ZBrushCentral

What do I need to know for Printing?

ZBrush Usage Questions
#1

Hey Zbrush users. I’m so new to using this software and i’m trying to learn as much can for my company. I’ve gotten pretty handy on sculpting meshes and using multiple subtools, but I have some questions as to what I need to know for 3d printing.

1.) does it matter that I’m using subtools or do I need to merge them.

2.) Is it necessary or possible to create one mesh from multiple subtools?(example: head, glasses and shades merged from multiple subtools can be sculpted on but I don’t know how to combine them into one mesh.(I hope this isn’t a stupid question.)

3.) What is the recommended ploycount needed to print?

4.) How can I define the physical size of my mesh?

5.) Is it possible to print a hallow figure?

I’m only using Zb4 so i’m doing everything from scratch. I also watched this tutorial (http://www.pixologic.com/zclassroom/homeroom/tutorial.php?lesson=jeff) But I just wanted some more info.

Please Help.

#2

hi i am i no way an expert on this since i mostly use cnc milling that really uses slightly different rules but here is some things i have come across for the regular printing methods

  1. you can usually have multiple subtools but its probably best to merge them so you can export it easier without any problems the important part is that each part is watertight

  2. the new dynamesh feature in 4r2 would work great for merging every subtool so it would be a single solid mesh

  3. the polycount is really dependent on the printing service you use but a good thing that i usually do is to try and size it up on the monitor to the same size as the intended print and see how much of the faceting i notice no point in having details smaller than the machine can reproduce

  4. the 3d print exporter/stl has a feature for sizing the mesh just press the update size ratios then type in one of the fields how big you want it to be in that direction and the rest will follow before pressing the stl binary button to export.

  5. hollow figures can be printed but you need check what the minimum wall thickness the machine can handle and make it so it has a hole some where to allow the internal powder/liquid/whatever it is escape after printing as for how to make the mesh like that there is a section on that in the whats new pdf in 4r2

i hope that this helps some and good luck on any future printing.

#3

as they came

1.) does it matter that I’m using subtools or do I need to merge them.
you do need to merge them, the whole model needs to be a continuous watertight shell.

2.) Is it necessary or possible to create one mesh from multiple subtools?(example: head, glasses and shades merged from multiple subtools can be sculpted on but I don’t know how to combine them into one mesh.(I hope this isn’t a stupid question.)
Im not sure what you mean, but, you can use sub tools and separate meshes ,as long as at the end they are all merged.

3.) What is the recommended ploycount needed to print?
on average around 300k polys, most printers dont use bumpmaps, so all detail is carried on the mesh, use decimation master to reduce your mesh sub tool by subtool until you have a good count and still have a good level of detail, then merge them all.

4.) How can I define the physical size of my mesh?
on export you set the height using the 3d print exporter. I use a reference stick on my figures, it sits next to the model as a subtool, its always the height from eye to base of feet, that way I know if the stick is the right length it will be the right size. Zbrush dosent do sizes well, so its not easy, this is a work around.

5.) Is it possible to print a hallow figure?
yes, but like the guy above said, you must make sure the wall is thick enough, usually 1mm but often more, and there must be 2 holes somewhere in the mesh big enough for the support or residue material to escape, maybe under each foot, one for material to come out one for air to get in.

other things to note:
there is a free mesh checking software called nettfab. use it to check the integrity of your mesh. it wont be printable as exported direct from zbrush, there will be inverted normals, bad edges, triangles that need stitching and maybe even holes to fill. dont panic… you can use a service offered by materialise http://stlfix.com/stlfix_ENG.html if its a simple fix it will be free, usually takes 12 hours to get it back to you. if it requires more they will quote for the fix.

if you get stuck send me a personal message and Ill help, I get models printed every week, so have a good idea where to help out, or who can help if I cant.

#4

just send your model to moddler.com - as long as it’s watertight they can print it. John’s great and according to the site polygon count is not an issue.

#5

Thanks everyone for answering so fast! I found that the Netfab has an Iphone app that could view .stl files which is AWESOME!!! That site is a bit difficult to access, but I know that the company i’m printing threw could alter what needs to be alter in terms of holes. And i’m really hoping I get this Dynamesh Upgrade so I could fix these triangles.

Thanks so much everyone!!