You will produce small quantities of methanol when distilling using commercial ‘spirit yeasts’ and sugar/dextrose. The temperature ethanol (drinking alcohol) boils off at is 78C-82C, which is why we are always told to keep our still between these temperatures. The acetone and methanol boiling temperatures are a lot lower, and this is why they are the first impurities to come out of your still, hence why you should always throw the first 150ml of alcohol (impure alcohols/methanol) that comes out of your still. As we are only fermenting sugar with a known yeast and nutrient mix (often refered to as ‘Turbo Yeasts’), we know how much by products such as methanol are to be discarded at the beginning, making the process of distillation safe.
If you wish to distill other mixtures (other than brew shop yeast and sugar/dextrose) then the methanol quantity produced is unknown and could prove disastrous!