Tips for cutting vitrified paving on a table saw
Tips for Cutting Vitrified Paving on a Table Saw
Many people are experiencing problems when cutting vitrified paving on a table saw as the diamond blade becomes polished & stops cutting. This is due to a combination of factors such as the power of the machine, the hardness of the material & the amount of water being used. We are in the process of developing a blade purely for these machines but in the meantime here is an explanation of what is happening to the blade, how to try to avoid it & thus get the best performance out of the blade.
Glazing or polishing
- As a diamond blade cuts the exposed diamond grit begins to break up or is torn out of the segment
- The metal bond of the segment should also begin to wear in order to expose the subsequent layers of diamonds so that it can continue cutting
- If the metal bond does not wear back then there will reach a point where no diamond is exposed and the blade will slow down and eventually stop cutting
- The tip of the blade will now feel smooth and this is known as glazing or polishing
- Continued use in this state will cause the blade to overheat and the segment may “mushroom” over
Typical causes of glazing
- The material being cut is very hard & not abrasive enough to wear back the metal bond
- Higher power machines & machines that rotate faster will wear a blade more, lower power machines will wear a blade less or not at all
- Using a lot of water can wash away any abrasive slurry which stops the blade wearing
All three of the above factors apply when cutting vitrified paving on a table saw, as previously mentioned we are trying to develop a blade that will alleviate this problem but in the meantime the following tips may keep you cutting.
- Because the blade is not wearing whilst cutting you need to artificially reproduce this action by dressing (wear it back to reveal the diamond) the blade periodically. This can be done by cutting something abrasive such as low strength concrete block, grinding it with an abrasive disc on a grinder or using a sharpening stone.
- Please bear in mind, the more polished the blade is the more effort will be required to reveal the diamond. This will not be just one run through a concrete block! You need to dress it until you can feel & see the diamond grit on the tip of the segment.
- If you don’t wear it back sufficiently there will not be enough diamond exposed to allow the blade to continue cutting.
- You should dress the blade as soon as you feel it slowing in the cut, don’t wait until cutting is impossible. A little & often is the best way.
- We have also had some success by using 2 x 10mm sweeps to cut the flag rather than 1 cut at full depth. This will allow the blade to rotate more freely & maintain a higher rpm.
Hopefully if you follow the above guidelines you will be able to keep cutting.