Mobile Gantry Crane Build

the ultimate modular adjustable portable mobile super gantry warning building or modifying lifting equipment is dangerous you have been warned [Music] i'm going with this mobile gantry design with braced corners and telescopic legs the clear span between the a-frames is 2.7 meters to allow future truck access if required i want to make this thing modular and portable so the top rail will be bolted to the upright legs i can't really be bothered drilling this by hand so i'm going to use the drill [Applause] press this beam's upside down the upright connects here with the plate this edge distance isn't very much there's not much material to prevent this tearing out here i don't see this as an issue there's no sideways forces but something to be aware of something i want to add at this support is a stiffener in here if you look at an i-beam it's really just three flat plates joined together each of these plates can undergo localized deformation and buckling so a stiffener helps resist this if you get a long enough beam the beam wants to roll over onto its weaker axis limiting the capacity adding a stiffener over the supports at each end partially resist this effect so yeah we're going to add stiffness [Music] the beam has a radius in the corner so i need to snip these corners off to make it fit [Music] let's start looking at making the a-frames and the legs [Music] these long pieces of steel are hard to manage so i'm initially chopping them apart with the angle grinder and then tightening up the ends on the bandsaw these two tubes are going to make the upright legs and these will be telescopic i have a larger size tube so these legs can move up and down i couldn't get telescoping tube sizes close enough to what i wanted so this is a little bit loosey-goosey however i'm going to weld some flat bar on here once i pack this on a couple of sides it's a very snug fit so here's where i'm at i've got these tubes so these are a bit tight inside the matching sleeve now at the moment i've only got the flat bar on the front side and not the back and that does mean these are a bit loose we'll tackle that later in the build let's look at putting the locking holes in the legs so thank you patreon supporters so while i set up drawing these holes in the legs i also drill holes in the matching telescoping sleeve so let's use this and start putting together a frame [Music] before i weld this together and make it hard to handle i'm going to drill and tap some holes in the base i've done some world prep on all these joints and stripped off the galvanizing complete fluke but i seem to have a good spot on my floor if i push these together everything lines up really well there is still galvanizing on the inside of these tubes i'm gonna have a fan going while i'm welding this is all tacked together now i want to go through and work from the bottom up and finish on this joint last this is the most critical joint in the entire structure so i want to go through make sure i've got my world settings right and work on this joint [Music] last [Music] these frames are done i want to bolt the casters on here and stand these up so i'm sick of kneeling on the ground i've got these casters they're made in italy so how do you work out the load capacity it's a lifted load divided by four right wrong no doubt you've seen a wobbly bench it rocks on two of the legs but it will find three points of contact i can pretty much guarantee this gantry is never going to be sitting on a flat surface with all four casters engaged so lift it load divide by three technically yes i'm going to be using a girder trolley on this beam so if it shifted all the way towards one side effectively two casters will be engaged i don't ever expect a heavy load to be all the way towards one side i've got extra capacity in those casters in case i need it i'm going to put some loctite on these just to help prevent them dropping out these casters have an important feature brakes back to assembling the legs i'm close to standing this gantry up but first of all i want these braces installed in the corners to drill things easily and safely on the drill press this is the method i've come up with if you spot all the holes first this becomes so much easier if you spot it line it up you get some locking pliers done good to go brilliant things after drilling pilot holes i repeat this process with larger drill sizes these will form braces that reinforce the top corner of the gantry two different plates one connecting to the beam one connecting to the leg you might have noticed by now i'm dragging all of my welds i'm using gasless mig if it makes slag you've got a drag so mistakes have been made these whole centers are 110 mil these are 120. i don't have enough plate to remake these and i don't have a die grinder to slot this out so i'll do this at the mill [Music] i didn't really have any way to properly get this angle correct what i can do is break this world through here angle this bracket down until it makes contact with this leg and then i'll drill the holes for this so this brace goes on here where this brace connects to this leg there'll be a lot of bending and having these holes means i've weakened this leg quite a bit so i need to plug up these holes i could just put some plate in here and fix up what i've taken out but i made up some pins on the lathe effectively putting a stiffener in at these locations so the legs actually stronger than it was to start with [Music] so it's starting to turn into something quite big i'm going to use a boat winch on each leg it was cheap and it's certainly got the capacity one place i could put them is right here i can then wind the strap down to the bottom of the leg and pull the leg up from the bottom this strap will be tight under the load of lifting the gantry and i need to be able to get a locking pin in these holes so that's going to limit access there coming further down the base here if i mount the winch here i'm going to run into issues with the handle but i'm thinking if i turn the winch sideways i then got plenty of room to operate the handle and now i can then have a plate to bolt onto the back of this winch so the holes in the legs are at 100 mil centers but in the base i've got these holes at 50 mil centers this means i can set the height of the legs anywhere within 50 mil you can see a hole here this will drop down to this hole and the next hole in the leg is up here i think now it's time we start looking at making some proper locking pins so to lock these legs off all of the load needs to transfer through these pins this pin needs to be large enough diameter that the pin doesn't shear putting it through both sides of the steel tube doubles the capacity of this what is limiting this connection is actually the tube it's so thin that this pin could actually tear its way through the tube having a large pin and a large hole means that the load is transferred over a wider area and that means the contact stress is less i have three main problems with these braces one they're time consuming and difficult to install two these bolts here are only tapped into this tube i'm only getting about two threads engagement which i'm not really comfortable with and thirdly the plate on these braces bottoms out on this bottom section so i can't lower the gantry all the way down because these are difficult to remove i don't want to unbolt it every single time i want it down low i've got an improved design these plates will belong here but before i do that i want to work on the other end while i still have the plasma out i cut these holes in hindsight i should have used an annular cutter quickly made up these in the lathe and these will go here and this will form a hinge i've put a hole in where these are going to go this red section here is about where the pins are welded in earlier and i'll just position it there the other braces have thicker plates but this time i've got two cheek plates on either side so i don't need to go as thick this gantry is getting really close now but remember how i said earlier this telescoping fit is a bit loose yeah we need to address that i think this is a pretty simple fix if i have a set screw that drives this leg hard against the sleeve it should be a lot more rigid loading it like this at the moment we're twisting the hook and this is not ideal [Music] so i'm using an eye bolt and i am side loading eye bolts are not really designed for side loading unless they've got this collar here normal eye bolts only take axial loads collared eye bolts can take side loads to a point the capacity of an eye bolt drops by a quarter when you side load it like this if you wanted to go for the style of gantry where you're winching up the entire load from the bottom of the legs this eyeball would have to be absolutely enormous which is one of the reasons why i'm not going that way as it is right now this gantry is in the maximum height that will fit out the door and as you can probably tell i'm gonna struggle to lift the mill one problem i'm having lifting slings never come in the right length for an application like this so i've got some lifting chains with some chain shortness so these are proper lifting chains with chain shorteners this just lets me shorten up chains by hooking the links onto this in this lifting chain it has these hammer locks and normally it has a master ring that goes in the top this is robbing me of a lot of height now i'm removing rated lifting gear but i'm replacing it with a rated shackle but it's still not enough i'm going to completely remove the chain block and i'll come up with a way of jacking the legs up and then i'll be able to move this mill i need a way for this bottle jack to push this leg up so i need a cap hydraulics have some issues they can leak and they can let go so what i plan to do in operation is to jack the load up pin the leg off i'm never going to move the gantry with the load suspended on hydraulics i've lifted this leg up and you can see that we're about to run into this eye bolt here so i've got a problem we're at the limit of the travel of this leg that's no good this isn't high enough when i put this end cap on i tapped a hole in the bottom i've made up these extending struts and this lets me pull the leg up even higher this has also been made modular it's got the exact same tap hole in the bottom of this so theoretically i could extend this again i've also got tapped holes in the side here and this lets me pull the leg up from down here now this extension is small enough to fit inside the main tube of the leg this can be fully sucked up inside this frame to give me a lot of extra height now there's another mode of operation for this extender if i put a bottle jack under here i can now use this to push the whole gantry up this 500 kilo mystery crater ride and makes a perfect first test i was able to unload this in half an hour where once it would have been a full day operation plus one to the gantry now to try the mill there is one more cool feature but i'll show it after i move these machines around they're all the same length i'm moving this mill from one section of my workshop to another it's really only moving about 10 meters there's no access for a machine between the two areas i have to transport the gantry and the machine around to the other side of my workshop i made up a cradle to go on the trailer and this lets me move the mill and the gantry at the same time [Music] the gantry can drop down to 1.8 meters overall height and the reason is this door here and to be honest in the end the gantry wasn't used to lift the mill directly the mill was hooked up to the gantry the whole time and this gave me an extra safety line in case something went wrong trying to show out the final feature of this gantry it's really big it dominates my workshop honestly it's in the way i've got a solution the final feature of this gantry is this hole here what i can do is turn the leg like this push it up against a wall secure it turn the other leg push that up against the wall i've got a flat pack gantry against the wall the other crazy thing this lets me do this is really narrow now and just as tall as i am so technically any doorway that i can walk through this can pass through so you wheel one end through turn it sideways turn the other end narrow wheel that end through and stable the whole time i don't know how useful that will be but it's a pretty cool feature anyway thanks for watching supergantry soup again

Channel: Tom Make Here

Views: 15,378

Rating: 4.9174485 out of 5

Keywords: crane, gantry crane, gantry, do it yourself, gantry crane build, portable gantry crane, gantry crane operation, mobile gantry crane, crane build, fabrication, welding, mig, machining, engineering, lateral torsional buckling, web buckling, lifting equipment, AS4991, AS 4991, chain block, winch, hydraulic jack, hand winch, Tom.make.here, Tom make here, Workshop, Bandsaw, super gantry, mobile gantry, portable gantry, diy crane, diy gantry, workshop gantry, homemade gantry crane

Id: Th8EjnvPjVs

Length: 20min 52sec (1252 seconds)

Published: Thu Apr 08 2021