Build Log Drake II: electric, with ailerons

[kepa]

Hi all,

Last winter I decided I needed a waterplane for this summer. My ultimate goal will be to one day build one of Ivan Pettigrew's beautiful flying boats, but I'm not there yet. For a start, after electric-powered gliders, I thought I'd get my feet wet with a Drake II. Electric, because that's what I've been flying so far and because of the thought of calm silent summer evenings. And I'll build ailerons because I've been flying (at least) 4-channel birds since the beginning, and for the building experience.

Anyway, here's a late start for this summer. But if I can't finish the build before, say, late November, I can test fly her off the snow instead. I decided to start with the tail feathers in order to get the building going again after a while. (How common is that, by the way? Where do you start your builds?)

So, here are the central vertical stabilizer and the rudder. As you can see, I'm trying to build it light and decided to build up the surfaces instead of cutting them from sheet as the plans showed. The wood is 10x5 mm balsa and the glue used is Cascol 1809 polyurethane waterproof wood glue.

Kepa (Aki Pursiainen)

[Palmettoflyer]

Great to see another Drake II being built. I just started the same project a few weeks ago. I started with the fuse construction as it looked like it would go quickly and the enthusiasm of the build would be key on building the big sheeted side fuse straight and not looking like a banana. I have been pleasantly surprised to see the fuse coming together without any trouble. The big sheets do create some compound curves when you put the formers on but nothing very difficult to manage. I can post a pic or two of my progress if you like? I don't normally post build threads as it takes me a long time to build with a busy life schedule.

I am thinking of doing the same as you on the stabilizers and try to drop some of the weight. Also, I think the main wing is overbuilt by the plans as well. Keep up the good work.

Palmettoflyer

[kepa]

Originally Posted by Palmettoflyer

I started with the fuse construction as it looked like it would go quickly and the enthusiasm of the build would be key on building the big sheeted side fuse straight and not looking like a banana.

With me it's that as a new project is about to start, I have to first build some confidence by beginning with something simple. Then I'll proceed to more and more complex structures...

Originally Posted by Palmettoflyer

I can post a pic or two of my progress if you like?

Please do!

Originally Posted by Palmettoflyer

I don't normally post build threads as it takes me a long time to build with a busy life schedule.

Don't let that stop you! There's a guy building a(n insanely) scale DC-9 and he's been at it since year 2000 and posting along the way...
http://www.rcgroups.com/forums/showthread.php?t=208512

Originally Posted by Palmettoflyer

Also, I think the main wing is overbuilt by the plans as well.

What are you planning to do with yours? You are not building ailerons, are you? I have to fight the urge to make the wing *too* strong and heavy.

Anyway, here's my next small achievement: One of the smaller fins. I used 10x3 mm balsa for the structure, and some of the width will be sanded away.

-kepa

[Art Schmitz]

Kepa, do yourself a kindness and go with ailerons.

[kepa]

Originally Posted by Art Schmitz

Kepa, do yourself a kindness and go with ailerons.

I should have been more clear in my previous message. I'm not going to leave the ailerons out, I was just thinking about resisting the urge to "just beef it up a little here, here and here". The actual implementation is still under consideration. I think my ailerons will be more than 3/4" wide. That's the original trailing edge stock in the plan. I think I'll build something up, as I don't want the weight of (say) 2" wide semi-hard balsa trailing edge strips hanging on my wing.

I'm still building the tail parts. The last of the vertical fins is now curing. On the plans, of course, so I'll start the horizontal stab tomorrow.

-kepa

[Palmettoflyer]

Here are the pictures of my progress so far. I'm a little bit further along than the pics show. I'm about 2/3rds finished with the sheeting on top and bottom. I am still feeling good about this build so far.

I have the same idea as you about the ailerons and their sizes. I will make mine either 1.5" or 2" to so there is some aileron control at lower speeds. Looking at the plan for the wing, I think some of the ribs could be left out and only use 1/16" thickness. Might not save a lot but a little here and there!

