I always prepare my new mini quad frames by washing off carbon dust and chamfering the edge using a file or piece of sand paper, which is good for your carbon fibre frame.
Why prepare new carbon fibre frames?
Carbon fibre is conductive, and there could be carbon fibre dust remained after they were cut. It’s a good idea to wash all carbon fibre pieces that come in the frame kit.
Carbon fibre frames often come with sharp edges that could cut electrical wires and battery strap in a crash.
Furthermore, chamfered carbon fibre edges hold their structural integrity better in a crash and reduces the chance of becoming delaminated.
More and more frame manufacturers start providing chamfered edges as a frame feature, which is a good thing. If they don’t, it’s not the end of the world as it only takes 15, 20 minutes to polish those frame edges by yourself.
Your frame will be more reliable, looks better, and feels great in your hands. :)
Where to buy the tools?
Buy file set from here:
How to file frame edges?
Get a bucket full of water, dip both the frame and the file/sandpaper in the water, place the file 45 degree against the edge, and start sanding off material.
Do the scrubbing inside water to avoid breathing in carbon fibre dust, which is extremely bad for your lung.
You can try changing the angle slightly during the process, until you get a round, smooth edge.
Here is an example of a prepared arm with rounded edges (on top) while the other unprepared arm has very sharp edges (bottom).
Don’t over do it though, you can weaken the frame strength by removing too much material.
Repeat this on both sides of the frame plates and arms.
Note that I only do this for the edges that I can touch and are exposed to crashes. E.g. on the Martian frame, I only do the outer edges marked by the red lines in the following diagram, but of course this is entirely up to you.
Glue the frame edges
It’s a common practice to apply Epoxy or CA glue (super glue) on the edges of the frame after chamfering. This is supposed to increase the frame strength against crashes and delamination further by holding the carbon fibre layers even stronger together.