Properly sizing your bead to your hook can play a huge role in the overall performance of your fly. While there are a number of factors to consider - including the type of bead you use, which I will cover in another post - here's a basic guide I've always used to get my flies put together for success:
This sizing chart is a great rule of thumb - but certain patterns require you to stray away from these rules.
For Example - some Midge patterns are designed to be very "top heavy" to better replicate the early stage of a hatch. I typically tend to size up the bead to achieve this - a size 18 Midge would get a 2.4mm bead, a size 16 Midge might even get a 2.8mm bead if I wasn't jeopardizing the proportions of the tie or using a bead that slides over the eye of the hook, because, what good would that do? Always use your best judgement and the good news is that if you properly sampled the waters and matched up your coloring...a bead that's too small or too big usually won't matter as much, a hungry fish will take a shot at your presented fly either way!
Happy tying and always feel free to drop me a line via Facebook, Instagram or the contact link on this site. I'd love to hear from you!