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Homemade bridge crane

smootz

Stainless
Joined
Dec 5, 2005
Location
Southern Ohio
I admit it ----I'm spoiled!

After years of working in and later leasing shop buildings with nice overhead cranes I am really getting tired of fighting with the variety of jib cranes in my home shop. One hernia surgery is enough for anyone so I am always trying to find a safer way to lift and re-position stuff.

I would like to build a small "work station" grade bridge crane to cover the front half of the shop. It would span 30' and travel 40' with a 12' ceiling limiting my height. It would be more for positioning and turning fabricated assemblies (less than 3 tons) so we are not talking everyday use. I just want a simple, manual, preferably low cost way to move stuff anywhere in the area that I want it. I have done the gantry crane thing and own a couple of forklifts. They are always in the way when using them for fixturing/positioning.

Have any of you built a similar contraption for your shop? If so I would love to see some photos and/or hear some ideas before I start buiding my own.

SCOTT (fabricator - wanabee machinist)
 

j king

Stainless
Joined
Oct 27, 2003
Location
ohio
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I showed this last year.Works great for me.It spans only 12' so nothing too bad.You should find a used one and cut it to fit since you want such a large one..that isnt a small crane.They go cheap at auctions.
 
G

Guest

Guest
One hernia surgery is enough for anyone so I am always trying to find a safer way to lift and re-position stuff.
Since I have had two back surgeries I should
lurk here and take notes, pain killers and JD
will only take you so far.
 

matt_isserstedt

Diamond
Joined
Dec 15, 2003
Location
suburbs of Ann Arbor, MI, USA
I have done a lot of "thinking" on this subject, never actually built one tho.

The Whiting Crane Handbook is about the best text you can get, there's some info out there on the internet with a lot of searching. Many mega-bridge cranes have been built.

Random list of thoughts

- You have to decide on top-running or underhung (from trolleys), you have to decide how many motions will be powered. Underhung is probably simpler for lighter loads like you are talking but requires scrounging or building trolleys.

- You need enough width between wheels on the end trucks so that the bridge beam doesn't rack itself into a bind. You also need a very consistent track width, measured across the bridge beam. For underhung, there is one advantage in that ideally one runway rail would float from gimbal rods. For top-running, the wheels require a tapered surface kinda like a train to help self-align. My reading suggests 1/6 to 1/7 of the span should be the length of the end trucks. Also consider that when the end trucks reach the end of the runways, there's a "dead space" where the crane can't reach, like up against a wall.

- For a long span like that I think I'd recommend either a double bridge beam (double girder) or else a cap-channel on a single bridge beam, if it's something like an "I" beam.

- If making your own trolley wheels, many texts suggest nodular/ductile iron as the preferred material for good wear characteristics. The larger the diameter, the easier the hoist will roll.

- All horizontal members must be well-leveled, both the runway and the bridge, otherwise the load will takeoff downhill with surprising momentum. As such, adjustments must be possible and built into the design with pinned threaded devices or shimming.

- At all times consider safety...if possible, backup the trolley hangers with a safety cable. Make sure you put end-stops on both the runways and the bridge beam. These should be angle irons bolted to the web if an "I" section.

The bridge crane is a tradeoff...lots of work, thinking, and pretty good sum of steel tied up in the system. However, once built, as you said, there is nothing on par as far as lifting, spotting and positioning. Machines *can* fly ;)
 

smootz

Stainless
Joined
Dec 5, 2005
Location
Southern Ohio
Great stuff guys! I like the double beam idea with a top runner. That would really increase the headroom with my short (12') ceiling.

What is a "gimbal rod"?

SCOTT (fabricator - wanabee machinist)
 

smootz

Stainless
Joined
Dec 5, 2005
Location
Southern Ohio
Great stuff guys! I like the double beam idea with a top runner. That would really increase the headroom with my short (12') ceiling.

What is a "gimbal rod"?

SCOTT (fabricator - wanabee machinist)
 

matt_isserstedt

Diamond
Joined
Dec 15, 2003
Location
suburbs of Ann Arbor, MI, USA
Gimbal is Acco's special name for a "ball-joint-threaded rod" for Louden rail systems. Louden rail is a "patent track" or non-tapered-flange I-beam, that's fabricated (stitch welded) from a hot-rolled steel upper and a tool (alloy) steel lower. The patent track requires flat rollers and not tapered rollers as would be used on a classic hot-rolled "S" or "W" shape, but the flat lower flange allows long life and easy rolling, no special tapers.

Back to gimbal rod, essentially it's a made-to-order stud, (threaded ~6 inches on each end) for lack of a better word, I've seen them 15 feet long, I've seen them 2 feet long. I think the threads are rolled and not cut for strength.

The Gimbal rod has a part that would be the result of a single slice thru a full sphere, forming a thick partial sphere "chip". This is tapped down the centerline for the same thread as the rod, and backed with a castle nut.

The partial sphere chip sits in a plate with a slightly oversized hole thru it, with the hemispherical chip bearing in these plates top and bottom.

The idea is that the double "sphere" joint allows the I-beam rail below to swing sideways but still remain level to the earth, that keeps the trolley level and centered too.

