[OT] - Lift Trucks

We have a CAT 125D Fork truck. It's rated for 12,500 lbs. We also sell a machine that supposedly weighs 12,100 lbs.
I believe the machine is a bit heavier than advertised. When we try to
pick it up the back wheels come off the ground. If I had to guess I would say it's more like 14,000 lbs. With the base casting weight being 12,100lbs.
As a result I have to hire riggers every time I move one in or out or just want to plain move one around. Today we needed to move one about four feet, so we picked it up with the truck and slid 4x6's under it then dragged it back. It was a little dicey as the rear wheels were well off the ground during the lift.
Anyways, the riggers more often than not use a 12,000 lb. truck with weights on the back. They mave these machines around with no trouble at all.
So I'm wondering, how much weight do I need to put on the back? Do I need to upgrade the forks? How much over capacity can you go with some counterweights?
I'd hate to get one of these things five feet in the air and have a fork snap off, or a hydraulic cylinder fail.
I'm going to call a CAT dealer and try to get some answers. But seeing it's after five, I thought maybe someone out there knows a little something about this.
We are selling quite a few of this model machine lately and I figure any money I spend on the truck I'll recoup in saved rigging costs.
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Dan

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Dan, If your fork truck is lifting the rear wheel off the ground then that machine is probably MUCH heavier than you think. Unless of course the machines Center of Gravity is out farther than that listed on the nameplate for the forktruck capacity. Fork trucks at rated capacity are usually not at all tippy, because the rating has to take into account that a forktruck moves, and a sudden stop radically changes the tipping moment.
I once owned an old Navy forklift (had lifting rings so it could be handled by a crane) that was rated 4,000 lbs. Our truck mechanic comes in one day and says that it won't lift the back end of our tandem axle crane carrier, it starts to lift it's rear wheels. Well duh, the back end of that truck weighs at least 25,000 lbs!
What you said about riggers is very true. Everyone I have ever seen has some huge old piece of iron they chain to their tiny little forktruck, so they can fit it in some tight place to move some huge load. They seem to work on the principle that if it will raise it off the ground without blowing hoses or seals then it's okay.
For me the question is simple. What is the load worth? Can everyone be safely out of the way when you do the lift?
On the question of what is the load worth I had an interesting one. The RCA space Center wanted to rent our little sign crane to move what they said was an empty shipping container, from one building to another, and back again. I was suspicious and pressed for what was in the container. Just a bird they said. As in satellite. $21,000,000 worth! Got them to send me a legal document that said if I dropped it, it was just tough shit. My lawyer looked at it and said go for it. The last one I lifted, out of the box onto a fixture and back again was worth $66,000,000!
Good luck with it.
Gary H. Lucas
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"Gary H. Lucas" wrote:

I'd suspect it's really a CG issue based on the comment that the riggers use a 12,000# cap truck with counterweights. I expect that a machine that weighs 12,000#+ does not have a CG the 24" or so out the forks that most forklifts seem to be spec'd for.
Certainly it shouldn't be all that difficult to pick the machine up until the rear wheels of the forklift start to lift and then start adding weight to the back of the forklift and see how much it takes to get the wheels back on the ground.

Riggers also know not to lift the load any higher than they absolutely have to. I have no idea what planet the OP is on talking about lifting a 12,000#+ load 4 or 5 feet off the ground. If you're just moving the machine from one part of the plant to another you shouldn't have to lift it more than a few inches off the ground.
Pete C.
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Heh. I'm from the planet where I have to lift it onto and off of an air ride trailer in the parking lot.
When the riggers brought the last one in they lifted it eight feet off the floor, up over another machine, tuurned 180 and set it down in a narrow aisle.
I wouldn't do that even if I could. I'd get it close and skate it in.
I've been thinking about air pallets too. That solves the problem of just moving them around after the riggers drop them off. But air pallets are a bit treacherous too. Plus you need at least three people to use them safely. In our situation we often have to move machines by ourselves.
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Dan

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D Murphy wrote:

You must have a really good parking lot if you can put that kind of forklift wheel load on it without sinking in or crushing it. Even for loading trucks like that I wouldn't exceed the few inches off the ground until I was right next to the truck.
At a place I used to work I had to put down plywood if I wanted to take the 10,000# cap, ~16,000# curb weight forklift into the parking lot any time other than winter or it would sink in even without a cargo load.

If that is necessary it sounds like you should be looking for a new building.

Certainly something to be avoided if there is any other way to do it.

By yourself a forklift is probably safest since it keeps you fairly protected in the forklift seat.
Pete C.
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Thanks for the input. Two of hung off the back, so that added about 400lbs plus leverage. We got close to the ground but not quite there.
We were as close to center as we could get. There was less than three inches between the mast and the front of the machine. But if I had to guess, I'd say we were six inches off to the bad side.
The other issue with adding weight is I'll need another truck to get them on the back of this truck. Maybe I can rent a hoist.
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Dan

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D Murphy wrote:

Mount two 55 gal drums on the back and just fill with water.
Pete C.
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Hey D,
Next time, have a couple of heavy guys sit on the rear and see if it helps. Gives you a rough idea.
You can fasten open-top containers on the back, and then fill them.
Water weighs a bit over 60 pounds per cubic foot. Cheap, but must be in a "good" container. Sand weighs about 100 per cubic foot, and doesn't leak as easy.
If you want to go one better, make sure the containers have a decent size capped hole in the bottom, and then just "dump" after use so you can reduce the weight on the steering wheels when you don't need the heavy lift. Water is cheapest for sure then. And you can pump or siphon water out instead of a "dump".
Wet sand (that's a cubic foot of sand in a container and water added until it's overfilling) weighs about 120, but it doesn't "dump" with simple caps. You have to get fancy to get it out.
Rough calc, a 12" pipe (say a piece of piling material) about 3 feet long would hold 2.35 cubic feet of ???. If you had three of these you could hook and un-hook at the back of the lift truck, then filled with water from the hose, you could have over 400 pounds plus the weight of the pipe. That's a fair "lever", and cheap to try. An old 200 US gallon fuel oil or diesel fuel tank would get you over 25 Cubic feet, so with water that's over 1600 pounds.
Some traveling cranes use sand or gravel in LARGE tank-style weight boxes. Saves owning counterweights and having an auxiliary truck to transport them.
Take care.
Brian Lawson, Bothwell, Ontario.

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[..]
Brian,
Thanks for the sand idea. I like it.
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Dan

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Dan, Also consider how FAR off the back of the tow motor to put the weight. The further away, the less weight you need to achieve the same effect.
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Anthony

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A place I used to work made a big box, then filled it with concrete. You didn't have to worry about it spilling.
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Dave Lyon wrote:

55 gallon drums filled with water and hung off the back from a bracket work well too. You also get the advantage of having a bit of a lever arm and they can easily be emptied and removed.
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John R. Carroll
Machining Solution Software, Inc.
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Dan, Solid concrete blocks are a MUCH better idea than sand. Density is about 125lbs/cu/ft. Cost about $2.00 each for 60 lbs or so. You need only a shelf or box to stack them in and you can do it by hand in ten minutes, no mess. They have lots of other uses too. Like as a platform when the forktruck is just a smidge too short!
We bought a forktruck off ebay last year. 8,000lb capacity derated to 7,000 because it's got 6 foot forks that hydraulically spread to 7 feet wide, and side shift about 3 feet. Caterpillar brand, about 1000 hrs on it, $2,000 DELIVERED! What a freakin steal, I couldn't believe it when I saw it. The company sold off 23 forktrucks on ebay at one time. This one must have been a sleeper.
Gary H. Lucas
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I thought we stole ours. But you win. IIRC, we paid eight grand for the truck, a granite surface plate, as new 20" drill press, newish Dell desktop with flat screen monitor, pedastal grinder, mitre saw, electonic scale, mig welder, a crate of lathe tooling, torque wrench, circular saw, portable band saw, and some other odds and ends.
That was 2002. It's good to have a little money when the economy is bad.
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Dan

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Keep your eye on Ebay for a 15,000lb truck.
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Anthony

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I would. But we honestly don't have that kind of room. With the park we're in I can't keep it parked outside either.
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Dan

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Sounds like you need to move :P
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Anthony

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Yup. Not an option for 30 months or so.
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Dan

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Five feet in the air? I generally don't take them more than 1 inch off of the ground.
I've seen people climbing on the back of a hilo when the load was a bit much. The forks will deform before they snap. If you are going to push the limits, check all the hydraulic hoses.
Wes S
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You should check into what size hilo's you can rent. Should be cheaper than riggers since you bear the liablility issues.
Wes S
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