May 5, 2016

This week's assignment is to design and to make a 3D mold (~ft2), and to produce a fiber composite part in it.
In this assignment, I decided to make a mask such as the Venetian mask.

14-1. Making molds & sheets for composites

Software: Rhinoceros (MacOSX), Adobe Illustrator CS5
3DPrinting machine: Makerbot Replicator2
Laser cutting machine: trotec speedy100
Molds: PLA, PVC sheet(W:450mm/H:450mm/D:0.5mm)
Composites: Felt (polyester 100%), Epoxy resin
1.Making molds
I pressed a felt and epoxy resin with a male mold and a female mold, and made a composite.
I made a male mold with 3D printing machine. And I used vacuum forming for the production of a female mold.(Vacuum forming is a method of molding sheets of plastic into 3D shapes using the force created by an air vacuum.)

First, I designed a male mold of a mask with Rhinoceros. I draw a mask's line based on this data. I connected those lines by "Command:Loft" and made surface.
I extruded a surface and save it as stl data for doing 3D printing.
Rhinoceros Data > mask_160507.3dm

I output it with 3D printer. (I printed it by half because this data is too big.)
- Resolution: 0.3mm
- Infill: 20%
- Number of Shells: 2
- Support & Raft: off
Next, I made a female mold with vacuum forming.
Vacuum forming is a method of molding sheets of plastic into 3D shapes using the force created by an air vacuum. In this assignment, I used PVC sheet.

A female mold was completed.

2.Making sheets for composites
Next, I designed a cut data for felt.
I used "Command:Squish" for a male mold data. (The Squish command flattens a non-developable (curved in two directions) 3-D mesh or NURBS surface into a flat 2-D pattern.) And I saved it as data of Adobe Illustrator.
I revised data using Illustrator. This time, I designed three kinds of data because I planed to make a composite with three pieces of felt.
Data > mask_160508.svg
I cut felt with a laser cutter.
- Power: 12%
- Speed: 2%
In addition, I made square parts(W:10mm/H:80mm) to join right and left of a mask together.

14-2. Creating the composite

I painted molds with a release agent.
Next, I stirred epoxy resin and a hardener well.
(The epoxy resin I used is this. > Epoxy resin & A hardener.)
Felt parts are painted with epoxy resin and pressured by rubber roller to let resin soak well.
They were laid on top of a mold.
All parts were stacked on a male mold, then I covered it with a female mold.
To glue parts together well, I put a weight on and hardened it. (I used a bag with the water as a weight.)
A bag was broke, and water leaked... I excluded a mask early to dry it.
A part of the back side failed, but I did it well!

And, I tried making another one.

- Mold: Styrofoam
- Sheets: Felt x2, Cotton cloth x1, Linen cloth x3
- Roland MDX-20
- flyingdisk_160706.3dm
- [FabAcademy2016] Week14 Composites
Please refer to this photo page for how to make.

I made a model with styrofoam and painted it with gesso.
I put cloth on the following order.
Felt x2 > Linen cloth x3 > Cotton cloth
It stiffened! But styrofoam and gesso has attached to its backside...