that she fly's well for you. Is your "niece" living nearby to witness the maiden of her model?

Betty Boop is truly the icing on the cake!

That silver wing and red fuselage gives a hint of a profile TD-1...

The Obsessed Mark

I flew it!
I thought I could fly at the Department of Motor Vehicles parking lot, but at 7: AM on Saturday someone was putting down rubber triangles.
So I went to a parking lot in the Lockheed Sunnyvale complex that I had spotted on Google Earth View. It has no trees or little barriers, just lines to mark the spaces, and appears to be little used. It is at D and 5th streets, next to the Aspiration Dome. A bit hard to find because the small streets are not marked. It lacks only grass.
I only flew it once, very rich. It sort of floated around with enough line tension for control. The Cox reedy started right up, after being idle for the last ten of its 40 year life. It bounced on landing but stayed right side up.

HURRAY

for the flight of your SkyRay!

Very nice to hear of  your suscessfull flight.  

I can relate sort of

In my case the best flying site is out sports complex with several ball diamonds and soccer fields

in the complex is a latrine and kiddo play ground ( jungle Jim stuff)

Today as I was setting up, too many soccer mom's brought kids to enjoy the early morning cool air

I am glad you got to fly the Skyray

At least one of us got to fly a bit...great report

David Ingham wrote:I flew it!
I thought I could fly at the Department of Motor Vehicles parking lot, but at 7: AM on Saturday someone was putting down rubber triangles.
So I went to a parking lot in the Lockheed Sunnyvale complex that I had spotted on Google Earth View.  It has no trees or little barriers, just lines to mark the spaces, and appears to be little used.  It is at D and 5th streets, next to the Aspiration Dome.  A bit hard to find because the small streets are not marked.  It lacks only grass.
I only flew it once, very rich.  It sort of floated around with enough line tension for control.  The Cox reedy started right up, after being idle for the last ten of its 40 year life.  It bounced on landing but stayed right side up.

Good on you David! Very happy that you had a good experience! Did you use your "stooge"? I'd like to see a photo of it. I use one too.. but need to make a new one for use on pavement. How did it feel with the elliptical-shaped wing.. and offset panels? I thought that was a neat experiment to try.

I've never gotten a successful flight in over asphalt.. but my time is coming. My 2014 CEF speed-contest model experienced repeated nose-overs on launch, due to its small wheels.. and the "tail-high" position of my stooge while on my only attempt at flying over hard-pavement.



The gear on my airplane in the above photo is "stubby" and wing-mounted.. which didn't help matters. Add to that; a tail-gear/wheel sitting atop a 1/2" plywood stooge-base.. and you have a recipe for nose-over launches.

I'm glad that your engine was quick-starting David! That's always a plus!!!!!

My stooge is extremely primitive but works fine. It consists of a coil of stiff wire attached to my flight box, a loop of doped string attached to the tail with thread and a tapered stick on the end of a kite string. The stick goes through the coil and through the loop at the center of the coil and pushes in till it jams slightly on the coil. I pull on the string with my left hand, the stick comes out and the airplane is free.
When I take off from anything but pavement, I use an unfolded paste board box as an air strip. With 6/3 propellers, my airplanes are airborne by the end of the strip. That probably wouldn't have worked with it set as rich as it was today, so I would have had to lean it out if I didn't have a smooth surface to take off from.

"I heard the news today", way to go David!
Was happy to read of your successful flight.
Bob

Here is the stooge.

Way to go David !! Good to hear you go some air time even=if it was a slow flight , Success is what counts !! Pray tell us a little more , how it felt having a handle in hand after a huge layoff ??

I felt somewhat tired and dizzy, even though I have been practicing with a little line powered CL toy with very short lines. And of course happy that I was able to get a flight.
I am unsure how long that field can be used. A guard might come and shoe me out next time I fly, or I might be able to fly there until a building is built there. It will be louder when leaned out, and I have the Wen-Mac with no muffler and TD powered ones. The place with people near is the Juniper Aspiration Dome, and I didn't see cars there at that time, so I am hoping for the best.

I noticed that my trainer engine has a fuel tank that is not for inverted flight, so I put my old stunt reedy in my flight box.




This engine has appeared on Wikipedia, and I find it in image searches.

I flew it four times this morning at the California Department of Motor Vehicles Industry Service Center, in Mountain View, at Showers and Latham, in the parking and truck maneuvering lot. The other two times I tried there, people were driving trucks there, but this time there was no one else.  The uninterrupted space is just big enough for reasonable safety with the 30 foot lines.  The only people near early weekends are the motor home squatters parked on Latham, and they must be used to trucks practicing at such hours.
I am not able to land it well, maybe because the up control is still very limited, and it bounces a lot.  The landing gear have not needed to be straightened, but once when the motor stopped when it was high I broke the propeller.  (I did have it turned so it would stop horizontal.) Some of these propellers lose strength and flexibility with age.  I am running it at full power now.  Afterward, I moved the lines to the outer holes of the handle.  The next thing may be to take out the spacer to move the center of mass back a bit.  I notice that my similar Carl Goldberg Stuntman has the CG farther back.

I am thinking about what I would have to do to get back to where I was when I flew with the Stunt club in the 1970s.  After re-learning some stunts with this one, I could fly my heavily patched Stunt Man, which now has a TD engine.  Then I would be ready to try my Baby Flight Streak.  In addition to the built up symmetrical wing of the kit, it has "combat flaps", enlarged elevator, to compensate for the center of lift transfer of the flaps, and a TD modified for constant flight speed.  The leader of the stunt club learned for me that the way to prepare a TD for stunt is to use a Black Widow cylinder.  At that time Black Widows had no sub piston induction.  The TD having a real venturi carburetor, gets richer as the speed increases, without subinduction to keep it lean.  That slows it down when the model is flying downward, much like the larger engines designed for stunt that the other club members flew.

David , good to hear your getting some fly time in and not getting run off , so you're leaning it out for some faster action now!! Its good working up to the Skyray . I was going to ask , did you do the write up on that engine with the case shaved ? That's interesting about changing the TD cly to Blk Widow for a more steady run for stunt / Those TD's can sure enough take you for a ride ! The fleet is looking good there can tell they have been flown

I actually flew from a sanctioned field.  Across the Bay in Alameda, a tiny model airplane park.
It is much better with the controls set more sensitive and the spacer removed.  It is still tame, about my speed.  The engine is merely a Babe Bee with an old type cylinder that I selected for having no sub piston induction, to go with the muffler.  It now does good landings, except that it turned over on the grass.  It climbs nicely, but I haven't attempted a loop or wingover.
After driving 40 miles, it wouldn't start, until I took the head off and dripped fuel on the piston.  The problem turned out to be that I had turned the muffler so that the opening was not over an exhaust port.  Dripping fuel on the cylinder wall didn't seem to prime it right.  I had some problems with my makeshift stooge, but another modeler was there to hold the tail.
[Another nice thing today was that my car got about 80 miles per gallon, and the cumulative miles per gallon now reads two tenths more than when I bought it.]

Nice planes and Congrats for the successful flights!

But... 80 Mpg! That's better than the Babe Bee on your plane

What are you driving?

Gas around here costs about 1.45€ per litre that's like $6 and change per gallon  So I am interested