Plates are 2.4mm carbonfiber/kevlar Red over cf cross lay. All parts are cut. Its 12" across so the arms are shorter. Aluminum folding arms (16x12mm cf tube) I tested the heavy 16 mm tube and its very strong. I designed the retracts with 2 motors per side and can each hold a 4s-10000 battery if I want to place them there. It is designed to hold my DYS eagle eye. I have the (8) 5010-360 motors and 18 x 5.2 folding props. Will be taking lots of pictures and uploading as I go along. motor to motor is 1225mm. The motor mount are my design with 4 rubber mount points that can be individually adjusted-made from 3mm cf (I tested the mounts with and without the rubber and gained about 40% less vibration). e-calc comes out to 58 min. hover with the 2 batteries and it has room for 4. Ill load pictures up to my website dp-designs.biz for easier viewing
Attached are pics of my plates on my cnc, the dys I built and its custom stand and the first design Hex with 2212-920's and 11" props that flies very stable.
A few more pictures:
RCtimer Distribution board with 5v and adjustable 10-20v power.
dual motor retract with mount: Mount is not sturdy enough so adding a 5th standoff in the center.
Another view of retracts:
Bottom view with DYS mount points and retract mounts installed:
Only half of the screws installed to check for fit and its very strong. Installed the 16 x 12 mm arms and there is no give even with the full uncut 500 mm length. I have HP blue series esc's right ow but I like the Arris 30a 2-6 OPTO's that I will go with in final testing. I ran the motor with different props and esc's on my thrust test stand and the Arris esc's had the quickest response and best electrical values of the 4 I tested.
recieved the esc's today and arm tubes Tuesday. Now have everything to assemble. I was running the motors on the torque tester and found that to 18x52 folding props I have even though I put them on a quad beam scale and matched them up to an eye lash of each other there is a lot of vibration.. I am going with the 17 x55's t-motor type. They balanced great and vibration to a minimum. Tonight I will be balancing the motor/propeller combo on the tester. I have a foil type tape that I use on the motors for balancing that sticks well. i do the motors then recheck with the quick connect spin on adapters and props. Ill find if its worth it. I powered up the Pixhawk yesterday. This will be my first but I have been doing a lot of reading and videos. All my builds to daye have naza lite, naza V2, JIYI P2 and P2 Pro. Lots more tweaking with the pixhawk.
I need to change my cnc over to Plasma cutting. I have been slowly designing a hexa-copter with the same style design as my octo above. I did a bunch of work last night on the models and think I am ready to cut them before I change over. I have all the parts for 2 and I am cutting a 600mm x 600mm CF plate tonight that fit all the parts plus extra. here is my drawing with all the models inserted and positioned on a 600x600mm drawing that I can directly bring into BobCad to generate the code for the cnc. The hex plates are 280 x 280, just 20mm smaller than the octo.
Here is the drawing and a snapshot of the plates assembled to check fit.
Packed in a lot of parts.
I have the DJI 900 mhz Data Link/ground station that I will be doing some flights with tomorrow with my modified/customized Tarot 680 (the tarot upper and lower plates and 4 folding arm mounts are the only original parts on it). It flies quite well and stable so I am working my way up to the DYS gimbal flying with a brick weight in place of my camera. The sky's the limit from there!! Don
You shed a lot of weight on your plate design (thumbs up). maybe 3mm plates would have been better?
This should be a very lightweight heavy lift machine.
Hopefully stiffness is not sacrificed.
Let me know if you are happy with those folding arm clamps, I debated if I should have gotten those automatic arm kits.
I decided against trying those ones and unknowingly bought the worst ones ever made.
The red octo is 2.5 mm, I was suprised how stiff it was with only half the screws in it. Its very stiff with the the inner circle of standoffs tied from bottom to battery mount on top.The hexa is 2 mm-bought it very reasonable and it is strong, almost feels too stiff? I did make all the webbing about double on the hex. I will change the octo before/if I make another. It's very rigid but hard landings.. Ill see. These motor mounts out of 2 mm will be for small motors. I made a bunch of adjustable vibration dampening ones out of 3mm.
