Helpful Hints Corner
Do you have any helpful hints for our visitors? Send us your techniques and they will be posted on our site!
When core drilling in an area where a mess is a problem. Take a 5 gal. plastic bucket, cut 2 to 3 in. ring off the top and set around the area to be drilled then seal with caulk. This will contain the water and mess for easy cleanup.
Jerry Pursell
One of our customers said when he has to cut with a core bit and there is no water available to cool it down, they pack the barrel with ice. As the bit heats up the ice melts and cools downs the bit.
Diamond Blade Description
A diamond blade is a circular steel disc with a diamond bearing edge. The diamond edge comes in 3 main styles:
Segmented, Continuous Rim, or Turbo.
The blade core or blank is a precision made steel disc, which sometimes has slots. These slots (also called gullets) provide cooling by allowing water and or air to flow between the segments. The gullets or slots also relieve stress and help prevent cracking of the core. They allow the core flexibility while under cutting pressure.
Blade cores are pre-tensioned at the factory so the blade will run true and straight at pre-determined cutting speeds. This tensioning allows the blade to remain flexible enabling it to bend slightly under cutting pressure then return back to its original position. All blades are designed to run at certain rpm's. While the tool or blade shaft is working it is essential for safety and optimum performance that they be run at the correct rpm.
Diamond segments or rims are made up of a metallurgical formula of diamonds and metal powders. Manufactured diamonds are primarily used in various grits, sizes, and qualities or grades. During the manufacturing process, the metal powder and diamond grit mixture is hot pressed at high temperatures to form a solid metal alloy. This is generally referred to as a bond or matrix. The diamonds are held within this bond. The segment is slightly wider than the core, allowing side clearance. This prevents the steel core from dragging or binding in the cut while still allowing the cutting edge to penetrate through the material. Depending on the aggregate being cut, different mixtures of diamonds and metal powders are used for various applications.
As the blade spins through the cut, it begins to cut or grind through the material. The material being cut also wears away the blade fracturing the diamonds inside the bond. As the bond wears, it discards the fractured diamonds and exposes newer sharper diamonds. Highly abrasive material will cause the matrix to wear even faster, allowing newly exposed layers of diamonds to cut.
Cutting with a Diamond Blade
(how a diamond blade works)
Diamond blades don't actually cut into a surface like a knife. They grind the surface. During the manufacturing break in process individual diamond crystals are exposed on the outside edge and sides of the diamond segments or rim. These diamonds do the grinding. The diamonds are locked into place by the metal matrix or bond. Behind each diamond is a bond tail which helps to support the diamond.
Choosing the Right Blade
(Factors in choosing a diamond blade)
Initial price of blade or cost effectiveness of blade?
Matching saw and horsepower to blade being used.
Type of material being cut.
Do you want a segmented, serrated or continuous rim blade?
Wet cutting or dry cutting application?
Dry Blades vs. Wet Blades
Wet Blades
Wet diamond blades must be used with water to prevent excessive heat buildup during operations. Water also helps to clear away dust and cuttings from cutting area and blade.
Wet Blade Applications
A continuous flow of water is needed to prevent excessive damage. Using a wet blade without adequate water, even for only a few seconds can cause excessive heat and blade damage, it can also pose a safety hazard.
Dry Blades
Dry diamond blades can be used either wet or dry. These blades are cooled by the airflow around the blade preventing excessive heat from doing damage the blade.
Dry Blade Applications
Every 10 to 15 seconds, take pressure off the blade, back it out of the cut, and allow it to run back up to full speed for several seconds. This allows the air to flow around the blade cooling it!
Questions to Ask When Using a Walk-behind Saw
What type of aggregate are you cutting?
Are you cutting green or cured concrete?
What is the psi of concrete being cut?
What is the size of aggregate being cut?
What is the hardness of aggregate?
What type of sand within aggregate mix being cut?
What type of steel rebar reinforcing is in the material being cut?
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