Beam Clamp On An Incline Beam Featured

You might run a test, lifting say 800#, 1600#, etc while measuring mid-ceiling deflection, eg with a Bosch laser measure, then extrapolate to "safe" maximum weight. Of course, if the deflection is too small to measure (eg <5mm) then probably no worries. Or if it's several inches, lifting via the ceiling beam would be a no go.* It's the in-between deflection cases that would be harder to decide...

Whether you can reasonably extrapolate also depends on how the support column at the wall is braced. Given the 16' eve height, Euler buckling could occur without warning if the column's not braced both ways when you exceed critical load. Also see***.

• If ceiling beam lift is no go, you might end up using dual rows of stacked cribbing, eg crib a platform beside the trailer up to trailer height, move palleted mill onto platform, and use pallet jack to alternately take out layers of cribbing.**

If the mills was already on a pallet I might be tempted to tilt the trailer and slide the mill off the end with a pallet jack and some ramps. Still wouldn't give me a lift in my shop, but it would get the mill off the trailer. The distance from the column is dictated by shelves, position of the mill (or other stuff in the future) on the trailer, and the parking position options for the trailer. I do have toe jacks so cribbing it onto a pallet "might" be an option. Haven't looked yet if there is clearance for them.

There are perlins connecting the central beam and support column to the front and rear beams and support columns. Of course their are X cables on one side to prevent extreme building shifting in high wind loads, but their tension has never visibly changed. Not even with 70 MPH winds. There is also bracing at a number of locations to prevent beam twist. Pulling from the bottom of the beam straight down, it doesn't seam that beam twist would be an issue.

Each column is bolted to a giant steel reinforced concrete cube.

I tried using some of the online beam calculators to do basic worst case calculations, but they are really a bit beyond me. Well, beyond my attention span anyway. The plug and play calculators don't really do it for me, and I just haven't been able to motivate myself to wade through the lists of formulas on others.

FYI: This is a commercial steel building rated for 100MPH+ wind loads. No snow load was provided, because while I have seen snow here 2 or 3 times, it has always melted as it hit the ground. Even hail disappears very very quickly.

Your shade tree testing approach using a laser tape measure (or a weighted string) is probably the best approach for me to do some basic testing. I just happen to have tens of thousands of yards of string (fishing line) and a 600lb(ish) outboard on a stand almost directly under the beam already. Only a few feet off the intended chain fall location. I have to move the outboard anyway.

I would love to have a nice telescoping heavy gantry crane, but I don't need one often enough to pay the price for one as heavy as I would like. I do have a metal building with a large I-beam across the center. The building is 60' outside dimension, but the unsupported beam (bolted together in the middle at the peak with large flanges) is about 55 feet eyeballing the dimensions. Maybe less. The incline is about 4 degrees. ...

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The gantry hoist I built for my sawmill is an 18' long track supported by tripods at the ends and a moveable A frame at the center, which can be stepped over long logs, up to 20' so far. I designed for 2000 lbs, then had to upgrade for >4000 lb logs from mature oaks that were leaning toward the house, they expand into sunny clearings. One blew down, away from the house, so I lost confidence in the others.

A single wide flange beam would have been better than spliced sections structurally but mine needs to disassemble into parts I can carry and reassemble off-road by myself. The tripods adapt to uneven ground, indoors a wheeled base would be better. I have a towable 1 ton shop crane instead.

Gantry hoists are usually 8' long, mine needed extra length to span the bandsaw head plus the log pile and hauling trailer. My track weighs ~250 lbs without the hoists and can be moved while assembled with temporary wheels bolted under one end and a trailer coupler on the other.

I bought a 2 ton gantry trolley from HF for the upgrade and so far have tested it to 3500 Lbs. On the sawmill two separate chainfalls have proven useful. The second is a 1 ton that operates twice as fast, the 2 ton (not HF) is tediously slow. Amazon had a 2 ton hanging crane scale for under $100.

I assemble the track, trolleys and chainfalls on sawhorses and raise them with a boat trailer winch at each end, the 2 tons are too heavy and awkward for one man on a stepladder. With the upgrade the track hangs from G70 chain joined with G100 hammerlocks. G100 chain has shorter links than G70 and is more difficult to join into slings etc. I bought it at a logging equipment supplier where I could try what fit together and what didn't, my multi leg hardware store G30 chain assemblies could be copied in G70 but not in G100 rating. Apparently chain rated for overhead lifting is made from a less brittle alloy that better tolerates shock loads like falls and electric winch starts. Hammerlocks have ends that fit where shackles won't but they aren't as easily assembled, especially on a ladder.

