beat, pound, strike, tap out message
搥 centers on striking or hitting with force: beating, pounding, or striking something. The sense of tapping out a message is a specific application of rhythmic striking.
搥 combines 扌 (hand) with 追, which likely contributes the sound and may suggest a following or repeated action, fitting the idea of striking repeatedly.
The hand radical 扌 beside 追 suggests a hand chasing or following something with repeated blows: beating, pounding, or tapping out a rhythm.
For タイ, imagine a hand beating a tie-dye shirt against a rock: tie -> タイ, and the pounding action sets the dye.