Of course the effect is more and more pronounced the shorter the rod.

Often-times the rod is sent thru back-to-back structural channels, spaced at intervals with flat-stock to make sort of an "open-web-I-beam"

Geeze, after all that typing I found this :D

http://www.accolifting.com/loudenshowcase.html

Maybe that clears it up better? My reading suggests that the track width from one runway to the other (across the long span of the bridge beam) should be +/- 1/16" over the entire span :eek: and I'd SWAG it should be +/- 1/2" for one rail hung from the gimbal rods...however care should be used in the underhung/gimbal because that's supporting all the weight (if the hoist is travelled to the extreme ends of the bridge), as opposed to a series of "knees" or other column supports for a top-running runway rail.
 

matt_isserstedt

Diamond
Joined
Dec 15, 2003
Location
suburbs of Ann Arbor, MI, USA
Adding, on a different subject, for Jim's design in heavy service I'd recommend a strengthening "hoop" be added at midspan, possibly at 1/3 or 1/4 spans, essentially a plate steel inverted "U" shape that keeps the tracks/beams from spreading, while still allowing the hoist to pass. (Think permanent c-clamp)

An important part of making the hoist's carriage is selecting the bearings for large static loads, not just the rated load but also include extra for some kind of shock load the hoist is eventually bound to see.
 

wippin' boy

Diamond
Joined
Sep 14, 2005
Location
il.
with only 12' of ceiling
a rig similar to jkings is were you will probly end up.
but a 30'bridge is a pretty fair span
my old build had similar
only a 5 ton outfit
the brideg was 2 pieces about 12 or 15" by 1/2" thick ibeam for a similar span
thats some big steel
better get the math boys in on something like that

good luck
 

macona

Diamond
Joined
Jun 20, 2006
Location
Beaverton, OR
You coule biuldsomehting like this. Overhung sytem using railroad track as rails and 3 huge copper sliding bus bars to carry power.

This is at John Day dam when they were pulling out the rotor from one of the generators for maint. Looked like a flying saucer traveling through the building.

Even in their machine shop (Maybe 1800 sq ft they used a similar method and I think they still used standard train track for their rails

DCP01435.jpg


DCP01439.jpg
 

matt_isserstedt

Diamond
Joined
Dec 15, 2003
Location
suburbs of Ann Arbor, MI, USA
Macona, yes the "train track" is also referred to as ASCE rail and comes in a lbs per foot rating.

This nice website has all the dimensions conveniently posted on there.

http://www.bhamrail.com/railproduct.asp#

I think Whiting has a section devoted to how to size the ASCE rail.

This is where the slightly tapered wheel face comes into play, to naturally correct a wheel that wants to run on a line that would attempt to rack the bridge into a bind.

There a couple styles of clamps for the ASCE rail, to allow tweaking the track level and to a consistent width.

For top-running rails, a safety device also must be fabricated so that in case the bridge or hoist came off the rails by some event, it wouldn't simply fall to the floor. An internal profile which closely mimics the ASCE shape, with a little clearance, but could not be withdrawn vertically from the top flat running surface/flange is what I see most often.
 

CBlair

Diamond
Joined
Sep 23, 2002
Location
Lawrenceville GA USA
There is a member of this forum who has just had a book printed where he discusses and has photos of his overhead crane solutions. I dont remember how many he has but they are very well thought out. His name is Randolph Bulgin and his book is titled Randolph's Shop. You should be able to find a link to it by searching. There are just too many ideas to discribe here but it is well worth the read.

http://www.randolphsmachineshop.com/

Charles
 

Randolph

Aluminum
Joined
Feb 15, 2004
Location
Franklin NC USA
Thanks, Charles, for mentioning my project. But I have to point out that my cranes, and I have 5 of them in and around my small shop, are shown in the book as examples only. Nothing beats a good system for lifting things you either are not capable of lifting by yourself, or just don't want to lift by yourself, but be sure that it satisfies all of the criteria for good and safe design. Of all of the things I discuss in my book this is the one area where I do not want to be perceived as giving advice.
 

jkilroy

Diamond
Joined
Jul 23, 2004
Location
Vicksburg, MS
I had been looking at doing similar and decided to buy a gantry instead. With steel costs the way they are covering a 13x60 area was going to be EXPENSIVE and take up a lot of very valuable floor space. I got the gantry for roughly a buck a pound from Fastenal.
 

dsergison

Diamond
Joined
Oct 23, 2003
Location
East Peoria, IL, USA
no reason the side rails cant be WOOD attached right to the wall. like a strip of 4x4's lag screwed into each stud. wheels rolling on top.

perhaps a nice truss, something like sections of a ham radio antenna. or a pair, can serve as the bridge. with the crane suspended between them.

I can see it now.
 

Randolph

Aluminum
Joined
Feb 15, 2004
Location
Franklin NC USA
I proof tested mine in a very rudimentary and unscientific way. I centered the trolley on the beam and centered the beam on the rails and lifted a 36" X 48" X 2" thick welding table. The table, including its welded on legs weighed pretty close to 1000 pounds. I have never lifted more than 300 pounds in daily use and probably won't have to exceed that.
 








 
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