When every you use someone who you don't know or who doesn't truly know your machine, then YES, YES, YES take something to try sewing on. We become one with our machines, so we do know how it should feel and sound as well as what our stitches should look like. I used a different repair man that came highly recommended to me. For the next 3 months I had to take the drive to this man to have him fix it. It never sounded the same, when I had to take it in for the 3 time in a week. I was hot, so I took it in with the mess it had made. So he started to fix it with me standing in front of him, this time as he was adjusting it I kept telling him it was making too much noise. This time he did get it adjusted correctly. My machine started sewing and sounding like a new machine again, even my repair man was awestruck at the difference a screw turn made. Now that I have him broken in, I have two machine repairmen for my machines. So yes sew something it will make you feel better before you leave, he will understand.