Sometimes the choice is as simple as familiarity with the machine. "The type of chipper (disc or drum) is usually based on individual preference and years of operating that style of chipper," says Morey. "If a contractor is unfamiliar with the differences, then he or she should look at the type of material to be chipped."
He adds, "Disc-style chippers feature a faster feed rate, will chip larger material easier and will consume less fuel than drum-style chippers. A drum-style chipper features wider infeed openings and will collapse limber material more efficiently than a disc-style chipper."
The reduced weight of a drum-style chipper can also be an advantage. "Drum-style chippers allow for chippers to be smaller and lighter in weight," says Roorda. "With the price of fuel increasing, the size and weight of the chipper being pulled will have a huge impact on fuel costs day in and day out."
William Smith, director - service, parts and warranty, RSC Equipment Rental, notes, "Drum machines have increased in popularity in recent years due to the fact that they are, in most cases, more compact and easier to tow. At RSC Equipment Rental, we recognize that and rent drum machines to our customers."
"Regardless how you intend to use the chips, make sure the chipper you rent has a chute that can be rotated 360° to accommodate any option," says Frazao. "These chutes are now standard on most chipper models."
Roorda points out, "The majority of the time, a chipper will be blowing chips into some sort of container/chip truck for the chips to be hauled away. There are certainly circumstances where the chips can be broadcast over the ground to either leave lay or be collected by a loader."
Do your homework to find out if there is a market for the chips you will produce. "If there is a local market for chips, most contractors will try to blow them into a chip van of some kind," says Showers. "Disc-style and drum chippers are equally able to do this."
Consider how easy it will be to completely and efficiently fill the chip truck. "If a contractor is going to collect the chips, we recommend renting a piece of equipment with a hand crank or hydraulic swivel discharge and hand crank, height-adjustable discharge chute," says Morey. "These features will allow them to fully load their chip trucks, reducing trips to the dumping site. With the price of fuel, these features will save money."
Towable vs. self propelled
Towable chippers are the most popular on the market. "Towable chippers work great for almost any application," says Morey. "However, if you have a large land/lot clearing job or soft soil conditions, a self-propelled chipper would save time and money. You can take the chipper to the trees and eliminate the need to forward or skid material to the unit. It also will travel over uneven or soft terrain, allowing it to access areas not accessible by towable units."
Showers adds, "Towable chippers are most often preferred in residential lot clearing, etc. Self-propelled units were originally designed for right-of-way work and are useful anywhere the towing vehicle would not be appropriate, or in applications where you do not care if you capture the chips."
The choice really depends on what types of work make up the bulk of your project. "For customers concentrating on tree trimming and even take downs, a towable chipper probably best suits their line of work," says Roorda. "For customers who are working off road and in hard to reach areas, a self-propelled chipper best fits their needs. Any time a chipper needs to be moved repeatedly within a small area, a self-propelled chipper would be a better choice, as it can easily maneuver around and through obstacles."
The removal method for chips can also have an influence. "If you can position a chip truck to catch the chips, then a self-propelled unit may not be necessary," Smith states. "But if you are doing right-of-way clearing or site prep and can leave the chips behind, self-propelled may be the way to go."
The finer points
Certain features, such as hydraulic feed systems, can ease chipper operation. "Hydraulic feeds are becoming increasingly popular, because they offer the dual advantages of reducing operator fatigue while enhancing safety," says Frazao. "Both attributes improve productivity."