Cad a chiallaíonn geansaí seamna dall?

Ceann léim seamna dall: toisc nach gclúdaíonn an seam an ceann ingne, cuirfidh sé faoi deara an ceann léim seamair.

https://www.yukerivet.com/news/the-core-of-the-blind-rivet-is-not-completely-pulled-out-what-is-the-reason-for-the-fracture/