In choosing materials. there is lots to consider:
- Functional requirments - demands on material? E.g. Hold heavy things. Outdoors/ indoors? Need to fit in with an environment look? May need certain look.
- Availability - Get the fabric in suitable form? Mainly only in standard sizes, can be very expensive. Direct effect on cost, and method of manufacture.
- Production method - Some are easier to join than others, e.g. wood can be glues, screwed, nailed, bolted, knock-down fitting. It must be suitable for intened production method. E.g. use injection moulding with plastics but not wood.
- Economics - think about size, some are expensive, but may be a good choice. Is it a one-off, batch or mass produced? Will make difference. One-off; more expensive. Mass; cheap.
Thermoplastics - Recyclable and bendy!
They are easily formed into shapes, but don't resits heat! They are easy to recycle - they're ground down, melted and re-used.
Thermoplactics and their uses
- Acetate - hard, transparent and flexible. Used for overhead projector transparencies and packaging.
- Acrylic - hard, shiny. Resists weather well. For making motorcyle helmet visors, baths, signs, etc.
- Low-density Polyethylene (LDPE) - soft,strong but lightweight. For packaging, carrier bags, washing up liquid bottels, and to laminate paper.