You know what they say: the best time to build a time machine is 50 years ago.

I think that’s basically the movie Primer too, they’d turn the machine on, go hide in an apartment for X amount of time, then go back to the machine and emerge 5 minutes after they turned it on and just walked away.

But gravity effects time, sticking close to a planet isn’t going to be hard.

Ironically enough the first (if we ever get them) time machines are going to be a hell of a lot like modern “UFOs” are described. You couldn’t risk landing on the planet, elevation changes are what’s really a nightmare to account for. Show up and hour early and everything is a foot higher because of how fast we’re spinning.

So you’d want a space craft, because space is big and empty. And realistically it’s going to take something bigger than a telephone booth or even the 1980s embodiment of Florida on four wheels with a hood designed to do cocaine off of to house a time machine.