Knuckle boom crane vs winch? HELP!

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I have a 1998 international 4900 crew cab, it has a utility body with a 42' national 5 ton winch crane mounted between the cab and utility body.  I wish I had a better pic, but you get the idea.  I am trying to figure out if it is worth swapping to a knuckle boom or trying to lower the existing crane.  I currently have a 13' clearance height.  I can loose 8.5" if I remove a spacer and shorten the outriggers.  I have the ability to do this, but want to hear your thoughts about knuckle booms.  I have never used one, but they seem to have much heavier capacities.  I can pick 1800 pounds at 42' and zero degrees. Attached Images
Reply:Not being a crane op by any stretch of the imagination but I did run one many years ago before regs came into effect. I found the knuckle boom harder to accurately place objects as opposed to a regular cable. Saying that, it could be the operator :-)......Mike
Reply:Not a crane operator myself, but spent a lifetime rigging. One time I got roped into using a knuckle boom. Estimator said he left out the cost to rent a boom truck, so he swung a deal with plant management to borrow their knuckle boom. I had to install spiral stairs around 80-feet diameter tanks. Just looking at it from a rigger's standpoint, never again! Don’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:from a repair stand point I like knuckle booms. You cannot push or pull with a cable. I like how maneuverability they are in tight areas.thermal arc mst400, va4000 feeder, lincoln 175 min, victor torches, miller s32p feeder, air arc k4000 for work.
Reply:What are you wanting to do that your winch can't do?
Reply:What is your application? That is key. A knuckle boom and a standard hoist crane are not really good for the same things. In a lot of ways, a hoist unit is safer (with experience, it is less likely to roll over or snag a load, as the angles and directions of motion are simpler), but a knuckle unit can reach to places and make motions a boom crane can't, including push and pull a load.
Reply:Originally Posted by enlpckWhat is your application? That is key. A knuckle boom and a standard hoist crane are not really good for the same things. In a lot of ways, a hoist unit is safer (with experience, it is less likely to roll over or snag a load, as the angles and directions of motion are simpler), but a knuckle unit can reach to places and make motions a boom crane can't, including push and pull a load.
Reply:Scott pushing and pulling inline with the boom you can get away with a lot, it's side loading the boom that will bite you, in a big way!Don’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:Side loading is a definite no-no. Real easy to damage a shive, pop a cable out, bend the stick, damage the swing gear, and so on.  Pushing and pulling in line with the boom is done, but is discouraged for a bunch of reasons, top among them being the change in effective boom angle, which effects stability, and the difficulty in controlling loading when dragging-- a little hang up and the load jumps, a slick spot and you go slack-- and when a load comes into suspension. If the load comes up swinging, especially if it come up uniformly (the lift point wasn't over the center of mass), the loading due to swing can end up being side load or destabilizing load due to change in effective boom angle.
Reply:I am really looking at the pros and cons of the knuckle boom.  I am trying to get my overall height down,  I can remove the spacer under the boom and shorten the outriggers, but it still wouldn't be as low as a knuckle boom all closed up.  I have never used a knuckle boom and I have another 90' boom truck, so this is my smaller one.  I think going through the process of removing the spacer would be as much work as putting a knuckle boom on it, so I wanted to get some opinions from users.  I never thought about using the knuckle boom to push or pull something.  Can you exert force on things like the way you could with an excavator bucket?
Reply:average truck knuckle booms wont have that kinda reach nor that capacity even at their shorter reach, but are very maneuverable and adaptable especially if a winch is added. If you are gonna fold a knuckle up for storage and transport, it sure takes a little practice. Last time I worked on one that was folded up I like to never got it straightened out. Most of my customers carry them straight out in a overhead cradle.
Reply:if you ever had to reach over a wall or down into a hole then a knuckle boom wont do you any good.     I will warn you with every ounce of my being if you go to modify that boom without an approved engineers stamp and drawings GOD HIMSELF couldn't help you if anything ever happens while your using that crane.    Not to mention anyone that would buy it used from you would be insane.Vantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:Originally Posted by Dualieif you ever had to reach over a wall or down into a hole then a knuckle boom wont do you any good.     I will warn you with every ounce of my being if you go to modify that boom without an approved engineers stamp and drawings GOD HIMSELF couldn't help you if anything ever happens while your using that crane.    Not to mention anyone that would buy it used from you would be insane.
Reply:And im telling you, it will need an engineers stamp for any modification you do in order to pass your annual osha inspection.   You are getting it inspected annually right?I'm not saying you don't have the skills to pull this off im letting you know what you need in addition to those skills.Vantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:Every crane we have ever built, just needed to pass an inspection.  The one we had the most trouble with was mounted on an old FWD truck, it only had 4 tires.  They refused to pass it until we did some lift testing.  After that they were fine with it.  Keep in mind, we are not modifying the crane, just the outriggers, if you are on an uneven surface and you use any cribbing to level it out, you are modifying it as well, do you get an engineer to sign off every time you use cribbing?
Reply:No but i do get an engineers approval and stamped drawings when i modify the mounting structure and outrigger pads.    I have a P.E. on staff so it makes things much more simplified on my end but still wouldn't touch it with a ten foot pole without his blessing.    also how would modifying the outrigger height lower the overall unit height.   The boom mount and turntable stick up above the outrigger and that SHOULD be attached to a torque box sub frame mounted to the trucks chassis.Vantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:You win, I was going to attach the crane with bungee cords, to get the overall height down, we were going to air down the tires.
Reply:airing down the tires would be perfectly legal.Vantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.