Where the thread first fails
Mark or film the handover point so the first poor engagement can be seen.
Cross-threading
What causes cross-threaded caps on an inline capper?
Cross-threading is usually created before final tightening is complete.
Direct answer
What causes cross-threaded caps on an inline capper?
Cross-threaded caps on an inline capper are commonly caused by a tilted cap start, variable bottle-neck finish, poor cap orientation, excessive bottle movement, poor pre-threading or spindle contact that begins before the closure is properly engaged. The correction starts with cap presentation and bottle control, not only torque reduction.
Evidence to collect before changing settings
Which samples fail
Separate one cap batch, one bottle batch or one format from a general setup issue.
Whether faults repeat after restart
Cross-threading after stop/start often points to feed handover, bottle pitch or accumulation.
Related guidance
Continue the specification
Spindle capping machines
Compare the main automatic, compact and semi-automatic capping routes.
FAT checklist
Plan evidence for sample testing, acceptance and handover.
Ask Lancing to review the pack
Send bottle, cap, samples, target output and any known fault evidence.