Gantry Crane Top Beam Lift For Easy Height Adjustment

The beauty of a gantry crane is the beam overhead, with clear access for lifting things.  Telescoping legs make them even more useful by setting the gantry crane lift point at an appropriate height for the job – in your garage, or outside, or wherever.  One of the challenges is physically moving the top beam up and down.

Yes, telescoping legs allow various positions of the top beam height, but positioning the beam is not easy.  The top beam (and trolley and chain fall) are heavy, and we have to lift it into position before we pin the telescoping legs.

How can we lift and lower the gantry crane top beam to meet the needs of the moment?

We have seen some cool ideas.  Some are simple, and some are more complicated.  See the Customer Stories page.  I have seen sketchy stuff too, violating common sense like in this article about Crane Safety.

In this article we explain several ways to lift and lower the gantry crane top beam.  We will discuss various options, including the simple brute force methods, some things our customers have done, then a couple of more controlled, mechanically assisted solutions.

Problems With Lifting The Top Beam

Telescoping legs are awesome on a gantry crane.  They offer the convenience of raising and lowering the top beam to fit the situation.

For me, the crane is usually in the garage which has a limited ceiling height.  In the back of the shop I can put it up higher.  In the front of the shop I have to work under the garage door opener.  To move it outside, I must put the beam all the way down (to fit under the door), but once I am out, I can put it all the way up.  That is the beauty of telescoping legs.

Ah, but the beam can be heavy, and awkward because it is long.  Often it has things attached, like an I-Beam trolley and chain fall, so lifting or lowering the top beam to adjust the height is a chore.

It really takes 2 people to adjust beam height safely.  Unfortunately, I often don’t have a second person, which makes things difficult.  Usually that means the crane height must stay where it is.  So, how do we adjust the top beam height?

The Brute Force Gantry Crane Lift

Our Gantry Cranes plans with full engineering do not come with a means of elevating the top beam.  The plans focus on minimal components for making the crane mobile and modular.  The mobile gantry cranes are intentionally on the lighter side of industrial – not huge capacity, but certainly not lightweight.  This, so it is mobile.  (Easy to assemble and disassemble for transport.)

So . . . How do you raise the top beam on your Gantry Crane?

Earlier, our way was brute force, with 2 people.  This image shows how we did it.  The 2×4 (wood board) in the photo is the right length so one person can extend the leg, while another person inserts the pin.  Lift one side, then the other.  It actually works pretty smooth and quick, though going all the way up usually means taking it in steps.

This gantry crane lift process takes 2 people – at least one who is strong enough to heft the crane.  And, going all the way up, requires a couple different board lengths.

Going down is the opposite.  Not a big deal.

Oh, but make sure the board is firmly on the protruding bolt ends or the board may slip.

But, what if you don’t have 2 people?  Or what if you need to lift the gantry crane in a more controlled way?  After all, the technique with the 2×4 relies on brute force.

These are the questions some customers are asking.  Fortunately, we now have a solution – (actually two).  One is the add-on that some of you have requested.  The other, if you are building a new gantry crane, is a winch driven lift as a plan conversion to accomplish the task.

Other Crane Beam Lifting Possibilities

This field has been plowed a lot of different ways.  Here are some things our customers have done.

1. Lifting the legs hand over hand.  It takes a few strong hands, but this technique works.  We do it here, also, when we have a few strong people to help.
2. Set the crane height once and leave it.  For a few customers with gantry cranes, that seems to be a theme.
3. Hydraulic cylinders.  Adding some long reach hydraulic cylinders or jacks to the legs is a nice way to lift.  It is not quick going up, but it is certainly smooth and controlled.

I like the example in the image.  The cylinders lift the gantry crane smooth and easy with air over hydraulics.  This customer uses air from his compressor, instead of hand pumping the jacks.  (I will point out that this method has some big stress issues if you try lifting the beam while a load is hanging from the crane.)

Because of ram length, there are limits to the gantry crane lift.  To go up or down more, the clamp on the upper leg must move.  The idea is good, but it does require extra steps for large top beam movement.

Mechanical Lifting Ideas

4. Another customer requested something similar, but with a long piece of threaded rod (aka All-Thread).  Drive it with a drill or air wrench, because that is a lot of turning to go all the way up.  The image below in the “Threaded Gantry Crane Lift” section shows the concept.

I like this too.  It is pretty cheap, fairly easy, and not too bulky or heavy.  Just make sure the rod is stout or it will buckle.  See the information below because this can extend a long way.  This too, is better lifting in steps – a little on one side, then a little on the other side as the top beam goes up or down.

Using grease will make it messy, but if you do it dry, the internal threads will wear.  Graphite is an option, but that will make things black if you touch it.  Pick your poison, but we recommend lubrication of some sort.  For me, I put old bicycle inner tubes over the threads to protect the grease.

So, that is where we have been mentally.  And, (I have to say) also into many other hair-brained ideas.  We will not get into those.

When the dust settles, we have 2 good ideas that work well with our Gantry Crane Plans.  The first is an add-on.  The second is a winch driven solution, which is a conversion (or change) to our crane plans.

Threaded Gantry Crane Lift

To understand the system, we did the engineering, then made some good plans for this gantry crane lift design.  (The plans show a better design, but the simple design in the image below is where we started.)  From an engineering perspective, here is what we found.

• The threaded rod is a column, so the size (diameter) you need depends on how far you need to lift.
• First, calculations are based on lifting 150 lbs (1/2 of the top beam weight + trolley + chain-fall), a full 3.5 feet lift, using a threaded rod (Class B7), configured like in the image.  Note this needs a pocket in the upper leg receiver (dark pink in the image) to guide the top end.
• Calculations show that a 7/8″ or greater diameter is necessary to safely lift to a full 3.5 foot extension.  When lifting shorter than 2.5 ft, a 3/4″ diameter threaded rod will work fine.
• For those of you that like nitty-gritty engineering detail, a 3/4″-10 (coarse thread) is on the verge (may fail) at 3.5 ft gantry crane lift.  A 3/4″-16 fine thread is marginal – unsafe.  Calculations say a 7/8″ diameter threaded rod (coarse or fine thread) is best for this lift.  Note, Coarse thread will require fewer turns for the same lifting.  (And 7/8″-9 (coarse thread) is more available.)

If you try this, go up a little on one side, then some on the other side, back and forth so the top beam is not too far from horizontal.  Better yet, a person on each side, so the top beam will rise somewhat evenly.

CAUTION:  The Pins (red in the image) are required for crane use.  Use the threaded rod to lift the gantry crane top beam, then PIN IT before using the crane.

A Winch Driven Gantry Crane Top Beam Lift

The new approach makes use of a hand winch for a controlled mechanical advantage.  One winch attaches to each lower leg with the cable going into the leg.  Crank the winch and the leg extends, which lifts the gantry crane top beam.  Stop at a place where the hitch pin holes align, then insert the pin.  Do that for both sides, and that is it.

This is especially useful for small shops where lifting the beam by hand is difficult or unsafe.

The winches are for height adjusting only.  Do not use the crane without the hitch pins securely in place.  The hitch pins hold the weight that the crane lifts, not the hand winch.  Once the pin is in, release the winch pressure, and the crane capacity is the same as defined in the crane plans.

This method is nice because it does not require “steps” as it lifts the beam.  In other words, it does not require going up a bit, then stopping to move clamps, then going up some more.  The winch is always there, so the release is just the opposite to lower the beam.

Yes, it would be nice to have just one winch to lift both sides, however, the extra parts make it impractical.

This approach is not a retro-fit for an existing gantry crane, unless the lower leg is simply replaced.  It is, however, a great way to build a new gantry crane with the lift.  That is why we call it a “plan conversion”.

Some Caveats

With every idea, there are trade-offs.  Added function usually requires more parts, for instance.  Here are some more things to consider with this winch lift approach.

Advantages

The winch provides controlled mechanical advantage, which allows smooth lifting without relying on human strength or step-wise repositioning.  Here are the advantages.

