Replace the reciprocator on the Butterfly Embroidery machine
How to replace the reciprocator on your Butterfly Embroidery machine (2013-2014). This video will show taking the head off, swapping out the part, and putting the head back on the machine; this video is adequate to use as a general video on removing and replacing the head.
The reciprocator can be damaged by hitting a hoop with the needle, for instance. In most cases however, the strength is such that it will force the needle to penetrate right through the hoop and then do it some more; do trace your designs and be extra careful with any new design or tight hoop size.
Older Butterfly models (2012-earlier) have small differences, particularly in the wiring and the horizontal linear bearing; but is very similar overall. Take pictures of the disassembly process if your machine is different.
It is recommended to change out the entire reciprocator (plastic plus encasing metal brackets, the entire module as shown in video), as there may be small height or shape differences if trying to disassemble it and trying to move the plastic part alone to the old bracket.