The most common issue with V-grooving over the ST250 length is actually down to user technique and is easily solved. We have a short video explaining this in more detail which can be found in our Steeltrak support page in the tips and tricks section – https://www.keencut.com/support-category/steeltrak/
Have a look at this video and see if this sorts the issue out for you. If not please get in touch again on [email protected] and I will be abel to offer further assistance