Scratch Build "Turbo Crack Beaver"

[Derek]

Ok Cameron...the time has come. I said that I'd like to build this plane and I meant it, lol. I have all the needed electronics and the foam board that I'm going to use. All that I need to do is draw up the plane parts and build it. This first post may jump around a bit, so please bear with me. Can you get me some measurements?

I've looked at some pics of the plane and it looks like the vertical stabilizer is an entirely separate piece from the fuselage and is added during the build. What is the length and height of the vertical stab? Then, the horizontal stab. What is the length and width of that?

It looks like the fuselage is actually made from two pieces of material that are put together to form an "X" (if you look at it from the front or rear). How long is the actual fuselage, not including the vertical stab?

What's the length and width of the main wing. What's the length and width of the ailerons, elevator flap, and rudder flap?

How long do the landing gear legs hang down from the fuselage?

How far back, from the nose, is the leading edge of the main wing?

Cameron, if you can get me these measurements, I'm pretty confident that I can build, and document, a pretty good comparison.

Thanks buddy!

[DamhDearg]

Ill get that for you before the weekend Derek. Be cool to try this myself in the winter using depron.

[Derek]

Ill get that for you before the weekend Derek. Be cool to try this myself in the winter using depron.

No rush, Cameron! I'll be working all this weekend so you have plenty of time to get me some measurements. I'm very much looking forward to the build. I think it will be a fun flyer to have around. As for using depron, it will definitely work...just be sure to add a bit of carbon fiber (or similar) for reinforcement.

[DamhDearg]

Here you go Derek.

Vert Stab - top 1 1/2 ", bottom 3". Extra 6 1/2 " on bottom of stab to attach to the fuse. (Does not include rudder surface)

Horizontal Stab -W 2" L 8" (Elevator surface not included)

Fuse -L 26"

Wing - L 34 1/2". W 6 1/2" (Includes Aileron surface)

Ail - L 14". W 3"

Ele - L 8". W 3 1/2"

Rudder - L 8 1/4". Width in middle 3", width at top - 4 ", width at bottom - 6". Atached to a 7 1/2" long separate piece which is glue to fuse and bottom of rudder

Landing gear - 3 1/2"

Leading edge of wing from nose - 7"

Hope that helps

[Derek]

That very cool, Cameron! Thanks for that! I'll try to get started on it today.

[Derek]

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This in an image that I Google'd. According to your measurements, measurement "A" is 3.5". Fair enough. Can you tell me what measurement "B" is?

[Derek]

Hey Cameron...I've started the build...pics of progress to come.

I've been looking at a lot of picsof the plane and I've got some questions aboutyour measurements. Listed above, you say that the wing is 34.5"x6.5" including the ailerons. You say that the horizontal stab is 8"x2" and the elevator is 8"x3.5". Can you double check this for me? The elevator just seems small in comparison to the wingspan.

If these measurements are correct, then I'll move forward. Those measurements would give 4" elevator halves. This may be correct Im Im just over thinking it...like that ever happens lol.

[Derek]

Well, I was looking at a bunch of Google'd pics of the Crack Beaver and, with some deductive reasoning, I came to the conclusion that the length of the horizontal stab, with elevators halves, was in fact 16". So, that's what I cut out. I got each piece drawn out, with some imagination, covered each piece with clear packing tape, cut out each piece and began a bunch of dry fitting. My build surely won't be totally perfect to a "Crack Beaver" but the general idea will be there. As it sits right now, I have each piece glued into place and we now have a new plane on the work bench. It is ready for a bit of color, to be determined later. Once a bit of color is added, the electronics can be installed. Probably this weekend. Here are some pics

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[pvolcko]

Wow. Tail authority much?

[DamhDearg]

Impressive Derek. Just checked the horizontal stab. It is 14 " with the elevator halves.

[Derek]

Wow. Tail authority much?

Yeah, lol...there's a lot of tail authority. I've never seen this plane, up close, so I'm just kinda going off the measurements that Cameron gave me, some Google'd pics, and a bit of imagination.

Impressive Derek. Just checked the horizontal stab. It is 14 " with the elevator halves.

Thanks Cameron! I made the elevator 16" but if yours is 14", I can cut mine down a bit and that will help save some tail weight and still have plenty of tail authority, as Paul has mentioned, lol.

I have some wire that I can use for landing gear. I have the wheels and all the electronics. I'm working tonight and tomorrow night but I should be able to work on the plane again this weekend.

[Tony]

Looks good D. Yet another plane eh... Do you ever rest mate... Haha

[Derek]

Looks good D. Yet another plane eh... Do you ever rest mate... Haha

Thanks Tony! Do i ever rest? Not a chance lol. Im always working on something.

[Tony]

I know... Lol...

[Derek]

I don't have any pics right now but I have the elevator and rudder servos installed with pull/pull linkages. I have the AR400 rx bound to my DX8 and I have the main wing cut out. I'll cut the ailerons tomorrow and add aileron servos. Then, I'll just need to mount the motor, secure the esc, and mount the main wing. I'm still not sure how I'm going mount the main wing yet. According to the manual for the "actual" Crack Beaver, the wing is simply glued to the fuselage. I'm not sure that procedure will work all that well with my foamboard. Once I can get the wing added to the fuselage, I can use the battery to locate the CG and this plane will be ready for maiden.

Cameron...are there any specific questions that you have, as far as setup or whatever? I remember you saying that you would probably have some questions. I did download the manual for the "actual" Crack Beaver and I will set my control throws very similar to the recommended specs. I just hope that my 3 years old 1500kv motor is up to the task, lol.

[Derek]

I've got the ailerons cut into the main wing. It looks pretty good. The aileron servos and linkages are installed. I plugged everything into the rx and all control surfaces are working properly. Then I flipped the flaps switch and nothing happened. That's odd! Actually it's not odd at all you bonehead! Flaps aren't accessible with a 4 channel rx (what an idiot, lol). So...I've raided a 6 channel rx from another plane and I'll get the flaps and all programmed on my next day off.

I still have to mount the motor, secure the esc, ziptie some servo wires, and then add the main wing. Not real sure how I'm going to secure the main wing. The manual for the Turbo Crack Beaver shows that they glued the wing to the fuselage. Well, the material they use is EPP foam. That's probably real easy to glue. I'm using foamboard that has been covered with packing tape. Maybe I can just cut back some of the packing tape and paper on the fuselage and wing area so that the glue has something to bond to. I'll get it sorted.

[KevG]

We need Pics, lol

[Derek]

I'll go take a few pics right now

[KevG]

[Derek]

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I just have the wing sitting on the fuselage but the plane is really coming along nicely. Those 3" ailerons are massive lol