Perhaps you could suspend a carefully leveled beam track from your existing structure to allow lifting and moving a load off a trailer and onto pipes or machinery mice, then set it on the floor with a J-bar. The important number for online calculators is Ixx, in inches ^4. It's the link between steel beam dimensions in height x weight per foot and load capacity calculation. I use pinned end conditions to simplify calculations and disassembly for storage, and double shear on bolt shanks which is why I modify the thread lengths. The L/360 live load beam deflection limit is to avoid cracking wall plaster, not for strength. I had to exceed L/20 to straighten one piece of the used pallet rack channels for my track, it may have been 50KSI steel.

-jsw

------------------------- Bad example, you can lift the load and move the trailer, and you have tongue jacks.

Besides the gantry I have tripod hoists that lift vertically, equivalent to your stationary suspended hoist. They are cheaper, simpler and lighter and what I use most, though for assembling the parts of a milling machine or similar jobs a moving gantry is better.

No, not a bad example. Sure it doesn't fit my exact situation, but its useful information.

My plan in case I failed to explain it accurately is to lift the load, roll the trailer forward, and lower the load onto a heavy pallet. I'll probably put the pallet under the trailer so that total suspension time of the load will be measured in single digits.

Two things...

1. I have looked at prefab gantry cranes and there are many with adequate vertical clearance... and as you mentioned.. 8 ft width. They do not have an 8 ft span however. Most are 8' to the center of the caster pivots. 94-ish inches between the uprights. This makes it impractical for unloading heavy utility flat bed trailers which are typically 8' wide or in some cases 8'6 inches wide. Wider ones are available of course. A gantry has the advantage of a being able to use a trolley instead of a beam clamp of course.

1. I actually have considered installing a vertical I-Beam to one side of the parking bay. (There are shelves there so it really would not be in the way even though it is an open span building.) Then installing a horizontal beam from it to the near column. Braced of course. This would also allow for use of a trolley instead of a beam clamp. I-beams tend to be lighter than I would like to use or nearly as much as the cost of a complete gantry crane, even for excess inventory, locally.

My plan in case I failed to explain it accurately is to lift the load, roll the trailer forward, and lower the load onto a heavy pallet. I'll probably put the pallet under the trailer so that total suspension time of the load will be measured in single digits.

Two things...

1. I have looked at prefab gantry cranes and there are many with adequate vertical clearance... and as you mentioned.. 8 ft width. They do not have an 8 ft span however. Most are 8' to the center of the caster pivots. 94-ish inches between the uprights. This makes it impractical for unloading heavy utility flat bed trailers which are typically 8' wide or in some cases 8'6 inches wide. Wider ones are available of course. A gantry has the advantage of a being able to use a trolley instead of a beam clamp of course.

1. I actually have considered installing a vertical I-Beam to one side of the parking bay. (There are shelves there so it really would not be in the way even though it is an open span building.) Then installing a horizontal beam from it to the near column. Braced of course. This would also allow for use of a trolley instead of a beam clamp. I-beams tend to be lighter than I would like to use or nearly as much as the cost of a complete gantry crane, even for excess inventory, locally.

-- Bob La Londe CNC Molds N Stuff

---------------------------------------------- My structural steel is almost all scrap, bought for $0.25 a pound at a recycling yard before Bidenflation, based on quick mental engineering of vague plans/wishes. Most of what I bought could be used somehow, if not exactly as intended.

A folding shop crane or engine hoist can be nearly as useful at much lower dollar and storage space cost. A load can be moved without swinging by lowering it onto timbers across the legs. I added a caster tongue jack and trailer coupler to the mast end of mine and tow it with the tractor.

Their disadvantage is that the legs need to straddle or be under the load, so they may not lift from or lower to flat on the ground. A pipe tripod with its feet connected by flat webbing straps (to roll over) can take over for that. Mine are 8' chain link fence corner posts with top acorn caps on the bottom, resting in holes in aluminum plates attached to plywood for pavement use. The taller gantry tripods are 2" x 10' EMT with feet machined from old cast iron fence post acorn caps from a dealer's junk drawers. For level floor indoor use the top leg connection could be a rigid triangle like a camera tripod instead of my fully flexible and sometimes troublesome homebrew.

A tripod of 2" x 10' water pipe is stronger but difficult to set up because the center of gravity is so high. A column buckling calculator shows that the capacity of pipe, EMT or a fence post is quite high as long as the loading is centered, thus the end cap balls and sockets, and machined solid balls for the water pipe shear legs. A truck ran over and bent the third leg so the owner disposed of it to me. I do proof test them with a crane scale on loads too heavy to lift, or drop.