One tip I would suggest is to cut the battery tray hole in the forward fuselage former before assembly. I cut the hole afterwards and it was a bit difficult.

[Palmettoflyer]

few more pics...

[jpgilbert]

Hi Guys,
Great to see more Drake II's being built. One of my favorites. Will be watching this thread.

Joe

[kepa]

I didn't get to devote the entire weekend for building my Drake II as I had hoped, but I managed to take a few moments here and there to almost finish building the tail feathers. Of course there's still some wood to cut and sand away... I think they are both light and still stiff enough.

-kepa

[Palmettoflyer]

Joe, Great to see you here. Your builds have been a big inspiration to me. Are you still happy with the AXI 2808/20? I have the same motor and plan to use it as well. You probably also noticed I'm using your CF rod and tube technique for the outriggers. I plan to keep the sponsons completely adjustable and removable. Any tips you can add to our work would be appreciated.

Kepa, Your tail pieces look great. I haven't decided yet if I will do exactly the same or use sheet stock. Maybe a mix of the two ideas.

My fuselage is nearly finished except I ran out of 3/32" balsa and need to buy some more before I can continue on.

Palmettoflyer

[jpgilbert]

Thanks for the kind words!

I am very pleased with the Axi 2808/20. When used with three cells and the 3 bladed prop, it gives plenty of power for this model. Hard to beat the Axi but I have used BP Hobbies motors on my two foamy Drake IIs and my new Seamaster II with great success.

I like the looks of the built up tail group. But the sheet method Ken Willard used works well also. I did reinforce the outer tail fins so they wouldn't warp. So far, so good. Many flights to date. Be nice to see how much weight it saves. My battery goes all the way forward for proper CG.

I have removed the sploats and used my wheels just a few times. Have plenty of other land based planes. Also flown without them from snow. Flys well in both cases.

Keep up the good work, guys, and will be watching for latest developments.

Joe

[Palmettoflyer]

Joe, One last question...(for now!)
How do you retain the outriggers in the tubes? I assume they are two pieces and slide in from each side. Is it just a friction fit or do you have some sort of retainer?

Thanks,

[jpgilbert]

Originally Posted by Palmettoflyer

Joe, One last question...(for now!)
How do you retain the outriggers in the tubes? I assume they are two pieces and slide in from each side. Is it just a friction fit or do you have some sort of retainer?

Thanks,

Yes, each side is separate and just slides in.

I used a small brass tab glued into the end of each spar and put a screw thru it into a small blind nut. The attached photo doesn't show it all. Hadn't drilled the hole yet. Don't have a better photo and and the plane is up where I camp during the summer.

Joe

[Palmettoflyer]

Interesting, I totaly understand. I had two thoughts. One, drill two small holes inside through the tube and CF rod. Then use a small wire to pin the CF to the aluminum tube. Other idea was to leave the CF rods long (whole length of the outrigger). Use the outrigger bars as spacers and somehow clamp the floats to the rods to hold it together. Something like a wheel collar in each float where the float attaches.

Make any sense?

Your method looks easy and simple too.

Thanks,

[jpgilbert]

Originally Posted by Palmettoflyer

Interesting, I totaly understand. I had two thoughts. One, drill two small holes inside through the tube and CF rod. Then use a small wire to pin the CF to the aluminum tube. Other idea was to leave the CF rods long (whole length of the outrigger). Use the outrigger bars as spacers and somehow clamp the floats to the rods to hold it together. Something like a wheel collar in each float where the float attaches.

Make any sense?

Your method looks easy and simple too.

Thanks,

Your first idea sounds clean and simple to me. I had tried to come up with something similar but wasn't certain if it was OK to put holes into the CF rods. I am bit more experienced now and would consider your idea. Shouldn't get any water into the hull as the rods are a nice fit for the tubes and the hole for the pins could be small and horizontal.
Joe