8 ms·

I am a mechanical engineer (a machine design engineer in fact) and this press looks like would happen if you hired 30 of 23-year-old me fresh out of college, ga

by quasse 9y ago

I am a mechanical engineer (a machine design engineer in fact) and this press looks like would happen if you hired 30 of 23-year-old me fresh out of college, gave them an effectively unlimited budget and said "make me the swankiest press you can imaging". Lots of clever ideas and fancy machined parts with no thought for cost savings or whether there's an easier way to do something. 15A 330V DC motor? To squish a bag of pulp? The best things I've gotten career and skill wise from more senior engineers has been the feedback where they looked at a design and said "looks fancy, but what were you thinking?". This machine looks like it needed some more grizzled manufacturing veterans to inject some sense into the design process.

SEJeff 9y ago
How would you, given what you know now, do this better? Not saying you can't, just curious what your experience has taught you to do differently.
- jacquesm 9y ago
  How about gear it further down behind a smaller motor for starters? It's not like you're about to start wood turning, there is already a gearbox in there, with the right ratio a much smaller motor likely would suffice. That thing is so over-engineered it is almost as if it was a joke.
  - gingerbread-man 9y ago
    Apparently the press already takes ~2.5min to make a glass of juice. A smaller motor would probably take even longer
    - jacquesm 9y ago
      The competition (hand press, bottles) and so on are way ahead of them then. Maybe we can out-do them and build a hydraulic version: "Now with 50 tons of pressure". I have a hydro pack lying around here somewhere with a really neat 3" puck piston. I'm sure that would do the job just fine and maybe even a little bit quicker.
    - wiredfool 9y ago
      With a 15A, 330V motor. That's almost 5KW, or 6.6 HP, for those of you who don't use SI units.
      - freehunter 9y ago
        Which is more power than my lawn mower, which makes comparable outputs as what is inside those juice packets.
  - TD-Linux 9y ago
    I suspect the majority of the power is already burned in the gears. Two teslas is 40000 newtons. If we assume the press moves 5cm in 2.5 minutes: 40000 * (0.05/150) = 13 watts.
  - yongjik 9y ago
    I wonder if, with the right set of gears, someone could make a zero-emission, disaster-ready and eco-friendly version that says "please insert the pouch, step on the juicer and gently hop on it until the juice is ready." Hey if any VC is listening I'm willing to sell this idea. Only asking $10M.
    - jacquesm 9y ago
      Toddler powered FTW.
  - taneq 9y ago
    > That thing is so over-engineered it is almost as if it was a joke. Maybe different people use that term differently but I wouldn't call that 'over-engineered'. I'd just call it 'poorly engineered'. Mismatched components doing a poor job despite being far more expensive than necessary. If they'd put a well designed hydraulic press in there, I'd call it over-engineered. :)
  - diydsp 9y ago
    Ironically I literally can't view the page on my iPad. There's somehow too much happening for this 2013 device to handle.
    - i336_ 9y ago
      I can't go past this comment without mentioning that I'm currently using a ThinkPad T43 while my i3 box is on indefinite loan to a friend... and despite being 11 years old the T43 loads the site just fine. The video's a bit much (youtube-dl for that) but yeah. FWIW, easily 85-90% of what I try and open on my old Kindle (the super-basic version from a few years ago) makes the browser - and sometimes the whole UI - completely seize up. I'm guessing (based on how everything gets super sluggish) they didn't enable swapping - which does make total sense, but then the device only has 256MB(?) of RAM...... Now I'm curious what the iPad's virtual memory settings are like. And whether swap on Flash (of the caliber that goes in an iPad) is a good idea!
- quasse 9y ago
