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Spitz.me
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#91: Post by Spitz.me »

Hey John,

The design is cool if you're into that sort of thing. I actually found the design to be the most appealing from the side and in white compared to the purple. Can you sell this kind of thing as an accessory like a "skin" or "wrap" instead of a case replacement? Regardless, I like that you're exploring new ways to make the machine interesting and different.
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caeffe
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#92: Post by caeffe »

Mods: Hopefully this is ok here, if not let me know and I can possibly pose the question elsewhere

Question re: the use of the BROR cart with the DE1+, I've gone through quite a bit of posts within here on HB and on the DECENT website and couldnt find an answer

It seems that you designed the top you sell on the site for the IKEA BROR cart using the DE1XL mainly - since I don't really mind the "messy" back but want the countersink look; will this work with the DE1+ and how does the DE1+ look countersunk? Does it sit lower and I'm assuming has enough clearance for the cables/tubes to exit through the back of the countersink bracket?

At one time it seems you were using the RIMFORSA as your cart - I like the RIMFORSA cart better due to the drawers on it but not sure if the BROR casters will work with it. Was the lack of casters (and probably cost) your rationale for going to the BROR?

RE: SCI SMORG
Not my cup of tea :) but I can see where Star Trek fans would love it. Maybe there's even a cafe out there with a Star Trek them or.... how about a Star Wars cantina theme!!
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TallDan
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#93: Post by TallDan »

The "Golden Era" has a certain modern art deco appeal. The smorg, as a design concept is definitely interesting. I'm looking at it like a concept car where the design is maybe intentionally over-the-top and in it's own way appealing, even if I may not be what I'd want in my driveway (bar, or kitchen). Then the Golden Era design is what the concept car becomes in production: A little more practical, a little less outlandish, even if it doesn't turn heads in quite the same way.

Personally, I think I'd be more interested in seeing some wood options. Might seem a little derivative of La Spaziale. Maybe bamboo? Frosted glass?

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decent_espresso (original poster)
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#94: Post by decent_espresso (original poster) »

caeffe wrote:It seems that you designed the top you sell on the site for the IKEA BROR cart using the DE1XL mainly - since I don't really mind the "messy" back but want the countersink look; will this work with the DE1+ and how does the DE1+ look countersunk? Does it sit lower and I'm assuming has enough clearance for the cables/tubes to exit through the back of the countersink bracket?
Yeah, you can put a DE1+ in the BROR cart. If you change the legs for DE1XL legs, you'll gain the 5mm or so that the DE1+ sits lower, but it's not that big a deal. In my videos from California, I've got a DE1PRO in my bror cart and it sinks just a bit lower than planned. Not a big deal, though.
caeffe wrote:At one time it seems you were using the RIMFORSA as your cart - I like the RIMFORSA cart better due to the drawers on it but not sure if the BROR casters will work with it. Was the lack of casters (and probably cost) your rationale for going to the BROR?
The RIMFORSA is gorgeous. The bamboo top is really heavy duty. However, because it is a thick tabletop, with two layers of bamboo, an air gap in the center of the top, and vertical support beams inside the top, it's a bit complicated to cut into and you have to take the drawers into account.

If you like IKEA's RIMFORSA I'd recommend you not countersink your DE1+. Just sit it on top. You can much more easily cut a 6cm hole for the tubing, than a large rectangular shape for the countersink.

If you like the all-in-one convenience of the BROR cart, go for the DE1+ now, and if someday you change your mind, we'll sell you the sheet metal parts to convert it into a DE1XL.
caeffe wrote: Not my cup of tea :) but I can see where Star Trek fans would love it. Maybe there's even a cafe out there with a Star Trek them or.... how about a Star Wars cantina theme!!
No worries, my goal was to have a small minority love it, and judging from the huge number of instagram comments and that about 30% were crazy for it, I think the design succeeds.
TallDan wrote:The "Golden Era" has a certain modern art deco appeal. The smorg, as a design concept is definitely interesting. I'm looking at it like a concept car where the design is maybe intentionally over-the-top and in it's own way appealing, even if I may not be what I'd want in my driveway (bar, or kitchen). Then the Golden Era design is what the concept car becomes in production: A little more practical, a little less outlandish, even if it doesn't turn heads in quite the same way. Personally, I think I'd be more interested in seeing some wood options. Might seem a little derivative of La Spaziale. Maybe bamboo? Frosted glass?
We've tried drawing various ideas for wood options, but the current Dieter Rams https://en.wikipedia.org/wiki/Dieter_Rams inspired Decent Design does not accommodate wood accents well, except for touch points like handles.

My aim is to "solve" the mechanical issues of re-skinning the Decent next year, with Smorg, and then if there is demand (and time) explore other designs with talented people who come into our periphery.

I would absolutely love to have a wood Decent, but I'd want to really take advantage of the natural properties of this material, and not treat it like steel.

Here is an idea in wood that I admire, whose idea could be applied to a Decent chassis. If we use wood, I think it should flow.

-john


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decent_espresso (original poster)
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#95: Post by decent_espresso (original poster) »

Decent working with Weber Workshops

I've long admired Douglas Weber's many products, from the EG-1 grinder that I own, the HG-1 grinder that I've used, the steam dial. Even the stuff he makes that I don't like, I still admire because it's always bold, inventive, and high quality.

From when we started Decent, I'd hoped Decent could be seen as the other highly-creative company in espresso.

So it was with great pleasure to get a Whatsapp from Douglas Weber some weeks ago. We chatted for about 2 hours, and talked about ways we could work together. It was fascinating to find how many stories and viewpoints we shared.

Today Douglas announced https://www.instagram.com/weberworkshops/ a Decent adaptor for his Steam Dial tip:




I have used the steam dial, years ago, on the two group E61 I owned. I loved it. Sadly, the threads were incompatible with the Decent, until now.

Also, a few weeks ago he announced that he'd tested his new Spring Clean https://weberworkshops.com/products/spring-clean product on the DE1 he owns and can confirm it works well with Decent espresso machines.




As our working together is based on mutual admiration and similar philosophies, I'm looking forward to see what we can do together, in the future.

-john

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#96: Post by decent_espresso (original poster) »

Why no 3 way valve?

During the first few years we started making the Decent Espresso Machine, I would often hear criticism that the Decent "lacked" a 3 way valve and thus did not flush properly at the end of espresso.

I patiently repeated my answer that this was not a lack at all, but a decision we made because it seemed to us that using the same tube from the water heater to the group, both for clean water in (to make espresso) and dirty water out (to release pressure) was a bad idea.

All espresso machines (that I know of) before Decent did this "backflush". We thought that coffee oils would likely build up in that tube, go rancid, and slowly degrade the quality of future coffee.

But our position was alone. Nobody else backed us up or agreed with it.

And people usually didn't believe my explanation, likely because we were the only ones (it seemed) arguing this position. I think people thought I was trying to do "marketing spin" on a "problem with the product" instead of perhaps, maybe having a valid point.

Until I read James Hoffman's "Best of 11 years' writing" book https://decentespresso.com/books where I found out that he'd explicitly called this out as a common source of bad tasting espresso, and thus how important it was to clean this part on conventional espresso machines.





James wrote this 4 years before we even started designing the Decent! I wish he'd published this book earlier.

Here's the relevant quote from his book:




With the Decent, we release pressure through a separate tube that only ever is used for dirty water. The clean-water-in path holds its its pressure at the end of espresso, forcing water out this path.

Here is a photo of the inside of the group head on a Decent:




The brown tube brings water in (brown=making nice coffee) and the black tube on the right (black=dirty) flushes it away.

We call this approach "forward flush" to oppose it to "backflushing"

It's been a few years since I've heard the "why don't you flush like a normal machine" criticism but I think it's still not commonly known that this common design feature of traditional machines is not great.

This topic came up yesterday, because part of the goal of Weber Workshops new Spring Clean https://weberworkshops.com/products/spring-clean product is to clean this "backflush tube". Decent owners were asking whether it was worth buying Spring Clean, given that we don't have this same cleaning problem as traditional machines. I don't know yet, but I'll be getting a Spring Clean myself soon, for testing, and will report back what I find, about the job it does on a Decent.

-john
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decent_espresso (original poster)
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#97: Post by decent_espresso (original poster) »

What we learned by delaying v1.4 for ten days

We finished building our first 50 v1.4 machines in early September, about a month ahead of schedule.

During our temperature accuracy test, we found that about 30% of the machines were not acting as they should, with water temperature about 2ºC above the goal temperature.




All 50 machines were identical, so what could be the problem?

We tried a variety of theories.
- Maybe the flow constrictors were mis-mounted?
- Maybe the temperature probes were of varying quality?
- Maybe the pumps were defective?
- None of our theories were right.

So, we proceeded to take 1 part at a time out of a "good" machine, and replace it in the "bad" machine, until the problem re-appeared.

The problem finally re-appeared when we replaced the section where "water mixing" happens. That's where 110ºC superheated water meets room temperature water, at varying flow rates, so that we can give you the exact water temperature you want.

So then we started taking the "bad" parts apart, and measuring everything. We couldn't find any difference between the "good" and "bad" part.

After 4 days of delays, I decided to put all 50 machines aside, and start building another 50. I then assigned 3 engineers onto the problem full time here in Hong Kong, while Ray (Seattle) and Ben (Australia) also worked on this issue remotely.

We eventually figured out that no component was defective. The problem was a temperature sensor we'd moved.




We had moved the temperature sensor closer to the point where the water mixing happens. The new position gave us slightly faster sensor feedback. We'd been testing this for almost a year with no problems, so why does it not work now?

We finally figured it out.

The new temperature probe location is right where the hot and cold water mix.

It turns out that teeny tiny changes in the angle of water flowing into this mixing chamber, caused big changes in how well, and how evenly, the two different water flows mixed.

With slight differences in angle, the new temperature probe location was measuring ever so slightly more cold water than would eventually be in the final mix. And therefore our mathematics were compensating for that cooler water by putting warmer water in. Which then gave us 2ºC hotter water, when finally measured at the coffee puck.

The bright yellow and green water tube in the upper right part of the photo, is carrying mixed water to the "old position" temperature sensor. That tube is only 1.2mm wide. There's not much water in there.

It turns out that squeezing the mixed water from the chamber, through the tube and back into a chamber, causes the water to be thoroughly and evenly mixed. Measuring the water temperature earlier gave use readings that still had hot and cold eddies flowing around.

Once we figured this out, we moved the temperature probe back to the old position, and all our machines now worked as expected.

The exercise, though stressful, was quite worthwhile. We learned something new about measuring water temperature, and mixing, and eddies.

In our latest firmware (about to be released), insights from these ten days have led to revisions to our mathematics, and specifically we now are able to stabilize our coffee puck temperature significantly better, with very slow "thick" shots that have very little added water through them. This has been a case where we typically ran about 1ºC too cool at the end of the shot, and we'd not been able to understand why. Our better understanding of water mixing dynamics has helped Ray to crack that problem.

We've never before achieved this level of "measured at the puck" temperature accuracy, with such slow shots (in my test, a 38 second espresso).

Note how, in the photo, the puck temperature is only 2ºC too cool at the start, thanks to our slight 2ºC over-temperature bump for the first 2 seconds. Traditional machines typically start 6ºC to 8ºC cooler than the goal, because the puck is at room temperature. And then the rest of the shot manages to stay with 0.3ºC at the coffee puck, during the entire shot. I'm happy!


Don Task
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#98: Post by Don Task »

Thanks John, very impressive! Your creative ambition, your dedication to your products, along with your persistence and tenacity is heart warming and admirable. Having a background in manufacturing I for one can appreciate the time and expense involved with doing this level of trouble shooting and research. I only wish every manufacturer, regardless of the product, would demonstrate such devotion and enthusiasm in delivering a quality product.
Krups, then Silvia, then Livia 90, then a Techno! Does it ever end? [sigh]

sems
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#99: Post by sems »

John, your manufacturing adventures and updates are very interesting to read from engineering and coffeemaking perspectives. I'd suggest you collect these and these might eventually lead to a 'experiences and thoughts' kind of book just like James'.

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#100: Post by decent_espresso (original poster) »




A new way of addressing the Decent backlog

If you've been watching our order queue https://decentespresso.com/queue you might have noticed two things:

1) the queue has been getting longer
2) the order of the queue is a thorough mix of different models and voltages

We've been sloooowly improving our speed of making machines, from 17/week in January, to 23/week in August. Progress has been too slow.

I've been removing complexity everywhere I can find it, in an effort to speed things up.

In the past, we've done "mixed runs" of different models and voltages. No more. That slowed us down.

Now, each week, we build 50 of whatever model has the most number of backlogged orders. You can see that list on the bottom right of the photo.

Even though we have 270+ orders backlogged, this is spread over quite a few models. One effect of this "one model only" change is that we will, at times, have built more machines of that model than have orders. Wow, stock-at-hand of Decent machines! That would be nice.

I wrote recently that I switched to a "master" system, where we build 50 machines at once, and there's an employee who is designated the "master" of a sub-assembly. The build it, test it, install it, and train their apprentice. That way, they know what to do, every day. No need to micromanage.

My idea was that as we've completely build 50 machines, we'd move to the 2nd assembly table, where we'd start building another 50 while the previous ones were tested.

That basic idea worked well enough. We were able to build 50 machines in 8 days, or 150 machines/month, assuming a 6 day workweek.

We ended up modifying that idea, though, because I managed to speed up testing quite a bit with new software and test equipment, so that it now takes 4 days for two people to test and calibrate 50 machines. That means the assembly line is free on day 5. And it turns out that at around when the 50 machines are 60% built, we have the staff available to start building the next round of 50 machines. This "overlapping build cycles" tweak, this has allowed us to build 50 machines in 6 days.

With a 6 day workweek, that's 200 espresso machines/month. Now, we're finally getting somewhere! At that pace, we can make 44 machines more than were sold (we sold 156 espresso machines last month) and so make progress at the backlog. Previously, sales were growing so much faster than our speed of building, that we were getting progressively further behind.

I don't know that we're going to succeed, but my hope is be totally up to date with our backlog by the time Christmas comes along, so I can give my employees a well deserved break and maybe a bit of a Christmas present as well.

And ideally, every client who ordered would have received their machine by then.

I might be dreaming, but it's good to have goals!

What can slow us down is if we don't have enough time to get the "sub assemblies" done in order to keep up this pace. Small problems, like the recent "group head handle position" problem, lost us a day and a half (not too bad) and slow us down.

-john

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