ddrescue and gddrescue also have restartable mode for failing drives, very very handy feature. I've recovered numerous otherwise unmountable Mac/Windows drives

ddrescue and gddrescue also have restartable mode for failing drives, very very handy feature. I've recovered numerous otherwise unmountable Mac/Windows drives using ddrescue, mmls, sleuthkit, and foremost. Usually I'm able to lsblk to determine the block device, rip the data partition with ddrescue and mount it loopback with mount once I use mmls to confirm the partition type. For Mac volumes that dont mount, either fsck.hfsplus or get the file to a Mac to run diskwarrior (Alsoft has been repairing HFS volumes for a couple decades). If nothing else works once you've got the raw bits saved, foremost will usually scrape something worthwhile off your image file.