1. Cutting focus point on the workpiece<br> <br> It is also called negative focal length as the cutting point is not on the surface or inside the cutting materials, but on the above of the cutting material, which is mainly used for materials with high cutting thickness. It is located so mainly because the thick board needs large cutting range, otherwise the oxygen from the spray nozzle will easily cool down the cutting temperature as for the deficiency.The shortcoming is the cutting surface is rough, not so practical for cutting with higher precision.<br> <br> 2. Cutting focus inside the workpiece<br> <br> It is also called positive focal length, which is often used when the workpiece you cut is stainless steel or aluminum or steel board.One shortcoming is as for the focus point principle to the surface, the cutting range is larger than the cutting point , meanwhile under this mode, it needs larger cutting flow with enough temperature and longer cutting time.Therefore it mainly is used for stainless steel or materials with large hardness.<br> <br> 3. Cutting focus point on the workpiece surface<br> <br> It is also called 0 focal length, which is used to cut workpiece such as SPC, SPH and SS41 etc. When using, the focus of <a href="http://www.86factory.com/product/index/pid/14360">laser cutting machine</a> is near the workpiece surface, which ensures different smoothness. Generally the cutting surface that is near the focus is relatively smooth, while the lower surface that is away from the cutting focus is rough.This mode is used according to the different workpiece requirements of the upper and lower surfaces in actual applications.<br> <br> All in all, when we use the laser cutting machine to process different workpieces, we have to select the different focus mode to make full use of the performance and advantages of the machine.<br> <br>more in <a href="http://www.86factory.com/product/index/pid/14360">www.86factory.com</a>
