Grapple Saw Material Handling

What the Charts Can’t Tell You About Knuckle-Boom Cranes

The bark was rolling off everything.

On a residential lot on Aquidneck Island, Rhode Island, Darren Savadyga of Achin Back Tree, LLC, was working through a multi-tree removal in late spring, and the wood was pushing back.

It wasn’t because the picks were too heavy for the BIK Tree-Care Series TC-98/104 truck crane — but rather because the sap was running hard.

Turgidity — the seasonal surge of moisture and hydraulic pressure within the cambium that turns every piece into a wet bar of soap — was working against him. Each time the grapple jaws closed, the wood wanted to slip, roll, and twist in ways that a dormant-season pick never would.

“The higher the turgidity, the more it just has a tendency to roll,” Savadyga explained, watching a large section suddenly rotate a full ninety degrees from horizontal to vertical mid-lift. The bark had given way under grapple pressure like a sock off a wet foot. “Had that been a bigger diameter pick, and it rolls like that, you could have an issue.”

His adaptation was decisive. He would take smaller picks, no laterals, and nothing that depended on bark friction for control. Even though the machine was capable of more, the wood on that particular day in that particular season was not.

“You have to be aware of everything simultaneously,” Savadyga said. “It’s constantly just staying abreast of what’s going on, and where we’re at, and what we’re trying to achieve.”

One hundred and twenty miles away in Seabrook, NH, Doug Anderson of Doug’s Tree Service, LLC, had a different problem. Having recently taken delivery of one of the largest Palfinger knuckle-boom cranes in the country at the time, the PK 200002 LSH, Anderson and his son Bryan were working through the operational calculus that comes with stepping up significantly in machine size. Their job site had room, but the challenge was to know precisely and confidently what to do with it.

“A knuckle-boom crane will do the job of four bucket trucks,” Anderson said plainly.

This sounds a little like a sales pitch until you watch a two-person crew take down a sizable tree in an eight-hour day, stage the brush, and leave the cleanup for later.

“It works for some people. It doesn’t work for others. It just depends on where you’re at.”

A quick shift of the map to the southeast brings us to a lakeside property in New Milford, Pennsylvania, where Joe Pipitone of Top Notch Tree was doing what he had been doing for seven years: running a tight three-person operation with an Altec 175 knuckle-boom. This equated to time well spent processing trees efficiently and with almost no major mechanical failures across the entire ownership period.

“We’ve had almost no major issues as far as breakdowns or failures,” Pipitone said. “We are meticulous with the way that we operate the crane. We put it in the right position. We set it up correctly. We don’t ask it to do more than it’s designed to do.”

The result was seven years of use and zero workers’ compensation claims. The machine, Pipitone said, was worth every dollar.

THE OPERATOR’S MINDSET

What all three job sites made clear — independently and without coordination — is that operating a knuckle-boom crane in tree care is far more of a cognitive skill than a mechanical one. The machine is certainly capable. The question is whether the operator is capable of processing everything the machine demands.

Savadyga described the mental workload in terms that sounded more like air traffic control than arboriculture. Traffic management, hydraulic pressures, crew positioning, hose routing, boom geometry, load dynamics, wood species, seasonal conditions — every variable must be monitored simultaneously, with each cut introducing a new set of calculations. The crane may be doing the lifting, but the operator is constantly managing risk, efficiency, and outcomes in real time.

Anderson described the transition from smaller cranes to larger machines in much the same way. The physical controls and movements are familiar enough; in fact, their Palfinger moves nearly as fast as the smaller PK40 it replaced despite being dramatically larger. The challenge is not learning how to move the crane. The challenge is learning how to think with it.

As capacity, reach, and complexity increase, so does the consequence of every decision. The operator’s judgment becomes the limiting factor long before the machine’s capability does.

What changes is the margin for error, and the consequence of misreading a load.

“Side loading a machine on these is never good,” Anderson said. “Being able to know how a tree is going to react, where your cut point is going to be — it all takes years and years of experience.”

The manufacturers, he added, were reluctant to sell their largest machines to operators with fewer than five years of experience — not because the controls were harder, but because the machine could execute bad decisions faster and at greater force than a smaller one.

Anderson’s working rule of thumb: never run at more than 60 to 70 percent of chart capacity.

“We’re not overloading the crane, we’re not wearing it out, and we’re not taking the potential of something catastrophic happening.”

When Palfinger technicians performed a data download on their older machine, the history confirmed the discipline — nearly all picks ran at sixty-five percent of capacity or below.

