I do not see where the quality of the steel in these parts is mentioned.
I'd never consider aluminum, tube or solid.
I'd go with solid steel rather than tubular steel parts.

 

It goes onto planes as well.

 

They've been absolutely perfect and completely silent. Of coarse when I installed them I used a liberal amount of an underwater lube called Aqua Shield made by D.A. Stuart, which is primarily used on boat trailer wheel bearings, as extra protection. Haven't had to make any adjustments. Everything is still good and tight.

 

At least those parts are tested for strength...Tractor Supply I doubt they care.... Most of the plane parts my son sells to the crop dusting industry doesn't come from China. Mostly European countries. Spain, Poland, Germany, etc... His company home office is in Spain and most of the planes come from Poland...can't say about airliners...but the crop dusters don't want Chinese parts... bottom line, if you are going to depend on it in a triple figure curve, I would want to know it's strength...

 

With a Tensile Strength (PSI) of 80,000, a Yield Strength (PSI) of 70,000 and a Rockwell Hardness of B80, DOM is more then strong enough and comparable to solid steel. Plus it weighs less and makes for stronger threads.

Only Chromoly is stronger then DOM, and much more expensive.

 

Not that I am any kind of engineer, but I would figure this would work for the car application... don't think any car, stock or race, is going to put these parts to the test...I stand to be corrected...

 

You have not heard of phony parts being supplied to airlines and even the Air Force? Sold by reputable companies who were duped in some cases.

 

I think you skipped the metallurgy class too often.
DOM is made from low carbon steel, basically a good mild steel, SAE 1020, 1025. It work hardens to a greater and lesser degrees and is not really heat treatable except by case hardening as the carbon content is too low. It has the benefit of being reasonably malleable for swagging and forming etc because it does not work harden too much depending on the alloy.
How you could call this stronger than solid steel is strange. As steel goes this is cheap to buy and easy to machine but not the easiest.

 

Didn't need to skip any classes; worked machine shop for 25 yrs. DOM tensile strength is at the top range of solid low carbon steels. For example, A36 tops @ 78,000 but only shows half the yield strength of DOM (37,000 vs 70,000). Often replaced stainless thick wall with DOM for High Pressure Hydraulics because of burst resisitance and cost (namely TuffDOM 620: Tensile 100,00, Yield 90,000). Thick wall DOM was harder to bend than same size solid round stock. And DOM "IS" harder to machine then solid A36. You need to work with the stuff to know the difference, so yes, I stand by my statement.

 

Please explain your common usage of the word solid, it is confusing.
eg. Thick wall DOM was harder to bend than same size solid round stock. Same size solid what? It makes a difference what the material is, see my point?
DOM steels can be many grades, low carbon and alloy. So the DOM used on these tubes could be anything from low carbon to your TuffDOM, you see where I am coming from and that is my argument in the first post, it all depends on the steel.

 

I totally agree with you. There are over 3,500 different grades of steel, encompassing unique physical, chemical and environmental properties. The solid I was referring to was the common A36 we use on a daily basis. And I agree that it all depends on the steel. Example: I put a 1/2" solid rod of A36 into a hydraulic break and bend it quite easily. The same 1/2" DOM tube will take more pressure to bend, even with the hollow space inside. Try to bend the same 1/2" solid rod of tool steel and it will snap.

All I was stating was that the DOM is adequate and comparable to using solid steel, but no one uses solid steel because of weight, when a tube can get the same results. Even a low grade carbon when cold drawn will gain much more strength from compacting the grains. Same can be said with aluminum. I've cold drawn and annealed aluminum tube to a hardness comparable to the same wall thickness of SS tubing, all in the name of weight and cost savings.

The DOM used on the Allstar Performance tubes I used have been tested on the Modified Dirt and World Of Outlaw racers with great success. And that is some kind of abuse for suspensions.