Introduction: Make Your Own Solar 250 Projector Cassettes

Picture of Make Your Own Solar 250 Projector Cassettes

About a year ago, I picked up a Solar 250 Projector cheap at a pawn shop. As these legendary projectors are becoming rare as hens teeth these days (especially in Australia), I found it really hard to find accessories for it. I have seen these being used at some festivals and love the effects they create so have been obsessed with them since. I decided I would have a go at making my own effects to save money on buying expensive new cassettes from the UK and also for the challenge! Once you start getting your head around how these patterns work, you too will become obcessed with experimenting and customizing them : ) 

I would like to quickly add now that using a laser printer to print the patterns worked well but not as good as it could be! The colours look a little faded when projected on a wall but still looks very cool and gives you a great point to start improving from! There is plenty of room for improvement on this project so please send through your ideas or add to mine! This has been awesome fun! 

So heres how I did it....

Step 1: Understanding How the Cassettes Work

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For those new to Optikinetics, it might be a good idea to read this to get an understanding. I will do my best to explain the concept. See here for more detailed info on Opti - the company behind the Solar 250 Projector: (its an intersting read for VJs and psychedelic enthusiasts alike) My custom cassette can be used with a proper cassette rotator or my next instructable will show you how to customize a wheel rotator into a cassette rotator.

The cassettes have the following components:

- A static image (which is still, does not move)
- A moving or turning image.

If you take one transparent "star burst" image for example and make a duplicate of it, place one on top of the other but slightly off set the centre of the 2 images, suddenly you get the "moire affect" (see image). Move one of the images around slowly on top of the other and you start getting 3D type effects going on. Very interesting illusion.

Imagine then projecting that hundreds of times larger onto a large wall, trees, stage back drop etc.

That is what this project is about! :) Enjoy

Step 2: What You Will Need...

Assuming you already have a Solar 250 type projector and 1 or 2 rotators you will also need...

• 60mm PVC pipe (any length, you will only need about 50mm for each cassette)
• Transpareny Film (I used overhead projector film found at Officeworks) 
• Good laser printer – for printing your patterns onto the transparency film
• Strong glue – plumbing/pvc glue would be best but not necessary
• Sand Paper – various grades but some fine grit for finishing is required.
• A vice is handy for this!
• A tool to cut the pipe as straight as possible – I used “The Renovator” (as seen on TV ). A small band saw would be perfect if you have one.

Step 3: Method:

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•Cut 3 lengths of about 12mm each off the end of the PVC pipe so you have 3 x 12mm wide rings. Sand them back and tidy them up so the edges are straight and smooth.

• Cut 1 ring as seen in the above picture. You then want to estimate and shorten the diametre of the cut ring so that it fits tightly into the main uncut ring. Throw the cut ring into a pot of boiling water for a few seconds as this softens it up and makes it easier to shape and fit into the main ring. Allow it to cool in place because when the PVC cools, it trys to spring back to its original shape. Having it inside the main ring as it cools restricts is expansion. : ) (See next step for pic of this)

Step 4:

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• Once you have the cut ring fitting tightly inside the uncut ring, glue it inso that it is half sticking out as per the picture. Once the glue is dry, you will cut off the excess from the inner ring resulting in the main uncut ring having a nice edge/ridge inside it. (See pic above) This has now formed the “turning” part of the cassette. 

Later, you will cut your circle patterns out from the transparent film and one will sit inside this part resting on that ridge. Make sure the ridge is fairly smooth so there is minimal friction when the device is turning! Sand off the excess glue etc. 

Step 5:

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• Take the 3rd ring and cut it like you did the second ring. This one has to also fit inside the larger uncut ring but needs to be able to turn freely inside it but not be able to move up and down! I estimated and cut the ring to size, placed the cut piece in boiling water till soft (20 seconds or so) pulled it out and sat it in the main uncut ring to cool. I used a tiy spacer between the rings so that when the hot/soft ring was cooling/expanding, it left a tiny gap between them allowing the smaller ring to turn freely inside the larger ring with minimal friction.

• Once the new inner ring has cooled, glue the cut closed to complete the circle again.

• I then cut some little “wings” to glue onto the sides flush with the top. These will be used to attach the inner ring to the rotator. (This part is probably confusing you? Because the original cassettes require a specialized cassette rotator : | I have come up with an idea to turn one of my several wheel rotators into a cassette rotator. See Here

• Sand back all the glued parts so they are smooth and do not affect the turning action of the cassette. You can paint your cassette any colour you like to tidy it up.

You have now created the static part of the cassette!

Step 6: Now You Are Ready to Find or Design Your Patterns!

Picture of Now You Are Ready to Find or Design Your Patterns!

I found my patterns from Google Images searching for “Moire Patterns” however through experiementing, I have now discovered that you can create your own awesome designs in Gimp (free Photoshop alternative). I am not going to go into too much detail here but I used gimp for creating patterns with transparency, messing around with colours etc and then tested my patterns using Paint.NET. Paint.NET allows you to place one image on top of another and turn only one of the images so you can see how it will look and work out which patterns work together and which dont. Awesome!!! (and time consuming

In MS Word, use the shape tool and create a circle that is 50mm in diametre. Print it out on A4 paper then measure with a ruler to see if it is coming out to scale. If not, adjust the size of your circle in MS Word accordingly. Test print. Once you get the circle shape correct give or take 1mm, start importing your patterns and resize them to the size of the circle. You should be able to fit 3 patterns wide and about 4 down. Once done print onto your transparent sheets. I did mine on the laser jet printer at work. Came out really well. The colours look slightly faded but not too bad for my first shot!