The 6" drill press vise I mentioned was to hold off-pavement steel base plates while cutting the hole. The max for my mill's 4" Wilton vise is 5" with the hard jaws removed, which isn't quite large enough on soft ground. I found a clean, lightly used 6" Columbian DP vise that can take 6-7/8" without its hard jaws. After hole-sawing the center I flare the hole like a trumpet bell to make the socket, and fold down the corners to also dig in. These baseplates haven't needed to be tied together. jsw

Also the pipes alone weigh ~110 Lbs and connecting the 3 top ends on a ladder is difficult and risky with only two hands, it has to be raised with its top ends connected, more weight on top to fight. The neighbor loaned me his 2" pipe tripod but after setting it up once and straining my back I made my own from lighter 2-3/8" OD x 8' fence tubing, which has served very well. I think he set it up while standing on a truck bed or the front of the vehicle whose engine he was swapping. Although EMT may be intentionally soft enough to bend its elastic modulus is the same as any other steel and that's what determines long column buckling resistance.

So far a fence post acorn cap in a beveled hole has been close enough to a ball joint. The point digs in and holds on dirt when a lighter load doesn't require a baseplate. The only breakage was a puncture from a sharp rock in the ground. The EMT ends are cast iron acorn caps too small to fit over the tube, so I turned their OD down to fit snugly inside it. The water pipe shear legs have hemi ball ends turned from a dumbbell.

I don't give load capacities to force you to calculate, measure and be responsible for them yourself, as your construction or usage may vary from mine.

I just don't find much good salvage steel around here, although to be honest I've pretty much quit looking.

I just don't find much good salvage steel around here, although to be honest I've pretty much quit looking.

Bob La Londe CNC Molds N Stuff

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The channels etc for my gantry hoist were salvaged standard shapes, the tripods are new material available from local hardware and big box stores, at least for the 2000# capacity versions. Fence dealers may have stronger posts with thicker walls. The upgrade chain and fittings came from a specialty store beside a tractor dealership. The hoists are from Harbor Freight, Northern Tool and a now-closed discount store similar to HF. I don't usually describe things in detail unless they work well for me and others can buy or duplicate them.

I looked at Harbor Freight and they sell an "okay" 1 ton gantry crane. With a maximum lift height of 148 inches and a product width of 128 inches it wouldn't be too bad for a shop crane except... well... its only rated for 1 ton. They may have sold other options in the past, but its the only one available today. Much like their machine tools that have been paired down to just a few of their smallest selections compared to the past.

I do actually have a gantry crane. Sorta. Its an twin a-frame with a cross bar made out of what looks like old heavy well casing all welded up. Its high enough to lift an engine out of the engine bay of a pickup truck, and just barely wide enough to fit around the fenders of one. Not much use for this application though. A fellow I know (not a good human being) loaned it to my dad maybe 50 years ago. My dad told him he could have it back when the guy paid him the money he owed him. I don't think my dad ever got his money back because we still have it, and amazingly that coyote never stole it out from behind the grocery store where we kept it in an open yard most of those years. Of course all I ever used it for was pulling and installing engines. Mostly (now that I think about exclusively) V8s. 318, 360, 351, etc etc... No wheels. Just steel pads under the four feet. I kinda liked it better than a cherry picker for pulling an engine. I guess next time I run out to my folks place I'll have to see if I can drag it up onto a trailer. (Its freaking heavy.) I might need a gantry crane just to stand this one back up.

You know... there is another cherry picker out there too... and another engine stand...

"Bob La Londe" wrote in message news:v9m19s$14brv$ snipped-for-privacy@dont-email.me...

I do actually have a gantry crane. Sorta. Its an twin a-frame with a cross bar made out of what looks like old heavy well casing all welded up. Its high enough to lift an engine out of the engine bay of a pickup truck, and just barely wide enough to fit around the fenders of one. Not much use for this application though. A fellow I know (not a good human being) loaned it to my dad maybe 50 years ago. My dad told him he could have it back when the guy paid him the money he owed him. I don't think my dad ever got his money back because we still have it, and amazingly that coyote never stole it out from behind the grocery store where we kept it in an open yard most of those years. Of course all I ever used it for was pulling and installing engines. Mostly (now that I think about exclusively) V8s. 318, 360, 351, etc etc... No wheels. Just steel pads under the four feet. I kinda liked it better than a cherry picker for pulling an engine. I guess next time I run out to my folks place I'll have to see if I can drag it up onto a trailer. (Its freaking heavy.) I might need a gantry crane just to stand this one back up.

