DIY Gantry Crane

[BrianGreul]

I have needed a heavy duty crane for a while. So last week I decided to build a hydraulic gantry crane. I shot several videos of the crane in use, being built, and the design planning.

Disclaimer: Lifting heavy objects is very dangerous. If you are not confident in your welding and fabrication and design abilities please don't do it. Lifting thousands of pounds can create a situation which could cause serious personal injury or death.

Now that you have been warned, this crane is designed for 5,000 pounds but could probably handle 9,000 based on the beam strength from an engineering calculator.

I used inexpensive, off the shelf hydraulic rams from Harbor Freight ($30/ea on sale). About $450 worth of steel and $80 of wheels from Northern Tool.

The wheels are mainly to make it easy to move on rough surfaces.... you could adjust the wheels to be smaller or to be on parts that flex and remove the load when you lift. The wheels are rated for 1,000 pounds each but I found on a smooth surface I'm able to move the crane loaded which is a huge bonus for me.

Build Video:

Planning Video:

One of the videos showing it in use:

Playlist of all DIY Gantry crane related videos:
https://www.youtube.com/playlist?lis...e_polymer=true

[metric_taper]

Somewhere a miracle occurred, from seeing the video of skidding the Monarch onto a skid, no video of seeing it loaded into the box truck (I went to the youtube channel and this step is missing). That had to be interesting.
Also, this lathe may be tough enough to lift from the spindle, but in newer lathes with large through holes, that could end up bending it beyond use.

[BrianGreul]

Somewhere a miracle occurred, from seeing the video of skidding the Monarch onto a skid, no video of seeing it loaded into the box truck (I went to the youtube channel and this step is missing). That had to be interesting.
Also, this lathe may be tough enough to lift from the spindle, but in newer lathes with large through holes, that could end up bending it beyond use.

Not sure why you had trouble finding it..... 42 minute video:

There is a bit missing due to a camera misbehaving, but the overall process is there.

The balance point is under the spindle. Lifting by the spindle would damage it. We passed the sling around the spindle and through the ways. There we blocked it with wood. So all the lifting force is under the ways or bed. This is how the 1941 manual shows to sling the lathe.

[BrianGreul]

This particular video is in the play list: Moving a Monarch Lathe. I didn't consider it DIY Gantry Crane related.

[metric_taper]

I looked at your video list on youtube. You have a broad range of hobby's.
I see this video in the list. Looks like you used pull back truck winching it on its hydraulic platform. Then transported to the box truck.
You have a video saying you rented the box truck. Do you own the hydraulic platform truck? Seems you used it to move your Bridgeport.

Anyway that sort of truck was used to deliver my 5600lb lathe. I paid a local crane company to off load the lathe from the shipping terminal, then to my shop. They loaded the lathe with a fork lift to move it down a gravel driveway. The operator had machinery skates to place it in the shop. It was worth the price.

[NeiljohnUK]

The wheels are mainly to make it easy to move on rough surfaces.... you could adjust the wheels to be smaller or to be on parts that flex and remove the load when you lift. The wheels are rated for 1,000 pounds each but I found on a smooth surface I'm able to move the crane loaded which is a huge bonus for me.

Having seen the end result of a loaded gantry overturning when a small stone got caught under a wheel I'd rather only use the wheels for unloaded movement, experience can be an awfully hard and painful teacher, luckily no-one was killed
.

[BrianGreul]

A standard flat bed roll-back wrecker.... Just one of many things they do.

[BrianGreul]

Having seen the end result of a loaded gantry overturning when a small stone got caught under a wheel I'd rather only use the wheels for unloaded movement, experience can be an awfully hard and painful teacher, luckily no-one was killed
.

Fortunately, physics is a great way to understand the effect of forces. While it's possible to over turn a crane, the simple physics of a 5,000 pound weight make the leverage required to turn over the crane impossible. Even if you succeeded in somehow doing that, the lathe would crash down the couple of inches at most that it was off the floor.

In this particular case, the wheels are primarily for repositioning and storing the crane. However, if the wheels are oriented properly and it is an absolutely smooth surface, the crane can be moved within my garage. This is particularly helpful for repositioning the lathe. At low speeds and barely off the floor any tragic accident is highly unlikely.

The minimum design was around 5,000 pound lift. The material that was available was much heavier. 25% to 100% heavier depending on the component. The net effect is that the as-built rates out at 9,000 pounds. So it's well within the safety margins.

[NeiljohnUK]

Fortunately, physics is a great way to understand the effect of forces. While it's possible to over turn a crane, the simple physics of a 5,000 pound weight make the leverage required to turn over the crane impossible. Even if you succeeded in somehow doing that, the lathe would crash down the couple of inches at most that it was off the floor.

Indeed the height is key and having a low enough CoG, the incident I had to investigate involved a 3m tall 2,000 Kg stainless steel cactus sculpture covered with sharp steak knives, they got lazy and rather than 'run the beam' then reposition to run the beam again 4 or 5 times they decided to push it along. They were very, very lucky neither the sculpture nor the gantry or block hit anyone, the sculpture was scrap.

[Ralphxyz]

IN the original (first) videos you had a Box Truck on your last video of actually loading it you have a Flatbed, maybe you explain what was going on but I just skimmed the videos.

Ralph