{ Fab Academy 2015 : Koichi Shiraishi }

{ Home } { Final project } { Class } { Fab Academy }

- Week 12: Composites -

Weekly Assignment

1: Concept

I tried to make “Taiyaki” by FRP. Challenging point is using sponge within layer.

About "Taiyaki"

“Teriyaki” is a japanese sweets what a fish‐shaped pancake filled with bean jam. It bakes with a mould imitated fish.

2: Making test piece

I used a epoxy resin in this time.
To scale a hardener with extreme care.
I apply a wax for easing form removal.
To use a brush to apply a resin.


1: sponge(urethane foam)

it takes many resin. Hardening has no problem.

2: Sponge(melamine)

Almost the same results of urethane foam. It turned yellow little bit.

3: Glass cloth

I check strength three case.(1 ply to 3 ply) I decided 2 ply in this case.

3: Scaning and Modeling

To scan a “teriyaki”. and print.
To build a frame by LEGO lest a moulds slip out of place.

Printed file

4: layup

To apply a resin to mould’s surface.
To ply clothes, and then ply a sponge.
To engage tow parts with extreme care, and the vacuum pack a mould.
Hardening whole night, after then I demold a model.


This methods is not good. Casting is better than composites when a model is thickly.
Using 3D printed mould is hard to demold. Because a resin infiltrate mould.
Consequently, My “Taiyaki” came off a surface.

Second challenge

I tried to make molds for a final project part(lamp hood) by machinable wax. However It was not enough to form a block. Therefore I tried to mill a 3D printed mold coated with thin wax.

As a first process, I made a mold for mold by 3D printer. After the finished printing, I coated a 3D model with wax. The wax thickness target was about 3mm.

1,Milled the complex mold

I used a “MDX-40A” to mill the complex mold with “SRP player.” The working process was only finishing. (I did not appended a Roughing process.)

ToolFeed speedSpindle speedMachining time
R1.5mm ball endmill(2 flute)1200mm/min5000rpmabout 8h/part

Milling files
Mold stl(positive)
Mold stl(negative)


he result had minor faults. The mold bare a 3D model part. Because I failed to set a origin. I decided to use it covered with parting agent.

2,Laid up a FRP

I use a unsaturated polyester with glass cloth on negative mold. (2 ply) I made a divide surface program by grasshopper. After baked line I cut glass clothes by laser was set following parameters.

Laser typePowerSpeedHzpasses
Cutting CO2 laser701.510001

trotec speedy 100 flexx CO2 laser 60W

Divide surface code

The resin hardened quick. Because the working day was too hot temperature. Therefore I had to work without delay. I impregnated a enough resin. After then I covered by positive mold.


I broke a mold. Because baring parts clung a FRP model. I think a ABS was melted by binder of resin.


It is very smoothly surface! It mixed several air. However It was not big problem.

4,Coated by a poly putty,sanded a model

I coated by a polyester putty, after several hours I sanded it. I did the process again to again.