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plunger
10-30-2013, 01:46 AM
I need to make a lifting or holding structure to enable me to take my rebuilt engine off my pick up . I dont want to buy a cherry picker as this is for a once off project and a cherry picker is bulky and I have no space for it. This is also Africa so we dont have any harbor freight stores. My pick up is 2..1 m wide . It needs to be 2.5 m wide to clear the vehicle and it should be 2meters high minimum. Does anyone have a simple design for a gantry that can hold a metric ton? I am thinking on the lines of making it out of pipe and after the project is finished I can cut it up and put the metal in my scrap metal projects bin.
Thanks

boslab
10-30-2013, 02:03 AM
Id use i beam for the rail, deeper the better and tube for the legs, at a pinch ordinary scaffolding tube will happily support a ton with standard fittings, several tons if uniformly distributed load, like packs of bricks on each lift, they are about 700 kg, holds them up ok, think about the ties of the uprights too, most failures happen there allowing the lehs to spread, aka bloody big mess.
Mark

elf
10-30-2013, 02:04 AM
How about a timber framed hoist: http://www.flickr.com/photos/photo-maniac-spady/8111044720/

PStechPaul
10-30-2013, 02:32 AM
You can probably get an elephant for peanuts... ;)

I think pipe would work OK. It would look something like a playground swing-set. Two A-frames and a cross-bar, with some braces to make it stable. You might be able to get scaffolding pipe and connectors which fit together and come apart quickly. It is also sometimes called structural pipe, and you can get many different sizes and a variety of fittings.
http://www.mcmaster.com/#clamp-on-structural-framing/=p5nfyq

Check out Kee Klamps:
http://www.simplifiedbuilding.com/store/components/kee-klamp.html

Something like this could be built from similar pieces of wood:
http://www.nationalladder.com/GH2T-Gantry-p/gh2t.htm

The Artful Bodger
10-30-2013, 02:41 AM
Hi Plunger, have you considered shear legs? Easy to make as you just need three poles and the principle is as old as building the pyramids.

Dennis WA
10-30-2013, 07:15 AM
I agree that a tripod shear legs is the best solution for a one-off. It has the benefit too of being portable.

Sun God
10-30-2013, 07:39 AM
Shear legs = two poles
Gyn = three poles

But either of those could be fabbed simply from heavy walled pipe that I would imagine could handle a ton, but it would come down to the staying, and how well the stays are anchored.

If lifting heavy items off your truck is something you anticipate doing semi frequently, it may be worth fabbing up a pair of easily removable shear legs that fit on the tailgate and can be swug over the load. If it is stayed at one end to the truck and at the other end to something solid, with come alongs, you can winch it to lean over your load, lift the load, then which it back the other direction over the back of the tailgate. Does that make sense?

jep24601
10-30-2013, 08:05 AM
I think a folding engine cherry picker is your best option. I just bought a used one for $100 to replace my fixed leg cherry picker which does take up too much space. The folding one is not HF and is far more manoueverable and takes up very little space. You would then of course be able to use it at any time in the future. Also, unlike some of the fixed lifting options being described, the engine cherry picker can move with the load.

J Tiers
10-30-2013, 08:38 AM
For one-off, the tripod of wood is great, the wood is always usable later, and should be available nearly anywhere.

The big problem is the angle is crazy to pass 2.5m at the height of the truck bed, or else the thing has to be very tall. I can see wanting to use a gantry type unit.

Problem is that a heavy wood beam for the gantry might be a little less common than material suitable for a tripod.

Is the engine (presumably the tractor engine) actually a tonne? Because then you want to be able to lift somewhat over that, say 2t, just for safety.

firbikrhd1
10-30-2013, 09:04 AM
I don't know much about Africa but here in America the term "shade tree mechanic" comes to mind. The term came from people using trees and a block and tackle to remove and replace engines in vehicles. I'm not trying to be snide when I suggest this, it's easy to overlook the simplest solution sometimes. It is for me to do so anyway. So, if the is a tree available it may do the job for you.
One other suggestion. I have made a tripod out of construction lumber scabbed together and lifted engines. In the end the lumber was used elsewhere. A tripod isn't the most convenient thing because one leg always seems to be in the way, but for a one time use you may be able to deal with it.

metalmagpie
10-30-2013, 09:25 AM
Old idea: make one from pipe. Top horizontal crosspiece has short vertical pieces welded to the ends. Legs are made in a 'T' shape.
To assemble, lay both legs down. Slip top crosspiece's vertical sections over the top of the legs. Restrain the assembly from moving, then chain the top piece to your vehicle and pull the hoist nearly vertical (being careful to not go over center). Then turn both legs 90 degrees to achieve stability. Cheap. Quick. Dirty.

metalmagpie

vincemulhollon
10-30-2013, 10:12 AM
should be 2meters high minimum.

