I'm taking an Arduino, a breadboard, wires and a handfull of electronic parts in an airplane from Europe to Asia.
Should I expect problems with security? I'm afraid security will think it's a bomb. To be honoust, I would be surprised if they did not have a closer look at it.
Should/can I take the Arduino and parts in handbagage?
John
There were a few other threads about this in the past and I believe the general consensus was that you won't have a problem. But be prepared to either ship it or leave it behind.
And as far as x-ray (or whatever they use now) machines, it will look no different than a cell phone, computer, or some other electronic toy.
I have taken a 2.4GHz transmitter in carry on and they never said boo, they did however want to look in my bag because it had more than the usual amount of network cables 
and they took my electrical tape, bastards!
I'd imagine that in your hold luggage, split into bags of components won't raise any eyebrows. Assembled and sitting next to your old alarm clock along with a bundle of magic markers might trigger alarms.
I think it all depends on where you are in the world and where you are going to. It also helps if you don't have a beard and munch a bacon sarny as you go.
It also helps if you don't have a beard and munch a bacon sarny as you go.
Did you get caught out by that then? 
Yes but the bacon saved my bacon.