Truck / trailer mounted crane

[cstamm81]

Hi guys, I thought I壇 throw this out there and see if anyone has any experience with a project of this nature. I知 collecting parts to build a crane attachment, primarily for picking up large rounds of firewood and short logs. I scored an old school Blackhawk engine crane the other day, rated at 2k lbs, with a manually extendable boom arm.

The plan it to replace the porta power driven cylinder that raises and lowers the boom with a 2 way cylinder, powered by a hydraulic power pack. Then, I値l mount a winch on the top of the boom, and weld a sheave on the end of the boom arm.
Ideally, the crane would be able to be mounted to a trailer or the bed of a truck. Where am I struggling is trying to come up with an easy, safe way to allow the crane to rotate. It appears the cheap truck cranes simply rotate on a pipe inside of another pipe so to speak. I feel like with a heavy load, there痴 going to be a lot of friction to rotate the crane, especially if the ground is uneven.

I see heavy duty turntables out there, but I can稚 imagine they are designed for anything but a load pushing directly down on the plate. With a tall crane, there痴 going to be a lot of leverage and this force pulling sideways on the base. Ideally, I could electrically or hydraulically rotate the crane, but I致e yet to come up with an easy / cheap to use way to accomplish this.

Anyone have any experience with a project of this nature? The Chinese made cranes available at say harbor freight look cheesy to me, and the next step up in quality gets expensive really fast. Hoping to build something robust and very capable for much less. Thanks in advance.

 

[hosspuller]

Consider a wheel bearing capsule or a stub axle as a pivot. Has bolts / studs to attach to a base. Designed for an over hung load.

Unless you build a leveling mechanism, it will be still be hard to rotate since you'll be pushing a load up hill.

Excavators have much more house rotating power than a crane for that reason.

 

[zzvyb6]

I have a spare turntable that was intended to be used for my JLG T350 trailer mounted boom lift. Normally would be run by a hydraulic motor. Worm drive.

I'm in S.E. Michigan. That would be an 8 hr. drive one way for you !

It might be shipable through a truck Carrier. Solid steel, Heavy as ....

 

[cstamm81]

Good idea with a stub axle. I would want to come up with a way to lock the pivoting portion in place at different points in the rotation, mainly for safety reasons. A heavy load could swing wildly given the right situation. I had a hair brained idea to see if I could use a small electric winch, stripped of its wire rope, drive a chain on a sprocket, sprocket on the pivoting mast. If possible, I feel this could be a cheap and dirty way to gain per tarp around, and a built in brake.

 

[cstamm81]

Could you send me specs on the turntable? Does it have a manufacturer and model number? I壇 be curious if it would be a fit for my project.

 

[zzvyb6]

Could you send me specs on the turntable? Does it have a manufacturer and model number? I壇 be curious if it would be a fit for my project.

You can see all the parts in the turntable in the JLG T350 Illustrated Parts Manual available on line on the JLG site.

 

[plumbstraight]

I built mine and used the cabguard as part of the anchor. I built the bed so it heavier than some factory built rig. I did put a brace from the bed to the top of the guard so it is triangle for strength. It has an 8ft boom with a 3500lb atv winch and I use two pulleys to slow the lift down. I pick my quad and motorcycles up to load. Have used it for loadng different things.

One thing to put out there though, when lifting over the side realize that swinging the load on the truck will take some effort as the truck will tilt toward the load. I lift in close as I can to the side to help alleviate some of this.

 

[4570Man]

I have an old backhoe boom that I was considering turning into a crane. It wouldn’t have needed a turn table. I think the backhoe would have had enough movement to work.

 

[cstamm81]

Plumbstraight, any chance you could attach pics of your crane? Very good point concerning lifting over the side.

 

[cstamm81]

4570Man I too had considered using a backhoe boom to make a trailer mounted crane. I致e been thinking about building some type of crane for years. I was always hesitant due to how darn heavy it would be though. Other than that and having a limited reach given the weight, I can稚 see why it wouldn稚 work.