Unanswered Tolerance on Z-Axis is off.

It is a direct result of the way we are told to assure adhesion of the first layer. I have always thought that we just do it wrong, but nobody wants to change because "that's the way we always do it" and "because it works".

You are talking about .0325 mm on Z height, that is not much but it could be significant if you are trying to mate two separate prints together.

Here is how I solved this problem for myself and still get good adhesion on the first layer. I make sure that my Z offset is used to assure the first layer is actually the height I ask for. If I want a layer of .25 mm I want every layer to be .25 mm not every layer but the first one. So I adjust the Z_Offset until I get that on layer 1. Now I need it to adhere to the bed. Every modern slicer now allows you to set the amount of plastic it extrudes for the first layer separate from the subsequent layers. Some will label it First layer width, others might call it first layer extrusion multiplier (there might be other names). Basically they all do the same thing, they adjust the actual amount of plastic the extruder is trying to push through the hotend on the first layer. Adjust in small increments until you have dialed in the proper amount of adhesion and you get the proper amount of compression on layer 1. Now you have a measurable correct Z height.

If you ask why would I go to all this trouble for just 0.325 mm? Well, if all you are printing are things you downloaded from Thingiverse or Aria statues or Pokemon, you wouldn't. But you, @PACNOR RC AEROSYSTEMS, are trying to print UAV parts. I am sure accuracy is just as important as precision. You may need to do this for each and every type of filament you use but for the most part your Z_Offset will now also remain constant and it will only be the first layer extrusion multiplier that will change.

 

Please reread what I wrote, you are not 'correcting' this in your CAD program. You still need to make models with accurate dimensions. You are asking the slicer to respect those accurate dimensions.