A task that involves design and laser-cutting fun for some cool fridge magnets.

Supplies

Squared paper

6mm Plywood of about A4 size or similar wood

1mm or similar magnetic sheet

Step 1: Step 1: Draw Out Designs on Paper

To start my project I drew out the design of the original Space invaders on squared paper so that when putting them into CAD I knew where each pixel was. I did this as some pixels where hanging and wouldn't have cut properly, so had to amend the design so these would overlap and not be cut off.

Step 2: Step 2 : Draw the Design in Solidworks

For creating the sketches for the .DXF I used solid-works mainly due to my uni providing the education version, you could also use auto cad or a similar program. I put screen captures of me creating the designs in solid works in this video. My method for doing this was starting with a centre line and then drawing the left hand side of the design, and then using the smart dimension tool to make the size of one pixel 5mm, before mirroring the design on the centre line. One tip is too make sure you don't forget the eyes!

Each of the space invader designs once completed was then saved as a .DXF with the centre line removed before I then imported them into AutoCad (this was the point when a fellow student told me that AutoCAD is free for students) and I had to remove the solid-works annoying for education use only (yes this is educational) logo and arrange them on to one sheet and save as a .DXF for the laser-cut.

I've included pictures of the design with dimensions to follow if you want to make your own or I've also attached the final .DXF I used for the laser-Cut (spacesheet.dxf).

spacesheet.dxf
Download

Step 3: Step 3 : Laser-Cut

I used the university laser-cutter which are quite simple to set up, they use a program called lasercut 5.3 which once open imported my dxf file and then positioned it in the top right corner.

Then i made the eyes of the design a different colour(red) and then made sure this colour was cut out first, or they might end up with wonky eyes. I then set the speed of the laser-cut to 10 and power to 60, this is the setting for 6 mm plywood on this machine but that might differ on yours so always check with a manual or ask the technician.

I then uploaded the design to the machine and then made sure the laser was inline with the acrylic tool, then pressed test to make sure the design would fit onto the wood size I had about A4 size then i closed the lid and pressed start and watched it go.

Once it was done I then waited 30 secs for the fumes to clear before collecting all the pieces even the eyes and then cleaning the machine to avoid and unhappy technician.

Step 4: Step 4 : Adding the Magnetic Strip

For this part all you need to do is cut some magnetic sheet to size and glue it the wooden pieces making sure you glue the right side down, I tested this with a pair of scissors.

The reason to keep all the pieces is that the 2 pixel size eyes I used for the ammo from the ship.

The glue used was clear UHU and i them waited overnight for it to dry.

Step 5: Step 5: Fridge Time

Once the glue is dry simply add to your fridge!

So originally I designed these with cutting them out of the magnetic sheet as magnetic sheet with the right setting will "Cut beautifully" but due to me not knowing exactly what was in the magnetic sheet and the workshop technicians advising against cutting anything remotely PVC in particular the C for Chloride. So I ended up using some scrap wood I had left from building a robot. It would be great to see if anyone dares to laser cut magnetic sheet in the comments/ has the right laser cutter for the task.