Welcome to Autodesk’s Meshmixer Forums. Share your knowledge, ask questions, and explore popular Meshmixer topics.
Showing results for 
Show  only  | Search instead for 
Did you mean: 

Separate mold (no plain cut)

Message 1 of 9
453 Views, 8 Replies

Separate mold (no plain cut)

Hi all,


I'm pretty new to MeshMixer and got a problem with separating a mould into 2 separate parts.

From a third party I receive a mesh which has a very irregular 3D shape and is 5 mm thick. From that mesh I need to make a mold, which is quite simple in Meshmaker with the offset, invert and flip normals command. That mold is going to printed on the 3D printer in PLA with 2mm wall thickness. The mold gets filled with liquid Silicone. Once hardened I need to get the silicone part out so I have to cut open the mould along the edges. This is not very easy job, I use a kind of Dremel tool handmill and an oscillating sawblade to do so. Because of the generated heat the PLA starts to melt again which is annoying and makes it all kinda messy and the edges of the silicone part gets some damage.

So what I really need is a way to separate the mold along the edges so that I can 3d print them seperatly, tape the two parts together and then pore the silicone in. But the edges are very irregular as mentioned so a plain cut will not do. Is there a way in MeshMaker to do this?? 


Thanx in advance, Mark.


Message 2 of 9
in reply to: m.van.hameren
Message 3 of 9
in reply to: hfcandrew

edit sorry for this

Message 4 of 9
in reply to: m.van.hameren

np, its a long thread.


If you get stuck just post again with your .stl attached.

Message 5 of 9
in reply to: hfcandrew

Hi hfcandrew,


I'm completely lost in that tutoral from MagWeb in your link.

This seems a bit more for the advanced MM user.

Could you give it a try??


Thanks, Mark.

Message 6 of 9
in reply to: m.van.hameren

a np, see attached. fyi didn't add the flanges, and did some flattening on the perimeter. This is not magweb's full method moreso the one from my video.

Message 7 of 9
in reply to: hfcandrew

Wow....unbelievable. Just what I wanted. Thank you so much!!


you mean this one:  ???

Message 8 of 9
in reply to: m.van.hameren

Yep. np!

Message 9 of 9

Hi there,


So we found another way of doing this in MeshMixer.


1: We import the mesh in MeshMixer;

2: Hit SELECT and switch from "brush" to "lasso" in the topbar;

3: We draw a line around the mesh where the mesh should be separated;

     this linedrawing works only in one way, if you have to rotate your mesh to keep on drawing the line, just pick it           up where you stopt and go on in the same direction otherwise you have to start all over again. Once the line               connects with the startpoint the mesh bi-colors; 

4: If the edges are to ragged you can do SELECT - MODIFY - SMOOTH BOUNDARY;

5: Then hit EDIT and SEPARATE, the object browser pops up and shows 2 parts;

6: Then hit EDIT and TRANSFORM, with dragging the arrows you can move the parts from eachother;

7: SELECT one part, hit EDIT and FLIP NORMALS;

8: Then SELECT and EXTRUDE with a negative value of your desired thickness of the mould-wall.

9: Do step 7 & 8 the same for the second part. Then you'll have two moulds which can be glued or taped together for      filling with whatever.


Please be shure that you always select the whole separated part with contol A, sometimes the mesh is inconcistent and small parts will be left out when selecting with a double mouseclick!


I hope this will help others, with a very BIG thanks to my co-worker Jim for this walkthrough.


Greetings, Mark.




Can't find what you're looking for? Ask the community or share your knowledge.

Post to forums