It took him a while…nearly 40 years, but he finally solved the problem with his sub-transit temporal confabulator. Or we can just call it a “time gate”, for you and me.
It all started as a game when he was a kid. He would build spaceships, gadgets and machines out of any sort of cardboard box he could find. He would use old wrapping paper tubes for swords and flatten boxes for his shield to slay the dragon dog that lived in the house. If it was a small box, like a shoe box, then the machine would be a model for his action figures…a miniature to experiment with and hopefully build it to scale at a later date…when his parents bought a new refrigerator perhaps.
Now he was a grown man and had been experimenting for years with these devices and he finally has figured out how to set up a time portal. A sub-transit temporal confabulator.