so id like to check the fit of my BT30 tools in my spindle

i have prussian blue (the non-drying kind, meant for this)

i smeared some on the BT30 tool taper, then put it in the spindle.

then i took it out. i could see a "pattern" that looked like if you dab your finger in butter then tap it on a table, when you pick your finger up, you end up leaving that "mark" of butter on the table with that certain shape..the taper had it evenly almost all over

but how does this mean anything?

if i put too much blue, then it will show that pattern no matter what right? because there will always be enough to bridge the spindle and the tool

if i put too little blue...well i guess you cant put too little. the less the better i think?

but if it all depends on how much blue i put on, then we have a problem because im just smearing it on..and i cant control if its 5 thou or 0.5 thou thick can i ?

or am i doing this all wrong?