Wid's kit 902 Bird Dog

[Angie332]

Brandi got bored with her model. It looks like I will be putting it together. LoL I will see if Ican find a 900 sseries. Probably have to oder it.

[davidchoate]

I Got the Birddog. I'm either doing that next ,or the Aeronce. IM gonna flip a coin over it.

[WIDDOG]

Guillow's does sell some supplies for the Scratch Builder. I would like to see them addl more items. In this Peanut scratch build I am using Guillow's 3/4 inch plastic wheels.

[Angie332]

That's looking neat. I bet she will fly high in the clouds

[davidchoate]

Let us know the final weight. I'm obsessed with light building now on FF stuff.

[WIDDOG]

I have a AUW (All Up Weight) of 17.5 g. Also have some trim flight video. I have a hard time figuring rubber thickness, rubber length and prop size combinations. I'll keep trimming till I get it though.

http://youtu.be/6hjVbFzrubE

[davidchoate]

Not too bad. Thought you were gonna be climbing a tree for a minute though. Came close .

[David Lewis]

When attaching the wing to the side of the fuse, the trick is to add joiners that are the same hardness as, and with the grain running perpendicular to, the fuse side and the root rib. I extend the end of the crosspiece near the wing LE out past the cabin side, and add a 3/32" square joiner near the wing TE. This precisely keys the wings into the fuse with equal incidence.

When you glue two pieces of wood together with the grain parallel, the joint is heavy and weak. Basically the wood peels away when you put any force on it. Cross grain joints are stronger.

Secondly, using a birch dowel for a joiner doesn't work well. A dowel is stiff and unyielding, so most of the loads get funnelled into the dowel, and these concentrated loads are transmitted into the soft balsa. Balsa joiners distribute the stress more evenly.

[WIDDOG]

Thanks for the input David,

I got sidetracked form the 900's series kits. I want to try and fly a display only Guillow's F 14 Tomcat. Since they stopped making Rapier Motors this has become even more of a challenge. I managed to rule out a couple of things. I am convinced now that electric would be my best source of power. I look forward to trying another 900 Series kit soon. I have another Thread called Free Flight Jet Models.

[davidchoate]

David, any chance you could post a photo of youre wing joining method ?

[David Lewis]

The crosspiece sticks out past the side of the cabin (A). Then there is a short piece of 3/32" square that also joins the wing to the fuse (B).

[davidchoate]

Thanks for the diagram. I have been using dowels, but I see how youre method has certain advantages. Thank you again.Thats how I did My Edge wings, and it turned out well, but the design was halfway there, so I didnt really invent it., but i understand it. Its a bit Xtra effort, but worth it.

[davidchoate]

Widdog, I went to view youre trim video, but it said "Private ", so I couldnt. Being ready to Fly my Bird dog I very much wanted to see it. Oh, well. Wish me luck .

[WIDDOG]

Sorry I remove my less than stellar vidoes from Youtube. Anyway I was experimenting with Guillow's propellers on that particular video. My results seem to indicate that the Bird Dog does best on a 6 inch Peck Polymer propeller. However, If you are using a Guillow's propeller the Guillow's D6 propeller works much better than the D5 propeller that comes with the kit. BTW David if you don't have a 6 inch Peck Polymer propeller message me.

Your Bird Dog looks fantastic. Great job with your Build/Thread.

[WIDDOG]

I have a brand new kit 902 Bird Dog on order from Guillow's. I decided to bring back this old post and post my new kit 902 build on it. I have to admit that in the past I did a lot of experimenting. Anyway no experimenting on this new kit 902 build. I will mod the propeller and noseblock to allow Stretch Winding. I don't really have a main point for my build other than to keep the big post board moving.