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Nicholson A7 Debarker

Nicholson's new completely enclosed A7 debarker incorporates design elements with its popular A5 and A5A models, but with changes that include improved debarking technology, increased performance and durability and easier maintenance.

The key to the machine's added performance capability and reliability, says the company, is a new-design perimeter frame that provides higher feed speeds with more reserve strength than the previous single-column design. The feedworks drive has been simplified and strengthened by eliminating the gear reducer and a roller chain. Belt drive is now used to transmit power directly to large spur gears.

Direct service access represents a major change in preceding designs. Direct access and pre-solved maintenance sequences are provided for each component. Full height sliding doors give top to bottom access to feedworks drive bays. Retrofitting is easier in tight installations (the A7 has the same footprint as the A5 and A5A). The top panels over the feedrolls are removable for quick roll changes.

A new full-function roll control providing several feeding modes is standard. The air control circuits are now split into individual infeed and outfeed panels for faster response, simplicity and better roll access. The air tanks and air cylinders are easily accessed but located inside the debarker to protect them from dirt and damage.

Training Centre Suppliers

In an article on a new value-added training centre in Abbotsford, BC (LSJ, Dec/Jan), computer gremlins contributed to several typos in a paragraph describing suppliers participating in the venture. For the record, suppliers involved mentioned in the article are: Newman-Whitney, Dimter, Western Pneumatics,

Sisu Valmet

Sisu Valmet has an-nounced a new thinning head, the 945. The company describes the unit as an evolutionary successor to the 942, but with larger opening dimensions that provides a cutting diameter of up to 550mm/22''. A new saw box design has a conical-bottom profile for added strength. The head's compact size enables the operator to handle crooked stems or unusual trunks at top speed, says Valmet.

The 945 grips a tree faster and its built-in "smart'' feature makes the saw retract the instant the cut is completed, further saving time and preventing damage to the chain.

Elevated positioning of the electrical control unit and valve package enables eye-level servicing. Servicing is reduced as fewer hydraulic cylinders are used to perform head functions; the cylinders are interchangeable.

The 945, as with the larger 960II and 965 models, employs Sisu Valmet's patented cam-curve suspension system and spring-loaded delimbing knives. The head uses five delimbing knives to completely encircle the stem. The cam-curve design cradles and feeds the stem via support of the roller wheels. Cam-curve extends the life of the feed rollers and allows the operator to maintain consistent feed rates for large-diameter stems down to a minimum of 35mm, says the company. The spring-loaded delimbing knives minimize friction on the trunk, which maximizes delimbing force.

"The industry people took the position that it was none of their business," says Buchanan. "It was a commercial transaction. The government decided to have a look at it and study it, and that's what the Jacques Report was basically all about."