Snow machine prototype - part 2

This post reports on our second practical session designing and developing a prototype of a theatrical snow machine. (The write-up of the first session can be read here).

Make more holes

In our first session we decided that we would use slots of 1cm x 5cm with spaces between them of about 4cm along the length and 6cm across the width of the cloth. Our first task, then, was to cut slots along the whole length of our cloth and across about half of its width. This turned out to be quite time-consuming and should we ever want to make a full scale device, or several in battery, a faster way of doing this would be a big help.

Block the sides

Our first experiments showed us that a lot of material escapes off either end of the cradle and we decided we would need some kind of elastic material cut to roughly the shape of the profile of the cradle in order to close the ends. After some thought, we came up with an off the shelf, or rather "off the peg" solution (Size L):

We looked at a number of designs, and were quite taken by one leopard-skin print, but in the end went for a more theatrical black.

we cut off the front an kept the back.

and sewed the pieces into the gaps at either end of the trough.

From hand-held device to something that can be suspended and remotely operated.

Our idea was to operate the cradle, using various lengths of string which will run along the scenery bar, then down to the wings off stage. We would simply lift the cradle by pulling the string and then allow gravity to return it to its starting position.

These cross sections show how we would operate the cradle.

The first step was to make a simple wooden structure which could both keep one side of the cradle still and also allow us to place 2 eyelets for the string to run through.

 Here you can see it without the cradle in place.

And here with the cradle attached. This photo shows the resting position, with the slots fully raised.

We used a readily avilable polyester chord which is qute shiny and generates minimal friction as it passes through the eyelets. In these videos you can see how it works:

A complete success! The cradle can be raised and lowered smoothly.

What's next?

• Finish stitching the sides.
• Work on improvements to the polythene snowflakes and the method of making them.

Hopefully in one more session and blogpost we will have a prototype and proof of concept. Watch this space...