Method of separating a floorboard material

A set of floor panels comprising a joint system for mechanically joining floor panels including a first floor panel and a second floor panel, the joint system comprising:

• a flexible tongue;
• and
• a tongue groove of the first panel, wherein
• the flexible tongue is adapted to interact with the tongue groove for mechanically joining the first and second floor panels,
• the flexible tongue is in a holding groove of the second panel, the holding groove having an opening, a base, and a width direction extending from the opening to the base, the flexible tongue being displaceable in the holding groove and displaceable in the width direction of the holding groove,
• the flexible tongue comprising a protruding part which protrudes from the opening of the holding groove of the second panel and beyond an outermost portion of the second panel in the width direction, and the flexible tongue further comprising an inner flexible part within the holding groove of the second panel, and
• the flexible tongue comprises a plastic material,
• wherein the first and second floor panels are configured to be mechanically joined together by displacement of said first and second floor panels substantially vertically towards each other, while at least a part of the flexible tongue is resiliently displaced in the width direction of the holding groove until adjacent edges of the first and second floor panels are brought into engagement with each other substantially vertically and the flexible tongue is then displaced towards its initial position during relative vertical movement of the first and second floor panels, and is in the tongue groove.