3D Printed 50mm EDF Trainer Jet
- Thread starter telnar1236
- Start date
Captain J
Well-known member
man thats way better than abnormal PLA…that stuff freaks me out…
Is that like anti-PLA? It explodes if it touches regular PLA??
Captain J
Well-known member
😂😂😂😂😂😂😂
telnar1236
Elite member
Like Mr Man said, normal PLA, though hopefully it should also work if you want to print it in ABS. It might be a bit heaver using PLA than LW-PLA, but it's so much easier to print and less fiddly that in my mind it's worth it.
telnar1236
Elite member
Flying weight should be about 900g with the battery accounting for about 200g of that. There are currently some bits that are overbuilt, though, so I should be able to save a bit for the final version. Thrust should be about 950g, so the plane should have plenty of power.
Captain J
Well-known member
that kinda just answered what was gonna be my follow up…”how difficult is LW or Active” is where my brain was going.
plans looks absolutely amazing.
Captain J
Well-known member
thats not bad though. how much thrust is the edf you are using producing?
telnar1236
Elite member
I don't want to give the wrong idea - LW-PLA is actually still pretty easy to print, especially in designs from better designers than me like Eclipson or 3DLabPrint. You just need to design around its limitations which basically amount to being unable to use retraction and supports not detaching well. Also, if you don't have an all metal hotend, running at 245 C slowly destroys the PTFE until the printer eventually jams and you need to replace the liner (easy and cheap to do). Overall, for "heavy" planes like jets, I think PLA is better, and ABS is best since it's a lot stronger than LW-PLA which means you make designs that are nearly as light, while for "light" planes which need less strength PLA and ABS are too strong so the planes always end up overbuilt to make them printable and LW-PLA is the best option if you can design for it.
telnar1236
Elite member
I'm using this EDF:
It should give about 950 g of thrust according to specs, though it probably will give less than that in practice. Still, with how efficient the short straight through duct on this plane is, I think it should have plenty of power.
tomlogan1
Elite member
Thought this was a 50 mm fan?!
telnar1236
Elite member
Whoops, looks like the seller changed the listing. This is actually the unit I'm using.
telnar1236
Elite member
The FMS 50mm fan gets 880 g of thrust on paper, so it should also be a drop in option.
telnar1236
Elite member
The plane is mostly put together now.
My fears about it being tail heavy unfortunately turned out to be true. With 50g of extra weight in the nose and a 2200 mAh battery instead of the intended 1600 mAh pack, it just about balances at 25% of the chord, but I want it to balance at closer to 10-15%. I'm currently debating trying to fly it as is, or redesigning to fuselage a bit to shift the CG forwards. It's modular, so I only need to reprint half the fuselage to do this and can keep everything else.
My fears about it being tail heavy unfortunately turned out to be true. With 50g of extra weight in the nose and a 2200 mAh battery instead of the intended 1600 mAh pack, it just about balances at 25% of the chord, but I want it to balance at closer to 10-15%. I'm currently debating trying to fly it as is, or redesigning to fuselage a bit to shift the CG forwards. It's modular, so I only need to reprint half the fuselage to do this and can keep everything else.
Captain J
Well-known member
man, i am super jealous of your skills. i just started 3d printing and have no clue what i am doing. cant wait to see it fly.
telnar1236
Elite member
You'll get there before you know it. I learned mostly by working with and to replicate Eclipson and 3DLabPrint, and they're both still far better at designing these things than I am.
Captain J
Well-known member
normally i can watch tutorials and be rollin…not with 3d printing 😂
telnar1236
Elite member
I think I'm too sketched out by the aft CG location to try it as is so I'm going to reprint the fuselage (and possibly some other parts to reduce weight depending on how long it takes). I'm hoping to fly it for the first time over Memorial Day weekend still.
I'm still working on fixing all the fuselage ducting but these pictures should at least show the idea. The EDF is moved 100mm forwards to sit over the wing instead of in the tail. At the same time, the ducting in the nose is flatter to allow the batter to sit lower down and therefore further forwards instead of needing to sit under the taller part of the canopy. The duct still keeps a constant cross-sectional area so it should still be fairly efficient, but it won't be quite as efficient as the straight-through design I originally had.
The difference between the new and old EDF locations is pretty significant, but the battery will be able to move both further forwards and further backwards than before, so I should have more control over the CG range.
I'm still working on fixing all the fuselage ducting but these pictures should at least show the idea. The EDF is moved 100mm forwards to sit over the wing instead of in the tail. At the same time, the ducting in the nose is flatter to allow the batter to sit lower down and therefore further forwards instead of needing to sit under the taller part of the canopy. The duct still keeps a constant cross-sectional area so it should still be fairly efficient, but it won't be quite as efficient as the straight-through design I originally had.
The difference between the new and old EDF locations is pretty significant, but the battery will be able to move both further forwards and further backwards than before, so I should have more control over the CG range.
Captain J
Well-known member
was it crazy tale heavy?