Dig a hole (a ramp) and park the truck in the hole and suddenly that 2M minimum is 0.5M minimum. Sometimes that helps. Might help when you reinstall the rebuilt engine. Most land isn't perfectly flat you probably won't have to dig the whole ramp by hand. Cave ins are going to be a problem.

Duffy
10-30-2013, 10:20 AM
I dont know about South Africa, but in Kenya, 6m gumwood poles are common as dirt. Three of those and a tackle block. Better yet, a good-sized gum tree with a stout limb.

jep24601
10-30-2013, 10:29 AM
Gum trees are subject to sudden limb failure in apparently healthy trees. Better to use a Nandi Flame tree.

jlevie
10-30-2013, 10:34 AM
I would go with a fold up (for storage) rolling engine hoist. You'll probably find other uses for it. Mine gets used a lot more for things other than hoisting an engine. My next choice would be a pallet jack and a ramp.

jep24601
10-30-2013, 10:57 AM
I would go with a fold up (for storage) rolling engine hoist. You'll probably find other uses for it. Mine gets used a lot more for things other than hoisting an engine.

Couldn't agree more. The last thing I used my engine hoist for was lifting a heavy gate out of the back of my minivan. Although I have a gantry and a forklift the engine hoist was the only piece of equipment that could do the job because of the position of the minivan lift gate.

Boucher
10-30-2013, 01:43 PM
When in school and broke, I used a 3/8 chain loop around a light pole on the edge of the parking lot. Cut a notch in ends of a 4x4 piece of wood. Set that against the pole 5 ft below the loop and a chain hoist to the chain below the beam. Picked up the engine and rolled the car out and the new recipent back under the engine and reinstalled.


Speaking of shade tree, I also picked a 3,000 lb fuel tank with a chain hoist using an oak tree limb. Pulled the truck out and set the tank on the ground.

The Artful Bodger
10-30-2013, 02:00 PM
Shear legs = two poles
Gyn = three poles

..... according to Wiki.

Westline
10-30-2013, 02:53 PM
Hey Plunger

It's a bit bulky but for a cheap one time solution I would go with scaffolding (used it to put the work mill on it's stand a while back) you can get it from Hire it for R150 a day, or just park the pickup on West or Smith street Durban overnight and someone will remove it for you.

Best of luck
K

ldbent
10-30-2013, 03:13 PM
A tree works very well if you have one available. I've tripled up a garage rafter with 2 X 6s and used 2 X 6 uprights straddling the truck.

Dr Stan
10-30-2013, 05:38 PM
Do you have a buddy with a backhoe or a forklift?

If not I'll 2nd, 3rd or whatever the tripod idea. Just make sure you fasten the legs together at or near the bottom to keep them from moving on you under load. I'd use log chain and chain hooks welded to the posts for stabilization.

I also recommend reading the information available at Anvil Fire, a blacksmith's site, as it has some very good info and safety tips. Go here: http://www.anvilfire.com/health-safety/load-moving.php

mike4
10-30-2013, 09:49 PM
Plunger ,
Does you vehicle have a tow bar with a removable tongue?
If it does there are a lot of sites for cranes which mount in the standard tongue , you may be able to make something that would lift the motor using the sites for ideas.

Michael

Sun God
10-30-2013, 11:01 PM
..... according to Wiki.

According to my father, the steam-era merchant officer, who enjoyed teaching all sorts of useful rigging lessons.

cameron
10-31-2013, 12:28 AM
3 poles may make a gyn, though I've never heard it called that, not that that means much.

However, a gin pole is a single pole with stays, and often the simplest and easiest to rig for a simple one-off lift. You can usually find a few handy buildings, trees or vehicles for anchors.

The Artful Bodger
10-31-2013, 01:16 AM
According to my father, the steam-era merchant officer, who enjoyed teaching all sorts of useful rigging lessons.

My copy of the Concise Oxford Dictionary says "hoisting-apparatus of two (or more) poles attached at or near top and separated bottom for masting ships or putting in engines etc.,"

plunger
10-31-2013, 01:32 AM
I thought about thre three pole idea but I have roof to deal with on both sides. At the farm I used the roof truss which was a gumpole but I had the head off. It creaked like crazy. This side I have been doing it off roof trusses but I have braced them to beef them up

The Artful Bodger
10-31-2013, 02:01 AM
If you have a shed that can be used to stabilise a gantry. Fix a poles/beam etc alongside the existing roof truss (gumpole) and put posts to support the ends, the posts would ideally be as close as practical to the width of the bakkie.

