I keep on meaning to create a post with this timing information in:
These are estimates of how long a set of reps takes, followed by the ideal rest periods between sets.
The chances are that 1-5 reps takes 0-20 seconds , with 1-2 reps needing 300 to 240 seconds rest and 3-5 reps needing 240-180 seconds to recover
If you are doing 6-8 reps, the chances are it takes 20-40 seconds and you need rest of 180-120 seconds between sets.
If you are doing 9-12 reps the chances are it takes 40-70 seconds and you need to leave 120-90 seconds
If you do 13-20+ reps, chances are it takes 50-120 seconds and your rest period could be 90-10 seconds.
Rest periods can really support or screw your training