Forum:Materials

The printer chasis and internal supports will need to be rigid and moderately strong. Preferably it will be cheap and easy to machine/lasercut/etc. Suggested materials are as follows: (add ideas as necesary)
 * Thin Plywood (Cheap and easy to find. Comes in large panels if necesary.)
 * Acrylic (Cheap and easy to work with. Readily available, and comes in every shape and size imaginable.)
 * Extruded Plastic (as in makerbot style. A fully printable printer could make it cheaper and easier to produce. This would also lend itself to being modular, allowing different parts to be exchanged between versions, so upgrades will not require replacing large assemblies)
 * Use cheap plumbing pipe for the bar that the print head has to move on. That way sizes can be altered easily from a small A5 printer up to an A3 or bigger model. Just tried this and the first problem is because it is round in cross section the carriage turns. As a quick hack (no square bar to hand), two pipes next to one another makes it stable. Will try with something flat tonight.
 * Can cheap car timing belts be used. While thicker than usual ink printer belts, the ready availablity and range could be useful. Tried, but if not the correct size it is hard to cut and rejoin. Guitar string and a mecanno brass coupling allowed a tight adjustable cable. Brass coupling is no more than a tube of brass to allow both ends of guitar string to pass through and two screws to lock strings in place.
 * The travel block that holds the print head and moves along the main bar needs to move smoothly. Would plumbing PTFE tape on the inside make this smooth enough? If this was a split D cross section space, the split could be squeezed together with a simple nut and bolt alowing adjustment to get the grip just right. Too tight and it would stick to the bar, too loose and it would be inaccurate.
 * Can Lego, Plymobil, toy car etc rubber wheel be used to move the paper through. The large Lego wheels have balloon tyres that are fairly soft and rubbery, allowing enough grip for a single piece of paper to move through either a vertical gravity fed printer or in multiples for a flat bed printer.
 * Thin gauge aluminium can be used for slots and supports - structurally strong and easy to cut
 * Aluminium rods can be used as guides, and can be greased for a smooth ride
 * Aluminium blocks can be drilled and lubricated to give a good sliding cradle for printer heads
 * The best slide bearing material is brass on stainless steel. All the printers I have pulled apart have all had precision ground shaft with a brass collar that is held in the printhead block. I think an aluminium printhead block with a brass collar would be ideal. Also, the support is generally just a greased up piece of the frame.