Flitedesign 3d
Elite member
Great and simple design but the problem on b-25 is its gull wing design so the wings are angled between the outboard and inboard flaps
Billy Mitchell Was Right
- Thread starter BATTLEAXE
- Start date
Wildthing
Legendary member
Pusher prop is basically a reversed prop.
Quick search at master Airscrew in 9" tri blade only the 9X7 is made.
https://www.masterairscrew.com/collections/3-blade/9
Monte.C
...
I think you can also do what I'm doing for one of my tailplanes. Tie the two together with a stiff wire maybe 1.2mm+, shaped with two coplanar right angles like a very wide "U". Embed each end section - each short length - into the control surface from below, leaving the center length that ties the two together as close to the hinge point as you can get away with. Cut out whatever clearance you need to from the nacelle structure. So you can use 1 servo and 1 control horn to run two flaps. That's what I'd try.
OH - @Flitedesign 3d just gave the same answer. My bad.
Flitedesign 3d
Elite member
You meant @The Hangar
Monte.C
...
Oof. My bad X2. And yeah, non-coplanar flaps (dihedral) are a problem for this application.
Shouldn't it still work with the proper bend though?
Flitedesign 3d
Elite member
Nope, unfortunately not, it would need some cardan joint, it might even work if you use a piece of semi-stiff plastic tube as a cardan joint since the anhedral is only a few degrees
BATTLEAXE
Legendary member
Thanks for the info bro. That might be where i get these depending on great hobbies price for shipping
Vimana89
Legendary member
I'm really impressed at the amount of detail going into this one. I still have to take a shot at making a twin engine, let alone one that intricate. I'm sure its going to look great and fly nice too, sounds like with that engine setup you will have more than enough thrust.
BATTLEAXE
Legendary member
It will be more power then two C packs for sure. I like goin with mor power then i need, its nice to have it. Plus that combo will fit any other twin i build and then some.
Hey you should try a twin wing
Apple Pie
Elite member
Thanks for all the ideas on the flaps. I'm going to try the bent wire connecting the inboard and outboard flaps and a single servo for each wing. I think the anhedral is small enough to allow for this idea.
Today was "how much did you screw up in your modelling" day? The answer fortunately was "not that much so far"! A few things worth noting: The airfoil profile on the B-25 is really quite deep compared to other planes I've built so I ended up forming the leading edge of the lower wing skin and bringing it up to meet the upper wing skin. I've haven't seen that on any of the master series planes I've built so far but it looks really sweet on this one. I also screwed up where the engine mounts go on the wings and cut them out about 5cm too far outboard so the nacelles won't flow back through the break in the flaps. I'll have to move them inboard and fix the drawings. Otherwise I'm quite happy with how its coming together, though much of it is just green taped for testing and alignment purposes.
Today was "how much did you screw up in your modelling" day? The answer fortunately was "not that much so far"! A few things worth noting: The airfoil profile on the B-25 is really quite deep compared to other planes I've built so I ended up forming the leading edge of the lower wing skin and bringing it up to meet the upper wing skin. I've haven't seen that on any of the master series planes I've built so far but it looks really sweet on this one. I also screwed up where the engine mounts go on the wings and cut them out about 5cm too far outboard so the nacelles won't flow back through the break in the flaps. I'll have to move them inboard and fix the drawings. Otherwise I'm quite happy with how its coming together, though much of it is just green taped for testing and alignment purposes.
Wow, that looks amazing! Will you be releasing plans for it?
"Corpse"
Legendary member
Maybe instead of the bronco, you could try this!
Apple Pie
Elite member
Hell yes I will! I'm doing all the drawing and cutting with my CNC software and needle cutter (Vectric VcarvePro) so its all vector based stuff. I regularly use Inkscape to convert PDF to SVG for cutting, so I'm pretty certain I'll be able to reverse the process to put the SVG files back into Inkscape for full size plans. Never done it but it seems like it should work. I'll also post the SVG files for those with cutting abilities. I also plan on using some 3D printed parts in mine for the gun turrets, bomb bay door brackets and such so I'll post the STL files for any of those as well.
I have been a complete freeloader using all the plans generated by the awesome people on this forum so this one I'm giving back 100%. I kind of hope someone else wants to build this beauty sometime after I'm done (heck I'll send out the files before I'm done if anyone loves to alpha build). Plus, I've got two other planes in mind that I need to model up one day for myself and others. A CL-415 to update the one I built last summer and a Twin Otter on floats. Oh god the crazy stuff I have in my head...
Haha, well @corpse has a good point - this would be a cooler build than the bronco! I've ordered a needle cutter and it still hasn't show up a month later...
Hopefully it'll have arrived by the time plans are out.
Apple Pie
Elite member
Warning: A fifty sheet box of foam doesn't last long once the needle cutter is up and running...Haha, well @corpse has a good point - this would be a cooler build than the bronco! I've ordered a needle cutter and it still hasn't show up a month later...
Haha, I believe it!
Michael9865
Elite member
Exactly. The struggle is real. LOL
BATTLEAXE
Legendary member
That looks awesome bro! I really like the wing shape. So much more scale then my plans. I too noticed the depth of the wing for scale and found the center line/CG area of the wing didn't work in the math. so i moved my single spar forward by 1/2" in the wing and positioned on fuse. This in turn brought my intended CG, term used loosely at this point, a half inch more forward. If there needs to be weight this plane looks like it needs it in the front. Even though the two motors will end up mounted, as per the drawings, 5" in front of the center spar, I still want the option for the biggest battery i can fit in for flight time. I think it would be cool to mount a cam on all the gun points for aerial footage with an on-board cam
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