91–100 of 147 posts
They do Item and Bosch-Rexroth compatible extrusions for a reasonable price. I'd probably go with Item because the official BR stuff is a rip off and sooner or later you might want to buy "official" parts.
I want this, but I don't want to pay much more than the raw aluminium cost. The cost of pushing aluminium through an extrusion die is nearly zero. The die cost isn't much anymore in the world of cheap CNC machining. And the R&D costs for coming up with the shape shouldn't be high (and already paid off years ago). So why is that stuff still so expensive??
Wonder if there's patent protection on the US sale of that profile?
You still have to cut it, ship it, distribute it, sell it. If you were buying 500 kg, you too could probably find a way to get it cheaply made.
As a counterexample, I will say:
The cost of typing characters on a keyboard is nearly zero. So why is software still so expensive??
Earlier quoted context omitted.
Depends on the job. Cutting unistrut is far more challenging than 80/20, it weighs a lot, and the connectors are expensive because they are engineered to bear significant loads. 80/20 is a little pricier per foot but it is much, much easier to work with for applications that don't need to withstand a nuclear strike.
Not sure if the throat is large enough but a portable electric bandsaw would be able to chew through the unistrut steel and in the jobs I've used them on they are precise enough.
I want this, but I don't want to pay much more than the raw aluminium cost. The cost of pushing aluminium through an extrusion die is nearly zero. The die cost isn't much anymore in the world of cheap CNC machining. And the R&D costs for coming up with the shape shouldn't be high (and already paid off years ago). So why is that stuff still so expensive??
You used to be able to buy a basic extrusion die in China for $500 and off to the races at $0.80/lbs extrusion cost with 500kg MOQ. Wonder if there's patent protection on the US sale of that profile? You still have to cut it, ship it, distribute it, sell it. If you were buying 500 kg, you too could probably find a way to get it cheaply made. As a counterexample, I will say: The cost of typing characters on a keyboard…
Anybody into sim racing will be intimately familiar with this system. Very strong, very versatile.
If 80/20 is new to you, then you might also be unfamiliar with its steel channeled cousin, Unistrut. https://www.unistrut.us/ Unistrut is used extensively in the US to build support structures for electrical switchgear and process equipment. You can get grades suitable for outdoor and corrosives exposure. Unistrut is the Kleenex term, there are a number of work-alike / fit-alike systems. Then for round tube, there is…
I want this, but I don't want to pay much more than the raw aluminium cost. The cost of pushing aluminium through an extrusion die is nearly zero. The die cost isn't much anymore in the world of cheap CNC machining. And the R&D costs for coming up with the shape shouldn't be high (and already paid off years ago). So why is that stuff still so expensive??
You used to be able to buy a basic extrusion die in China for $500 and off to the races at $0.80/lbs extrusion cost with 500kg MOQ. Wonder if there's patent protection on the US sale of that profile? You still have to cut it, ship it, distribute it, sell it. If you were buying 500 kg, you too could probably find a way to get it cheaply made. As a counterexample, I will say: The cost of typing characters on a keyboard…
I wonder if just nobody noticed?
If 80/20 is new to you, then you might also be unfamiliar with its steel channeled cousin, Unistrut. https://www.unistrut.us/ Unistrut is used extensively in the US to build support structures for electrical switchgear and process equipment. You can get grades suitable for outdoor and corrosives exposure. Unistrut is the Kleenex term, there are a number of work-alike / fit-alike systems. Then for round tube, there is…
Earlier quoted context omitted.
For lighter duty, there is maker pipe: https://makerpipe.com/ . it's nice because the bulk of the system is electrical conduit, which I think is one of the cheapest type of beam/tube available.
> electrical conduit, which I think is one of the cheapest type of beam/tube available. There have been pretty serious PVC conduit shortages for the last year or two. In construction projects I've worked on, they've had to uprate to (much more expensive) fibreglass conduit as PVC was simply not available.