Clearwater Yarder, Page 1

Clearwater Yarder

Concept

Where terrain and soils limit conventional ground skidding, advanced cable yarding systems-like the Clearwater Yarder-offer a solution for removing small timber or dead wood. The Clearwater Yarder is a lightweight, three-drum system that makes harvesting small material practical.

The Forest Service developed this yarder concept for the Clearwater National Forest in Idaho to remove dead wood from areas unsuitable for broadcast burning.

Since August 1977, the Clearwater Yarder has been used at sites in five Western States. It has operated more than 1,600 hours without major breakdown. A second Clearwater Yarder has been operating in the South since October 1979.

Daily production has ranged from:

95 to 174 tons of slash
68 to 100 cords of firewood
8,000 to 12,000 board feet

Features

Designed to be built in small shops using standard parts
Design complies with accepted logging industry safety practices
Easily mounted on a suitable flatbed truck or trailer
Line speeds to 1,000 feet per minute
Each level-wind winch can be powered independently in both directions or free wheeled or braked
Mainline and haulback can be hydraulically interlocked
Hydrostatic transmissions balance load and speed at maximum engine power
Remote control operation for safety, improved visibility, and minimum crew size
Slack pulling capability when operated with Christy carriage
Designed for rapid, simple setup

Drawing of the Clearwater Yarder. The dimensions of the platform are 5 and 1/2 ft wide by 12 feet long and 5 feet deep with a boom length of 34 feet.

Specifications

Overall Weight:
13,500 lb

Engine:
Detroit Diesel Allison
3-53N rated 97 BHP @ 2,800 RPM

Hydrostatic Transmission:
Dynapower pumps with Hagglund & Soner wheelmotors, 300 rpm maximum drum speed

Brakes:
Drum type hydraulically operated

Live Skyline:
800 ft of ½-in cable
7,500 lb maximum line pull
0-500 fpm line speed

Mainline:
900 ft of 3/8-in cable
3,500 lb maximum line pull
0-1,000 fpm line speed

Haulback:
1,800 ft of 3/8-in cable
3,500 lb maximum line pull
0-1,000 fpm line speed

Mast:
10-in by 10-in by ½-in wall square tubing
170° fairlead swivel
Hydraulically raised and lowered

Control:
12-volt dc over hydraulic