OVERHEAD LIFT QUESTION

[rlrsk8r]

I have a new garage with a 12 foot ceiling and want to store my zero turn mower, weighing about 1500 Lbs in it this winter. My plan is to build a rectangle-shaped spreader bracket out of some 1-5/8 in.² tubing with 0.150 inch wall thickness.
The bracket will be a rectangle that is as long as the zero, and as wide as it so the chains attaching to the 4 corners will hang straight down. I plan to put a crossbar across the middle-ish of the lift bracket to lift the frame which will in turn lift the mower.
I plan to fix a lift EYE to the ceiling trusses which support the attic floor above (2x10 bottom chord). Chain hoist to lift the zero-turn up to the ceiling for the winter. I have some heavy industrial chain with hooks on it to support the zero turn.
I have looked for calculators on the net to see how much the tubing will lift without permanent bending, but have been unable to find the calculator for that.
I am not a mechanical engineer, so I don’t understand the formulas for steel structures and how to calculate load limits.
Can somebody help me please. ?

 

[4570Man]

I’d use 2” 1/4” wall tube that I know would work without having to engineer anything. The lighter tube would be marginal. I’m not sure that hanging it from a single truss is a good plan either.

 

[zzvyb6]

I don't care for the hanging frame notion because of the wooden beam materials. If & when they dry out, they will weaken, split, and possibly damage the building's roofline. Your 1500 lb mower PLUS the chains, plus the chainfall, plus the frame may put you at 500 lbs per corner. I went with a used 2 post car lift anchored securely to the concrete floor. I added 2 trough ramps at axle width dimensions onto the sides arms, drive the mowers on, and store or maintain oils, clean up the deck, change blades, whatever is needed. It obviously also serves many other purposes for all my vehicles, mowers & tractors. $2000 installed plus $1000 for the special, reinforced extra strong & thick concrete base.

 

[mrmikey]

I'd be a bit leary of hanging that much off the bottom chord of a truss, they're not made for vertical load.
Saying that, I do have three lifting eyes running front to back in my garage for light lifting but not for permanent storage. I ran a 2 x 2 x 1/4 HSS across the top of the bottom chord of 6 trusses. I also tied it into the top chord of each truss with a 2 x 1/4 flatbar so it's in tension. I went thru the ceiling with 2 pieces of 1/2 threaded rod bolted thru each anchor plate with an eye on it for a set of come alongs.

 

[mikester]

Buy a used forklift. You will find it cheaper and way more convenient.

Get one with side shift!

 

[LD1]

I would analyze the building first.....way too many details left out to even know if its a good idea.....but in general....trying to hang a mower from a wooden truss....sounds bad.

But the plan you describe with a single point lift....dont even know why you would need a spreader bar....

Guess I dont know your mower....But I could easily find 3-4 points to hook a chain, find balance point, and hoist my mower without some spreader contraption.

But still not even enough info on the steel. Need lengths to be able to determine loading and deflection. You provide no dimensions at all

 

[rlrsk8r]

The spreader bar is because the two tiedown eyes I put on the back of the mower are located under/just behind the two plastic gas tanks and I do cannot have anything pressing against those plastic tanks for the long term storage.
It's a Hustler Zero mower is so you can look up pictures on the net and see my requirement for the spreader. Maybe I don’t need vertical orientation of the front chains which I had not thought about but thanks for mentioning that, LD1. I installed the 1/2' - 13 tiedown eyes on the corners through the square tubing frame of the mower for tiedown points for hauling the mower on my utility trailer. I might now change the final design of my spreader bar I'm using to angle the front chains, but the rear chains still need to be vertical.
The reason for using the material: it’s what I have. I’m not willing to spend thousands of dollars on other stuff just to “overdesign“.
I built the garage last month so I don’t have to worry about age-weakening of the trusses.
Considering hanging the mower from the trusses made me decide to spread the load over three of the trusses. I could have hung from one truss or maybe two but decided to distribute the load over three with them, being only 24 inches on center. My truss support bar across them will be a piece of 3 inch angle iron fastened high on each bottom chord. The angle iron’s ears will be fastened with 3/8” or maybe 1/2" bolts through the chord with 3 in.² stiffener plates under the nuts.
For winter storage I want to get the mower out of the way so that I can use that floor space.
I have also built shelves 4 feet in front of the back wall of the garage using 18 X 36”industrial shelf pans but since I don’t have the steel angle iron legs, I used 2x4s going all the way up to the bottom chord of the trusses. I set my shelves 4 feet away from the wall so that I have additional storage against the wall behind the shelves.
I'm also planning to hang my extended-reach cherry picker (3000# CAPACITY) engine hoist similar to the mower, again, to get it out of the way when I'm not using it. It weighs about 400# and I cannot disassemble it.

 

[WranglerX]

Think you would be better with floor mount 4 post "storage" lift.... Don't believe your roof trusses are designed to be "loaded" as you want to do....Also many advantages of having a"lift system" available for doing maintenance work....

 

[sandman2234]

I have been known to lay a lot of stuff on top of the bottom cord of roof trusses, but never anything as heavy as a lawnmower. Plus you are already adding to that weight by adding 400 pounds of cherry picker, which is definitely a floor space eater by itself!
As most people who have commented seem to think, I also agree that it is not a good idea. The current age of your garage doesn't have as much to do with it as your comment suggested, saying the garage is only a month old. We are assuming that by the time you wear that mower out, the trusses will be "old".
If I were going to do this, (I have welding and fabrication experience) I would build steel trusses out of the 2x2 you have, and support it with 4 posts of the same material. That is going to be a LOT of 2x2 (1.5" that you have?) Maybe a 3 post lift situated in the corner? I learned the hard way that steel trusses (called bar joists around here) do not like to have things hung from them. I hung a 3pt backhoe from one, which held it fine, till someone bumped into the hoe, causing a sideloading to the straight downward force, and it took out the roof in it's entirety. Could have been a lot more expensive, but the actually roof had not been installled over the roof trusses at the time. No way would I have thought that the weight would have done that, just didn't make sense. An engineer friend saw what I had done via pictures and said the collapse made perfect sense to him.
I am thinking that you're going to need to get creative with your floorspace to make additional space, and was wondering if the Cherry picker could be used to raise the mower high enough to clear the car that you are parking in the garage? Legs under the car, mower over the hood? I would be sure to install a cylinder failure device on the hydraulic cylinder so the mower doesn't come down unexpectedly.
David from jax

 

[scootr]

Contact a truss builder if you insist upon proceeding they can better tell you if the trusses will support the load hung from the bottom cord. Note the truss is designed to have an even shared load from the top cord down. Hanging a load from the bottom cord is very different than the engineered application and I think there is a significantly reduced weight capacity there.