Deadline Hollywood has a great interview with Elmore Leonard that's a must read. Most of the talk is about screenwriting, his books that went to film (and his thoughts on them), but at the end there's a great tidbit on how he writes.
10 to 6, every day.
Output is 3-4 handwritten pages. No word processor.
He takes his handwritten pages and types them up on his typewriter to get his draft.