  Just to be clear, I don't want to claim expertise I don't have: I'm only just a bit past that stage in my career and have had a lot to learn in the past few years. Just a stream of consciousness set of notes from my reading of the article though: * The design of the interior machined parts looks like a classic case of why machinists make fun of / mildly dislike engineers. "As long as I can make it in a 3D model we can make it out of metal, right?" They're beautiful, but if a part is going to be hidden from your end user, maybe think about how much manufacturing time those artistic rounded fillets are going to take up and design something that can be run on a 3 axis machine instead of a five axis machine. * That injection molding. Wow. I'm kind of in two minds about that, because I can at least get behind the idea of spending time and money on the part of a machine your customers will be touching and seeing every day but good lord is it expensive, especially for low volume boutique products. * The gear system. I'm surprised to see a set of spur gears in there vs a planetary gear set. Planetary gears are quiet and space efficient while also being able to transmit large loads. I'm surprised there actually wasn't a gearbox manufacturer from the cordless drill industry (another high input speed -> high output torque device) that they could tap to get a already designed and mass produced gear-train for much less money.
  - Animats 9y ago
    That's about what I thought. That recessed fillet makes me think someone clicked "fillet" in Autodesk Inventor, not realizing what it does to the machining time. The machined parts seem to have machined features on all sides. I wonder how many setups that takes. If they'd designed it out of thick flat plates, the plates could be cut on a water jet or plasma cutter, or machined with one setup on a 3-axis mill. I haven't done injection molding, but I know that making the molds is the expensive part. Once you've made the molds, making parts is cheap. If there was an overoptimistic market projection, the mold cost per part would seem low. There's a fairly common arrangement for presses where a motor drives a worm gear which drives a ring gear with a threaded or ball screw hole. Here's a consumer-appliance grade version from China, used in an oil press, pasta extruder, or juicer.[1][2] $2 in quantity 500. The first thing to do in mechanical design is to find out what you can buy. [1] https://honestmotor.en.alibaba.com/product/1971456634-222573305/oil_press_DC_worm_gear_motor.html https://honestmotor.en.alibaba.com/product/1971456634-222573... [2] https://www.alibaba.com/product-detail/220v-dc-worm-gear-motor-for_60506053342.html https://www.alibaba.com/product-detail/220v-dc-worm-gear-mot...
falcolas 9y ago
I think you've also just well described so much of startup software development as well. Great ideas, a grand pool of undiluted computer science theory, nobody going "why do you need 120 servers to run a webpage?"
- jacquesm 9y ago
  > Great ideas, a grand pool of undiluted computer science theory, nobody going "why do you need 120 servers to run a webpage?" I actually untangled a mess like that (only it was some 200+ VMs on 20 fancy HP blades + SAN to serve 5000 users daily), don't even joke about it. If you arrived with something the size of a semi-trailer to squeeze some juice people would likely ask you if you're all ok in the upper department but if you do the same in computer land they call you 'architect' and promote you. So much of that complexity is hidden and your average business owners have no clue what is required and what is overkill.
  - spydum 9y ago
    The great sadness to me is that incentives in architecture almost encourage this... Hardware is cheap and good designers are few. So when guys like you can come in and squash down the complexity,, company thinks it won twice (first time for delivery.. Wow look how fast it is!; second time for efficiency)
    - jacquesm 9y ago
      I strongly suspect there was more at play there (huge kickback to one of the people ordering the hardware). And no, the customer didn't think they won twice, the first time almost killed them. For all those goodies it still did not perform. You really wonder how they managed to burn all those cycles.
  - ams6110 9y ago
    So why is it then that 23 year old engineers are building everything in SV? It certainly explains a lot about what I see happening there.
Baeocystin 9y ago
"An Engineer can do for a dime what any fool could do for a dollar." One of my favorite instructors from college.
nikanj 9y ago
Fresh out of college? Aren't dropouts all the rage nowadays? By graduation, you're ooooold, and old people only have stale ideas.
- johan_larson 9y ago
  Yeah. Young people are just smarter.
  - rak00n 9y ago
    Oh gosh. This is when Mark Zuckerberg sounded just like a more stupid and ageist version of Donald Trump.
mannykannot 9y ago
This is probably the explanation - I have certainly seen the sort of software equivalents that several other posters have written about - but I am wondering if it might have come from a military-industrial / cost-plus contracting style of development.