I tried to find what difference in rigidity between the 25mm x 1mm wall tubes compared to the 16mm x 2mm wall. I know with most metals, when it comes to thin wall tube, the wall thickness has little to do with it, the larger the diameter the stronger. It just seems, with the way CF is constructed with cross fiber layers, that the wall thickness would add a lot more strength in the mix as compared to metal structure. Just can't seem to find anything. I put the tubes in a machine vise while firmly held between 2 aluminum clamps, a dial indicator 200mm from the closest clamp and loading it at the end with digital scale, I didn't notice much difference in deflection.easy to set up again and will try it with some 500 mm aluminum 16mm tail boom tubes to compare also. Can then make in all kinds of colors-sure the aluminum will work great up to 350? mm or so. And I need to write it all down this time.
I also designed a custom fit, 2 piece case with a 14mm square aluminum heat sink for the Arris 30a esc's (minus heat shrink) that I am pleased with-I did a little re-design for easier printing and a little heavier on the material. Local community College printed me a couple test pieces and its now tweaked where it needs to be, Here is a pciture. As you can see i am making everything a bit larger-heavier walls. Almost finished with bottom but top needs to grow a little. It took 47 min. to do the set with a makerbot replicator.
I will be using the side folding? on the hex like my Tarot 680. Takes up the whole back seat though. They are strong, cheap and more companies making replacements.
I had my 680 about 150 miles away at my sisters barbecue and took off without calibrating the compass. It immediately headed for my house but a tree was in the way. No major damage but broke off one of my 3 mm thick motor mounts and 3 props and didn't brake the pivot end. I was very impressive that day. Glad I brought more than one with me.
Have motor wires extended and the esc wires shortened. distribution board wired up and added the pixhawk power supply to the board. The distribution board has a good 5v and adjustable 10-20v power supplies. I will use 5v as a backup for the pixhawk for redundancy. it should switch over if there is a problem with the pixhawk board.
The dual motor retracts are very strong and sturdy
I will be installing motors, setting the throttle the esc's. I have powered up the pixhawk and have the basic setup done on that and the taranis plus. I am amazed how much stronger the 16x2mmwall tubes are compared to the standard 1mm. I have the arms cut to 470mm and with the vibration dampening mounts the octo will handle up to 20" props. Should be putting the top plate on today-before installing motors and arms so everything will get very stiff.
I have been thinking on lighting and decided to go with red at the back facing down and back, then amber in the front facing forward and downward. I considered lighting like my boat - I believe same as plane but it just seems so much easier to look up and see red and know its facing away. My boating class, red-right -returning is taught for orientation but an automotive lighting is a no brainer.
Then I have 2 high intensity white that I will mmount facing forward, I have a 12 v transmitter switching power supply for them.
Watched (and still watching) many videos and read a lot of pages. I have have the Pixhawk and Taranis Plus working pretty good. Pixhawk keeps amazing me. Dual power supply, dual sensors and cpu - Its a lot for the money. The taranis is also pretty kool too. Have logical switches, curves virtual switches and 6 way switch for all the flight modes. Should be reading all the Pixhawk telemetry right to the taranis screen next week. No need for osd on the FPV screen! Pretty nice to have all the info without the fpv screen.
Motors installed on arms, wires run for lights controlled through 2 switches on the radio. 5 and 12v power set up. The esc cases came out great-they will be installed tonight.
I am up to using 13 of the 16 channels available on the RX.
Maybe see it in the air soon. Lots of projects going so only have an hour or 2 every few days so its going a lot slower than I was hoping
The folding arm mounts seem loose but when the bolts tighten they do seem very stiff.
The rctimer motors I am using are inexpensive but seem to be of good quality. I did order a set of high grade ceramic bearings to replace the existing ones as I think this is the weak link of these 5010-14's. I will be running them on the test stand and compare the before and after.
installed the ceramic bearings and checked all arms/motors with props on and vibration was almost "0" on every one. Also the watts went from 164 to 157 with the new bearings + or - 1 watt. I also modified the props by sharpening the bottom/leading edges close to the motors to give better air flow into the windings. The temp went down about 10 deg. across the board too. Hope it didn;t weaken the props but I don't think so.
The FC Model folding arms are pretty sloppy! I put clear silicone on the arms before inserting then tightened them to help make them stiffer. The bolts are a little short also, I tightened the first lock nut until it snapped and still not al the way engaged on the thread (also some side play in the arms) Used lock tite then tightened as far as I thought possible.
Here is the finished Octo. It is a lot heavier than I thought 4.48 kg. I had motors running and all directions checked. tried to arm the machine but get a deep high-low two tone beep. Something simple I am sure. Lots to learn. I am still setting up radio to give sounds for the 6 position switch. Hopefully will be able to take it outside and at least make the props spin in the next couple days. Cold and rainy here plus I get out of work about the same time its getting dark!