Although Wood-Mizer is probably best known for its ‘Orange’ range of LT mobile and stationary sawmills, the company also manufactures an Industrial range for customers with larger volume and higher productivity requirements.
One of the most recent additions to the Industrial range is the WM3500, an impressive horizontal narrow band sawmill able to handle logs up to 1m in diameter and with many features to improve productivity and reduce labour requirements.
Although the WM3500 is one of Wood-Mizer’s latest machines, it has a long and proven heritage. It is based on the smaller WM3000 (previously the LT300), which has been a highly successful machine worldwide. The LT300 was introduced in 2003, which means that its performance in key areas of speed, productivity, reliability, cutting quality, ease of use and operator comfort have been evaluated through many installations over many years, and enhanced as a result of Wood-Mizer’s active ‘customer feedback’ system.
Further significant improvements have been made with the WM3500 to increase the functionality and performance of the sawmill. The ‘throat width’ (from sawguide to sawguide) of the sawhead is 150mm (6in) wider than on the WM3000 and therefore takes a longer bandsaw blade, which means the new machine can handle larger logs and the cutting process is easier and more productive.
In addition, the hydraulic system for positioning logs on the deck has been completely redesigned, with a more powerful pump
motor that increases operating speed of the turner, clamp and side supports by 25-40%. The hydraulic system also now offers two speeds, with the operator using a footswitch to choose between ‘fast’ mode for rapid initial positioning, and ‘slow’ for fine control over accurately orientating and leveling the log on the bed.
The WM3500 combines the functions of a headrig for primary log breakdown and a resaw for cutting finished boards. The operator station – with comfortable swivel chair and ‘joystick’ controls mounted on the arms – is positioned at one end of the mill, with the head sawing towards the operator who has an unobstructed view of the log. As the head returns after each cutting stroke, special arms mounted on the rear of the head automatically remove the cut board onto an outfeed conveyor and air jets clean any debris from the top of the log, so the operator can clearly see the top surface and make grading decisions.
A built-in laser shows the cutting line, and the Setworks control allows cutting lists to be pre-programmed, with the head
adjusting automatically for each pass to cut the required thickness of board. A new ‘cruise control’ allows the operator to pre-select the maximum optimum cutting speed for achieving high quality sawn timber depending on the size and condition of each log and the finished board dimensions. This function then automatically sets that speed for consistent cutting of the whole log.
The narrow band sawblades and advanced guide system – which comprises blade lubrication ports, heat-treated rollers and double block guides – reduce energy requirements by allowing accurate cutting at speeds similar to those of other mills requiring two or three times more horsepower and therefore higher electricity consumption.
Narrow band thin-kerf sawing technology not only allows less costly equipment, less complex installation and lower energy bills, it also increases yield by cutting ‘less sawdust and more boards’ from each log. Achieving maximum yield from the log and reducing waste makes economic sense for the sawmiller and is also environmentally responsible – something that is increasingly important to customers.
The WM3500 is available with a wide range of material handling options including log ramps and outfeed conveyors. Another new development on this machine is the optional Pantograph system for routing the electrical cables that connect the control panel to the sawhead and other working parts.
Traditionally, these cables were enclosed in a ‘cat track’ that ran along the machine bed. Although a well-proven system, some of the sawdust, chips and bark offcuts produced during sawing can fall onto the track, which has to be cleared out from time to time.
When running at higher production levels such as the WM3500 is capable of, this clearing out has to be done more frequently due to the increased volume of dust and chips. To overcome this, Wood-Mizer engineers developed the Pantograph, which comprises articulating arms that hold cabling above the machine where it cannot be contaminated by falling debris.
For still greater productivity and for customers who want to upgrade or start-up a complete sawmill operation, the WM3500 can be installed as part of a complete package of machinery, including, for example, a horizontal multihead resaw for sawing cants from the WM3500 into boards of various thicknesses in a single pass, and the EG edger or multirip for producing square-edged wide boards or multiple narrow boards.
The WM3500 cuts fast and loads logs fast, and delivers accurate sawn timber with a quality surface finish, with maximum yield from each log. It represents a significant step forward in Wood-Mizer’s development of Industrial machines and enables sawmillers to become more efficient and more productive, while reducing operating costs.