Pipitone was equally direct on matching the machine to the pick.

“You want to take a bite of something that is yours,” he said.

Start with smaller sections when establishing a new position, increase piece size as geometry and confidence confirm it is safe to do so, and never cross into side loading.

“[Knuckle-boom operation] is something that you practice and you get in tune with — knowing where the dynamic energy is going to go, knowing not to take too big a piece,” Pipitone added. “The species of the tree matters tremendously. Different densities of the wood you’re going to be handling. That’s very important.”

THE DROP ZONE IS WHEREVER THE BOOM IS

One of the most important operational concepts Pipitone raised involves something that traditional tree care handles differently: the drop zone. In conventional work, the drop zone is roughly the drip line of the tree — the area beneath the canopy where material is likely to fall. With a knuckle-boom crane, the drop zone moves with the boom, and it changes every time the operator changes function.

“With the knuckle boom, the drop zone is wherever that boom is,” Pipitone said. “Or if he’s holding something, it’s potentially a drop zone. So, the entire radius is potentially a drop zone.”

One scenario highlights the risk particularly well. An operator completes the canopy work and shifts to loading logs from the ground. The crane’s working area changes immediately, with the boom moving into an entirely different sector of the job site. Without clear communication, a crew member who was previously in a safe location can suddenly find themselves standing in an active drop zone.

“You just changed the drop zone,” Pipitone told his operator after the transition happened without warning on one of their early jobs. “And we had a conversation about that, and he never did it twice.”

The corrective principle is straightforward: whenever the crane changes function or the boom moves into a new sector, the operator must communicate the transition to the crew before it happens. Final accountability, if material is suspended over a person, rests with the operator.

“If you pick up something and suspend it over people and it falls — it’s your fault,” Pipitone said.

Pipitone highlighted a related hazard: the sheer visual magnetism of the crane creates distraction risk for crew members running other equipment.

“I was mesmerized watching the crane picks,” he shared, describing a moment when his attention drifted from the loader he was operating. “My brain transferred from what I was doing to focusing on what I was admiring. And I actually backed myself into the tray of the chipper.”

The company’s standing rule: if you are moving the loader, you look in the direction you are driving. Full stop.

“If you want to take time to admire your beautiful crane and how great your operator is doing — stop and look. Then move forward. But never combine the two.”

WOOD SCIENCE ON THE JOB

None of the three operators treated load chart values as abstract numbers. In practice, the chart is a living document, updated continuously by the specific wood being cut.

Savadyga noted that species drives decision-making as much as weight.

“Oak has to be cut in smaller pieces due to weight, but also stronger fibers which will hold on and become impossible to break if the cut goes not as planned,” he explained.

Soft-tissue species release more freely. Storm-damaged wood is in a category of its own — storing energy in compression fractures and twisted grain invisible from the outside.

Hidden decay presents its own hazard. On one Aquidneck Island job, a cut went unusually fast — the saw moving through the wood without the expected resistance — until Savadyga realized the top side of the piece was rotted through.

“All your weight is on the top,” he said. “With the load, the lateral — it would spring up with the rot there. That would definitely cause a failure over the road.”

“If there’s a possibility, take two pieces,” Anderson said. “If you’re renting a cable crane you’re between two and three hundred dollars an hour. Your natural instinct is to hurry. And hurrying always gets you in trouble.”

Pipitone ran three separate load charts on his machine: one for static hook lift, one for grapple saw operations, and one for limb cutting — each accounting differently for dynamic movement.

WHAT MAINTENANCE ACTUALLY LOOKS LIKE

Pipitone offered the most detailed account of what a sustained maintenance commitment looks like across a full equipment lifecycle — and why his machine had delivered seven years of near-trouble-free performance.

“No matter what, you’re always going to have hoses that you need to be able to fix. Gaskets and O-rings that leak. Just basic stuff like that,” he said. “Cranes tend to want to leak, right, because there’s a lot of vibration.” The entire machine, from base to boom tip, is plumbed with high-pressure hydraulic fluid. The daily discipline begins there.

The steel hydraulic lines that run along the boom sections require daily attention.

“If you tweak a line and the lines rub each other, eventually you’ll rub a flat spot, and then you’ll get a pinhole and you’ll have a hydraulic leak,” Pipitone explained.

Every day, his operator extends the crane fully, watches the lines travel out and retract back in, and checks for any rubbing contact. Brass fittings that keep the lines in alignment are inspected and adjusted as needed. “That’s what keeps the crane boom going out straight and coming in straight.”

