As an (electronic) engineer I find many components of RepRap printers heavily oversized and therefore also overpriced. If you develop a product you should always use the components that serve the given purpose - there is no benefit from overdoing that. Using linear rails for general purpose 3D printer is such a nonsense and even belt drives are not needed, exspecially with delta printers. The forces, the speed and the load that lasts on the arms is so minimal a simple string is all it takes. Save that money and invest it in some other components that still are not mature and improove them.
There is no reason to use belts or threaded rods, linear rails on those printers, it only makes them heavy and expensive. Only if you have very special applications that - by any reason - do require this.
We have seen belts in bikes and even motorbikes, but still today these remain exotic solution. With a string you are far mor eflexible when it come sto design. You can lay it around corners and place your motor anywhere, it is cheap, it is availabe worldwide no metric-imperial hazzle. You can print out all parts for your drive (exept for the string of course). Only the installation can become a bit of a fumbling procedure.
But in the intension of the RepRap idea: Make a printer that can print out itself - Make it cheap and widely available, strings are the way to go.
I find the usage of strings one of the great innovative introductions that took place at RepRap, that point into the right direction and i have not seen anything more convincing for that (lightweight) give purpose.
Edit: Maybe one could even use a filament from a spool(depending on the material) and simply use it as string, then all parts are printable or ready to use.
There is no reason to use belts or threaded rods, linear rails on those printers, it only makes them heavy and expensive. Only if you have very special applications that - by any reason - do require this.
We have seen belts in bikes and even motorbikes, but still today these remain exotic solution. With a string you are far mor eflexible when it come sto design. You can lay it around corners and place your motor anywhere, it is cheap, it is availabe worldwide no metric-imperial hazzle. You can print out all parts for your drive (exept for the string of course). Only the installation can become a bit of a fumbling procedure.
But in the intension of the RepRap idea: Make a printer that can print out itself - Make it cheap and widely available, strings are the way to go.
I find the usage of strings one of the great innovative introductions that took place at RepRap, that point into the right direction and i have not seen anything more convincing for that (lightweight) give purpose.
Edit: Maybe one could even use a filament from a spool(depending on the material) and simply use it as string, then all parts are printable or ready to use.
