this is a really simple hacksaw mechanism designed in SolidWorks for a first-year machinery students project.
I used a servo motor with a controller, it's a 360-degree rotating servo
the SolidWorks files are also uploaded so you can go and redesign the base, for example, to put whatever motor you like,
the blade is just regular blade from a hand saw.
small note: you could use a little bit of lubrication to make the saw move as it should.