There are times when you want to add a mechanical part to a model where a portion of the part hangs down below the model. If we had the ability to offset the model to a fixed Z height whereby supports are applied to provide the Z offset, then no additional mods would need to be added to the model to ‘fake’ a Z value.
It could be a simple checkbox in the positioning tool that allowed a Z value to be set and filled with the chosen support strategy.
An example of this is 3D printing a tool handle where a bolt is inserted into the print partway through the print. The bolt would drop into the opening of the partial print and then be covered by subsequent layers. The Z offset would need to be slightly larger than the length of the bolt extending below the handle model.
In this example, I want to elevate the base of the model by the ‘blue’ amount. With supports this is easy. Then, pausing at the ‘green’ layer, I can drop the bolt into the print, continue, and have a very nice handle with a threaded rod that won’t come loose!
Another example is shown in post: