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User: Rei

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  1. Re:What Happens When 3D Printers Get Better??? on DOJ Reaches Settlement On Publication of Files About 3D Printed Firearms (joshblackman.com) · · Score: 1

    Honestly, though, I really don't understand why guns seem to be the number one thing people obsess over printing. At least be creative.

    There's one 3d printing project which has been tempting me recently... trying to make the first 3d printed telescope mirrors (stiffened on the back with a 3d truss structure). Now obviously you can't get anywhere near the required precision from today's printers. For example, on iMaterialise, the best resolution in metal is ~100 micron, and in plastic ~200-250 micron. So 2-3 orders of magnitude too coarse. But I was thinking it could be great for 3d printing a scaffolding for a liquid mirror. Not so much a liquid mirror in the traditional approach where you have a reflective liquid and use that directly as a mirror, but rather having the liquid as a polymer highly diluted with solvent, and very slowly evaporating the solvent off while spinning the mirror at the proper speed, so that the deposited polymer smooths out the unevenness. Then sending it off to be silvered.

    Dunno how well it'd work; I suspect something would go awry. Maybe multiple independent roadblocks ;) But it'd still be fun to try. The main things that keep me from trying it are A) other projects, B) I really have no need for a new telescope ;)

  2. Re:What Happens When 3D Printers Get Better??? on DOJ Reaches Settlement On Publication of Files About 3D Printed Firearms (joshblackman.com) · · Score: 1

    You can always order parts from online services. Then you get actual quality parts, from quality printers, run by people who know what the heck they're doing.

    Of course, if you're trying to order gun parts, you're limited by how effectively the company can recognize what you're printing as gun parts.

  3. Re: When all you have is a hammer on Giant Tesla Battery Project Now Proposed For Silicon Valley (digitaltrends.com) · · Score: 4, Interesting

    That is the official rated lifespan for Tesla's grid products. Accelerated lifecycle testing is not a new concept. It's also worth noting that degradation in Tesla's vehicle batteries has been very, very low. Early model-year Model S taxis with several hundred thousand kilometers on them still show over 90% capacity retention. And the grid products use a longer cycle life chemistry.

  4. Re:Tesla or Panasonic batteries? on Giant Tesla Battery Project Now Proposed For Silicon Valley (digitaltrends.com) · · Score: 1

    You described the arrangement of Tesla's purchase of 18650-format cells for the Model S and X. The model 3 uses 2170 format cells manufactured in GF1. Ownership and management of the plant is jointly held.

  5. Re:Tesla or Panasonic batteries? on Giant Tesla Battery Project Now Proposed For Silicon Valley (digitaltrends.com) · · Score: 1

    This isn't exactly correct. Your description of the arrangement is accurate for the 18650 cells, but not the 2170s.

  6. Re:Tesla or Panasonic batteries? on Giant Tesla Battery Project Now Proposed For Silicon Valley (digitaltrends.com) · · Score: 1

    No - this has never been asked on any of the conference calls. One presumes that all Gigafactory IP is jointly owned, since GF1 is jointly owned.

  7. Re: When all you have is a hammer on Giant Tesla Battery Project Now Proposed For Silicon Valley (digitaltrends.com) · · Score: 2, Informative

    1) The normal lifespan of the batteries is 15 years, not 3-5.

    2) Consumer lithium ion batteries usually aren't recycled because they're tiny things that are more trouble than they're worth. EV and grid storage battery packs most definitely are recycled. For obvious reasons, because people want the large amounts of nickel, cobalt and lithium therein back. Right now Tesla's batteries are recycled by third party contractors, although eventually they want to incorporate the recycling process directly into their Gigafactories as a feedstock.

    3) They do not have any unusual level of toxicity. The cathodes are in the form of inert metal oxides. The anodes are graphite. I cannot comment on the electrolyte as I don't know which one they're using - probably boron trifluoride or lithium hexafluoride. They decompose in nature to simple fluorine compounds. High levels of exposure to these can cause fluorosis, but there's no way you're going to consume more fluoride from "leaked batteries" (as if people were just stockpiling them, see #2) vs. from water fluoridation. As for lithium itself, we should probably be consuming more, not less (and again, see #2).

  8. Re:Tesla or Panasonic batteries? on Giant Tesla Battery Project Now Proposed For Silicon Valley (digitaltrends.com) · · Score: 4, Informative

    The Powerpacks use Tesla's new 2170-format cells produced at the Gigafactory, which is a Tesla-Panasonic joint venture.

