Oh, now I got it! thanks
Abe can make a RUN-JUMP movement. It means that Abe can grab a ledge if he is running and you prees the -JUMP- key (not the UP key).
Screen R1P15C11
So, what you have to do is to bring Abe to left side of the upper meat saw.
Pay attention to the meat saw timing, and when it is safe, run right and press the JUMP key.
If you do it right, Abe will grab the ledge that seemed to be unreachable before.
Reminder: Its easier to use a RUNJUMP to grab and go up ledges than using the hoist.