3 ms·

I don't see the advantages to this over lost-PLA casting. Am I missing something?

Animats 9y ago
That's what I was wondering. Shapeways makes metal parts by a similar process as a service. See their 2009 video.[1] There's a mini-industry making metal jewelry that way. I notice that Desktop Metal doesn't show their oven in the video. That's the big, expensive, somewhat hazardous unit. "Easily swappable aluminum gas canisters ... safe to use on the shop floor" says the data sheet.[2] Wazer, the low-end water jet cutter that's still stuck at "pre-order", has a similar problem. They're trying to make a somewhat messy industrial process less messy. There's some hand-waving involved. You end up with a sludge that's a mixture of water, shattered garnet, and whatever you're cutting. They gloss over what you have to do to dispose of that. [1] https://www.youtube.com/watch?v=B9VOwqtOglg https://www.youtube.com/watch?v=B9VOwqtOglg [2] https://desktopmetal.s3.amazonaws.com/Studio-office_friendly.pdf https://desktopmetal.s3.amazonaws.com/Studio-office_friendly...
- ortusdux 9y ago
  I was pricing out metal casting after I watched this video: https://www.youtube.com/watch?v=a-FHY5FNsWc https://www.youtube.com/watch?v=a-FHY5FNsWc 12 minutes uncut. They go from printed model to working cast piece. All new, Kaya Cast vac chamber they use is $1k, the Paragon kiln is $800, and the Electro-melt furnace is $350. Add in safety gear and incidentals and you are looking at 3-4 thousand dollars to go from a 3d print to a cast metal piece. Heck, depending on the complexity, the vac may be optional.
  - Animats 9y ago
    Hot metal casting on a small scale isn't complicated or expensive, just messy. Desktop Metal is trying to do this in an office environment. Because nobody has a shop any more. (The "maker movement" may have run its course. TechShop seems to be in financial trouble.[1]) [1] https://www.bogleheads.org/forum/viewtopic.php?t=177391 https://www.bogleheads.org/forum/viewtopic.php?t=177391
hwillis 9y ago
Expertise and materials. Casting aluminum is easy, but not very useful. Doing this yourself you can't guarantee grain structure/size, inclusions/porosity, or temper. Plus it's usually plenty easy to mill from billet since aluminum is so soft. Gold/silver is also relatively easy. You need better equipment since the temperatures are 2x higher. Strength isn't important, so casting stuff in gold/silver is quite common. Outside of jewelry there is basically no need for it. Casting something more complex like good steels, or platinum, or nickel alloys- casting will be very difficult. Molds aren't so trivial, you need preheats, and a mistake leads to liquid metal on the floor or an explosion. Sintering can be used with challenging alloys and requires almost no expertise. Everything comes certified and gets heat treated in the oven. If your time is valuable enough to warrant a metal 3d printer, it's valuable enough to make learning an entire discipline too expensive.
- taneq 9y ago
  For $360k you could just hire a materials scientist for three years, and give them $20k/year to play with.
  - fest 9y ago
    With product development times of 6-12 months, it doesn't make sense to pay 360k to get results in 3 years if you can pay 360k and get results in few months.

That's what I was wondering. Shapeways makes metal parts by a similar process as a service. See their 2009 video.[1] There's a mini-industry making metal jewelry that way. I notice that Desktop Metal doesn't show their oven in the video. That's the big, expensive, somewhat hazardous unit. "Easily swappable aluminum gas canisters ... safe to use on the shop floor" says the data sheet.[2] Wazer, the low-end water jet cutter that's still stuck at "pre-order", has a similar problem. They're trying to make a somewhat messy industrial process less messy. There's some hand-waving involved. You end up with a sludge that's a mixture of water, shattered garnet, and whatever you're cutting. They gloss over what you have to do to dispose of that. [1] https://www.youtube.com/watch?v=B9VOwqtOglg https://www.youtube.com/watch?v=B9VOwqtOglg [2] https://desktopmetal.s3.amazonaws.com/Studio-office_friendly.pdf https://desktopmetal.s3.amazonaws.com/Studio-office_friendly...

ortusdux 9y ago
I was pricing out metal casting after I watched this video: https://www.youtube.com/watch?v=a-FHY5FNsWc https://www.youtube.com/watch?v=a-FHY5FNsWc 12 minutes uncut. They go from printed model to working cast piece. All new, Kaya Cast vac chamber they use is $1k, the Paragon kiln is $800, and the Electro-melt furnace is $350. Add in safety gear and incidentals and you are looking at 3-4 thousand dollars to go from a 3d print to a cast metal piece. Heck, depending on the complexity, the vac may be optional.
- Animats 9y ago
  Hot metal casting on a small scale isn't complicated or expensive, just messy. Desktop Metal is trying to do this in an office environment. Because nobody has a shop any more. (The "maker movement" may have run its course. TechShop seems to be in financial trouble.[1]) [1] https://www.bogleheads.org/forum/viewtopic.php?t=177391 https://www.bogleheads.org/forum/viewtopic.php?t=177391

hwillis 9y ago

Expertise and materials. Casting aluminum is easy, but not very useful. Doing this yourself you can't guarantee grain structure/size, inclusions/porosity, or temper. Plus it's usually plenty easy to mill from billet since aluminum is so soft. Gold/silver is also relatively easy. You need better equipment since the temperatures are 2x higher. Strength isn't important, so casting stuff in gold/silver is quite common. Outside of jewelry there is basically no need for it. Casting something more complex like good steels, or platinum, or nickel alloys- casting will be very difficult. Molds aren't so trivial, you need preheats, and a mistake leads to liquid metal on the floor or an explosion. Sintering can be used with challenging alloys and requires almost no expertise. Everything comes certified and gets heat treated in the oven. If your time is valuable enough to warrant a metal 3d printer, it's valuable enough to make learning an entire discipline too expensive.

taneq 9y ago
For $360k you could just hire a materials scientist for three years, and give them $20k/year to play with.
- fest 9y ago
  With product development times of 6-12 months, it doesn't make sense to pay 360k to get results in 3 years if you can pay 360k and get results in few months.