Bridge Crane build

[rabler]

I mentioned this in my thread on building a new shop, but I thought I'd start a new thread on this. Shop was finished up early fall of last year. I built the shop with the intention of putting in a bridge crane. In this picture of the shop layout, the bridge crane rails are shown in green on the right half of the shop.



I put in the 8 steel support posts for the crane as the last part of finishing out the shop construction, but held off on the bridge crane for financial reasons. Just picked up the steel to start building the rest of the crane. I had debated a bit on capacity. The side rails are supported by 4 posts each, which works out to be about a 13' span between posts, so it is fairly easy to size beams for capacity there. But the 24' bridge beam is, well a 24' span (actually about 23'). Of course there is no reason that those beams need to be the same size, and they aren't.

I'm not a licensed PE, so I'm not going to go into details on load calculations and beam sizes. I have done the load calculations so I am comfortable with my design but for safety/liability reasons I don't want to get into anything that sounds like I'm giving a detailed how-to on designing a crane. It is my hobby shop, OSHA approved design not required. I understand that probably implies some liabilty exposure. What doesn't these days?! I'll just say I used L/600 as my deflection goal as that is a standard that I found for bridge crane design. I compared that to a 5x safety factor. With those in mind, my crane will have a 2 ton capacity. I had originally considered 1 ton, but the incremental cost is not huge, and 2 ton allows me to hoist my smaller mill and two smaller lathes, which a 1 ton would not. Most of my use will be for 50-500lb items, chucks, rotary tables, or machine dissassembly. For lifting the big lathe, or big mill, I'd need 5 ton capacity, which would mean a motor driven bridge in addition to the cost of larger beams.

This week I picked up steel. Of course, getting 40' beams through a 10' door is not straightforward. Nor is hauling 40' beams. But, that part is done.




It'll be a few weeks before I have another update, I tend to plod along on these projects.

 

[dkemppai]

Nice that you have a truck to be able to haul the steel yourself. I had to have mine delivered.

So, looks like your main rails need to turn 90 degrees to fit into that space? Do you have enough room to do that, or are you going to have to feed it into a window or something silly? (Ask me how I know to ask you... )

 

[rabler]

Nice that you have a truck to be able to haul the steel yourself. I had to have mine delivered.

So, looks like your main rails need to turn 90 degrees to fit into that space? Do you have enough room to do that, or are you going to have to feed it into a window or something silly? (Ask me how I know to ask you... )

Geez, steel the fun out of down the line posts. I'm already planning on the window option. But I wanted them in the shop first to clean up, cut to length, weld attachment points and drill mounting holes, and paint. Then give them several weeks for the paint to harden. Plan is to using the tractor/loader outside, and the small black gantry crane in the last picture above to hold a roller assembly on the inside at an appropriate height.

The full height wall on the right in the last picture is the obstacle. I think it is geometrically possible to angle it over the office on the left while continously turning the beam and moving it forward. Practically that sounds like a recipe for disaster.

 

[Aukai]

I had an 02 Dmax exactly like that one. Only 1 injector in 100K miles pulling a 15,000lb boat 2-3 times a week.

 

[rabler]

I had an 02 Dmax exactly like that one. Only 1 injector in 100K miles pulling a 15,000lb boat 2-3 times a week.

This one is an '05. About 110k miles on it. It rarely goes anywhere without either that trailer or the 4 horse gooseneck attached, used it to move the entire farm from Savannah, Ga to SW Indiana between 2016-2018. Scaled one load at 28,500 total when hauling that trailer with the tractor and a few attachments.

 

[Aukai]

I liked the fact that it also had great stopping power.

 

[rabler]

I liked the fact that it also had great stopping power.

On the trailer, I bought that used. The electric brakes really were bad. Cleaned all the connectors, etc, still bad. Voltmeter check at the drums showed something like 7V when the truck was putting out 13 at the connector. Paralleled some 14 ga wire back to the drums and suddenly had real brakes. Hauling hay, the practical load limit is where the brakes become nearly binary (on or off).

 

[Dabbler]

@rabler I'm about 25% of the way through building my bridge crane. Way to go on yours! Mine will only have a 200kg capacity, as my main beam is 15' 4" X 4" X.250 wide flange aluminum beam. Perhaps I'll start a separate thread on it.

Nice work on moving those support beams. They must weigh at least 425 lbs easy.....

... how much will your bridge beam weigh? -are you using wide flange?

 

[Aukai]

I had no brakes on my trailer, every year the rear brakes were completely replaced, except for the caliper because of salt water.

 

[rabler]

@rabler I'm about 25% of the way through building my bridge crane. Way to go on yours! Mine will only have a 200kg capacity, as my main beam is 15' 4" X 4" X.250 wide flange aluminum beam. Perhaps I'll start a separate thread on it.

Nice work on moving those support beams. They must weigh at least 425 lbs easy.....

... how much will your bridge beam weigh? -are you using wide flange?

Pretty close on the beam weight, yes W beams. 200kg capacity would cover 95% of my use, but designing where I’m at avoids any temptation to exceed the design load.