EDIT: Well, it's not solved, but I abandoned the approach.
That's a video of my old Canon typewriter, which I'm turning into a plotter. The thing is, I'm going to reuse almost everything. The stepper motors for horizontal and vertical movement. And this solenoid for pen up pen down activity. The trick is that when the solenoid is activated, the stepper motor rolls the paper cylinder. When the solenoid is passive, a clutch switches the transmission and the same stepper motor performs a movement, which has to do with the correction tape of the typewriter. Since I won't be using any correction tape, I'm going to use that movement for the pen up pen down.
My question is, will 5 W be too much for this solenoid. I need the solenoid to be activated most of the time, because it transfers the movement to the paper roll. Only on pen down or pen up movement the solenoid is passive. The solenoid will use 18 V, and it takes some 240 mA with that voltage. That would be some 4.5 W. In the video you see how the solenoid is mounted. Is there a chance that the metal plate will dissipate enough heat?
If it is too much, I need to glue the clutch and figure out another way to operate the pen up pen down.