Thread: How is grit determined?

Here is an interesting article on Grit Size of Silicone Carbide. Grit size and consistency would depend on it use and the quality of the product produces. For example, better quality stones would be more consistent, “graded grit” (at or near stated size), than cheaper stones that may use “ungraded grit”, or random size up to the stated grit.

“Silicon carbide occurs naturally as the mineral moissanite; however, it is extremely rare, only found in tiny quantities in a limited number of locations. All of the silicon carbide sold as an abrasive is manufactured. It is produced by placing a mixture of coke (a fuel and carbon source), sand (a silicon source) and sawdust (another fuel and carbon source) in an electric resistance furnace and heating to a very high temperature. The silicon carbide is then crushed and screened into specific sizes. These "grits" and "powders" are used as cutting, grinding and polishing media.”

“Some silicon carbide is sold as a "graded grit." That means all of the particles are very close to the same size. For example, an abrasive sold as "80 grit" would have almost all of the particles about 177 microns in size. Graded grit must be carefully crushed and screened to be sure that all of the particles are approximately the same size. “


“In contrast, "ungraded grit" has a wide range of particle sizes. For example, an abrasive sold as "60/90 grit" would have a range of particle sizes smaller than 60 grit (250 microns) but larger than 90 grit (166 microns). Ungraded grits do not require the same level of processing needed for graded grits. That allows ungraded grits it to be sold for a lower price than graded grits.”

High quality sand paper and Wet and Dry would do much the same, which is probably why you can easily see the difference in performance in quality, of Wet & Dry and sanding belts.

As with most things, everybody has their own “system/rating” and screed screens.

Originally Posted by Euclid440

Here is an interesting article on Grit Size of Silicone Carbide. Grit size and consistency would depend on it use and the quality of the product produces. For example, better quality stones would be more consistent, “graded grit” (at or near stated size), than cheaper stones that may use “ungraded grit”, or random size up to the stated grit.

“Silicon carbide occurs naturally as the mineral moissanite; however, it is extremely rare, only found in tiny quantities in a limited number of locations. All of the silicon carbide sold as an abrasive is manufactured. It is produced by placing a mixture of coke (a fuel and carbon source), sand (a silicon source) and sawdust (another fuel and carbon source) in an electric resistance furnace and heating to a very high temperature. The silicon carbide is then crushed and screened into specific sizes. These "grits" and "powders" are used as cutting, grinding and polishing media.”

“Some silicon carbide is sold as a "graded grit." That means all of the particles are very close to the same size. For example, an abrasive sold as "80 grit" would have almost all of the particles about 177 microns in size. Graded grit must be carefully crushed and screened to be sure that all of the particles are approximately the same size. “


“In contrast, "ungraded grit" has a wide range of particle sizes. For example, an abrasive sold as "60/90 grit" would have a range of particle sizes smaller than 60 grit (250 microns) but larger than 90 grit (166 microns). Ungraded grits do not require the same level of processing needed for graded grits. That allows ungraded grits it to be sold for a lower price than graded grits.”

High quality sand paper and Wet and Dry would do much the same, which is probably why you can easily see the difference in performance in quality, of Wet & Dry and sanding belts.

As with most things, everybody has their own “system/rating” and screed screens.

Great info, thanks. Where did you find this? Anyone know of any companies that produce abrasive particles that might have more in depth steps regarding this process?

OK, OP:
http://www.engis.com/pdf/Particle-Si...s-summer07.pdf

~Richard

Just had to one-up us all, didn't ya?