Paper-based technology
Practical Action
Wheeled items
Thin card, thick paper, and sometimes carton card is used to make wheel assemblies consisting
of a bearing in which an axle with fitted wheels can rotate or a single wheel between two bearings,
and also to make steering systems for some items for people with disabilities. Bearings are usually
attached under a chassis. Wheeled items include toy cars and carts for pre-school, and much
sturdier items for people with disabilities including push chairs with insertable wheel systems,
floor rafts, push-along tricycles, self-propelling trolleys, and low-level wheelchairs. All these are
for clinical or home use rather than for rough use outside, but they are quite durable and easy to
repair.
Making a child‖s chair
This chair is a Utility model, using Approach II: two
vertical boards joined by a pattern of rails which
support a seatboard. It is not a difficult model, but
making it involves a number of operations. It is the
prototype of all Approach II Utility models. Some
preliminary knowledge is necessary, and as the chair
will be made in stages this knowledge will be
provided before the actual working instructions,
stage by stage.
Preparatory stage
Making the templates and the components
First: Get a clear idea of the job. Study the
illustration on page 20. Decide the exact size and
shape of the chair you want to make, and cut card
templates for the three boards. On the sideboard
templates mark where the holes for the tubes (rails)
will be, allowing for the top of the seatboard to
project slightly above the sideboards.
You need to know:
What grain/corrugation direction is. (See
earlier)
Figure 2: Laminating - work quickly,
race-the-stretch
How to make paste from plain flour. Follow
these instructions exactly: Mix a heaped
tablespoonful of plain flour in a little cold water, stirring until it is the consistency of
cream and there are no lumps. Pour in 500ml of boiling water, stirring vigorously and
continuing to stir for some time.
How to prepare your work surface. Spread a square of plastic on your table and place
either on it or nearby the following: a container of paste; a container of water; a sharp
knife; a plastic bag of pre-pasted strong paper (such as from a potato bag); some
newspaper; cutting and pressing boards; a rough stone; and weights.
How to laminate corrugated card to make boards. Decide from the thickness of the card
that you have how many layers will be needed to make a board about 150mm thick. Use
a template to cut each piece of card to the right sizes with grain direction alternating with
each piece. Place one card on your table plastic. Paste it generously all over. Place the
next card on it, with grain alternated. Paste that one. Continue until the board is over
150mm thick, with the template as the top layer. Wrap in a sheet of newspaper. Press it
first by treading all over it, then leave it pressed under a weighted board to dry.
How to roll tubes of thin card for the chair. Prepare rectangles of card which are about
40mm longer (along the grain) than the width of the seatboard. Find a suitable roller
(such as a broomstick). Lay the card on the table plastic, with its grain parallel to the
table edge. Smear paste thinly over the card and onto the roller. Place the roller along the
front edge of the card. Roll the card tightly onto it, and continue rolling it to stick the end
edge down. Seal it down with pasted paper and pull it off the roller without delay.
Get to work:
Laminate the boards, roll the tubes, and let them all dry.
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