I used 1/4" copper tubing to make a straw for my coffee. The comfortable length seems to be from 17 to 19 cm. I've settle on 18 cm as perfect. Extreme people will want either 15 cm or 20 cm. So start with 20 cm and keep cutting until you're happy. It functions great as a stirrer, and how hot it is when you touch it lets you know how hot the liquid is. 1/4" seems to be on the thick side, so many people will prefer 1/8" tubing. With 1/8" tubing, you could make it into a spiral at the top end and maybe you could sip slow enough for the liquid to cool as it comes it. I am very particular about my spoon and coffee cup quality and SIZE since I use them everyday, and I use a straw to keep my front teeth from getting yellow from the coffee. So I am very happy to be married to a quality straw as well.