Finally the promised thrum technique that I use! Here is a finished mitten I did a few years ago showing both the right and wrong sides of the mitten.
In my current project, I have finished the wrist of the first mitten and have started the body of the mitten. You should be able to use any basic mitten pattern. Start the first thrum after the increase row and then knit in a thrum every 3rd or 4th stitch and then knit three or four rows before you knit the thrum row again. Repeat to end of pattern. Use the same interval each time, i.e. thrums every 3rd stitch, every 4th row.
Here is the template I am using for sizing purposes. As you can see compared to my hand, the hand belonging to the potential owner of these mittens is rather large.
I used some alpaca roving that I have and pulled 3 inch lengths off of (approximately) and then I further divided those 3 inch pieces lengthwise. If you have very thin roving you don't need to do this. Any fiber will do for thrums but alpaca is very warm and I had some in stock. It's also what I used in my mittens and I was very pleased with the results.
Insert needle for a knit stitch. Take a piece of roving, twist it in the middle to make it easier to work with, make a loop by folding it in half and then wrap the loop around the needle (below), making sure that the ends of the roving on either side of the needle are equal in length.
This shows one thrum after it has been knit into the stitch. As you can see it is a little loose. Give both ends of each thrum a tug to tighten up the stitch after you complete the row. (As usual my flash is overpowering the photo and I don't know how to stop that other than not use it)
After the row of thrums is complete push down all the tails into the mitten so that they are out of the way for the next rows of knitting.
This is how it looks on the right side. You can see the brown thrums knit into the mitten.
Stay tuned for part two when you get to see the finished mitten. That probably won't be for several days to a few weeks!