1. Lift the beam with just one person.  Do a little on one side, then move to the other, and back and forth.
2. Relatively low forces required to change the beam height.  Just crank.
3. While winching, the operator can stand in a position facing the crane to see what is happening during the lift.
4. The winches are easily strong enough to lift the gantry crane top beam with a trolley or chain fall or other lifting mechanisms.  (Hold the trolley, however, or it will roll from side to side.)
5. With 2 people cranking simultaneously, the beam can go all the way up (or down) and stay horizontal.
6. Mechanical hand winches are simple devices that do not require other facilities — like air or electricity.  You can put power motors on if you wish, but the basic mechanical design is nicely simple.
7. Normal function of the crane is the same.  Load capacity does not change.  Beam height, max and min, does not change.  It is still mobile for rolling around the shop, too.
8. The concept is simple, and universal for the Mechanical Elements gantry cranes.  New plans will convert any of the current Gantry Cranes in our Shop Tools Department.
9. Most of the added parts are Off-The-Shelf.  True, some parts are cut from standard steel stock, but most of the components are available in a few days from McMaster.com

Disadvantages

1. Adding this gantry crane lift function is pretty easy when building the crane.  It does not retrofit, however.  If you want it for an existing crane, you will need to build new lower legs.
2. Because there are more parts, the project will cost more.
3. The added function adds weight, which makes the crane less mobile.  Also, with the upper leg connecting to the lower leg (via the cable), it is harder to take apart for transport.  The top beam can still come off, but the leg sections should stay together.

Considerations (Not really disadvantages, but things to know.)

1. Remove any load before lifting.  (This is not different than the standard crane.)  The gantry crane top beam cannot lift when the crane is holding a load.
2. A trolley will roll from side to side as the top gantry beam lifts, so you must hold it or tether it for lifting.  (Again, not different than the standard crane.)
3. With one person, the beam will not stay horizontal when it is moving up.  Lift one side a little, then lift the other.  Of course, while going back and forth, you do not need the hitch pins, as the winch will hold it.  Pins must be in place before lifting a load with the crane.
4. The winch ratchet increments may not hold the upper legs perfectly at the point to insert the hitch pins.  It may require holding the winch between ratchet steps to insert the gantry crane leg pins.

The above lists are not exhaustive, but that should give a good picture.

Gantry Crane Beam Lift Q&A

Q:  How do you lift a gantry crane beam safely?
A:  Use a controlled method such as a winch or threaded lift to raise the beam, then re-insert the leg hitch pins before using the crane.

Q:  Can one person raise a gantry crane top beam?
A:  Yes, when the telescoping crane legs are fitted with mechanical assistance, such as a winch system.  Without it, raising the top beam typically requires two people.

Q:  What is the best way to adjust gantry crane height?
A:  It depends on your needs.  A winch-driven system provides the most control and ease of use, especially for frequent adjustments.  A screw drive system is a little simpler, but not quite as convenient.

Q:  What is the difference between a “Conversion” and an “Add-on”?
A:  A conversion is a change from the original plans.  For our gantry cranes, the conversion plans show you how to make a different lower leg to work with the winch.  You make the “conversion”.  The Add-on, like the threaded rod beam lifter above, can be added to an existing gantry crane.  It does not require changes to the existing crane.

How To Make The Conversion

Our new Gantry Crane Lift Conversion Plans are not an add-on, rather, a conversion, because it changes things from the original plans.  The Conversion Plans are separate to avoid confusion, because not everyone will want the gantry crane lift by winch.  Also, if you already have a crane, then you will want only the conversion plans.

Converting is pretty simple.  For a new crane build, just choose your crane, then buy both the Gantry Crane Plans and the Conversion Lift Plans.  Those 2 sets of plans will explain everything you need to build an awesome gantry crane with a pretty cool top beam lifting mechanism.

If you already have a gantry crane build from our plans, you will need to build new lower legs to get the new lift function.  The upper leg can easily modify, but the lower is significantly different.  Also, the wheel assemblies can simply transfer to the new lower leg.

Good Luck With Your Gantry Crane, Beam Lift Project !!