Forrest Addy
10-31-2013, 02:30 AM
A point of definition: not all cranes are gantrys. A gantry crane in the sense a small shop owner would use the term has a beam supported at the ends by strutted A frames. It's usually fitted with wheels or casters for mobility. A hoist is fitted to a trolley that rolls along the beam. It typically has one axis of load traverse - along the beam - but the wheels or casters allow freedon of movement over the available surface. It's simple, versatile, low in cost, easy to make and is therefore popular where ever safe portable lifts have to be made in the midst of a largish level area.

Here's a whopper: http://i01.i.aliimg.com/photo/v0/250628919/Rubber_tyre_gantry_crane.jpg.

Here's a much bigger one at Newport News VA; over 1000 tons:

http://articles.dailypress.com/2012-07-05/news/dp-nws-shipyard-crane-wars-20120705_1_largest-gantry-crane-tons-matt-mulherin

I think the monster spans 400 ft.

There are many basic crane types identified here:

http://en.wikipedia.org/wiki/Crane_(machine)

OK, back to topic:

Africa? Prevailing stereopypes suggest minimum resources in places far from suppliers?

Got trees? Here's low technology:

Make a lifting horse - a wood structure much like a saw horse ut scaled to suit the span and height needed for the lift. A suitable lifting horse can be made of logs frapped (lashed in the nautical sense) with rope. Diagonal struts can be pegged.

The size of the logs/timbers etc used for stressed members depend on species as well as span and load. Work according to resources, needless to say.

Alternatively, three straight 200+ mm dia logs 7 to 9 meters long can be arranged in a tripod, frapped with rope. Suspend the hoist from the lashing at the apex. The legs have to be splayed to allow passage for the truck and fitted into shallow pits so they don't scoot when under load.

Here's an excellent tratment of the topic

http://www.ropeworks.biz/reader/tripod.pdf

These expedients cannot be moved under load. Place them where you wish the load to be spotted so the loaded truck bed can be backed under the hoist, lift the load, and drive the truck from under it.

Safety... all the way. Right?

mike4
10-31-2013, 04:58 AM
I still think that a heavy duty hitch mounted crane would be something that you could make and possibly even adapt it to allow the use of an engine crane which could easily be made to swing , there are quite a few on the web .
I would look at these for ideas at least .It may be just a one off thing but you seem to be a guy who could knock one up from materials around your shop .
Michael

plunger
10-31-2013, 05:56 AM
Mike a crane might work . If I mounted a upright on my back bumber that could have a brace to the floor and if it had a boom of sorts with a ratchet type chain hoist I could lift the motor up and swing it on a bearing of sorts untill it is over the side of the bakkie(pick up)Then I could just let it down on the loadbin and vica versa

Guido
10-31-2013, 01:24 PM
I always thought it great that an enterprising motel owner in Wendover, Utah (Bonneville Speedway) rented the end unit of his motel for an extra buck per night, so's the racers could work on their cars. The porch on that end unit had a nice 6 x 6 horizontal timber, from which a chain fall was temporarily installed during race week.

Real irony was that across the highway, a deep pit was constructed in the floor of an aircraft hangar, of which a B29 bomber could roll over. There, the first air dropped atomic bomb would be loaded up into the belly of a bomber.

plunger
10-31-2013, 03:40 PM
Hey Artfull Bodger you will confuse everyone with the terminology of BAKKIE.( Thats not a kiwi word.:)I actually find it incredible when you look at some of the crains in forests link that they actually stand up under load.Alot of thought has to go into some of them as they look real dodgy. I have always been amazed at the strength of hydraulics and when you look at how thin the rams are and what they can actually lift is amazing. I think the Chinese gantry or hoist with the wheels will serve my purpose well

The Artful Bodger
10-31-2013, 03:49 PM
Hey Artfull Bodger you will confuse everyone with the terminology of BAKKIE.

They get confused if I call it a "ute" too!;)

Those chinese 'engine lifts' look good in the shop but are less attractive when you come to use them for anything but putting an engine in a vehicle. You cant even get something heavy out of a ute (or bakkie!) unless the load is right at the back and most of them have only limited lifting capacity unless the upper arm (I hesitate to call it a 'job'!) is used in its shortest setting which in turn means there is only a few inches of lifting available.

firbikrhd1
10-31-2013, 09:05 PM
Reading these posts gave me another thought. In my previous occupation we used heavy duty aluminum straight and extension ladders lashed together at the top to form a ladder A Frame. We also set up ladder gins, both for lifting victims from areas where other means could not be used. If you have a couple of heavy duty ladders they could likely be set up as described to lift up to about 600 pounds.
If you have interest in attempting this type of operation, Google Technical rescue and Ladder A Frames or Ladder Gins. You should be able to find good rigging instructions there.