The guide for new buyers when buying concrete grinding discs The concrete grinding disc is also called as diamond grinding disc, concrete grinding shoes, diamond grinding shoes, diamond grinding segment, concrete grinding segment, diamond grinding wheel, concrete grinding wheel, etc. As the increasing new buyers of Sunny concrete grinding disc, here we made this guide for them and hope it is helpful.     Concrete floor grinding disc is an efficient diamond tool for grinding concrete and terrazzo floor. It is also great for coating removals when welded with PCDs or low grit arrow type diamond segments. There are lots of different types concrete grinding discs to suit different floor grinders like HTC, Lavina, Klindex, Edco, ASL, Blastrac, angle grinder, etc.. (Sunny developed various excellent concrete grinding discs for these grinding machines, you can download our latest concrete grinding disc catalog here) Before buying concrete grinding discs, there are 2 points we should notice: First - Knowing the concrete grinding disc type you needed Different floor grinders use different shapes of the concrete grinding disc. Except for some trapezoid shape, most concrete grinding discs are not compatible. For examples, concrete grinding disc for these following floor grinder brands is unique and not compatible. Please check the different floor grinder brands as follows, including HTC, Lavina, Klindex, Husqvarna, Scanmaskin, Werkmaster, Edco, Blastrac, and etc.. That’s why we classify our concrete grinding disc by floor grinder brands or connections, to guide to find the right type concrete grinding disc quickly. There is a simple way to find the right type concrete grinding disc – to send us the picture of the disc you used and we will recommend the right disc to you. Second - Knowing the details of material to be ground or the coating to be removed The concrete grinding discs have 2 functions, one is to grind concrete or terrazzo floors, and the other is to remove coatings. When grinding concrete or terrazzo floor, there are 2 things you should know: 1. The hardness of concrete floor or terrazzo floor This information is essential, because different hardness concrete/terrazzo floor needs a different metal bond to fit them. The hardness of concrete and bond are opposite. For example, if the concrete to be ground is VERY HARD, then the bond should be VERY SOFT. The following is our hardness standard, and we use different colors to distinguish different hardness of concrete. Hardness of Concrete/Terrazzo Floor PSI MPA Bond Type Code Color Extremely Hard 6500-9000 C50-C65 Extremely Soft XHF 　Blue Very Hard 5000-7000 C40-C55 Very Soft VHF 　Purple Hard 4000-5000 C30-C50 Soft HF 　Black Medium Hard 3000-4000 C20-C40 Medium Soft MHF 　Red Soft 1500-3500 C15-C25 Hard SF 　Yellow Very Soft 1000-2000 C10-C20 Very Hard VSF   Orange 2. The grinding result you wanted  When grinding, we can classify it to 3 types: coarse grinding, medium grinding, and fine grinding. However, how to make it? The answer is to use different diamond grits. The following table can help you to find the right diamond grit to fit your grinding works. Application Diamond Grit Range Segment Shape Recommended Coarse Grinding 6#, 16# Arrow, Stair, Segment Bar Medium Grinding 36#, 60#, 80# Segment Bar Fine Grinding 120#, 180#, 220# Round   When removing floor coatings, there are one things you should know: The direction of PCD of PCD grinding discs - clockwise or anticlockwise? For PCD grinding discs, the direction of PCD you should notice. There is only one rotation direction which the PCD grinding tools can work properly. The direction of PCD depends on the rotation direction of your floor grinders. Some of our customers will place an order of PCD grinding discs with both directions (clockwise and anticlockwise). If you are using the arrow-type concrete grinding disc to do the coating removal work, the direction of the arrow segment should also be noticed. The direction rotation direction should along the tip of the arrow. Now, do you have a rough idea of the concrete grinding disc? If you have other questions, we welcome you to send your questions to our email: info@sunnydiamondtools.com and we will reply to you as soon as possible.