What is IDEX 3D printing all about?

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While single extruder performance with BCN3D Epsilon W50 was not fast (around 20% slower than a Prusa MK3) its printing volume is significantly larger. So we put that to some u
se, packing several large parts into the print bed. 

If some of these parts are similar (either equal or mirrored) the use of IDEX can help here. So what is IDEX? IDEX is the acronym of independent dual extruders, which may not explain much yet. 

These are 3d printers that have two print heads instead of one. Each one of these two print heads has its own extruder that can be operated independently from the other. This is quite a different thing than these other printers that can handle different filaments in the sense that here two extruders can operate at the same time, so two hotends can be pushing plastic onto the bed to create two different parts.

Not very different as if you were able to write or draw with a pen on each one of your hands, but with a little catch here: although we can draw two lines at the same time, the printer cannot place them at two independent locations. What it can do, instead, is to place them at a common Y-axis location and each one of the two print heads can be placed at a different location along the X-axis. But you have to be careful so the two heads do not crash into each other.

A simple way to avoid crashes is to split the print bed into two different domains of half the distance of the original bed width. This way each head can only move along its now smaller domain without the risk of crashing into the other. So this enables the printer to print two (or more) similar parts on one half of the bed using one of the print heads, while the other print head moves in the second half of the bed replicating the same objects at the same time.

This means that if a part takes 100% of the time to be printed you can print two parts in exactly the same amount of time, which looks as if each part only required 50% of the time to be printed. And you are not restricted to creating copies of a part. A second idea is to print parts that are the mirror image of the other, again, leading to a significant print-time saving. For example, while I mentioned that the W50 is slower than the MK3, if you need to print two parts (and in our case, we need many copies of a model), the W50 is actually faster as it can print two parts in the same time it prints a single one (thanks to the IDEX magic) so two parts require 120% of the time it will require a Prusa MK3 to print just one. But please note that the time to print two similar parts on the Prusa MK3 is a bit more than 200% of the time of printing one (some extra time to be added as you need to setup up the printer twice). 


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