TgO Ex26:24 :וִיהוֹן מְכִונִין"מַכוְנִין" מִלְרַע וְכַחדָא יְהוֹן מְכִונִין"מַכוְנִין" עַל רֵישֵיהוֹן‏ : they should be turned downward and be turned together on their tops
See the entire entry for kwn vb. to be firm