You know... there is another cherry picker out there too... and another engine stand... Bob La Londe CNC Molds N Stuff

------------------------------- The Net has several plans to build your own, which might help with the engineering of swapping a long and strong enough beam for the well casing and choosing suitable casters. Trailer tongue jacks could move it (unloaded) and set it down for use.

My gantry hoist is meant to be set up by hand in the woods to lift and move a log or boulder, and disassemble for compact storage. Though it works very well on the sawmill it has too many compromises to be a good pattern for general use indoors. jsw

------------ A key difference between mine and standard gantry designs is the free standing tripod legs, which allow the beam, trolley and chainfall to be raised without other help, but to be light enough to set up by hand they aren't stiff enough to withstand the cantilever loading of the standard design. The beam hangs from chain and loads the legs in pure axial compression.

At least I think it does, I can't mathematically or experimentally prove how well the compound angular geometry distributes loads equally among all 6 leg cross bolt ends. Three are pretty certain, the others not so much. They are free to try.

There may be other ways to design a self-assembling gantry crane, perhaps temporary or fold-out extra legs that make the end posts free standing until the beam is bolted in place. Mine is set up such that I can lift the beam and move the loaded trolley from outside the leg and beam areas.

The method I use to attach a temporary outdoor beam extension to the fixed gantry in a storage shed is to put a folding W frame ladder at the center of the beam position, place boards across the rungs nearest the beam height, slide the two 3" channels that form the trolley track onto the boards, which support them while I loosely attach the shed end, and then set up and connect the braced post at the outer end. Removing the boards lets the ladder be lifted off the beam. Although channels aren't ideal for the trolley track each is light enough to lift above head height. When I bought the 3" channels I didn't know that a few 4" ones with higher capacity were behind the bushes on a separate pile.

There may be other ways to design a self-assembling gantry crane, perhaps temporary or fold-out extra legs that make the end posts free standing until the beam is bolted in place. Mine is set up such that I can lift the beam and move the loaded trolley from outside the leg and beam areas.

--------------------------------- Here are some ideas that may not be too difficult to DIY. They appear to use common structural shapes pinned or bolted together at flat plate fittings small enough to make with hobby sized machine tools.

A track made from two channels can be attached to uprights and diagonals by sandwiching them between the channel webs. For instance a two channel track could be attached atop wood posts with angle iron trimmed to fit between them and bolted to the posts. The diagonal brace could also be two angles with their ends cut down to fit between the channels and bent flat against the post, though mine are 3/8" bar welded into the slotted ends of pipe. The outer post for my temporary track extension is a braced landscape timber with the track hung on a 1-ton-rated turnbuckle to level it. I think a gantry track made from channel iron makes sense if you need manageable weight, compact storage and versatility for one-time setups more than high capacity for frequent use. jsw

I have to admit I don't always read your posts from end to end when I first see them. I skim them, and then come back later and read them more thoroughly if there was something that caught my attention. My bad really. Often I review them on Narkive from my phone later when I am winding down for the day. I just saw the comment about c-channel. I actually have a few pieces I bought as salvage from a buddy to repair an over stressed hydraulic press. I've since got another hydraulic press the same size from my dad's shop so I no longer need to fix my old one. I'll have to walk out back and see how much c-channel I have. Heck, I have a couple pieces of 1x6 4140 12 feet long too. I bought extra for a press die job a few years ago. On edge that stuff could probably 8-10 or more tons if it could be kept from twisting. Welding it might not be a good idea though. I have no practical way to anneal or heat treat anything that big, and it came in HT hardness for the dies. I'd have to make a bolt up assembly with it.

I fall into a bad habit of not wanting to use my "good stock" unless I am getting paid a lot for it. The thing is all that "good stock" was paid for a long time ago.

I still have 9 out of 10 sheets of 1/4 inch plate I bought a while back because the price was right too. I saw a guy make a welded 30 ton press out of that same type of stock a while back.

I guess I should just stop bleating and make something.

That's fine, I click Send when I'm bored with proofreading and editing them myself. I try for completeness so they might serve as an unfragmented reference if someone has a relevant problem to solve. Mostly I post for practice in technical writing which I flunked several times, and they are tests for senility when I read them back later.

I found another way to set up a gantry without a separate hoist, by making the supporting posts pivot on horizontal bolts at the ends of the beam. If the beam is raised a short distance as on sawhorses the chainfall, pinned to the track, can pull against the base of a support to fold it further inward. The reference mentioned ratchet strap pullers to help as well. I tested a 2" ratchet cargo strap for vehicle recovery and it reached 1000 Lbs tension while pulling my truck through a snowbank. jsw

Many ideas here, if I got this right: