I set my planer blade using a home made device.I have two small square
blocks of wood with a slot cut into them so that a steel rule fits into the slots.When placed on the outfeed table the steel rule is then at 90' to the table. Using this devise it is easy to adjust each blade so that as the planer blade is rotated under the edge of the rule the rule only moves about 3mm.Move the rule along the length of the planer blade to get a level blade.
I just use a flexible 6" steel rule placed on edge on the outfield table. Turn the knives by hand and set the blade so it just moves the rule. Do this at both ends of the knife then lock in place. Repeat for the 2nd or 3rd knife.
Only hold the rule lightly. You use it as a gauge. You don't want it to mark the knives
Jamar & Dewy.
Many thanks for the advice. The problem I have is that the blades are spring loaded in the block, the springs are quite strong and it is virtually impossible to press the blades down with one hand and ................,
hence my post for a tool.
Once I get the blade set correctly in the block I will use the method you both describe