When it comes to making the cut, flexibility is also important. Consequently, some manufacturers, such as Stone Construction Equipment, have designed their saws to allow cutting on either side of the machine. "We have a shaft that enables you to cut on either the right side or the left side," notes Varel. "That's great for making your cut, then you can do a flush cut on the left side."
To facilitate switching the blade, the company includes a wrench mounted on the saw. "You can swap off the blade, hook it up to the other side, then move your blade guard over," Varel points out. "It's a little added convenience."
Other features available on mid-size and larger saws include built-in water tanks, as well as electric water pumps to deliver continuous flow and pressure throughout the cutting process. "Keeping the blade cool is a big contributor to productivity," says Varel. "The hotter a saw blade gets, the more warpage it will get and the worse the cut will be."
Husqvarna has also introduced an electronic tracking device on its larger models. According to Tremain, operators were previously required to manually adjust the rear axle. "It was so involved to change the tracking, a lot of guys would just lean real hard on the handle bars," he says. "That's real fatiguing, back breaking stuff. It's also really hard to cut straight when it's not set properly."
The electronic tracking system enables tracking to be adjusted left or right with the flip of a switch.
Make an effective match
Although the length and depth of cuts is important, the material your customers will be cutting can have just as much influence on the type and size of saw required for a particular application.
"Aggregate, slab size, required depth of cut, curing time and sometimes sand can be important aspects of the project to consider when assessing saw/blade needs," says Nabarrete. "For example, if the weather is hot, the concrete may cure faster, thus requiring the joints to be cut sooner. In that case, a larger saw or additional saws on the job will help speed up the process."
Green concrete actually requires a saw specifically designed for such conditions. Most green cutting saws are lighter weight and more compact than traditional models, enabling them to get onto concrete sooner without disturbing the finished surface. For example, Soff-Cut's Ultra Early Entry saws can start cutting "as soon as you can walk on the concrete after finishing and not leave footprints," says Nabarrete. "Cutting any later than that leaves room for random cracking to form beneath the surface, causing unsightly surface cracks later on," she adds.
Green saws are also designed to "upcut" the material. "As you're pushing the saw forward, if the blade is mounted on the right-hand side, it is basically rotating in a counterclockwise direction," Tremain points out. Since green sawing is performed dry, this helps to keep dust from settling back into the cut. "If that dust gets back in there, it's green enough that it could go back in [the cut] and harden up."
The material to be cut and the desired cutting length generally dictate blade choice. Blade life is measured in inch-feet, or cut length times cutting depth. The amount of inch-feet you can achieve with a particular blade depends on the blade quality and the aggregate in the material.
"In concrete, you have different areas of the country that have different hardness of aggregates," says Tremain. In Kansas City, for example, material is fairly soft, allowing for good blade life in most cases. "If you use the same blade in Houston, TX, or someplace in the Florida panhandle, you're going to get 1/10th the life because it's real hard aggregate."
Blade suppliers can offer specific recommendations based on the inch-feet requirements and the aggregate in your particular region. Yet, it's also important to match the blade to the capabilities of the saw.
"One of the things to look for is the rpm listed on the blade," says Varel. "For instance, our saws run at 3,200 rpm. You want to make sure you have a blade that can run at 3,200 rpm."
Diamond blades should also be matched to saw horsepower. "If you take a blade that's designed for a 65-hp saw and put it on a 13-hp saw, the smaller saw doesn't have enough horsepower to keep the diamonds opened up and fractured to keep the cutting process going," Tremain explains. "Basically, what happens is the diamonds round off and the blade ‘closes up' and won't cut."
"You can only cut as fast as your blade allows," agrees Varel. "If it's slowing down, chances are you're taking so much horsepower, the belts are going to start to slip."