Safely Move A Half Ton Lathe

joshua43214 said:
I refer you to this article
https://www.extension.purdue.edu/extmedia/ppp/ppp-75.pdf
It conforms to all US DOT regulations for securing a load. It contains numerous photos of properly secured loads, you will notice that virtually every load secured with webbing goes up and over the top applying vertical pressure. Virtually every image showing what you describe is done with chains. Nylon stretches, chains do not.
I will also refer you to this article
http://ohioline.osu.edu/aex-fact/pdf/0598.pdf
From which I quote "If the cargo has a tendency to tip, use a brace."

Strapping over the top does prevent tipping. I have no idea where you get the idea that it does not. By your standards, most of the cargo transported by professional drivers and loaded by professional riggers is done incorrectly. The sideways movement you are referring to during a tip is always accompanied by vertical movement. The wider the base or the wider the top, the more vertical movement during a tip.

Also, I never made the claim the ties to front and back tie downs prevented sideways movement. I even capitalized the word "NOT" as in "...are NOT securing the load." They prevent the tail stock from swinging, as in rotating. With nearly 4' of moment, the tail stock can provide enough leverage to rotate the lathe under the main hold down. The front tie impedes the swing, and the rear tie gives tension to the front tie.

Seriously, if you are trying to use webbing to try and prevent a load from sliding or tipping by using lateral pressure, you are doing it wrong. Friction prevents sliding, vertical pressure produces friction. Using two straps is fine, it is often done. But the principle of producing vertical pressure to induce friction is the same.
Click to expand...

Heaving read the articles:
NONE of the picture show a load comparable to a lathe.
The heavier items in the pictures are the equipment on wheel/tracks, that both have a totally different centre of gravity compared to a lathe/mill.

The rules as depicted in the articles are absolutely inadequate.
The number of ties are determined by length and weight.
The most important factors, height and centre of gravity are not mentioned.

Chains will stretch. (Youngs modulus?)
Be it just a fraction of the stretch nylon will have.

The most important factors are height and width of the base.
Width of the top is a rather unimportant factor as the rise in stress by the tilting up of one side is counteracted by the lowering of the stress because the other side is going down.
The ratio between hight and width of the base will determine how much stress will be put on the tie going over the top when tipping over.
The wider the base the more the top will initially rise putting thereby stress on the tie.
A narrow base, in comparison to the height, will put less sress on the tie.
A narrow base will also act more as a fulcrum for the sideways movement, thereby reducing the sideway force needed to tip over.

Swinging as in rotation?
I believe a rotational movement has two vectors.
The two totalling 90 degree.
And the sideway movement starting at 90 degree and deminishing to 0 degree after a 90 rotation.

I wont say most professional riggers make a mess of it, but there sure are a lot where professional just means they make a living of it.

Securing by inducing friction is a lower yield operation, except if the coeffecient of friction is >1, for example steel on rubber.
And even then it still is vastly inferior to a tie at a 180 degree angle to the force.

A 1000 pound steel block on steel floor will have a friction of 740 pound.
Tie it down with a strap giving it 3000 pound force will make the friction go up to 2960 pound.

The same block of steel tied at 180 degree will have 740 pound friction and will be held by an extra 3000 pound working against the direction of force.
So it will be held in place by a stronger force.

And now introduce some slack in the tie, so much that no real force is administered.

Asume the force working on the block rises above 740 pound.
The tied down block will start sliding and will not stop untill the external force has gone down considerably.
The tie down has no self tensioning ability.
The 180 degree tied block will start sliding but will immediately be stopped by the tie, that does have selftensioning ability.
 
...and let's be sure to compensate for the Earth's rotation, and inverse if South of the equator.
 
Good article Jo. Sure glad I don't. Have a basement. Was the traffic picture on 64 in wva ?
Thanks ron
 
The pic was taken just east of Wheeling on I-70 E, pretty much middle of nowhere.
By the time I reached the accident that caused the traffic jam, the hazmat crew was hard at work cleaning up and the crashed vehicles where gone.
Added about 40 minutes to a 3 hour trip.
 
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