[TraditionalToolworks]

Thanks Alan. Yeah I had seen the variant of a gantry that slid along rails. I decided against that option (WAY against), as it just wouldn't fit my use case scenarios. I needed the gantry to move wherever I needed it to move, however I needed it to move. And so I decided to put it on wheels, just like a vehicle. Or in this case, more correctly like a trailer, as the hubs, wheels and tires are designed with trailers in mind.

Go the bigger caster route then, and if you have to put plate under them when it's under load.

[av8or1]

Then it was time to fab the suspension:


Which consisted of the usual large bevels, 6010 root passes and 7018 fills/caps. All triple pass welded at a minimum. One of the 6010 passes, which had a restart in the middle as I recall:

[av8or1]

Thanks Alan. Yeah I had seen the variant of a gantry that slid along rails. I decided against that option (WAY against), as it just wouldn't fit my use case scenarios. I needed the gantry to move wherever I needed it to move, however I needed it to move. And so I decided to put it on wheels, just like a vehicle. Or in this case, more correctly like a trailer, as the hubs, wheels and tires are designed with trailers in mind.

Go the bigger caster route then, and if you have to put plate under them when it's under load.

That's a decent choice, sure. But nah, I chose to go with actual wheels-n-tires, as y'all will see in a bit...

[av8or1]

Beveling picture, pre-wire wheeling:


Some 7018 passes visible here:


Since I had an outer plate created at the steel supplier, I decided to weld that onto the outside of the c-channel for additional (but 'prolly unnecessary) strength. Overkill at work again dontchaknow.

[av8or1]

Since the spindle mount of the hubs from Northern Tool were 2" in length, I decided to weld-in another support plate, but this time to the inside of the c-channel. However I didn't put this inner support plate immediately adjacent to (ergo "butt-ed up against") the channel. Instead, I offset it a bit to the inside, thus:

inner supports 2.jpg (55.2 KiB) Viewed 37176 times

The notion being that it would provide extra stability to the spindle mount, kinda akin to how you put that second hand on the back of the chainsaw. It gives you more control and is much easier to operate than if you only had a single hand on that saw. The astute viewers might notice that the holes in the panels don't quite align. And you'd be right. That was intentional, as I decided to design a positive camber into these wheels from the outset. And that is akin to what you would see on the front suspension of old tractors, thus:

[av8or1]

This configuration will allow the gantry to roll better and to steer better. As it would turn out, I went with an almost-5 degree camber:

axles 3.jpg (43.57 KiB) Viewed 37189 times

And with more work, all 4 were welded, put into primer and then painted in burnt orange:


ps-Attaching pictures now rather than pointers to third-party picture hosting, as the latter is being chopped off for some reason...

[av8or1]

It was then time to install the leg mounts, which are the means by which the suspension would be attached to the gantry's legs. They were significantly beveled too:


Both on the ends and the sides:

[av8or1]

I ground the paint off and applied weld-thru primer:


Welded them into place, then applied rusty metal primer:

mounts 11.jpg (35.36 KiB) Viewed 37188 times

[av8or1]

These mounts have obvious structural importance, and so the sides and bottoms are triple pass welded as per the aforementioned formula. The tops (and bottoms respectively, depending on which mount you are referring to) have a 6010 root and as many 7018 passes as I could weld without causing a fitment issue. I think at a minimum that resulted in about 7 passes over the 6010 root. A couple of them had 8 or 9. "Just bead after bead after bead" as Jody says.

Alright so to skip ahead a bit, my son and I painted the new stuff and then the day came to mount the lot to the gantry. I laid everything out to take account of what I was about to do:


And then got to work. In the end, they came out well:

[av8or1]

This suspension type has full 180 degree range of travel from the inside of the legs:


To the outside:

[av8or1]

However I noticed that my suspicion of the gantry being difficult to move was correct; that was because the wheels would wander into contradictory positions. I'm sure that behind the F-450 it would be no problem, but I wanted the ability to move it easily by hand. And so I busted out the magnetic drill once again:


To create holes through the suspension and the mounts through which a pin could be inserted. This locks the suspension in a given position:


And that solved the problem. The gantry then moved easily by hand and didn't stop rolling even when it went onto the grass! Hah! I had to pull it to a stop once I had it moving. And so I called that a success.

[TraditionalToolworks]

That looks like it will work well. Inflatable tires have their pluses and minuses...

[av8or1]

A couple of more pictures:


And:


In case you are wondering, those hubs are rated at 1,750 lbs each, thus 3500 lbs per "axle". The gantry itself is rated at 1 ton with a safety margin of 5 or at 2 tons with a safety margin of 2.5. I stopped running the numbers at 10,000 lbs, by the way. I won't use this for anything anywhere NEAR that, and so a 2 ton crane more than meets my needs. At the 10,000 lbs mark the deflection in the main beam was still within max allowed, so I'm sure it could do more. But I didn't care. Knowing that I have way-more than enough suits me just fine...

Thus in the end, I developed and will employ a rather straightforward usage formula:

Lift anything 1-ton or less = wheels
Lift anything heavier = casters

Should work out ok.

Thank you for reading.

[av8or1]

That looks like it will work well. Inflatable tires have their pluses and minuses...

Indeed. I wouldn't have gone this route save the need to operate in a relatively rough outdoor environment, running over uneven and very-much-not-smooth surfaces. But that is the case in this application context. And these wheels move over those surfaces easily, no issues. I like being able to move it by hand through the grass, although doing that requires a bit of applied muscle force.

Thank you for the feedback!

[TraditionalToolworks]

Nice looking piece of property!

[BugHunter]

Nice job! That's gonna be a handy trinket in years to come. I have a similar one though not nearly as heavy duty as yours. Mine was built for putting heavy parts in the lathes but is also used for unloading materials off trucks as well. We built that with round uprights, heavy casters and a c channel for the main cross member. I lifted my car off the suspension with it, but there wasn't much car left to lift with engine, torque tube, trans, rear, cradles and suspension removed. Lol.

[homeboy]

That looks like it will work well. Inflatable tires have their pluses and minuses...

Indeed. I wouldn't have gone this route save the need to operate in a relatively rough outdoor environment, running over uneven and very-much-not-smooth surfaces. But that is the case in this application context. And these wheels move over those surfaces easily, no issues. I like being able to move it by hand through the grass, although doing that requires a bit of applied muscle force.

Thank you for the feedback!

-- All you need now is to rig up a wagon style steering setup with hinged tongue and you can go mobile.

[homeboy]

That looks like it will work well. Inflatable tires have their pluses and minuses...

Indeed. I wouldn't have gone this route save the need to operate in a relatively rough outdoor environment, running over uneven and very-much-not-smooth surfaces. But that is the case in this application context. And these wheels move over those surfaces easily, no issues. I like being able to move it by hand through the grass, although doing that requires a bit of applied muscle force.

Thank you for the feedback!

-- All you need now is to rig up a wagon style steering setup with hinged tongue and you can go mobile.

[av8or1]

Popular when you have a gantry crane.

Neighbor needed to lower his boat motor again:

IMG_20092020_170648_(920_x_690_pixel).jpg (91.82 KiB) Viewed 37055 times

[Poland308]

Hope you at least got a beer to drink while you watched him work!

[av8or1]

Hope you at least got a beer to drink while you watched him work!

Yeah I chose to let him attend to the business at hand. That way if something went awry he would only have himself to look at for answers.

I'm from TEXAS and my preferred drink happens to be sweet tea. And yes, I downed a complete cup watching him work.