“If you’re going to commit to purchasing one of these, you have to be willing to turn a wrench,” Pipitone said. “You have to be willing to be able to change hydraulic lines. It’s not rocket science — but having them in inventory, like if we blow out most of the lines that we have on this truck right now, we can fix them with what we have on site.”

The grapple end of the crane sees the most flex cycles — the constant up-and-down articulation of the grapple head puts more stress through those hoses than anywhere else on the machine.

Carrying replacement hose inventory on site turns a blown line into a thirty-minute field repair rather than a towed crane and a lost day. Pipitone also pointed to the aftermarket plastic spiral wrap his crew uses to bundle and protect hose runs along the boom from wear and tear.

Wear pads — the Teflon and nylon guides that keep boom sections traveling straight and prevent metal-on-metal contact — are a scheduled replacement item, not a failure-response item. The outriggers are kept greased, so they move smoothly without clanking or scraping.

“Everything should go smooth in and out,” Pipitone said. “You shouldn’t hear clanking or rubbing or scraping or anything like that.”

The annual preventive maintenance cycle has not been skipped once in seven years. “Every single year for seven years, I’ve never skipped,” Pipitone said.

The cost is real. But the alternative is far more expensive: larger repair bills, unexpected downtime, and the operational uncertainty that comes from not knowing the machine’s true condition. For a business whose productivity depends on the reliability of a single piece of equipment, that uncertainty is simply unacceptable.

“You know, it costs a little bit,” he said. “But the small things like that go a long way.”

Both Savadyga and Anderson described similar inspection disciplines on their respective machines. The common thread: when one person owns and operates the machine, the familiarity that makes early problem detection possible is total.

“If you know your machine, you’ll pick up on it,” Savadyga said. “You’ll hear something instantly if you’re in tune to it.”

There is also the risk in larger operations where multiple operators share a crane without any single person taking primary ownership. When that intimacy is absent, the early warning signs get attributed to normal variation. The grinding that should have been caught as a minor adjustment becomes something structural.

“They look beyond things,” Savadyga said, “and then something starts crunching and grinding and they just keep running it.”

WHAT THE MACHINE ACTUALLY CHANGES

Step back from the operational details, and all three conversations converged on the same larger argument: the knuckle-boom crane doesn’t just change how tree work gets done. It changes who can do it, for how long, and at what physical cost to the people doing it.

“With the knuckle-boom cranes and telehandlers, you just increased your longevity,” Anderson said. “Whenever you want to be done — you can retire easily.”

The context was a conversation about experienced climbers whose bodies had been the limiting factor for decades. Mechanization doesn’t replace skill. It relocates it — from the tree to the remote, from the climber’s hands to the operator’s judgment.

“Look at how much work is getting done here, but how little labor is occurring,” Pipitone said, watching his operator process material from the remote. “I’m not sweating. In the olden days, we would have never got this much true work done in a day. I’d be dead. My feet would be screaming.”

Pipitone also pointed to an efficiency the machine delivers that extends well beyond the tree itself.

“The grapple cranes don’t just help aid in efficiency for taking the tree down,” he said. “They help with your logistics, and they help tremendously with your material handling — because you’re able to reach over obstacles, over a ditch or a wet spot or something that you don’t want to cross, grab the work and pick it up and float it over the air.”

His crew uses their chainsaw dramatically less than before. They pick up whole logs instead of bucking them into sections first. They load bigger material and transport bigger material.

“It’s just so much more efficient,” he said.

Asked what makes a good knuckle-boom operator, Anderson answered without hesitation:

“Take suggestions. Willing to learn. Humbles themselves.” He paused. “When you stop your brain from being open to listening to suggestions and advice, an accident is right around the corner.”

Pipitone put it a different way, describing the operator his machine had found in his own crew: a person who had done tree work by hand for ten years before the crane arrived, who understood tree dynamics deeply, and who also happened to have grown up with remote-control equipment — race boats, model aircraft, the kind of precision hand-eye coordination that transfers directly to a crane remote.

“He was like a duck to water with that machine,” Pepitone said. “He could just make the crane do what he wanted.”

On Aquidneck Island, the bark kept rolling. The picks got smaller. The tree came down.

That’s the job.

Tchukki Andersen is an ISA Board Certified Master Arborist, Certified Treecare Safety Professional, FAA Certified Drone Pilot and Operator of Uppinda Air Drone Services, based in Kittery Point, Maine.