  9. Re:What do the fuel cells have to do with Tesla? on Giant Tesla Battery Project Now Proposed For Silicon Valley (digitaltrends.com) · · Score: 1

    Back to the GP: were you confusing the fuel cell project with the Powerpack project? It's a completely different project. The Slashdot summary did not in any way suggest that Tesla was involved. It was introduced with words "And speaking of power sources", not "And speaking of Tesla batteries".

  10. Re:What do the fuel cells have to do with Tesla? on Giant Tesla Battery Project Now Proposed For Silicon Valley (digitaltrends.com) · · Score: 1

    It's literally in the headline:

    PG&E applies to build Tesla’s largest battery farm yet in Silicon Valley

    Tesla’s largest-ever Powerpack installation may be coming to Northern California. Pacific Gas and Electric Company (PG&E) applied to the California Public Utilities Commission (CPUC) for approval for a utility-owned 182.5 MW energy storage farm using Tesla Powerpacks at the company’s energy storage site in Moss Landing.

    But as an aside, can we for once have an article about electricity that doesn't mix up power and energy?

    Power: The peak output is 182,5MW
    Energy: The base proposal is for four hours at 182,5 MW, or 730 MWh. The optional expansion is to six hours at 182,5 MW, or 1,1 GWh.

  11. Huh?

  12. Re:Your own garage only or random parking anywhere on Tesla Model 3 Now Offers 'Summon' Self-Parking Feature (autoblog.com) · · Score: 2

    If this requires the parking spot to be a well defined position programmed in advance

    It doesn't. It's situation-adaptive, making use of the ultrasonic sensors

    It's not perfect, though. It's slow, and when there's uncertainty it prefers to give up rather than risk hitting something (particularly noteworthy in really tight situations, where you want summon the most). And there have been some rare instances where things have been hit, although it's not common. For most people, it's just a party trick. But it does occasionally come in handy, for things like the "car parked in a puddle" situation and the like. It's not yet to the point of "drop you off at the door and then go find a parking space", and it's not clear when, if ever, it will be (self-driving optimists would say "soon"; I'm not among them). But some more speed and reliability would make summon (and autoparking) see significantly more use.

  13. Re:Works 99 times out of 100 on Tesla Model 3 Now Offers 'Summon' Self-Parking Feature (autoblog.com) · · Score: 4, Funny

    Yeah, but that easter egg that they added to make the car scream "OH YEAAHH!" when it does so makes it totally worth it ;)

  14. Re:Scary on Tesla Model 3 Now Offers 'Summon' Self-Parking Feature (autoblog.com) · · Score: 3, Informative

    What happens in the event of a computer or actuator malfunction?

    The control unit has onboard redundancy. There are redundant actuators controlling all safety-related driving functions. You can see the layout here.

    Re, crashing: anything that deploys the airbags also deploys the pyro fuse in the battery pack. All HV power is instantaneously cut. No driving.

    What's to prevent a thief / hijacker from opening the doors and driving off? Um, the locks? The fact that touching the door handles, steering wheel, accelerator, or pretty much anything else disables Summon? The fact that (assuming we're talking about the Model 3) you have to have a paired phone or the card in the car to drive it?

  15. Re:How about SCUBA and a winch? on Elon Musk's Team Is Talking With Thai Officials for Cave Rescue (bloomberg.com) · · Score: 1

    Sounds like the vast majority of those problems could be eliminated by, for each kid, giving them enough valium-or-equivalent to dope a horse, and having the professional divers haul them out while they trip their brains out. Is there anything that they personally must take responsibility for, that a professional diver with them couldn't do for them (buoyancy, air supply monitoring, etc) with the right kit?

  16. Nor were they supposed to be making profits right now.

    They're supposed to be profitable in Q3. Come back here then if they're not.

  17. Re:Woah! calm it down there on Elon Musk's Team Is Talking With Thai Officials for Cave Rescue (bloomberg.com) · · Score: 2

    Specifically, what was offered was ground-penetrating radar they've been developing with Boring Company and an airdropped crate of powerpacks and high-powered pumps.

    But it wasn't Musk who started this conversation. Someone asked him on Twitter, and his initial response was that he would if he could but he didn't know exactly how he could be of help, and that he presumes that the Thai authorities are on top of the situation.

