CoffeeHit
Page 64 of 116 FirstFirst ... 145460616263646566676874114 ... LastLast
Results 631 to 640 of 1151

Thread: Decent espresso

  1. #631
    Join Date
    Apr 2016
    Location
    Hong Kong
    Posts
    465
    Post Thanks / Like
    Mentioned
    18 Post(s)

    Default

    Our knockbox design came in today, 50% larger than the last one, CNCed from two blocks of aluminum and then welded together. It's a bit of a Frankenstein, but it's useful for judging relative size and functionality. This is way more solid than the earlier model. The capacity is maybe a bit more than is typically needed. And on my first "knock" it I was surprised to see splatter so high up on the back wall of the knockbox. We'll play with this prototype for a week, and if we like it, it's off to manufacturing.

    IMG_6306.jpg

    IMG_6304.jpg

  2. #632
    Join Date
    Apr 2016
    Location
    Hong Kong
    Posts
    465
    Post Thanks / Like
    Mentioned
    18 Post(s)

    Default why will it take so long to get my Decent Espresso Machine?

    Yesterday, I received this question via PM:
    I saw yesterday you mention that a realistic delivery date for regular release DE1's will be October now. Does the same apply for the DE1+? I ask because the website currently mentions a June 30 shipping timeframe for the DE1+. I was planning on pre-ordering one next week (when a paycheck arrives). It probably won't sway my decision, but a four month difference in shipping is something I'd like to plan for.
    I thought it was a very good question, that likely others were thinking, and so I asked the questioner if I could answer him publicly. Here goes. It's a long explanation. Sorry about that.

    WHY DOES IT TAKE SO LONG TO BUILD AN ESPRESSO MACHINE?

    In November, when we last built 8 machines, it took one person 5 full time days to build one Decent Espresso machine.

    There are a few reasons why this was the case with that November design, :
    - each building step was sequential, you had to do one, to do the next. That's slow.
    - physical access to the machine wasn't easy as things got packed into a small space
    - many steps were fiddly and required time to get right, such as mounting the steam wand through the faceplate in a way that was tight and not leaking when steaming
    - there were a lot of steps and many weren't easy, some requiring quite a bit of dexterity and assembly experience.

    For these reasons, and also because I felt the design of the internals was lacking the refinements that were needed, I sacked my mechanical engineer in January, hired a new one, and we've spent the past 4 months totally redoing the internal design to fix these issues.

    With the new design:
    - there are a half dozen sub-assembles, which are clusters of components that can be built ahead of time, and tested separately too.
    - getting into the machine is much easier, because there are panels where things mount that are removed from the machine, and screwed in at the end
    - hopefully, most of the fiddly, hard-to-get-right problems are fixed

    We're estimating that each machine will take a full person's day to make.


    WHEN WE TRANSITION TO BUILDING MACHINES:

    Some facts to bear on our transition to manufacturing:

    - we're currently a R&D company, and we have zero "factory workers" on staff who might build machines. To fix this, we're planning on hiring 8 Mechanical Engineering students as summer interns to build machines with us from June 1 to August 30. That gets us "smart people" to build the machines, and 3 months to transition to less highly qualified staff to be building them. I'm also hoping that these students will, by virtue of their studies, have insights for design improvements.

    - our office/R&D space (3200 sq ft) is almost totally full at the moment. We have another 2500 sq ft of warehousing, but that's full now too with parts. Why so much space? Because when you order a part (say, tablets) you have to order the minimum order quantity (1000 of them) and they show up in boxes, stacked up on pallets. You have to store them, and they take a lot of space. In June, we're taking out a lease on another 3500 sq ft, directly opposite our front door (6 ft away) and if orders start coming in over the summer, we're also going to take a lease out on another 6000 sq ft (around the corner). We're pretty organised, but it will take a bit of time to fit out the new spaces.

    - we don't yet have all the parts in stock, and some will certainly take longer to arrive than others. To work around this, we'll start building and testing sub-assemblies in quantity=200, so that when the parts all finally arrive, we're mostly done.

    - each espresso machine will be tested for 3 days before it ships: 24 hours on a shipping simulator machine, and then 48 hours of constantly making espresso and steam. This should expose most problems.


    WHAT TAKES SO LONG TO BUILD A DECENT ESPRESSO MACHINE?

    Building an espresso machine is similar to building a Tower PC clone machine. You buy parts, you put them into a chassis. However, there is one big difference: with a PC clone, all the parts come ready to be screwed in. With our espresso machine, lots of parts come and require more work from us before we can use them.


    AN EXAMPLE: THE HEATER SUB-ASSEMBLY

    We have two heaters in each machine (espresso and steam) and here are the steps for getting one heater ready:
    - put a temperature probe bead in the center hole, and back fill it with thermal putty
    - screw in two thermal fuses for CE compliance
    - screw in one thermostat for UL compliance
    - use pliers to connect locking power cables to fuse 1, to fuse 2, to thermostat, to electrical in, and also to ground
    - place entire heater (with all the fittings) suspended in a 3D printed mould of our own design
    - fill the mould with quick drying liquid silicone. Wait 30 minutes to dry. Remove and use a knife to clean up stray silicone. Let it further dry another 2 hours.
    - slide two two teflon tubes into the two water connectors (in/out) and use pliers to force in a tiny clip to hold them in place
    - put a cable tie into a teflon tube and wrap it around the heater, and then tie it to a metal panel
    - hook up the water lines to a water pressure line, and test under 15 bar for leaks
    - hook up the electrical lines to power, flow water at a known rate, and test that water is being heated at the rate expected
    - repeat again 399 times to make enough heaters for the 200 espresso machines that have already been ordered.

    Lots of steps! However, this approach is a good one because:
    - it's a major component and it can be built and tested totally independently from the rest of the espresso machine
    - it can be done in quantity, alone, so the people doing it can do it faster.
    - if we can guarantee quality, we can sub-contract out this assembly in the future. However, it has so many steps, and so many ways to screw up, and it is so vital a part, that for now we prefer to assemble it ourselves.


    SO: WHY OCTOBER TO RECEIVE MY MACHINE?

    Firstly: because there are 200 people ahead of you in the queue, and if we make 4 machines a day, it will take us 50 work days to build them, which is about 2 1/2 months on a 5 day work week. We're ordering parts now, but realistically of them won't arrive until the end of June, and no espresso machine can leave here until every last part is in stock.

    Secondly: we don't yet know how many man hours it will take to build a machine. We estimate it around 1 man day at the moment. If we can reduce that to half a day, that doubles our production speed. I don't think we can reduce it much below that, however, unless we contract out parts of our subassembly to other factories (effectively adding manpower).

    Thirdly: we need to hire a lot of people, train them, and have good processes for them to follow. If we do this too fast, we'll have bad staff, poorly trained, with bad processes.

    Fourthly: the order backlog is growing each week, and each new order goes to the back of the line.


    TO CONCLUDE

    This summer, we'll be making espresso machines.

    However, we can't go from "no machines per day with no factory workers" to "40 workers and 40 machines a day" in one step. Hiring and training and process-making will be incremental.

    We can't afford to sign leases for 3200 sq ft + 2500 sq ft + 3500 sq ft + 6000 sq ft (4 leases) unless we have some idea of demand. Growing capacity too fast is a good way to go bust.

    I expect that this summer, if our espresso machines are well reviewed, that orders will increase. We have a plan to cope with that demand, which you've read above. But, it will take a few months for us to deploy that plan.

    If you've been reading this forum for a while, one fact should have popped out at you: EVERYTHING DEPENDS ON INITIAL REVIEWS. That's why we're moving slowly, to ensure that from the very beginning, the machines that people receive are good, and people are pleased.

    In practical terms, what I expect is that if our espresso machines are well received, that they will be in short supply (like any popular new product) for the first 6 months, as we grow capacity to meet that demand.

    I hope this (too long) answer was interesting, and I'm happy to answer any questions.

  3. #633
    Join Date
    May 2015
    Posts
    942
    Post Thanks / Like
    Mentioned
    64 Post(s)

    Default

    I have to ask... Are the pucks normally that sloppy?

  4. #634
    Join Date
    Apr 2016
    Location
    Hong Kong
    Posts
    465
    Post Thanks / Like
    Mentioned
    18 Post(s)

    Default

    Quote Originally Posted by timmyjj21 View Post
    I have to ask... Are the pucks normally that sloppy?
    I tend to be lazy about changing basket sizes, and we're constantly changing grinder settings and coffee beans here. I'm currently putting 16.5g doses into my 18g basket, and so there's a puddle of water on top when I'm done. If I put 19g onto my 18g basket, no puddle. Apologies if my bad basket grooming habits offend.

  5. #635
    Join Date
    Apr 2016
    Location
    Hong Kong
    Posts
    465
    Post Thanks / Like
    Mentioned
    18 Post(s)

    Default USB charger for the tablet

    We've found what I think what will work well for providing a USB plug on the front splash panel, right near where the tablet needs to plug in. These two models below are:
    - minimally visible
    - the one on the right is watertight, the one on the left is probably water tight enough
    - USB-A, so we stay don't stray from the USB standard
    - the aesthetics of the two vary slightly

    We're ordering samples of these two today, and will likely settle on one of them.

    preview-full-preview-full-Screen Shot 2017-04-24 at 3.14.34 AM.jpg

  6. #636
    Join Date
    Apr 2016
    Location
    Hong Kong
    Posts
    465
    Post Thanks / Like
    Mentioned
    18 Post(s)

    Default One week to design freeze

    The current design of our Decent Espresso machine.

