C-17 Globemaster III - 50mm EDF

[Mid7night]

EDIT 2/18/17: PLANS! View attachment M7_C-17_R1_PLANS.zip

This is my special Flite Fest West build; the C-17 Globemaster III! This plane is especially close to me; my father lead the structural test program on the real thing, so I basically was raised on this aircraft. I recently got a battery that turned out to be way to big for its purpose, so I got to thinking "what else could I use it for?" Hence...C-17!

I've been working on the plans for this for a while now, but been waiting to post about it until I actually got started. Tonight I finally plotted them and starting cutting paper.

It's a little rough, but one of my personal side-missions was to make the plans something that other people could build from as well, without too many 'advanced' foamboard techniques. That's why the fuse is largely octagonal. I'd like to know people's opinion on this; do you think it's too simplified? Would you rather see it more rounded, if it meant a harder more involved build?

I'll be powering it with 4 FMS 50mm EDF's from Banggood: http://www.banggood.com/FMS-50mm-12...0-KV5400-3S-4S-Brushless-Motor-p-1115809.html
which they were kind enough to send me for test and review.

At any rate, I'll be starting here. Follow along if you like!

CAD mockup:


Plans:


Here we go!

 

[Crazy Goats]

Fantastic! I love this plane so much. The first time I saw one was at an airshow, and I have loved it since. I can't wait to see the finished product!

 

[T-Richard]

cool project

 

[Michael9865]

Awesome! Subscribed

 

[rockyboy]

Very cool project! I like that you're tackling this with an octagonal fuse as it's not something I've seen as often here in the forums. And I really like seeing variety in model design and techniques.

Are you planning to stick with the air force gray scheme, or one of the more rare ones. I think the Indian Air Force green scheme looks pretty nice, and unusual on this model.

 

[Mid7night]

Very cool project! I like that you're tackling this with an octagonal fuse as it's not something I've seen as often here in the forums. And I really like seeing variety in model design and techniques.

Are you planning to stick with the air force gray scheme, or one of the more rare ones. I think the Indian Air Force green scheme looks pretty nice, and unusual on this model.

Thanks! I started out with a much more round design that involved many more 'sectors' for the nose and tail sections. It was doable, but not easily repeatable. It also had some other features that were making the whole thing too heavy, so I tried paring it down. The octagon shape lends itself to being close-enough to round from the air that I think it'll still look good, and yet not too many pieces or steps in construction. It also makes mounting the gear fairings (and wings) a bit simpler.

I'll be sticking with USAF gray ... primer is cheap, and I loathe masking.

 

[Aviator08]

Very cool! Following.

Here is one I built a couple years ago. I didn't have the motors for it ,so it is a static model. I gave it to a co=worker whos son now flys the C-17 in the Air Force.

 

[Mid7night]

Wow Aviator, that's awesome! Looks a lot like what I expect mine to. Do you remember what span it was, and what it weighed as a static model?

 

[Aviator08]

Wow Aviator, that's awesome! Looks a lot like what I expect mine to. Do you remember what span it was, and what it weighed as a static model?

It was 60" wingspan, and not sure I ever weighed it. I can ask my co-worker to weight it if you want.

Tim

 

[Mid7night]

It was 60" wingspan, and not sure I ever weighed it. I can ask my co-worker to weight it if you want.

Tim

Ah ok. Mine will be 48" span, but if it's not too much trouble I would like to know the weight for a comparison estimate. Thanks!

 

[Jaxx]

This is really cool! What CAD software are you using?

 

[Mid7night]

This is really cool! What CAD software are you using?

I use a program called MOI3D. It's not free, but it's actually quite affordable for the powerful features it has. I won't go into all of them, but one of the nice things is it will export a DXF or PDF of your 2D line drawings - at the correct full scale - so I can easily lay out cut plans and print them right away without any scaling fuss. PM me if you'd like to know more.

 

[Mid7night]

Cutting started a couple nights ago, and last night I glued the first bits together. I'm hoping, I think the nose is the most 'tedious' parts of this build to assemble. It wasn't too bad, but it certainly wasn't on par with typical FT-simple techniques. Certainly repeatable though, so I'm happy.

Also rolled and glued the nose-coupler, that will be on the front of the main fuselage and the nose will slide on.

 

[Aviator08]

Ah ok. Mine will be 48" span, but if it's not too much trouble I would like to know the weight for a comparison estimate. Thanks!

I had him weight it , and he said it weighed 3.3 oz. I didn't think that is right , so I asked him to weight it again.. he said it came out the same. I think it might be more like 3.3 lbs. Sorry I don't have a more definitive answer for you.

 

[Aviator08]

The nose looks good.

 

[Mid7night]

Fuselage assembly!

 

[Ricci]

Subscribe! Awesome!

 

[JimCR120]

Though it might be tedious, the extra panels on the nose look very nice. I'm interested in the technique and being able to apply it to other builds.

Was the number of panels around the nose determined by the drawing program or did you figure the dimensions? And then how did you determine the the curves to be cut on a flat board that would render a curved cone nose?

 

[Mid7night]

Though it might be tedious, the extra panels on the nose look very nice. I'm interested in the technique and being able to apply it to other builds.

Was the number of panels around the nose determined by the drawing program or did you figure the dimensions? And then how did you determine the the curves to be cut on a flat board that would render a curved cone nose?

Thanks, I'm pretty happy with how it's looking so far.

I picked the number of panels to be 8, as a balance between simplicity and looks. More than 8 looked great, but started to look like a serious CHORE to even cut out, let alone build. Less than 8 and it really lost the shape of the original.

The concept is basically the same as a beachball construction; divide a curved surface into sectors and 'unwrap' it. I also picked 8 sections because more than that would've been a giant pain to model and unwrap, because I had to do that part manually. I tried exporting to Sketchup, because there are plugins that will unwrap models for you, but I couldn't get them to work quite right, at least not for this. To unwrap the nose, I had to first divide it into the 8 sections radially, and then had to further divide it longitudinally, so that I had some lines to unwrap from. It's not exact, because I'm taking a compound-curved surface and unwrapping it (approximately) into a flat surface, but it's close enough that you can bend it to shape when building. You just have to take your time.

If people are interested enough in seeing the unwrapping part, I can try to take some snapshots of the nose before/during/after, so you can get an idea of the process.

The same technique applies to the aft-body, as well as the gear pods; which is what I got put together tonight!

 

[Jaxx]

Mid7night,

It looks great! How long have you been working with CAD software?