by quasse 9y ago

SEJeff 9y ago

How would you, given what you know now, do this better? Not saying you can't, just curious what your experience has taught you to do differently.

jacquesm 9y ago
How about gear it further down behind a smaller motor for starters? It's not like you're about to start wood turning, there is already a gearbox in there, with the right ratio a much smaller motor likely would suffice. That thing is so over-engineered it is almost as if it was a joke.
- gingerbread-man 9y ago
  Apparently the press already takes ~2.5min to make a glass of juice. A smaller motor would probably take even longer
  - jacquesm 9y ago
    The competition (hand press, bottles) and so on are way ahead of them then. Maybe we can out-do them and build a hydraulic version: "Now with 50 tons of pressure". I have a hydro pack lying around here somewhere with a really neat 3" puck piston. I'm sure that would do the job just fine and maybe even a little bit quicker.
  - wiredfool 9y ago
    With a 15A, 330V motor. That's almost 5KW, or 6.6 HP, for those of you who don't use SI units.
    - freehunter 9y ago
      Which is more power than my lawn mower, which makes comparable outputs as what is inside those juice packets.
- TD-Linux 9y ago
  I suspect the majority of the power is already burned in the gears. Two teslas is 40000 newtons. If we assume the press moves 5cm in 2.5 minutes: 40000 * (0.05/150) = 13 watts.
- yongjik 9y ago
  I wonder if, with the right set of gears, someone could make a zero-emission, disaster-ready and eco-friendly version that says "please insert the pouch, step on the juicer and gently hop on it until the juice is ready." Hey if any VC is listening I'm willing to sell this idea. Only asking $10M.
  - jacquesm 9y ago
    Toddler powered FTW.
- taneq 9y ago
  > That thing is so over-engineered it is almost as if it was a joke. Maybe different people use that term differently but I wouldn't call that 'over-engineered'. I'd just call it 'poorly engineered'. Mismatched components doing a poor job despite being far more expensive than necessary. If they'd put a well designed hydraulic press in there, I'd call it over-engineered. :)
- diydsp 9y ago
  Ironically I literally can't view the page on my iPad. There's somehow too much happening for this 2013 device to handle.
  - i336_ 9y ago
    I can't go past this comment without mentioning that I'm currently using a ThinkPad T43 while my i3 box is on indefinite loan to a friend... and despite being 11 years old the T43 loads the site just fine. The video's a bit much (youtube-dl for that) but yeah. FWIW, easily 85-90% of what I try and open on my old Kindle (the super-basic version from a few years ago) makes the browser - and sometimes the whole UI - completely seize up. I'm guessing (based on how everything gets super sluggish) they didn't enable swapping - which does make total sense, but then the device only has 256MB(?) of RAM...... Now I'm curious what the iPad's virtual memory settings are like. And whether swap on Flash (of the caliber that goes in an iPad) is a good idea!
quasse 9y ago
Just to be clear, I don't want to claim expertise I don't have: I'm only just a bit past that stage in my career and have had a lot to learn in the past few years. Just a stream of consciousness set of notes from my reading of the article though: * The design of the interior machined parts looks like a classic case of why machinists make fun of / mildly dislike engineers. "As long as I can make it in a 3D model we can make it out of metal, right?" They're beautiful, but if a part is going to be hidden from your end user, maybe think about how much manufacturing time those artistic rounded fillets are going to take up and design something that can be run on a 3 axis machine instead of a five axis machine. * That injection molding. Wow. I'm kind of in two minds about that, because I can at least get behind the idea of spending time and money on the part of a machine your customers will be touching and seeing every day but good lord is it expensive, especially for low volume boutique products. * The gear system. I'm surprised to see a set of spur gears in there vs a planetary gear set. Planetary gears are quiet and space efficient while also being able to transmit large loads. I'm surprised there actually wasn't a gearbox manufacturer from the cordless drill industry (another high input speed -> high output torque device) that they could tap to get a already designed and mass produced gear-train for much less money.
- Animats 9y ago
  That's about what I thought. That recessed fillet makes me think someone clicked "fillet" in Autodesk Inventor, not realizing what it does to the machining time. The machined parts seem to have machined features on all sides. I wonder how many setups that takes. If they'd designed it out of thick flat plates, the plates could be cut on a water jet or plasma cutter, or machined with one setup on a 3-axis mill. I haven't done injection molding, but I know that making the molds is the expensive part. Once you've made the molds, making parts is cheap. If there was an overoptimistic market projection, the mold cost per part would seem low. There's a fairly common arrangement for presses where a motor drives a worm gear which drives a ring gear with a threaded or ball screw hole. Here's a consumer-appliance grade version from China, used in an oil press, pasta extruder, or juicer.[1][2] $2 in quantity 500. The first thing to do in mechanical design is to find out what you can buy. [1] https://honestmotor.en.alibaba.com/product/1971456634-222573305/oil_press_DC_worm_gear_motor.html https://honestmotor.en.alibaba.com/product/1971456634-222573... [2] https://www.alibaba.com/product-detail/220v-dc-worm-gear-motor-for_60506053342.html https://www.alibaba.com/product-detail/220v-dc-worm-gear-mot...

falcolas 9y ago

I think you've also just well described so much of startup software development as well. Great ideas, a grand pool of undiluted computer science theory, nobody going "why do you need 120 servers to run a webpage?"

jacquesm 9y ago
> Great ideas, a grand pool of undiluted computer science theory, nobody going "why do you need 120 servers to run a webpage?" I actually untangled a mess like that (only it was some 200+ VMs on 20 fancy HP blades + SAN to serve 5000 users daily), don't even joke about it. If you arrived with something the size of a semi-trailer to squeeze some juice people would likely ask you if you're all ok in the upper department but if you do the same in computer land they call you 'architect' and promote you. So much of that complexity is hidden and your average business owners have no clue what is required and what is overkill.
- spydum 9y ago
  The great sadness to me is that incentives in architecture almost encourage this... Hardware is cheap and good designers are few. So when guys like you can come in and squash down the complexity,, company thinks it won twice (first time for delivery.. Wow look how fast it is!; second time for efficiency)
  - jacquesm 9y ago
    I strongly suspect there was more at play there (huge kickback to one of the people ordering the hardware). And no, the customer didn't think they won twice, the first time almost killed them. For all those goodies it still did not perform. You really wonder how they managed to burn all those cycles.
- ams6110 9y ago
  So why is it then that 23 year old engineers are building everything in SV? It certainly explains a lot about what I see happening there.

Baeocystin 9y ago

"An Engineer can do for a dime what any fool could do for a dollar." One of my favorite instructors from college.

nikanj 9y ago

Fresh out of college? Aren't dropouts all the rage nowadays? By graduation, you're ooooold, and old people only have stale ideas.

johan_larson 9y ago
Yeah. Young people are just smarter.
- rak00n 9y ago
  Oh gosh. This is when Mark Zuckerberg sounded just like a more stupid and ageist version of Donald Trump.

mannykannot 9y ago

This is probably the explanation - I have certainly seen the sort of software equivalents that several other posters have written about - but I am wondering if it might have come from a military-industrial / cost-plus contracting style of development.