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Can I take a moment to express my appreciation for products encased in aluminum extrusions? Why aren't more products like that today?

bongodongobob 3y ago
It requires custom machining rather than injecting plastic into whatever kind of molds you have.
- nsxwolf 3y ago
  But it seems simpler in some ways than injection molding. You make a single die that's a 2D cross section, extrude as much aluminum as you want, cut it into pieces.
  - 0_____0 3y ago
    I think it's just the reverse of this. It's easier than ever to get custom injection molding done, even at relatively low scales. Yes, the setup cost for machining holes in extrusion is very low, but if you're going to make even 1,000 of something you might consider getting a low volume tool made.
  - formerly_proven 3y ago
    Extruded aluminium cases are fairly popular for smaller production runs because they're generally off-the-shelf with only the faceplates being custom (usually laser cut and engraved). So the fixed costs are basically zero but the unit costs are somewhat high (aluminium is expensive). Lots of stuff is just made in large enough runs that molded parts become cheaper overall (very nonzero fixed costs but very low unit costs).
  - bluGill 3y ago
    If you only need one than the cheapest is find a local machinest and say "make a case to fit" It will be all manual and designed on the mill/lathe except where experience says "better draw this part up first" (one in a while they will scrap a part because it doesn't fit, but overall still cheap). If you need 5-100 then draw it up in CAD and have a machinist (need not be local) throw it on their CNC machines. If you need 1000 or more then design an injection process. Where I put exact numbers that is because the overhead vs efficiency of the process makes this best, where I didn't put anything it is a judgement call, it isn't clear when exactly ones process should be abandoned for the next. (even then sometimes I'm wrong, but for discussion I'm close enough - if you are doing real world work consult a real manufacturing engineer) Injection molding is great for making a lot of parts, but the cost of designing a working mold means the upfront costs are a lot higher and if you cannot reuse that mold enough to spread that cost across many parts it isn't worth doing.
- zokier 3y ago
  Not sure what you mean, extrusions are by definition produced by extruding, not machining. The die needs to be machined somehow, but so do injection molds too; neither is more or less custom?
  - bongodongobob 3y ago
    More steps to extruding using multiple steps. With molds, you stick the mold onto the nozzle and you're done. Just think about building a workbench if you were going to build it out of wood vs a mold. More screws parts and steps.
myself248 3y ago
I wish I could get a good face-on view (scan?) with dimensions, of that old extrusion. It'd be fun to 3d-print a clone; of course it won't look the same but it would get some stuff in the right approximate shape. Guess I should probably buy one, cad it up, and sell it again.
- marssaxman 3y ago
  If it's just that classic style you are looking for, and not the exact Hayes design, you might find interesting options from Protocase, Metcase, Bud, or one of the others: https://www.protocase.com/products/electronic-enclosures/aluminum.php https://www.protocase.com/products/electronic-enclosures/alu... https://www.metcaseusa.com/en/Enclosures/Aluminum-Enclosures.htm https://www.metcaseusa.com/en/Enclosures/Aluminum-Enclosures... https://www.budind.com/series/general-use-boxes/ext-series-extruded-aluminum-enclosures/#group=series-products&external_dimensions_group=0&internal_dimensions=0 https://www.budind.com/series/general-use-boxes/ext-series-e...
bluGill 3y ago
FCC rules around radio emissions used to be tougher, so aluminum was popular in early home computers. I'm not sure exactly when the rules changed, but seems like sometime in the last 1970s or early 1980s. then it took time for manufactures to realize plastic was enough cheaper as to be worth learning how to do.
- dylan604 3y ago
  At the time CPUs hit the 1GHz speeds, there were all sorts of discussions on the shielding so we don't start radiating ourselves. The internet is a fun place, facts be damned!
devwastaken 3y ago
Aluminum extrusion requires that the PCB fit into the slots. Large PCBs are expensive to prototype and most of the space isn't necessary anymore. Also the enclosures are quite costly in comparison to plastic, and most aluminum enclosures don't provide any meaningful benefit other than EMI shielding (when grounded). They don't even act as a heatsink unless you go outside the generally expected methods. However at that point it's usually easier to throw on a heatsink and have ventilation holes. But yes I do love aluminum extruded chassis.
bsder 3y ago
Everything has wireless and metal interferes with it.
rasz 3y ago
We quickly learned how to do proper emf testing and design out leakage. From 1979 Atari 800 ~3kg of alloy extrusion we got to 1982 Commodore 64 with thin metal plate followed by ~1986 models using aluminum sticker rf shield, and that was all with only the most rudimentary engineering work. Nowadays you find source of radiation leakage and filter it out right there on the pcb before it becomes a problem.
ChuckMcM 3y ago
It is a nice aesthetic right? The short answer is that in volume, injection molding is cheaper. That said, you can buy a wide variety of "standard" extrusion products if you want to build a custom case for something. This happens fairly regularly in custom instrumentation. Most recent example I saw as a tranceiver that used 80/20 quarter round extrusion (#1517) on the corners and sheet aluminum for the sides top/bottom. The front was likely laser cut or milled aluminum. I don't think it's been opened up yet for service so I don't know if there were any additional structural supports inside.

