The Thing about Thumbs

The thing about thumbs is that they stick out.

What this means for mitten construction is that you need to allow some extra room for the thumb and plan ahead for a thumb socket. Since your thumb is so much lower on your hand than the rest of your fingers, the hole for your thumb has to be correspondingly earlier in the mitten.

A thumb and its gusset

To make sure my thumbs are happy in these mittens, I made a gusset -- essentially a planned, triangular addition to a sewn or knitted garment. Every other row starting at the base of my thumb, I increased two stitches until I had increased 16 stitches. The row after this increase, I removed those stitches and placed them on extra yarn to just hold them until I was ready to attach the thumb tube.

Thumb gusset stitches on waste yarn

When I've finished both mittens, I'll come back with the midnight yarn and put those stitches back on the needle and knit those. I'll also pick up some additional stitches along the inside of the thumb hole to make sure that there isn't a gap in my mitten.

Without a gusset, the thumb won't be able to move as freely, though it does require some additional planning to successfully incorporate it into the mitten. A mitten without a gusset is basically a tube with a small hole in the side for the thumb to stick out.