Boom crane grapple saw - GIF

[ToolTalkBot]

Boom crane grapple saw.





Previously:

Crane drops antenna tower section
Crane hits power line
Crane lifting billboard topples over
Port crane demolition fail
Self-erecting tower crane
Shipyard crane collapse

[metric_taper]

A few years ago, I got a quote to remove what remained of an Oak tree, that was right next to my two story garage. At it's peek is 30 ft. to the ground. The 'arbor-ists' were going to hire a huge crane, and lift it from the street, 115 feet to where the tree was. A log, 25 ft. long of Oak. Not real old, less then 65 years, and 3ft diameter at the ground root entry. That was $13K estimate.
If they did not damage my property, which the second floor garage is 1200sqft. and the county would never let me rebuild it. So I built a scaffolding out of 20ft 2x4 Cheap SPF I was using for concrete form boards over many years of storing out of the weather. The scaffolding had floors every 7 ft. up around the 4 2x4 posts. I had guard rails as well. And Used 3 (three count) of 18" Oregon brand electric chain saws. They all failed the same way, the oak cutting had all sorts of shock that soft wood would not transmit to the wound rotor. The failures were from winding shorting. Overheating they had protection, but I get them long cool off periods, as that's the most common failure of electric chain saws, duty cycle, and long cuts, that are heaving exceeding the current input ratings long term. Those 9-12" electrics that are less then $40 are marvelous. And I've put 20" blades on them with baby cuts to slice thick logs. Those 9" pole saws Harbor freight have, you can modify a 20" chain blade for the missing hole, and from a safe distance, cut off branches, as I had to do that. And the pieces were roped off, as I saved my self $13K, minus 3 $85 chainsaws. Oh, and I broke a $250 window, by dumb attack. Twice.

[Harvey Melvin Richards]

Here is a video of one in action. Amazing machine, only $800K.