Printed in 75% scale with Brim in 8 hours and 15 minutes.
Most important thing is to secure the model to the plate.
Without a heated bed i used "Scotch Blue Tape" to cover the bed.
I printed it with a Brim, which I also taped to the bed. With that, the model couldn't move anymore.
After 50%, I paused the print and taped the sites of the model to the bed too. This has prevented it from wobbling.