Two Log Cart Designs from Canada
from issue: 26-1
Two Log Cart Designs from Canada
by Dann Harris of Hanover, ON
The problem horseloggers face is reducing skidding friction yet maintaining enough friction for holdback on steep skids. The cart had to be as simple and maneuverable as the basic two wheel log arch which dangles logs on chokers. These carts seem to have a high point of draft, high center of gravity and tongue slop that can be counter productive while only providing enough lift to reduce friction marginally. We wanted it to be light, low, with no tongue weight, no lift motor to maintain, no arch to jam up and throw the teamster in a turn, and a low center of draft.
The sled design has been around for centuries — pretty hard to improve on using the front bunks of a sleigh to elevate the butt ends but how does one load it? Just putting a longer handle on my cant hook didn’t seem practical. The sled needed clearance for stumps and rocks and to avoid “bulldozing” in certain snow conditions. The cart and sled we built use similar loading, skidding, and unloading principles and can be used to move tree length logs from the stump or log length after they have been ground skid and bunched at the trail.
A log is lifted with a hand pumped hydraulic jack; log tongs attached to the boom raise and pull the log up and over the roller bunk.
The jack is released and a chain chokers the log through a ring on the frame that keeps the log centered in turns, and on sidehills, and attaches to a quick release at a point close to the line of draft. Both units can accommodate more than one log; both have adjustable mast and boom to match the force of the lift with the size of the log. Neither unit is intended for skidding with logs hanging from boom.
At the landing or yarding area the chokers are released, the horses walk forward and the logs roll off the bunk.
The cart can be narrowed to 60″ overall or widened for multiple logs by moving spacers; the cart can roll into a pickup for transport.
The walking beams add fore and aft stability over the 2-wheel carts, plus the “walking” action smooths the ride as well as the draft on the horses collars. A third walking beam mounts across the front of the cart – this allows the complete weight of cart and log to be carried on the wheels, not on the horses’ necks since the tongue is vertically hinged. The walking beams are hinged to prevent logs from binding in turns but have locks to lock after logs are dropped at landing so cart can be backed as easily as a 2-wheel cart.
The cart has a Scandinavian sling-style seat which gives more stability to the teamster than the conventional implement seat because the teamsters’ legs are fully extended and locked. The frame has 15″ of clearance and the tongue is removable with one pin to switch to an offset tongue for three abreast.
The sled operates similar to the cart. It has 12″ of clearance and unbolts for transport. To keep tongue weight to a minimum, cable is used to strengthen it for turning under load.
This is the present state of development of the two units, although we want to develop the cart further. One hub is machined to accept a sprocket to drive a hydraulic pump. Plan is to mount a hydraulic accumulator, cylinder and hydraulic log grapple. With this the choker chains would be eliminated, the cart would be heavier, more expensive but eliminate the breaks the horses get while the teamster hoists the logs up with the present low-tech hand pump although the teamster could lower, then raise a log going over uneven ground to make the cart even more stable.