DIYbanter - View Single Post - Mixing small amounts of 2-cycle fuel

Bill[_47_]

wrote:
I only want to mix a cup of gas at 40:1 how much oil will it take

To answer your question expressly, it will probably take less oil than
you have, unless you are out of oil. If you start with a cup of gas,
you'll need to add a tenth of a quarter cup of oil to it (alternatively,
you could instead add a quarter of a tenth of a cup of oil--which
depending upon how you go about it, may yield greater accuracy). This
will be facilitated by the use of a cup with metric graduations. Making
your own graduated measuring cup from a narrow cylindrical container
(think of a test tube), should give you results that are as accurate as
you please. If you would like to end up with exactly a cup of gas and
oil, the calculations get messier. It may be easiest to begin with a
cup of gas, proceed as in the first case, and then discard all but a cup
of that solution (well-mixed). Alternately, you could look up how many
teaspoons or tablespoons are in a cup (8 fluid oz.) and divide that
number by 40 to determine the amount of oil that you would need in terms
of those units (2 decimal digits will probably suffice, depending on
your purposes, if you are using a calculator). Don't smoke while you
are performing this work. Hope this helps! Good luck!