|Classic Heel Boom loader|
|Ross equipment was a major logging equipment dealer in Portland who also manufactured some speciality logging equipment|
Featured here is a classic American Heel Boom Log Loader. Other than the boom, the base machine was identical with those equipped with a lattice boom for construction lifting, and with a shovel front for digging. Indeed in this generation of equipment loggers came to call their loaders a 'shovel' even though they obviously were not equipped for digging when configured with a heel boom.
The grapple dangled from the elevated end of the boom called a 'grapple riser'. This provided space for the grapple to 'disappear' when the log was lifted tight against the boom. A cable grapple is simply a pair of jaws suspended on two cables. If you hang it on one of the cables it hangs open, and if you hang it on the other cable it hangs closed. The operator with a clutch lever in each and and a brake pedal for each foot would adjust the lines to make the grapple work. Sometimes a 'tag line' was provided so you could rotate the grapple as well. The general idea was to open the grapple, drop it over a log and then lift with the grapple close line. This would grab the log, and if you did it right--you grabbed the log around 10 feet from the end (assuming a 30 or 40 foot log). The short end of the log would then come up first (the end closest to you) and you kept lifting until it hit the bottom of the boom. Then you kept on lifting thus 'heeling' the log under the boom. This provided 2 points of contact for the log discouraging it from swinging about, as you had ahold of the log in one place and it was prying or heeled against the bottom of the boom.
Beginning in the 1960's hydraulic machines began to replace the cable machines for loading logs and it is easy to understand why. Most log loaders today are based on excavator chassis, whereas these machines were based on a shovel or crane chassis with just a different boom.