Anybody else scratch building tonight?

mastermalpass

Elite member
Su-35 repaired and ready for another go!

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mastermalpass

Elite member
Measuring a Mirage 2000C Blueprint around a 70mm EDF.

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I'll probably mount the EDF a bit further forward than here, I was really just sizing up the fuselage diametre to the nozzle. I don't want the cowling to go any narrower than the EDF itself - I'm sure it will be fast enough without any compression and as this will be my first EDF, I want all the thrust I can get.

One part I'm excited about, is that an existing landing gear set I have will just about fit in the wings. The nosewheel is a little awkward, but I don't mind squaring off a little bit of the underside forward fuselage to get it where it needs to be.
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On top of that, my Mobius camera will fit quite easily into the cockpit:
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So, CoG allowing, this plane could house some pretty cool giblets!
 
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mastermalpass

Elite member
I'll probably mount the EDF a bit further forward than here, I was really just sizing up the fuselage diametre to the nozzle.

Or, maybe that's exactly where the EDF needs to be! I measured the weights of all the main parts, including the camera, then calculated the moment forces from the CoG. I've 'compressed' the length of the plane for ease of reading on this chart and found that with a nosegear and a camera up front, I need all the tail-weight I can get. Once all the foam is added on, I'm hoping the wings, vertical stab and servos (mounted pretty close to their control surfaces) will actually result in a net-tail heavy design. Notice the position of the battery - that is as far back as it can fit. I have loads of space to move it forward if I need more nose weight, so ideally, the build will add more weight to the tail than the nose.

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Brian B

Elite member
About time I made my first EDF. Making a pair, this J-20 for a friend, and an F-22 for myself. Both 70mm. Not bad for one evening, from start of cutting to this stage (not including watching one episode on Netflix). Waiting for carbon fiber to arrive for reinforcement, and start on the F-22 tomorrow.
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cyclone3350

Master member
First attempt at heat shrink covering has been “interesting”…
I ended up using a soldering iron on low temp to try to cover the inaccessible space below the elevator. Don’t know why the kit instructions didn’t suggest covering before assembly. 🤔
Oh well - if I do this again I’ll know for next time!
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A covering iron has a narrow point to get in the small spots and there is a trim iron to get into really tight spots. I luv your improvisation & if it works, that's is all that counts. Looking good(y).
 

The Fopster

Master member
Of course, I was just wondering if the entire plane was covered in balsa, without any ribs or anything like that.
There are a few plywood formers, and the rest is just thin sheet or thicker blocks carved and sanded to shape. The wood is amazingly light - the plane will be about 600g ready to fly with a 2200mah 3 cell battery.
 

shadeyB

Legendary member
Very little. Didn’t measure it, but I’d guess maybe 15g? I doubt it weighs any more than paint.
I Personally don’t get hung up on the weight of paint, coverings or even the additional coats of varnish, minwax or polycrylic
build it
paint it
and fly it like it’s on fire
main thing is have awesome fun whether that is scale, 3D or flying into a tree 😂😂😂
not forgetting dogfights, flying through football goals, under bridges and doing the odd occasional lawn dart move 😂😂😂

looks epic buddy, can’t wait to see it finished and flying where it belongs 👍😁