Sounds good to me
Great!!👍👍
Generally solid advice for building a fast plane. In general, with drag reduction you get the big improvements by improving the overall shape of your plane (planform, airfoil, etc.) but this doesn't really matter without all the small improvements (covering gaps, removing sharp corners etc.).
In general 3D printed designs seem very resistant to flutter at least. I think the limitations of 3D printing tend to result in a very stiff airframe, especially if using normal PLA and infill instead of vase mode or a ribbed structure. 3D printed materials, and especially PLA also tend to have a very low coefficient of restitution and fairly high damping compared to something like fiber glass or balsa which means it's harder to build up big vibrations since the energy gets absorbed. The only time I've had major issues with flutter was on a plane going only about 60 mph and it had these huge all moving vertical stabilizers driven by little 9g servos (wingspan is 8 ft for a sense of scale). This was very much an issue of a bad design decision and most likely developed in the push rods, and even then, I was able to back off the throttle and land totally safely
They didn't 😒
Oh, too bad...
That sounded sarcastic 😂
Sorry if it came across that way! It wasn't meant to be😂👍
Nice!!👍
I enjoy what you are doing and since we look at things differently , it's nice to let the "newbee's" see different aspects in designing planes. I have heard about baking the plastic plane in too much sun(temp wise), is there any info out there if the sun's rays are detrimental to the structural(not temp) segment over a period of time?In general 3D printed designs seem very resistant to flutter at least. I think the limitations of 3D printing tend to result in a very stiff airframe, especially if using normal PLA and infill instead of vase mode or a ribbed structure. 3D printed materials, and especially PLA also tend to have a very low coefficient of restitution and fairly high damping compared to something like fiber glass or balsa which means it's harder to build up big vibrations since the energy gets absorbed. The only time I've had major issues with flutter was on a plane going only about 60 mph and it had these huge all moving vertical stabilizers driven by little 9g servos (wingspan is 8 ft for a sense of scale). This was very much an issue of a bad design decision and most likely developed in the push rods, and even then, I was able to back off the throttle and land totally safely
I've not had issues with damage from UV and I'm mostly using ABS which is not particularly UV resistant. You get a bit of yellowing, but the amount of time the planes spend in the sun isn't that long in absolute terms - a few hours maybe once or at most twice a week when the weather is good. My oldest plane I still have together is my F-106. I've replaced some of the parts more recently, but there are still parts from maybe March or April last year that are still going strong with no noticeable damage - I know for sure the vertical stabilizer has never been replaced for example.
I was interested in if there is data available on the ABS or other material that you use over a period of time, does' the chemical breakdown effect the structure. How about the printing process? For instance, what if a engine mount sits around for 2 years, can it handle the bending. torsion, vibration, or self destruct and hurt someone.. This is all new stuff.
I can only speak to the kinds of applications I have used 3D printing in but like I said, no noticeable damage from being exposed to normal conditions for RC planes for over a year. The F-106 is a big, heavy, 4+ kg plane and I fly aerobatics with it every flight, so it's not some lightly loaded part that's just hanging out. However, I can't really speak about exposure to hours of vibration like in a motor mount since EDFs tend to be very low vibration as a whole. I also can't speak about chemical exposure like with a mount for a gas engine, but ABS in general is attacked by solvents like acetone, so I wouldn't recommend trying to use it with a gas engine
