Robox® has a removable print bed, it simply clips in on top of the heater element. This allows us to provide a range of bed surfaces for different fused filament fabrication (FFF) or machining purposes when a different head is fitted to Robox. We are testing several materials to select one to be the standard bed for shipping with Robox, additional beds will be available that provide different performance on certain prints.
A lot of Robox users will tend to make most of their prints using PLA because it gives good results very quickly and easily with lower print temperatures and less shrinkage as it cools. ABS is much better for prototypes and items that will be used for more than display or visual checks, it is very strong and can be machined following printing, eg sanded or drilled without melting.
Our tests have shown that there are a few bed materials that have all the right properties to make an excellent all round print bed, we are testing the best way to make these beds remain flat over a range of temperatures and remain usable after a large number of prints, importantly they must be able to transfer heat into the printed parts to control shrinkage and the part must remain stuck to the surface.
Currently Glass and ThermoSurface are standing out as good options. We could supply the first FFF versions of Robox with either of these beds and it would perform very well.
We are tending to use a ThermoSurface sheet as our print bed as most of our prints these days are in ABS. The ThermoSurface bed when used in a controlled environment allows us to print objects using ABS that would often detach from the bed or warp and cause unwanted variations in the shape and finish of the printed part if we printed using a glass bed.
The perfectly flat surface of the bed is very important for many printed parts, particularly larger parts, ThermoSurface can deform much more than glass. This can effect the bottom surface of the part and the heat transfer from the heated bed underneath.
Glass on the other hand is naturally flat and extremely stable through a huge range of temperature or chemical environments. If we were only to offer printing in PLA then the glass bed would be an excellent option.
Glass is cheaper than any of the other materials we are testing, it can be simply cut to shape while other beds will require molding or other processes to work as we intend them too.
What would users want? A cheaper option that will cover the majority of their printing needs? Or a more expensive option that will allow a bigger range of materials and model shapes but which may need replacing after a certain number of prints? The various beds we make will all be available as add on or replacement items so a user can have the best properties of all of these beds. The question is which one do we include in the first package?
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