    Recent improvements:
    - hugely increased the "twisting" strength (aka stiffness) of the case, with additional bent panels (in the middle, on the top, under the group head)
    - hot water return is now as far away from the intake as it can be, so that calcium should precipitate during initial water heating and fall into the ceramic water tank where it causes no damage and can be rinsed out.
    - we've found an excellent, high speed temperature sensor (incredibly, with 0.2mm thick stainless steel walls) and now can stop using our hand-made-by-us sensor design (which was expensive and very time consuming). This has allowed us to add two more temperature sensors to the main mixing chamber.
    - however, the main mixing chamber now became too big to mould, so it's been broken down into two parts, which is why that part on the top (with all the bolts on it) has that odd shape.
    - most of the water tubing is now in CAD

    Still to be done:
    - a USB charger plug needs to be installed on the front panel (to the left of the group head)
    - our flush diffuser design needs to be finalized (it's too small at the moment)
    - the "cool touch" group head cover needs to be mounted
    - a panel separating the circuit boards from the machine needs to be installed
    - the "over pressure safety valve" integration needs to be finalized (that's the part floating above the bright green part)

    Looking at this CAD model now, I'm pleased that we took the extra months to rethink and/or refine everything. Nothing is crammed in, the wire paths are not hard to follow, and the design is fairly mature.

    screen 2017-04-24 at 10.30.46 AM.jpg

  7. #637
    Join Date
    Jun 2015
    Location
    London
    Posts
    182
    Post Thanks / Like
    Mentioned
    5 Post(s)

    Default

    Quote Originally Posted by decent_espresso View Post
    ...
    - USB-A, so we stay don't stray from the USB standard
    ...
    Just a thought: with USB-C set to become the new standard, I think this risks dating the machine very quickly.
    Adapters are available of course but my perception of a device which requires me to use an adapter to connect to my old hardware is very different to one which requires it to connect to my new hardware.
    That's assuming I'll be able to connect my own device full-stop, of course.

    "Coffee: The Good, The Bad, and The Ayurvedic Perspective"

    Behave yourself.


  8. #638
    Join Date
    Dec 2011
    Posts
    6,047
    Post Thanks / Like
    Mentioned
    81 Post(s)

    Default

    Why does the tablet plug in on the front, as opposed to the side/back or top?

  9. #639
    Join Date
    Apr 2016
    Location
    Hong Kong
    Posts
    465
    Post Thanks / Like
    Mentioned
    18 Post(s)

    Default

    Quote Originally Posted by Dylan View Post
    Why does the tablet plug in on the front, as opposed to the side/back or top?
    The top has a sliding cover, like a PC tower case, and anything that plugged into that would get in the way of the case sliding. We currently snake the cable to the back of the machine, and that works.

    However, the usb charging cable is an annoyance that grows more annoying the longer and less tamed it is. The goal of putting a charging port in front is that it's about 3" from the power port to the tablet.

    Quote Originally Posted by BaggaZee View Post
    Just a thought: with USB-C set to become the new standard, I think this risks dating the machine very quickly.
    Adapters are available of course but my perception of a device which requires me to use an adapter to connect to my old hardware is very different to one which requires it to connect to my new hardware.
    That's assuming I'll be able to connect my own device full-stop, of course.
    Interesting idea, thanks for suggesting it! I'm not currently seeing USB-C waterproof panel mount connectors, but we haven't looked for it, so we'll take a look and see if we find one.

    Yes, you can use your own device, and use our charging port. If you were USB-C, you would need a USB-A to USB-C cable.

    But let me get back to you about your USB-C idea.

    Ok, just spoke to my EE Ray about this idea, and he says that USB-C just for charging would require him to have a fully working USB circuit on his board, because there is a voltage negotiation step that occurs with USB-C, which isn't the case for USB-A. Given our design-freeze later this week, we don't want to embark on a "what will it take to add fully functioning USB-C to our circuit board?" R&D project.

    However, Ray says "it's a very good idea for rev 2".
    Last edited by decent_espresso; 24-04-17 at 11:42.

  10. #640
    Join Date
    Jun 2015
    Location
    London
    Posts
    182
    Post Thanks / Like
    Mentioned
    5 Post(s)

    Default

    I didn't realise that about USB-C. I've just had a bit of a read and it's clever stuff. Not so helpful in this case obviously!

    "Coffee: The Good, The Bad, and The Ayurvedic Perspective"

    Behave yourself.


Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Kruve Inc.

Important Site Information


Google Analytics Alternative