This article on restoring worn out and glazed over diamond blades is from our archives. What do you think? Let us know in the comments section!
There are two main reasons why your diamond blade is cutting slower or has stopped cutting: it’s either worn out or glazed over.
A worn out diamond blade should be replaced, period, end of story. You shouldn’t try to squeeze a few more feet out of a worn out blade, because a worn diamond blade is more likely to break or cause life-threatening accidents. If you’re using a Ductile Iron Safety Blade, Fire Rescue Safety Blade or Ductile Iron Ring Saw Safety Blade, see this article on Safety Blade wear patterns to see if your diamond blade is worn out.
A glazed over diamond blade, on the other hand, still has life in it and doesn’t need to be replaced. All you need to do is “dress” it by running it through an abrasive material – like asphalt, sandstone, masonry block, or a dressing stick – to restore its cutting speed.
Keep an eye on your diamond blade if it gets glazed over, though. If it glazes over again after you dress it, then your diamond blade may be too hard for the material that you’re cutting. You can dress it again if it becomes glazed over again, but repeated dressings can slow down your cutting, not to mention make your diamond blade become worn out faster. If you find yourself repeatedly dressing your diamond blade, consider getting a softer one.
So why is your diamond blade becoming glazed over? To answer that question, we first have to explain how your blade is supposed to cut.
Your diamond blade has cutting segments comprised of diamond grit mixed within a metal matrix or “bond”. When we talk about hard and soft blades, we mean the hardness or softness of this bond.
The diamond grit on the surface of the cutting segment’s bond does the cutting. All the bond does is hold the grit on the blade. Ideally, as the grit on the segment’s surface wears down during cutting, the bond wears down, too. This sheds worn surface grit and exposes fresh, sharp diamonds deeper within the cutting segment. When this process works, your diamond blade cuts at more or less the same rate throughout its life.
You run into problems, however, when the bond of your diamond blade is too hard for the material that you’re cutting. When this happens, the surface grit wears down faster than the bond. If this surface grit wears down too much, then your diamond blade becomes glazed over and stops cutting. Dressing restores the performance of your diamond blade by wearing down the bond until it sheds worn surface grit and exposes fresh diamonds.
To avoid having your diamond blade become glazed over, you should, as a rule of thumb, cut hard materials with a soft blade. That’s because soft bonds wear down faster in hard materials, allowing your blade to shed worn diamonds faster, expose fresh grit faster, and avoid becoming glazed over.
For more information, visit Desert Diamond Industries’ frequently asked questions page.
“Frequently Asked Questions.” Desert Diamond Industries. Desert Diamond Industries, n.d. Web. 29 Nov. 2012. <http://www.desertdiamondindustries.com/faq.php>.