Theodore Roethke was a German immigrant who was an American poet which characterized its imagination. Most of his poems were inspired by the image of his childhood like "My Papa's Waltz".
This poem at first reading creates an image of an abusive father who comes home and beats his son. But it is a complete opposite expression. The poem "My Papa's Waltz" is positively and related to the son's memories which are still fresh with all the details after he is grown. It is about the relationship between a father and son who spend his time at the end of the hard working day in an awkwardly manner.
Father who comes home and dances in an awkwardly manner to spent some time with his son before he goes to bed. The boy's father works all day and comes home at time of his son's bed. He wants to spend some time with his son and so the author describes the waltzing memories of a boy with his father dancing on his feet. In the second stanza it shows that the mother is not doing anything to stop her husband from playing with his son even though the dancing is ruining her kitchen table, because she understands the feeling of a father and a son relationship and she don't want to ruin the time a father is trying to spend with a son riled up rather than trying to calm him down for sleep.
In the third stanza it seems that he describes the wrist of a hard labor working father who makes his son dance by stepping on his foot and holding his hand with his rough wrist. The father's knuckles were battered by working as a laborer and so it feels him very hard and rough. The line My right ear scraped a buckle' meant that whenever while dancing he would miss the step his head would hurt him with his father's belt buckle.
In the last stanza he mentions about beating time on his son's head which simply mean that the father is trying to keep the rhythm of the dance it does not mean anything violent.
In short a father coming home from work at time of his son's bed...