looking good! Would you mind sharing where you got those files?
Just a point but is what you have printed so far in ordinary PLA or the light weight version? This foams as it prints which I believe is what they suggest should be used.
Inq
I am impressed by your ability to use ABS in such thin walled structures without distortion.
I do fear a 50% weight penalty may have a detrimental effect on its flight characteristics.
For the same airframe the power to fly is directly proportional to its all up weight so as a minimum you will need a 50% more powerful motor and prop combination to achieve the same performance. This in turn will significantly reduce the flight duration using the same weight of battery. A bigger battery would of course increase the all up weight still further.
It will be most interesting to see the finished plane.
That is very impressive indeed.
Motor, battery and servo?
It will be interesting to see how the all up weight compares when it is in a 'ready to fly' state. If you can indeed keep the excess down to the 72g from using ABS you should be fine although it will fly that bit faster and crash a bit harder.
Snap! on using filament for hinge pins. The working printed sprung undercarriage on my Antonov AN2 uses it.
View attachment 231125
570 gms of thrust should be good thrust to weight should be 1.5:1 for beginner planes and 2:1 for aerobatic????
I'm sure the weight will go up. The only thing I don't have accounted (I think) is the reinforcement. It has slots above and below the built-in printed spar: "Press in and glue a piece of PolyAir, PLA, PETG or 1.5 mm carbon rod into the top and bottom opening to create a wing spar and improve the rigidity of the wing." I'll use fiberglass tow I have laying around. I've noticed over the years how they've improved the design of the assembly. This one was easy to assemble and everything looks to be true. Even the very slight dihedral and washout looks to be consistent for left and right wings. I thought it was real clever how they use the filament (1.75 mm ABS in my case) as the hinges for the ailerons, rudder and elevator. It just slides in and can easily be removed and replaced.
View attachment 231114
Inq
Yes the struts have springs in them. The springs came from ebay. Quite soft to give over an inch of vertical travel. At that point the prop would also touch the ground.
I do agree a printed undercarriage is comparatively weak to a spring steel version.
I found the biggest issue is not the strength of the strut itself but the strength of its 'joint' assembly at the fuselage. Most spring steel undercarriage it is secured over an area in the fuselage reducing the point loads to an acceptable level.
However you will likely find with an all printed plane it is not only the undercarriage that will need 'delicate' landings.![]()