When doing multiple knives of different soak times, like 1095 (5-10 minute soak) and 1080 ( 1-2 minute soak) pull the shortest time blades first. If doing a batch of knives of the same time, pull the first blade when the soak time is up. Within reason the others will be fine with the additional time in the oven. Make sure the oven has returned to the target temperature before pulling the next blade.
As for quenching multiple blades, it largely depends on two things Quenchant type and quenchant volume. I personally feel that 2 gallons is the minimum quenchant volumne for quenching one blade, and 3 to 5 gallons in needed to quench more than one blade. If using Parks #50, you use it at room temperature. It can rise to 100°F with no loss of quenchant speed. If using AAA or similar oil, you have to heat it to 120-130°F before quenching. The best solution when doing multiple blades with this type quenchants is start at 115°F and let the temperature rise as you quench the blades. The oil will need to be cooled down if it reaches 140°F. One simple way to do that is freeze a quart milk bottle full of water and have a string tied around the neck. If the oil gets too warm, take the bottle ( wipe off any condensation or frost) and dunk it in the tank a bit to drop the temperature.
In most cases, a fan blowing across the quench tank will help keep the temperature within range. You have a couple minutes between quenches anyway as the oven rebounds to the target.
TIP:
Set up a set of quench plates. These are thick aluminum plates (usually 3-4" wide, 1.5-2" thick, and 12-18" long) that you clamp a blade between. Foe stainless steel and other air quench steels (like A-2) the blade is put between the plates right after being removed from the oven. For oil quenched blades, after about 8 seconds in the oil, clamp the blade in the plates to prevent or lessen warp and twist. If doing multiple blades, when the next blade is quenched, pull the one out of the plates and put the new one in.
