From time immemorial　Advance of Bow made by compositing methods in soldiers of the nomadic tribes.

Class14: Composites

Composite bow is the most valuable invention in ancient age. In old day Mongolian used its and technique of horse riding for conquering half of the world. It made from natural materials. So it requested high technical level. But its technique had been lost in world today.

This week’s assignments This week’s assignment is “Design and make a 3D mold , and produce a fiber composite part in it”. I tried to use “Nanduti Lace (Cotton thread) as fiber materials. Ñandutí is a traditional Paraguayan embroidered lace, My final project is inspired for methods. Motif Embroidered up could cut out form under fabric by starching. Therefore I considered

Nanduti laces

3D Design

First I make 3D data of using Fusion360.

I wanted 5cm hight mold for flower ball. But My lab has only mill 3cm longth for machining. Therefore I consider fitting two molds 2.5cm hight. So I designed two parts with joints.

mold’s materials

I made mold from Styrofoam. One reason is that it easy to fix lace fabric by using marking pin and thread. <img src=”http://archive.fabacademy.org/2016/fablabhamamatsu/students/188/images/c1505.png" />

Starching

I made laec hard by suseing “Tapioca”. “Tapioca”is a starch made from Cassava. Cassava is stable food in Paraguay. So In traditional methods Nanduti lace is starched by Tapioca. At Traditional Nanduti’s methods It’s used Tapioca solution 4g/100cc for Starching But I used its 8g/100cc for shading my objects. At first time I had mistake it. I try to use its solution 15g/100cc for shading.But Its too thicken to be precipitated a powders on surface. I considered 8g/100cc si best solution for shading 3D objects.

Tapioca solution need to boil until its solution be transparent. In this process Tapioca’s starch need to be gelatinized enough.

Cassava

Tapioca powder

By the way Tapioca is used with coffee and deserts in Shinzen.

Tapioca ball in Coffee

Parts 1 Flower ball

I fixed lace to mold by using threads. I referred to Yurts(mongolian tent) for ways to tie threads.

Yurts(mongolian tent)

Binding fabric like Yurt

fabric boul became hardend

Parts Flower 2 cyclic petals

At first I cut extra warp lines from I fix lace to mold by using marking pins. I putted starch only outside and center bottoms. At final I formed extra lines into a bunch as like stamens or pistils.

Cutting extra outline

starching

Results

1. Tapioca is natural aqueous coagulant. So it diffcculet to use MOLD-RELEASING AGENT. I recomend to put gouze between work and mold.

2. Tapioca low hardness coagulant. So should impregnate slightly larger to joint part.

3. When you make Tapioca solution its concentration is below 10g/cc. If over it after dryness white powder form on the sureface of work.

4. sufficiently heat Tapioca solution for denaturing β-starth to α-starth enough.

his is a file I made as a assignment.→ eagle1

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