  18. Re:And ... if they hadn't? on Tesla Meets Self-Imposed Deadline For Model 3, Rolls Out 7,000 Cars In a Week (cnbc.com) · · Score: 1

    By the way - since you apparently care so much about me, by all means feel free to do the legwork for me on whether options purchases of US stocks are possible in Iceland, through whom, and what the fee schedule is.

  19. Re:And ... if they hadn't? on Tesla Meets Self-Imposed Deadline For Model 3, Rolls Out 7,000 Cars In a Week (cnbc.com) · · Score: 1

    Not really,

    Yes, really. Margins, both GAAP and non-GAAP, continue rising. SG&A remains steady, while volumes keep climbing.

    And guess what? SG&A will be falling in Q3 due to the layoffs. And Tesla is transitioning the supercharger network from a subsidy to an entity that pays for its own expansion, something that was too small of an effect to be visible in Q1, will be small but meaningful in Q2, and increasingly huge from Q3 onward. Meanwhile, Tesla Energy (Powerwall, Powerpacks, solar roofing products) are all scheduled to undergo massive growth in Q4 (small in Q3, insignificant in Q2). Tesla for example just announced a Powerpack project nearly an order of magnitude larger than the largest they've ever built.

    Yep, I did. Promise: 6000 vehicles a week. Result: 2000 vehicles a week.

    You do realize that even if you're dumb enough to view a target of achieving a 6k/wk rate in order to achieve a goal of a 5k/wk rate by the end of the quarter as meaning "we plan to produce 6k per week every week this quarter", the average person is not that stupid, don't you?

  20. Re:Ah no. The shorts are fine. on Tesla Meets Self-Imposed Deadline For Model 3, Rolls Out 7,000 Cars In a Week (cnbc.com) · · Score: 1

    They had $2.8B of cash on hand

    Yes, that's known as a "several billion dollar buffer".

    after net negative cash flows of $800M

    1) $675M

    2) That's an entire year's worth. The concept that they can't become profitable in a year at the current high burn rate - let alone a declining rate - is utter nonsense.

    3) Capex creates assets that can be borrowed against.

    and have unquestionably burnt a lot more this quarter.

    Have unquestionably not.

  21. Re:And ... if they hadn't? on Tesla Meets Self-Imposed Deadline For Model 3, Rolls Out 7,000 Cars In a Week (cnbc.com) · · Score: 1

    What the heck are you talking about? I bought shares previously because that was the simplest thing for me. Even that is hard enough here (non-US), and I'm stuck paying 1% transaction fees - you all are lucky that you can trade US stocks for flat fees or in some cases free. As for options, I mean exactly what I said: "I may well". I simply haven't looked into them yet, whether it's even possible for me to get them. I've only been in the market for a matter of months.

  22. Re:And ... if they hadn't? on Tesla Meets Self-Imposed Deadline For Model 3, Rolls Out 7,000 Cars In a Week (cnbc.com) · · Score: 1

    This stock has significantly underperformed the market this year

    The monthly running average from a year ago is well lower than the current monthly running average. And of course you picked endpoints that would try to support your viewpoint. I could just as well pick endpoints from a couple months ago - when I bought in - and compare them to now; it's yielded a tremendous return.

    The long-term picture, however, is the most fair way to compare. And Tesla has done anything but "underperform".

    Shorts are not made "over several years", they are made over days, weeks or months.

    Their average performance is made over several years, even though individual short positions are not that long.

    The poor news announced yesterday has been a bonanza for shorters

    Not coming close to the amount that they've lost in the past several months.

  23. Re:And ... if they hadn't? on Tesla Meets Self-Imposed Deadline For Model 3, Rolls Out 7,000 Cars In a Week (cnbc.com) · · Score: 1

    I've only owned TSLA for a couple months, and I've been talking about Tesla on this site for far longer than that.

    As for options, I may well.

  24. Re:And ... if they hadn't? on Tesla Meets Self-Imposed Deadline For Model 3, Rolls Out 7,000 Cars In a Week (cnbc.com) · · Score: 1

    MANY HAVE, and they have made a fortune from this underperforming stock

    On average, they've lost their shirt on this incredibly well performing stock. Can you not even look at a stock price graph? Tesla's price has skyrocketed over the past several years, and has gone through multiple short squeezes in the process.

  25. Re:Ah no. The shorts are fine. on Tesla Meets Self-Imposed Deadline For Model 3, Rolls Out 7,000 Cars In a Week (cnbc.com) · · Score: 1

    No, we're not. Tesla has no need for debt or equities markets to survive, and a several billion dollar buffer is not "threading the needle".