hi I mostly use the xcarve to cut carbon fiber, however the normal bits or the cheap bits don’t last very long because fracturing of the fibers creates considerable abrasion on the cutting tool. the life of a bit when cutting carbon fiber is almost 5 times less than cutting wood. buy some inexpensive bits to start of though and judge the life for yourself. i found these bits http://www.precisebits.com/products/carbidebits/fdrouter.asp and they work really well with carbon fiber or fiber glass carving. however remember machining carbon fiber requires higher spindle speeds than metals, but lower feed rates. below is a good guide to selecting bits for Composites:
http://www.mmsonline.com/articles/tool-selection-for-composites
It also doesn’t leave all the weird burrs that HDPE does, thankfully! Machines with nice, clean chips using a sharp tool. I’ve not had any trouble with it structurally before.
1 Like
yeh loud and clear thought of all that.
ive build more than a dozen drones. bit of an obsession. and i aware of the conductive property’s. my first one grounded and smoked. and i knew about it before hand. which is why i hate wiring harnesses, because carbonfiber frames are often sharp. which is why i asked about using the xcarve to cut it. conductive dust and crap.
and i really want to build a power distribution board to. TBS and every one Else’s not so secret, secret is that many of them are not carbon fiber, but rather fr-4 circuit boards made of fiberglass and a nice black solder mesh. and if i can mill out a board like that with my new xcarve… i damn well will. lol the guys over at the evvblog forums told me it cant be done. “you cant pass 30amps through a single trace.” watch me. every one else does it on there model. ill figure it out. ok maybe closer to 15-20amps, but Ive seen some high yield motors on pcb distribution boards. and ive pulled 120amps total through a 1in by1.5in board my 6y tricopter. so it cant be to bad. just got to test it.
thanks guys
If you’ve been in the smoking/burning quad situation with CF, then you have learnt all the lessons you’ll ever need to learn 
TBS did do one of their early combined frame/distribution boards in CF and used embedded/resin covered traces but was very easy to crack traces with even a tiny amount of flex. So it would work on the ground, would work in the air, then you went full throttle and it fell out of the sky.
Even Tarot’s “100% CF” frame kits use a FR4/G10 board as their combined frame/power distribution boards. But that is Chinese marketing for you.
I’m like you, I like combined frames and power/signal distribution but I’ve gone back to separate systems now purely because of all the problems with them. Good old independent PDBs for me and wiring looms again. Just makes replacing a frame so much easier and cheaper.
It’s why I like the idea of multiple, flat thin sections to build up the frame thickness with a few bolts holding it all together. if you snap an arm, you only replace that section and your flight controller, FPV gubbins, RX etc. can be left in place. So your arm section then only has the motors and wiring for the motors mounted to them, everything else is on the main chassis. Then takes ten minutes, in the field, to fix a broken arm rather than having to break down the whole thing. I even tend to keep the ESCs inboard now depending on the design.
Incidentally, cutting a PDB is easy on the X-Carve, nice big pads, nice big holes and you end up with exactly the right number of sources you need and the shape you want. My hex uses one I cut on the X-Carve using standard single sided FR4 circuit board blank and that can theoretically pull 130 amps (although never gets close) and I’ve never had any problems and that has close to 50 hours flying time on it.
One thing I am playing with is to use very thin sheets of materials to build up a full frame and I’m happy to share this although not the actual frame design. So you’d use a thicker sheet of HDPE for your arms and a frame, second sheet of FR4, single copper sided, for your power distribution, then a thin insulating HDPE sheet, then another FR4 copper for signals from the FC to the ESCs and to the FC from the RX. Then another thin, insulting HDPE layer etc. So you end up with basically a laminate (when bolted together) which is strong and light but also with minimal wiring, has bays for the expensive electronics to protect them and the whole thing rebuildable in the field. A best of both worlds, sort of.
Cheers
Ian