I ordered a 0.5 KG spool of Makerflex Glow in the Dark filament from Makergeeks. I ordered Clear and Opaque PLA with it. The Makerflex plastic is called TPEE. The entire spool of it seems to have small bubbles in it. I even confirmed this by cutting one of the bubbles, and I could fit a small piece of metal inside, so it is not just a funky coloring. Does anyone know if this is normal? I can't get in touch with Makergeeks themselves. Will it damage my printer? I have a stock Tevo Tarantula.
Bubbles are a defect. Two problems can occur:
- The air in the bubble will be under pressure when heated and can cause a little blow-out when the plastic sides of the bubble are soft enough that they can no longer contain the pressure. Depending on where this happens, it can either result in little spatters of filament being spit through the nozzle at the printed object, expanded craters which could increase the diameter of the filament and make extrusion more difficult, or, if at the end of a print job, the expanded filament may cool and be too large diameter to feed for the next print job.
- If the air escapes without causing any other problem or it was created by cavitation, the volume of the bubble causes under extrusion, since it represents missing plastic. The extrusion volume is controlled by driving a specific linear distance of filament and assuming a specific filament diameter and 100% plastic. Underextrusion hurts print quality, print strength, and surface finish.
Bubbles in the filament indicate a failure in the filament manufactury. As @Granny said in the comment, this is defective filament which should be returned for a refund. If you use it, understand that it will not give results that are the best your printer can deliver.