bongodongobob 3y ago

It requires custom machining rather than injecting plastic into whatever kind of molds you have.

nsxwolf 3y ago
But it seems simpler in some ways than injection molding. You make a single die that's a 2D cross section, extrude as much aluminum as you want, cut it into pieces.
- 0_____0 3y ago
  I think it's just the reverse of this. It's easier than ever to get custom injection molding done, even at relatively low scales. Yes, the setup cost for machining holes in extrusion is very low, but if you're going to make even 1,000 of something you might consider getting a low volume tool made.
- formerly_proven 3y ago
  Extruded aluminium cases are fairly popular for smaller production runs because they're generally off-the-shelf with only the faceplates being custom (usually laser cut and engraved). So the fixed costs are basically zero but the unit costs are somewhat high (aluminium is expensive). Lots of stuff is just made in large enough runs that molded parts become cheaper overall (very nonzero fixed costs but very low unit costs).
- bluGill 3y ago
  If you only need one than the cheapest is find a local machinest and say "make a case to fit" It will be all manual and designed on the mill/lathe except where experience says "better draw this part up first" (one in a while they will scrap a part because it doesn't fit, but overall still cheap). If you need 5-100 then draw it up in CAD and have a machinist (need not be local) throw it on their CNC machines. If you need 1000 or more then design an injection process. Where I put exact numbers that is because the overhead vs efficiency of the process makes this best, where I didn't put anything it is a judgement call, it isn't clear when exactly ones process should be abandoned for the next. (even then sometimes I'm wrong, but for discussion I'm close enough - if you are doing real world work consult a real manufacturing engineer) Injection molding is great for making a lot of parts, but the cost of designing a working mold means the upfront costs are a lot higher and if you cannot reuse that mold enough to spread that cost across many parts it isn't worth doing.
zokier 3y ago
Not sure what you mean, extrusions are by definition produced by extruding, not machining. The die needs to be machined somehow, but so do injection molds too; neither is more or less custom?
- bongodongobob 3y ago
  More steps to extruding using multiple steps. With molds, you stick the mold onto the nozzle and you're done. Just think about building a workbench if you were going to build it out of wood vs a mold. More screws parts and steps.

myself248 3y ago

I wish I could get a good face-on view (scan?) with dimensions, of that old extrusion. It'd be fun to 3d-print a clone; of course it won't look the same but it would get some stuff in the right approximate shape. Guess I should probably buy one, cad it up, and sell it again.

marssaxman 3y ago
If it's just that classic style you are looking for, and not the exact Hayes design, you might find interesting options from Protocase, Metcase, Bud, or one of the others: https://www.protocase.com/products/electronic-enclosures/aluminum.php https://www.protocase.com/products/electronic-enclosures/alu... https://www.metcaseusa.com/en/Enclosures/Aluminum-Enclosures.htm https://www.metcaseusa.com/en/Enclosures/Aluminum-Enclosures... https://www.budind.com/series/general-use-boxes/ext-series-extruded-aluminum-enclosures/#group=series-products&external_dimensions_group=0&internal_dimensions=0 https://www.budind.com/series/general-use-boxes/ext-series-e...

bluGill 3y ago

FCC rules around radio emissions used to be tougher, so aluminum was popular in early home computers. I'm not sure exactly when the rules changed, but seems like sometime in the last 1970s or early 1980s. then it took time for manufactures to realize plastic was enough cheaper as to be worth learning how to do.

dylan604 3y ago
At the time CPUs hit the 1GHz speeds, there were all sorts of discussions on the shielding so we don't start radiating ourselves. The internet is a fun place, facts be damned!

devwastaken 3y ago

Aluminum extrusion requires that the PCB fit into the slots. Large PCBs are expensive to prototype and most of the space isn't necessary anymore. Also the enclosures are quite costly in comparison to plastic, and most aluminum enclosures don't provide any meaningful benefit other than EMI shielding (when grounded). They don't even act as a heatsink unless you go outside the generally expected methods. However at that point it's usually easier to throw on a heatsink and have ventilation holes. But yes I do love aluminum extruded chassis.

bsder 3y ago

Everything has wireless and metal interferes with it.

rasz 3y ago

We quickly learned how to do proper emf testing and design out leakage. From 1979 Atari 800 ~3kg of alloy extrusion we got to 1982 Commodore 64 with thin metal plate followed by ~1986 models using aluminum sticker rf shield, and that was all with only the most rudimentary engineering work. Nowadays you find source of radiation leakage and filter it out right there on the pcb before it becomes a problem.

ChuckMcM 3y ago

It is a nice aesthetic right? The short answer is that in volume, injection molding is cheaper. That said, you can buy a wide variety of "standard" extrusion products if you want to build a custom case for something. This happens fairly regularly in custom instrumentation. Most recent example I saw as a tranceiver that used 80/20 quarter round extrusion (#1517) on the corners and sheet aluminum for the sides top/bottom. The front was likely laser cut or milled aluminum. I don't think it's been opened up yet for service so I don't know if there were any additional structural supports inside.