4. Removing Too Much Stock
Removing too much stock in a single pass increases the risk of overheating. As mentioned earlier, this overheating can cause your glass to chip as it causes stress and weakens the structure of the glass.
Instead of trying to remove a large amount of stock in a single pass, use multiple lighter passes to achieve the desired shape. Although this can take a bit more time, it minimizes the risk of overheating and ensures a smoother end result. To reduce the stock you remove in a single pass, adjust the feed rate.
5. Grit is Too Blocky
With grit that’s too blocky, you end up with the same issues as too coarse of grit. Except, instead of the size causing the issue, the shape of the grit causes the issue. Grit that is too blocky does not micro-fracture and is too dull to cut glass cleanly. The lack of micro-fracturing results in the grit becoming rounded over and dull and dull grit can not cut cleanly resulting in chipping of your glass. On top of chipping, blocky grit can also cause an uneven grinding surface, leading to an inconsistent finish and an increased risk of chipping.
To avoid the blockiness of your grit causing issues when grinding glass, use a diamond type with an angular grit. This angular grit retains a sharper edge reducing the risk of fracturing. You can also reduce these issues by reducing the speed of the wheel.