For items with flat tops but not-so-flat bottoms, we use shims like those used in installing windows and doors for the less-challenging situations and pieces of wood or plastic for the more challenging, unleveled bottoms. You can actually use a combination of the two and finetune the shims to meet the needs of your particular item. It is important to keep a level handy to check your item for evenness in both directions in order to ensure the best prints.
For odd-shaped items like those with semi-cylindrical or semi-conical bottoms, we often revert to our childhood and use Playdoh to build up the non-flat areas to allow the printable surface to be flat and parallel to the print head’s path of travel.
Now, what about the “lollipop conundrum”? The challenge is to get the “head of the lollipop” out of the path of the print head. How is this done? Simply position the item on the bed with the “head” off the front so that it is out of the path of the print head. If need be, you can use Playdoh to secure the item as described above.
-Don Copeland, ColDesi