Are you wishing to print something hollow with no vertical seam? This can be achieved by selecting the setting "Vase Mode" in Simplify3D. With this setting activated, the printer will disregard your outline/perimeters setting and any solid parts of your model. It only print with one perimeter and no retraction, and therefore no vertical seam. It is great for thin-walled, decorative parts such as vases, planters, and small containers.
It can be selected by going into the layer tab of the Simplify3D process settings and checking the box shown below:
We would also recommend selecting additional settings of 0 top layers and 3 bottom layers found under the "Layer" tab, and the setting "Merge all outlines into a single solid model" which is found under the "Advanced" tab which will also heal additional error in your mesh.
1. Vase mode prints tend to be very thin and structurally weak. Bumping up the extrusion width will give you a slightly thicker part. The 0.4mm nozzle can safely have an extrusion width of 0.6mm. The 0.8mm nozzle can safely have an extrusion width of 1.2mm. The 0.25mm nozzle can safely have an extrusion width of 0.38mm.
2. Vase mode prints still have a seam. While the printer is continuously moving Z it is still retracting every layer. To get rid of the seam follow all the steps below (following only some of the steps may cause problems).
a. Setup the layer tab as shown above.
b. Under the G-code tab, uncheck "Allow zeroing of extrusion distances (i.e. G92 E0)".
c. Under the Scripts tab then Ending Script tab, add a line at the top that says G92 E0. Some of the most resent profiles have this already added.
d. Under the Advanced tab, uncheck "Force retraction between layers".
Other tips and tricks:
1. Vase mode works best on solid objects with gradual contours. Features like the shoulders of our Moai struggle with vase mode because they don't have enough support that would normally be provided from infill.
2. Using a larger nozzle can take a vase mode print from flimsy to functional. In re:3D's Houston HQ, most of the trash cans are printed with a 0.8mm nozzle in vase mode out of PLA which make them sturdy enough to handle every day wear and tear.
3. Printing completely clear or translucent is not possible with FDM printing, but printing in vase mode lets the parts get close. Having the single layer thickness also allows access to all the pockets that diffuse the light. A vase mode print which is then post processed with a coating like XTC 3D can make the part as translucent as possible.
4. Vase mode printing doesn't require retraction or crossing open spaces. Materials that have lots of stringing issues that normally wouldn't be able to give a good print can produce good vase mode prints.