Kuigi öeldakse, et sihimeetod tekitab sirgjoone rööpsena tugisihiga, omab tegelikult see meetod ka teadaolevat määramatust, mis on kuni 0,05 mm, seetõttu, et sirgjoone saamine ei ole alati 100 % võimalik.
Even though it is said to be parallel, in fact in this method there is also a known tolerance, which is up to 0,05 mm; this is because getting a straight line is not always 100 % possible.
