Three yarn samples of a certain weight (≈2 g) are weighed on a digital scale with a precision of 0.001 g before they are placed in the test machine. Then, 10 cc of ethanol is added to each sample using a gauged pit, letting the oil on the yarn be dissolved in the ethanol. The oil-containing solvent is then drained using a pushing rod and poured onto a weighed small aluminum container that is being heated. This heat is adjustable and causes the solvent to evaporate with only the oil remaining in the container ultimately. This process is re-performed using two more rounds of ethanol, and the oil-containing container is weighed after it has cooled down. The yarn sample is dried in an oven. The spin finish oil content can be determined using the oil weight and dry yarn weight.