Gin poles

[afroman006]

I want to make a set of gin poles to mount on the back of my truck for picking heavy **** up. I have seen a few pics like AKfabshops but nothing up close and am curious as to what other people have done. I have a heavy pipe rear bumper and was planning on welding hinge tabs to the outside edges of the bumper, so they will not interfere with the tailgate opening and closing and using around 7' poles, so I can mount them inside of my longbed when they are not in use, and so I can have them with me all the time. I need to work the geometry out to see if they will be long enough, I doubt it so if they arent I'll have to come up with some kind of two piece system.

To hold em up, I was thinking of making a little "hitch" that has a grab hook and small ATV winch mounted on a stub so I can stick it in my gooseneck hitch. The way it would work is I set the poles up, use the winch to lift them to the desired height, then attach a chain to hold them at that height and use the winch to lift whatever needs lifting. The only part I really cant figure out is the pulley at the top. What do people normaly use? I was thinking maybe a plain snatch block but that would waste a little bit of lifting height. Anyone know where I can get a large pulley for relatively cheap?

 

[BadDog]

Not much to offer on your question except a warning. "Gin poles" can be very, very dangerous if your not careful. Loads, leverage, and resulting failure can be unexpected and catastrophic. More than one skull has been crushed or back broken by failed rigging on a gin pole system... I've used them myself and will continue to do so if needed, but I HAVE had a chain anchor that was not properly secured (don't trust someone else helping out!!!) come loose with an engine+tranny hanging from a 20' boom. I heard the "BAM!" as it came loose, looked up and saw the boom coming at me, had just enough time to start moving to the side while I instinctively leaned my head away, just as the boom came diagonally down to graze my ear and then on to break my collar bone along with massive bruising. Easily could have been much worse. There is a reason that crane/lift rigging is very closely controlled and carefully engineered.

Just be careful.

 

[jarheadk5]

Question - are you wanting a "gin pole" or an "A-frame"?

As I understand it, a gin pole is a single vertical pole, whereas an A-frame is two poles forming a triangle, secured together at the top. I'd definitely go A-frame if it were my project; seems a whole lot safer (and easier to rig/more tolerant of misrigging) to me...

 

[afroman006]

Yah A-frame. I've always heard it called "gin poles" but thats not really that important.

 

[diesel4me]

Bad dog is right...BE CAREFUL!!...but cranes are COOL!

I agree with Bad Dog's warnings!..though the addition of a small crane type hoist has by far been THE most useful thing I ever built and used on my truck,as far as loading and unloading heavy items,it has proven to be the most dangerous thing I've built too!...

I've had some VERY close calls with my crane,and I'm very cautious when using it too!..and a few times I have crushed and pinched fingers,cut them on the winch cable--not to mention FAILURE of the cable,and having it whip back and nearly take out an eye,slice you like a razor,or worse yet,having the load DROP ON YOU!..

There is nothing like having a heavy load pull you along with it and drag you right into the truck bed with it,or pin you between the truck bed and the load..

I've had to RUN a few times while trying to turn the crane in the direction to get the load into the bed,and because the truck wasn't on level ground,once I swung the crane a bit,the pendulum effect took over,and it came flying back the wrong way..nearly twisted my arms off trying to hold it,and I finally had to just say "F" it,and let it crash into the side of the flatbed!..I'd have been jelly had I not moved quickly enough!..

Its very important to use a jack stand or similar device( I used a trailer toungue style jack),under the frame of the truck under the crane when using it!..if you dont,your springs will be flattenned as the winch picks the load up,and its very possible to bend the frame!..
I had the front left tire OFF THE GROUND a few times when I forgot the stand,(or was too LAZY to set it up!)..and the frame rails were 2" higher on the opposite side from the crane when I scrapped the truck finally,all rotted to death..the jack stand also prevents the load from swinging the wrong way by keeping the truck on a level keel...

For all the work and engineering involved,its easier to just buy a crane from a place like Harbour Frieght or Northern Tool..or use an engine crane by making a pipe pedastal base to slide the boom and piston over to make it swivel,and remove the boom part from the usual "legs" and wheels it used formerly..

I scored a large pulley for my crane at a junkyard where an old drive on 4 post lift had been scrapped..it had heavy cast iron sheaves,like a real crane would use..old Holmes type wreckers used them,and you could likely get "Rope Sheaves",as they are called when made for hoisting,at an industrial supply house..or a place that sells tow truck supplies...the junkyards are much cheaper,and they aren't that scarce to find..

If your lifting 1000 lbs or less,just about any cast SOLID (no spokes!) "V" belt pulley will suffice..my homebuilt gantry crane with a winch(former city park swingset made of schedule 40 ,3" pipe!) has an old wheelbarrow 8" RIM used as the "sheave" to guide the winch cable up and over to the center.(and an ordinary cast iron 2" pulley in the center)...despite the rim being rather thin gauge,its never showed any sign of strain or failure,even when I picked up the flatbed weighing 900+ pounds off one of my pickups..you could use just about any steel rim (like a "doughnut" space saver,etc),and weld a plate like a big washer on each side of the rims center,with a pipe for a "bushing",if you dont want to search for a "real" rope sheave.....

I still have my crane,and the flatbed its mounted on..but its now mounted on a truck frame I converted to a trailer..I liked it much better when it was on the truck itself..it sucks trying to manuver a truck AND trailer into tight places..I may remove the crane and mount it on my 82 K20 Stepside,between the rear bumper and fender,outside of the box..either that,or make my "spare" engine hoist I had given to me when a friend moved into a crane,using an old Dana 44 front hub/spindle assembly for the "swivel" base..

I had thought about installing an old home built "wrecker" A frame I have stashed out in the woods,but I disliked the idea of having it hog all the bed space,and having to pull a 300+ pound behemoth out every time I want my bed empty again..plus I'd need a huge winch,and I dont have one..

I have a 500 Caddy motor/th400 in my shed,and a 1000+ lb Air Compressor that I need to move..both are up for sale,and there isn't much of any other way to get them out from where they are now stored if someone does buy them..so I guess some heavy lifting and labor is in my future..sucky part is I have to use another crane,to LIFT the other crane!..

 

[bgreen]

here is a current discussion on gin poles that you may find usefull. http://www.alaska4x4network.com/showthread.php?t=16070