There are few filament vendors who sell by length. Perhaps this is because it’s difficult to mentally connect “length” with “will it be enough to make my object?” Weight seems to be a more friendly way to measure, as your slicer will usually tell you the predicted weight of the printed object. You can weigh the remaining filament on your spool and know the outcome of your print.
But that’s going to change. In fact, it already has. Some inventive filament manufacturers have developed composite filaments involving different materials. For example, wood filament is a mix of sawdust and a polymer. We’re seeing many similar experimental composite filaments emerge.
The problem arises when you use metal composite filaments.
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