RE: Cold Duck - Build
 

I had to send in my “rocket ship waver” application to the AMA so the Tiporare can be flown. Expect to receive the waver any day now, then we should be all systems go.

RE: Cold Duck - Build
 

I've never heard of that.:D
How fast does it go?
Should I have gotten a waver last time I flew my Laser Arrow at 200+mph?:D:D

RE: Cold Duck - Build
 

View of the fuselage with the sides glued to the top. I shaped the triangle corners on the tail section by test fitting the sides to the top and then glued the two sides together at the tail first. After the glue on the tail was set I took it apart and put epoxy on the firewall sides and the second former and Titebond on the third former. Titebond was put on the top edges and triangles on the fuselage sides and the sides reassembled on the top and taped. I placed the fuselage on the workbench upside down and put weights on it to hold it together. The scribed line on the underside of the top was used to make sure the tail point of the fuselage was centered.

View of the progress with the fuselage parts sitting on the wing cores. The nose blocks and nose ring are not installed yet. A lot of razor plane work will be done to make the top of the fuselage very rounded and flow into the rounded nose section and 2” spinner.

RE: Cold Duck - Build
 

It doesn't look like this plane is going to take 14 years to build.:D

RE: Cold Duck - Build
 

Very nice craftsmanship on the plane. Parts almost look laser cut. How does your wife let you get away with always photographing your models at the top stairs?

RE: Cold Duck - Build
 

Thanks for the positive input and I’m having a lot of fun with this build.

My RC workshop is in a very large unfinished walk in closet/bathroom (supplied with HVAC) that is located next to our second floor loft area, so my shop is too small for photos. The photo is on the entrance to the bridge that ties the loft to the other side of the second floor and stairs (very southern). If everything is clean then it’s OK to drag it out to the loft to take photos and get a feel for how the overall progress looks.

RE: Cold Duck - Build
 

View with the nose blocks and nose ring installed and some of the fuselage shaping completed. The lower ¼” balsa part of the back fuselage is just taped on and I’ll glue it on after I work out the push rod routing. The fuselage weight at this point is about 9.5oz. Super light!! I need to resin the engine and fuel tank area for fuel protection so that will add a little weight. It would be pretty neat if this baby came in round 5.5lbs. You can never be too light or too fast!!! The original was pretty fast with the old Veco 61 at 6lbs, imagine 5.5lbs with a hot 61.

The wing is missing the 1 ½ wide aileron stock so it looks a little skinny in the photos. The symmetrical airfoil on the Cold Duck is an 18% - 15% taper. No need to create a lot of drag with a fat airfoil.

The Webra 61 has been temporally installed as a jig to setup the nose ring position. Getting the 1/16 ply wood nose ring positioned correctly was a pain but eventually I got it right on the mark.

I’m not happy with the looks of the Great Planes canopy. It is too short and narrow, so I’m going to investigate the Wing canopy recommended by Paternguy .

RE: Cold Duck - Build
 

View with the ailerons taped on.

RE: Cold Duck - Build
 

Lookin good.:D

RE: Cold Duck - Build
 

You could always go with the Wing MFg ck 604 (Dirty Birdy) Canopy. LOL

Might look pretty sharp on this bird.

RE: Cold Duck - Build
 

The engine opening has been ruff cut and will be cut to the exact shape latter. The small area behind the nose ring is too complex to fill completely with balsa so I filled the area with a small amount of mirco-balloons mixed with epoxy. You can see the cuts in the triangle corners pieces to allow them to easily bend to the shape of the nose.

The inside of the nose area and fuel tank area was fuel proofed with epoxy thinned with alcohol. The bottom piece below the tank was fuel proofed before gluing it to the fuselage. I added a few triangles behind the firewall to strengthen the mounting.

