Learn Turkish: Tahtayı mengeneye böyle sıkıca bağla. - Clamp the board tightly to the vise like this.

Böyle is a demonstrative adverb of manner that describes how an action is performed. While bunun gibi compares nouns (meaning "like this thing"), böyle modifies the verb to mean "in this way" or "like this." In this sentence, the speaker is likely demonstrating the physical action of clamping the board while speaking.

What does the suffix "-ca" do in the word "sıkıca"?

It turns the adjective sıkı (tight) into the adverb sıkıca (tightly). Adding the -ca or -ce suffix to an adjective is a very common way to create adverbs of manner in Turkish so they can describe how an action is done.

Why does "mengene" (vise) take the dative suffix "-ye"?

The verb bağlamak (to tie, fasten, or clamp) requires the dative case for the object you are attaching something to. Since you are fastening the board to the vise, mengene takes the dative suffix -ye to become mengeneye.

Doesn't "bağlamak" usually mean "to tie"? Why is it translated as "clamp" here?

Yes, bağlamak literally means to tie or bind. However, Turkish uses it broadly for any action of securing or fastening one object to another. In a workshop context using a vise (mengene), securing the board is naturally expressed with the command bağla.