Straight edge hat

I’ve done a couple of beanie hats where I wanted a nice straight edge (no ribbing). So I knit it bottom up, then crochet a row of SC around the cast on edge. Worked a treat.

But now I have one where I had to frog up from the bottom to lose a couple of rows, then cast off. I did the row of SC, but it just keeps rolling up all the time.

Any suggestions?

I’m not sure…maybe do the single crochet from the inside instead of the outside? I’ve never done a hat that way. :think: