Jib Crane

[Panovak]

Ive done some digging and haven't seen anybody use a larger/ heavy duty jib crane to move / roll logs and large slabs around. I have a fully manual mill and I mill almost exclusively alone and moving heavy stuff around is probably the part I least like about milling. It would require a significant concrete base but thats easy relative to a gantry system. I was thinking mast would be on one end opposite of the business end of the mill. Thoughts?

[47sawdust]

Don't know what kind of mill you have,but this is an LT15 on steroids.https://forestryforum.com/gallery/index.php?cat=32340

[DanielW]

If you had a bandmill in a stationary location, didn't mind a little time strapping up the logs, and weren't doing large/heavy logs, a jib crane sounds like a good idea. I think there are a couple of reasons you don't see it done too often, however:

i) Time spent strapping logs. This applies to all overhead log loaders/cranes without a grapple, and why you don't see them too often: If you're running in a high production environment, the time spent slinging, hooking, chaining, or strapping a log/cant, getting the load centered, etc., is not insignificant. For a smaller operations where a few minutes spent strapping each log isn't a big deal, a jib crane might be ideal. But then, for a smaller operation, the cost of a suitably-sized jib crane (and the appropriate concrete) might not be justified. For an operation large enough to justify the crane and concrete costs, there are probably other (and faster) handling methods available in the same price range (hydraulic log turners, live decks, etc.)

ii) Crane Size: A 30" diameter, 16', hardwood log could be well over two tons. A two ton jib crane is a honking big and expensive unit - especially with the kind of reach you'd need to load logs from the other side of the mill. The cantilevered nature of jib crane means that the boom is a lot larger than the beams for a gantry-style crane. The short (8' reach), two-ton jib cranes in our shop use a 12" I-beam for the boom  with hefty brace arms and tie plates. The long 2 ton ones (16' reach) use 18" I-beams for the boom. That's a hefty amount of steel. And as you pointed out, the concrete concerns are significant. Not only do you need a large/solid/deep pier to carry the vertical load, but you need it well tied to a thick reinforced slab with suitably compacted substrate to handle the large overturning moment, whereas a gantry crane has no overturning moment and can spread the load, so a much thinner slab is suitable.

Take a look at this link for what's probably a suitably-sized jib crane: https://cranedepot.com/2-ton-h-series-floor-mounted-jib-crane/

[barbender]

 I removed one post- links to CL ads are not allowed, and photos must be in your gallery.

[barbender]

 I've always been fascinated with the gin pole, and swinging boom derrick style cranes made with timber and rigging. I think a properly constructed swinging boom would be very handy at a mill. There is one out at the Western Minnesota Steam Thresher's big sawmill setup that is used to pull logs in from the mill pond.

There's a downloadable US Army rigging handbook that shows how to construct many useful lifting devices.

[Panovak]

I see 1 ton jib cranes with a 10' reach around me for less than 1k. I wouldn't attempt anything larger than that anyways.  I think I'm going to give it a go. I'll weld on a some thicker plate steel to bottom plate to reduce torque on the mast. In my mind it's easier than a gantry.  I need more mechanical advantage around the mill.

[Jack jr]

Bit late but I built this on the back of my ute, it's limit is around 1/2 ton but that's only because of the vehicle it's on, costs nothing compared to a crane. Cheers Jack jr