RE: Cold Duck - Build
 

I think its very cool that somebody else is a fan of the Cold Duck my father scaled that plan to take a 40 fsr in the early seventies and then in the early eighties he rescaled the plans to suit 25 size engines. I have the original prototype of it that my father built as a construction and plan article for the magazine he published, what father did was to simplify some areas of the model yet keep all the basic charm of the original scaled down to a 25 size sports model, the one I have is powered by a 25 year old OS 25 fsr and it is still a great fun aicraft to chuck around even today.The so called Mini Duck keeps nagging at me to biuld an even smaller one for electric power,perahps one day I'll get around to that as a project.
regards
Alexis

RE: Cold Duck - Build
 

Alexis,

I’m a big fan too but I have a little biased connection with the Cold Duck. Interesting about your father rescaling it to a smaller size and I’ve met other people that have built it from the RCM plans as well. Apparently the original RCM article made it all the way down to Australia! It would be great if you could post a photo of his article and your current Mini Duck on this thread.

Some images of the original June 1971 RCM article are below.

RE: Cold Duck - Build
 

The lower front of the fuselage has been glued on and shaped. Epoxy was used at the bottom of the firewall and along the bottom of the second former.

More work was accomplished with the razor plane and the characteristic curvy flowing lines of the Cold Duck are starting to show. It’s pretty cool to see it coming alive again after all these years. At this point the weight of the fuselage is 9.25oz without the lower back balsa sheet installed.

The sanding of the fuselage will be the next step and then I’ll start work on the wing.

RE: Cold Duck - Build
 

The four wing skins are glued and cut to rough shape. Three 4”X1/16” sheets are butt joined using Titebond glue to form the wing skin. Like the original the cores are cut to wrap the skin around the leading edge, but I’ll be sanding 3/16" off the front wing edge so I can use a ¼” balsa cap on the front edge of the wing.

The process of building this aircraft from plans is so easy!

RE: Cold Duck - Build
 

More work on the wings was completed. I sanded 3/16” off the leading edge of both wings using a 1.5’ long board that has sand paper glued to it. Dave Brown Southern Sorghum contact cement was used to glue the wing sheeting to the foam core. The Sorghum is pretty light when it dries and does a great job of holding the balsa to the foam. Brushed out well, It took a little over 4 fluid ounces to glue both wings.

View of the sheeted wings with the aileron stock.

RE: Cold Duck - Build
 

Looks good.:D

RE: Cold Duck - Build
 

Sorry, things have been moving along so quickly I missed getting an image of the wing leading edge installation. The image below shows the ¼” balsa edge installed and shaped.

The wing was measured and marked for the landing gear blocks. Can’t believe I’m not installing retracts in this beast! The wing balsa was cut away and a hot wire was used to cut out the foam. An aluminum tube was used to cut out the space for the gear block dowel and then epoxy used to glue the blocks in place. The top of the gear block is flush with the wing surface and is glued to the edge of the wing skin and the foam core. Masking tape was used around the cutout to keep the epoxy off the wing skin surface.

RE: Cold Duck - Build
 

The Duck has wheels! Images of it sitting on its wheels to see how it looks. At this point it weighs 4.5 lbs with engine and radio gear.

RE: Cold Duck - Build
 

Image with the ailerons and wing tip blocks roughly shaped. This shows a better view of the wing platform.

RE: Cold Duck - Build
 

It's starting to look more like a Cold duck every day.:D

RE: Cold Duck - Build
 

Thanks woops! The trike gear is growing on me. I finally remembered where the 18 – 15 percent wing concept came from, the Tiger Tail. It’s not the same wing platform but it does share the same airfoil percentages.

The thought that it could weigh less than 6 lbs and be powered by a modern hot 61 2S has me really looking forward to its first flight.

RE: Cold Duck - Build
 

You have quite a stable there. A Cold Duck, Kwik Fly III, and a Tiporare. Any more that I missed?

RE: Cold Duck - Build
 

Do you ever actually fly these birds ? LOLOLOL

RE: Cold Duck - Build
 

LOL:D