4 ms·

The fricking media/PR around 3D printing is really annoying. You can't match: 1) Get benefits of strength like in forging process 2) Case hardening would sti

The fricking media/PR around 3D printing is really annoying. You can't match: 1) Get benefits of strength like in forging process 2) Case hardening would still need to be done 3) Shot peening and surface hardening? 4) Speed 5) Cost 6) Robustness and reliability, how many 3D printers have various ways of 3D printing, how do you validate parts for strength? It is a monumental challenge. Traditional processes are vetted and tested for decades. 7) Material wastage 8) Footprint and floorspace (1 injection molding machine can replace about a 10,000 3d printers to match the volume). 9) Power consumption 10) Human labor and attendance (may be this is already solved) I work in manufacturing and we have a bunch of 3d printers. They make amazing tools for prototyping and testing things out. Hell, we don't even use them anymore because its just faster and cheaper to get it from Protolabs / 3D Hubs. 3D Printing has extremely useful applications where we can optimize the shape without concerning for right angles, draft angles, chamfers, and fillets. Some of the ANSYS tools can use algorithms to optimize the shape that looks like a bio-mechanical thing because we are no longer constrained by aforementioned restrictions. But the public needs to understand that 3D printing will not replace everything. It is like saying cars replaced bicycles when they were being used in late 1890's... no, we still have bicylces 120 years later and will continue to use them. 3D printing serves a niche purpose and a huge benefit in medical/dental industries but boy the media is doing a horrible job of explaining its advantages and disadvantages. I just see misinformation all over.

wil421 6y ago
In my experience it’s not the general public who is hyping 3D printing its the tech/nerd crowd. I can remember when 3D printing was getting affordable and people telling me I just didn’t understand how it would change manufacturing.
- deleted 6y ago
  [deleted]
ReactiveJelly 6y ago
> It is like saying cars replaced bicycles when they were being used in late 1890's... no, we still have bicycles A couple years ago, maybe on HN itself, someone bragged about how QR codes were totally obsolete because they had made a better version. Their 'better' version relied on a web service that they controlled. So, I can't scan the code offline, and I'm at their mercy. It would have been a great joke if they weren't so serious.
- pankajdoharey 6y ago
  Thats an Interesting story, Source please?
scarier 6y ago
To be fair, aluminum isn't typically case-hardened, at least for this application. While I lament the loss of the strength benefits from forging, they may be able to make up for a lot of them by using more material around the wrist pins than on a typical forged piston. 10% weight savings is pretty compelling, as the limiting factor in engine speed is typically con-rod stress. 3D-printed metal parts are already a thing in a number of aerospace applications--I imagine the reliability piece is either fairly well-solved for sintered metal printing, or the parts are expensive enough that we're willing to print each one more than once if required.
nimbius 6y ago
Bingo. Pistons have about as much work in them as a piece of jewelry. by the time your 3d printer cranks out a part, a five stage hot press and a normalizing furnace have already shot out enough raw forged parts to make your printer an expensive paperweight. depending on the metal you can still heat-treat it, but thats a big "depending." metals for pistons and gears are an incredible trade secret. sometimes gas furnace hardening happens after shave or milling steps or even inbetween them. 3d printed parts are right up there in terms of durability with prototype parts, but miles away in terms of cost. these arent your average sintered metal molds.
HeadsUpHigh 6y ago
I was watching a project that involved making a bunch of plastic parts. The total volume was in the low thousands. It was enough parts to start thinking about the scale but not enough to make molds worth it. It seemed like the breakeven point for molds was around 20-50k parts depending on the mold. The design that was used for the final product was made super fast custom made reprap printers with rather low accuracy. Due to the unique abilities of 3d printers it ended up being very strong and durable with a honeycomb structure inside. 3d printers are at the point were for some applications it makes sense to use them in production. The exceptions are high volume as well as very low volume that has high strength requirements( and even then for metal printers some stuff can be done post-manufacturing).

wil421 6y ago

In my experience it’s not the general public who is hyping 3D printing its the tech/nerd crowd. I can remember when 3D printing was getting affordable and people telling me I just didn’t understand how it would change manufacturing.

deleted 6y ago
[deleted]

ReactiveJelly 6y ago

> It is like saying cars replaced bicycles when they were being used in late 1890's... no, we still have bicycles A couple years ago, maybe on HN itself, someone bragged about how QR codes were totally obsolete because they had made a better version. Their 'better' version relied on a web service that they controlled. So, I can't scan the code offline, and I'm at their mercy. It would have been a great joke if they weren't so serious.

pankajdoharey 6y ago
Thats an Interesting story, Source please?

scarier 6y ago

To be fair, aluminum isn't typically case-hardened, at least for this application. While I lament the loss of the strength benefits from forging, they may be able to make up for a lot of them by using more material around the wrist pins than on a typical forged piston. 10% weight savings is pretty compelling, as the limiting factor in engine speed is typically con-rod stress. 3D-printed metal parts are already a thing in a number of aerospace applications--I imagine the reliability piece is either fairly well-solved for sintered metal printing, or the parts are expensive enough that we're willing to print each one more than once if required.

nimbius 6y ago

Bingo. Pistons have about as much work in them as a piece of jewelry. by the time your 3d printer cranks out a part, a five stage hot press and a normalizing furnace have already shot out enough raw forged parts to make your printer an expensive paperweight. depending on the metal you can still heat-treat it, but thats a big "depending." metals for pistons and gears are an incredible trade secret. sometimes gas furnace hardening happens after shave or milling steps or even inbetween them. 3d printed parts are right up there in terms of durability with prototype parts, but miles away in terms of cost. these arent your average sintered metal molds.

HeadsUpHigh 6y ago

I was watching a project that involved making a bunch of plastic parts. The total volume was in the low thousands. It was enough parts to start thinking about the scale but not enough to make molds worth it. It seemed like the breakeven point for molds was around 20-50k parts depending on the mold. The design that was used for the final product was made super fast custom made reprap printers with rather low accuracy. Due to the unique abilities of 3d printers it ended up being very strong and durable with a honeycomb structure inside. 3d printers are at the point were for some applications it makes sense to use them in production. The exceptions are high volume as well as very low volume that has high strength requirements( and even then for metal printers some stuff can be done post-manufacturing).