# Making a Kinemat

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## Introduction: Making a Kinemat

The idea was to create a curve-dawing machine called Kinemat described in Ivan Moscovich's book "Leonardo's Mirror and Other Problems".  According to the book, 'Though seemingly simple, this device can be used to draw a practically endless number number of aesthetic families of complex curves. Mathematically. these curves have been named "tri-circuclar sextrics", which means they can be described by equations containing terms up to x^6'

The curves produced from Kinemat are inherently aesthetic and quite complex. They contain no true circular arcs, nor true straight lines.
Since I was a stranger to wood working, I decided to make the kinemat out of Styrofoam (the ones which are used for packaging).

## Step 1: Materials Required

No prep works are needed for this instructable.
You will need:
-Craft Glue for sticking paper to styrofoam
-Ruler
-Pencil
-Incense sticks - probably 2 or more
-Paper knife and candle
-Ivory sheet or any stiff and durable paper
-Battery
Needless to say, candles, knives should be used carefully.

## Step 2: Blueprints

The kinemat will consist of 4 parts:
-Crank Arm and Rocker Arm (both are basically the one and same, just different names)
-Coupler Disk
-Drawing Board

Each arm will have 5 holes
The disk will have 18 big holes and 103 smaller ones.
The drawing board will have 24 holes along its perimeter.
Other than the smaller holes, all the others are of the same radii (0.7 cm).

Info about various parts (first see the blueprints to get a better idea):
1. Coupler Disk - The normal holes are arranged in two logarithmic spirals. The smaller ones are in alternate numbers distributed between 12 radii of the disk.  Diameter of disk is 22 cm
2. Arm - The arms are two in number. The dimensions are 18.125 cm x 3.5 cm. The distance between each holes is 2.1 cm. The distance between the first hole and the perimeter of the arm is 1.05 cm.
3. Drawing Board - The dimensions are 29 cm x 29 cm. The width of the narrow passage is 3.5 cm and distance between each hole is 2.1 cm. (separate drawing is not given refer to the scanned documents for details)

In addition you will also need a sturdy cylinder (discussed in later steps).
.psd Pictures of board and arm may not have correct measurements. Please verify using the scanned paper (sorry for the mess)

## Step 3: Cutting the Basic Shapes

To make the shapes of the arms ,disk and board draw their outlines on the Styrofoam.
For this step, you can also print out or copy the blueprints on plain paper, stick them on the Styrofoam and use the perimeter as the outlines (this is more effective and the paper will have to be eventually glued to the paper). However, the board has to be drawn manually. A picture of this is given.
NOTE: If you are sticking the paper, it would be better if you cut out the all the holes. The bigger ones can be cut out with a knife. The smaller ones can be made by just piercing a ball point pen through it.

Heat the knife on the candle and cut along spare styrofoam to know the required hotness of the knife to cut precisely and smoothly.
Then, using the same procedure, cut out the shapes from the styrofoam.

## Step 4: Making the Holes

Light an incense stick. To familiarise yourself with the required timings, try burning a hole of the required diameter on stray styrofoam. Use this procedure to create the holes on the board, circle, and arms. For the smaller holes in the disk, pierce ball point pen leads at the required points.

Be careful. If, by mistake you remove an extra chunk, you could risk starting over again.

## Step 5: Creating the Pins

To connect the arms and disk and arms and board, we need two pairs of pins.

To make these pins, remove the outer zinc case of 4 batteries to make 4 pins (these have a diameter equal to almost 1.4 cm). Also, to ensure that these can pass through the holes, gently pass them through each of the holes.

## Step 6: Assemble

Before assembling, paste a cardboard or ivory sheet in the central 22*22 square of the board so that pencil or lead can be traced.
If you haven't already made the small holes in the circle, do it now.
For the assembling part, refer to the video.

Sometimes, the battery can also obstruct the way. Remove the pin, rotate the arm a little bit and put the pin inside again. You should probably figure this out yourselves.

## Step 7: Draw!

See the video for instructions.
The rar files conatins the curves drawn by some kids and coloured by them.

Note: 1. Move the machinery slowly and smoothly.
2. In case of obstruction, look for the cause and try to remedy it, like in the video ( like the arm sometimes get stuck)
3. the curve produced will be fully smooth since they are not so accurate. You can yourself guess those curves and finish them.
4. You can also colour the curves.

Improve upon this idea and be sure to show me your own hand-made curves.

Suggestions are greatly appreciated since this is my fisrt instructable

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