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    7 Reasons Why My Diamond Wheel is Chipping My Glass

    Updated: February 21, 2024 Published: March 3, 2023

    If you work in the glass cutting and grinding industry, you know the importance of having a precision diamond grinding wheel for glass specifically. It’s an essential tool that makes your job much easier. But, have you ever experienced the frustration of chipping? You know, when small pieces of the glass break off during the grinding process and leave you with an uneven surface, not to mention the loss of material. It’s a common problem, but the issue typically stems from 7 main causes. These causes include:

    glass pencil wheel

    1. Too Coarse of Grit

    diamond wheel with too coarse of grit can cause chips in your glass. With too coarse of grit, the individual diamond particles are too large and therefore unable to effectively grind the surface of the glass. The large particles cause excessive pressure and impact on the glass, leading to the breakage of small pieces and chipping.

    To fix this issue, the operator can choose a finer grit diamond. Finer grit diamonds have smaller diamond particles that can more effectively grind the surface of glass without causing excessive pressure or impact. You can also consider reducing the rim speed of the wheel or adjusting the feed rate to reduce the pressure and impact on the glass.

    2. Not Enough Coolant

    Without enough coolant, overheating can cause stress and weaken the structure of the glass, making it more prone to breakage and chipping. Coolant also helps to flush away debris and contaminants generated during the grinding process, which can build up and cause additional stress on the glass.

    Fixing this simply comes down to making sure you always use enough coolant when grinding glass. But, before simply adding more coolant, ensure your coolant is always properly mixed and regularly changed.

    3. Bad Spindle Bearings

    Worn-out or bad spindle bearings can lead to an uneven rotation of the wheel. This uneven rotation causes excessive vibration and instability during the grinding process which can lead to increased pressure and impact on the glass. Bad spindle bearings can also cause excessive wear and tear on the wheel. This wear and tear impacts its performance and contributes to chipping.

    You can avoid bad spindle bearings from causing glass chipping by regularly inspecting the spindle bearings and replacing them if worn or damaged.

    glass in process

    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.

    6. Poor Wheel Balance

    A poorly balanced wheel leads to excessive vibration and instability during the grinding process. This causes harsher impacts on the glass and a less even finished surface of the glass.

    Balancing a diamond wheel involves adjusting the weight distribution of the wheel to ensure it spins evenly. To balance a diamond wheel, you can follow these steps:

    1. Mount the wheel on a balancing machine
    2. Check the unbalance
    3. Remove weight from the heavy side by drilling or milling the steel body of the wheel
    4. Recheck the balance after removing the weight
    5. Repeat as necessary

    By regularly balancing your diamond wheel, you can reduce wear and tear as well as improve its immediate performance.

    7. Contaminants on the Surface of the Glass

    Any contamination on the surface of the glass you’re grinding can act as an obstacle during the grinding process. Your diamond wheel can catch on to these obstacles causing the glass to chip. Keeping contaminants off the surface of the glass you grind with your diamond wheel can also help maintain the condition of your wheel and reduce wear and tear.

    Thoroughly cleaning the surface of the glass immediately before grinding the glass reduces the risk of recontamination after a cleaning. You can clean glass before grinding using a solvent or abrasive cleaner and a soft cloth. To further reduce the risk of contaminants on the surface of the glass, consider regularly inspecting the glass and the wheel during the grinding process.


    It’s important to understand that regardless of the reason your diamond wheel chips your glass, you can come up with a solution. Whether it be the grit of the diamond or maintenance issues with the wheel, with a little bit of extra care and attention you can avoid chipping glass. You also might be chipping glass due to maintenance issues you’ll want to resolve so you can maximize the lifespan of your diamond wheel.


    diamond grey min


    Whether you are looking for general guidance or are ready to get a quote, we are dedicated to helping you find the right solution – and if we can’t provide the exact wheel you need, we will let you know. We hope you’ll explore the ways our team can help your business stay ahead of the competition.