Where does “törkkääminen” come from?

törkkääminen (Finnish) comes from Finnish törkätä, from Ingrian törkkä, from Russian тёрка, from Russian -ка, from Proto-Slavic -ьka, from Proto-Balto-Slavic -ikaʔ, from Proto-Indo-European -ikeh₂.

Ancestry of “törkkääminen”, step by step

Step	Language	Word	Meaning
1	Finnish	törkätä	to jab or poke once
2	Ingrian	törkkä	grater
3	Russian	тёрка	grater; float; huller
4	Russian	-ка	now, just
5	Proto-Slavic	-ьka	—
6	Proto-Balto-Slavic	-ikaʔ	—
7	Proto-Indo-European	-ikeh₂	—

Every word from Proto-Indo-European -ikeh₂ →Every word from Russian -ка →Every word from Proto-Slavic -ьka →