3D Printing for Paper Pulp Molds

[TinyRhino 0]

Greetings. First Post.

I've gotten an Ultimaker at the school where I teach and it's working well.

I want to be able to produce 3d printed paper pulp molds with the Ultimaker similar to the ones described in this Stratasys article:

"3D Printing for Paper Pulp Molds"

http://www.stratasys.com/solutions/additive-manufacturing/tooling/molded-fiber

Making this kind of paper pulp mold will require variation in porosity of a print. I need to make the top surface with slight gaps to let water be drawn through but not the pulp.

The key step in what the Stratasys does seems to be this: "Designers can easily maximize air flow and minimize clogging by altering the raster gaps in the FDM toolpath."

I'm not sure what setting to use in Cura to alter something equivalent to the "raster density". The way I imagine it, I would build up a normal support structure and then sort of crosshatch the top layer leaving a small gap between each filament pass. I would end up with a fine screen that could let water through but not paper pulp fibers. By adjusting the gaps I could find the optimum screen porosity for the process.

Any ideas or tips?

Regards,

Josh

[Nicolinux 288]

Ok, here is an idea. Access the expert settings in Cura and untick "solid infill top/bottom". Then you can set the infill to controll the raster density.

[gr5 2,070]

I was going to say the same thing as nicolinux. You might want to print the screen in two parts if you want it to be thick - not sure. Then glue the 2 parts together (the support with low infill % and the top with very high infill %).

Edited September 3, 2015 by Guest

[gr5 2,070]

Looking at the article - if you want the walls to be porous also, then I would also set "shell width" to zero. I think that would work quite well. I've done that before for other specialty prints.

[SandervG 1,519]

Very interesting, curious to see where this is headed.

Could you post your progress here @TinyRhino?

[cloakfiend 994]

If you want to make a paper pressure mold then some skills in 3d will go a long way to make pretty much anything you want. In a 3D program you would make the model you want to create in paper. Then create a big object that covers your main one entirely with a really high polycount as we aren't really interested polygon edge flow or polys at all other than you need enough to create a halt decent boolean (as booleans are notoriously bad in terms of polymodelling and usually need lot of cleanup afterwards) at all. then you would make a boolean of the object and subtract it from the big 'mold'. then you would simply split the mold and boolean a ton of holes through the centre of the mold to get your pourous holes. you don't need holes in the sides, there just there to let the water out. kinda like a garlic presser. Then make a hinge and voila! done!

But thats just how i would do it. Quick and dirty. If you have your object, you could probably knock the molds out in about 15-20 mins of modelling time. maybe a touch longer if you are trying to be precise, but there is no reason to be precise if you are making paper cast molds as you wont notice the difference in the end.

edit..i just looked at that page, and it seems like you want the holes in the edges. still my method would work, but the holes would simply be shifted to the side.

Edited September 6, 2015 by Guest

[CrazyDan 0]

Josh --

How did your project turn out? Were you able to create a pulp molding tool? We are trying to create a tools for molding cafeteria trays from pulp, and wondered if the technique of setting the top and bottom thickness to zero in Cura was successful.