Hey guys, I'm planning to build my first quadcopter using the plans (and knuckle hubs) for the rotorbones H-quad as a bit of an ongoing project (meaning tons of questions as I collect parts) and I've got a few frame-related questions off the bat.
(1) I bought enough 1/2" square by 36" long poplar to build either 5 quads with 10" legs or 6 quads with 9" legs, but I'm honestly not sure which to go for. At $0.59/foot, material is cheap and I've got 18' of the stuff to work with so I'm not exactly wanting for material, but at the same time I can make more spares using 9" legs and not have any wasted material. would making the copter an inch shorter in width and length make it noticeably harder to fly, or have control boards gotten good enough in their ability to correct for airframe twitchiness that it wouldn't matter? obviously I'd have to stick to an 8.5" or smaller prop to keep from running the props into one another, but given that just starting out I'm not going to be doing FPV or carrying anything of any appreciable weight, I don't think the slight decrease in thrust from taking 0.5-1" off of the blades would be much of an issue, would it?
(2) I'm going to print out the .pdf plans for the frame and spray glue it to some material I have and cut it out either with a band saw or a scroll saw, depending on which I can get set up (I have access to both, but the scroll saw needs to be set up and bench space found for it, and the band saw quite desperately needs a new blade and some TLC), but I'm not sure which material would be best. I think I might have a bit of a material hoarding problem, as I currently have 6 8x10" sheets of 0.093" lexan/polycarbonate, 3 8x12 and 2 9x12 sheets of 0.125" kydex, all of which is basically in an as-bought state (uncut/undrilled, still has protective film where applicable), so I doubt I'll run out of material any time soon. Kydex is SOOOOO much nicer to work with than lexan when it comes to cutting (drilling is about even though, since I've got access to a drill press) but I've also noticed it's a bit more flexible than lexan, despite being thicker... but with the largest part only being 80mm/3.14" square and very well secured, would rigidity really be an issue? I've read with some h-quads that low torsional rigidity can cause REALLY nasty flight characteristics (as in flying 3-4 mistakes high might still be too low to prevent a crash) so I obviously don't want that to happen, but the design of the rotorbones quad seems to be more torsionally rigid, and from all of the shenanigans the FT crew has put the design through, if rigidity was an issue I think it would have reared its head by now, and with the potential for going an inch smaller, wouldn't the chance of flex be even less?
If you've made it this far, thanks for putting up with my late night ramblings, and thanks for any and all help! I'm sure I'll have a bunch more questions as I get into the more technical side of the build (motor/ESC/prop/flight control board selection and setup, and of course, pilot calibration ) so brace yourselves!
(1) I bought enough 1/2" square by 36" long poplar to build either 5 quads with 10" legs or 6 quads with 9" legs, but I'm honestly not sure which to go for. At $0.59/foot, material is cheap and I've got 18' of the stuff to work with so I'm not exactly wanting for material, but at the same time I can make more spares using 9" legs and not have any wasted material. would making the copter an inch shorter in width and length make it noticeably harder to fly, or have control boards gotten good enough in their ability to correct for airframe twitchiness that it wouldn't matter? obviously I'd have to stick to an 8.5" or smaller prop to keep from running the props into one another, but given that just starting out I'm not going to be doing FPV or carrying anything of any appreciable weight, I don't think the slight decrease in thrust from taking 0.5-1" off of the blades would be much of an issue, would it?
(2) I'm going to print out the .pdf plans for the frame and spray glue it to some material I have and cut it out either with a band saw or a scroll saw, depending on which I can get set up (I have access to both, but the scroll saw needs to be set up and bench space found for it, and the band saw quite desperately needs a new blade and some TLC), but I'm not sure which material would be best. I think I might have a bit of a material hoarding problem, as I currently have 6 8x10" sheets of 0.093" lexan/polycarbonate, 3 8x12 and 2 9x12 sheets of 0.125" kydex, all of which is basically in an as-bought state (uncut/undrilled, still has protective film where applicable), so I doubt I'll run out of material any time soon. Kydex is SOOOOO much nicer to work with than lexan when it comes to cutting (drilling is about even though, since I've got access to a drill press) but I've also noticed it's a bit more flexible than lexan, despite being thicker... but with the largest part only being 80mm/3.14" square and very well secured, would rigidity really be an issue? I've read with some h-quads that low torsional rigidity can cause REALLY nasty flight characteristics (as in flying 3-4 mistakes high might still be too low to prevent a crash) so I obviously don't want that to happen, but the design of the rotorbones quad seems to be more torsionally rigid, and from all of the shenanigans the FT crew has put the design through, if rigidity was an issue I think it would have reared its head by now, and with the potential for going an inch smaller, wouldn't the chance of flex be even less?
If you've made it this far, thanks for putting up with my late night ramblings, and thanks for any and all help! I'm sure I'll have a bunch more questions as I get into the more technical side of the build (motor/ESC/prop/flight control board selection and setup, and of course, pilot calibration ) so brace yourselves!