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Did you ever get around to redesigning/customing the grinder's nozzle, to minimize clumping?

 

Will it be possible (future proof) to wire up the grinder with an upcoming Decent Bluetooth scale?

 

 

I thought it was discussed a bit more in this thread, but all I can find is this post

 

But I seem to remember DE saying that they didn't want to provide a DIY kit because of the risks involved in opening up a grinder.

 

Their scales have bluetooth with an open API however - so would only take the right person to create a DIY kit that could use the scales - a little like this with the Acaia:

 

[video=youtube;-dustqnN-MA]

 

Edit: just realised this video may very well be from someone at Decent Espresso - as the creator links back to the DE website int he comments.

Edited by Dylan

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Did you ever get around to redesigning/customing the grinder's nozzle, to minimize clumping?

We did try a few different shapes, and ended up with a teflon coated spout. The spout doesn't cause clumping, but a very fine grind or high humidity will still cause clumping, as it does on most grinders.

 

Will it be possible (future proof) to wire up the grinder with an upcoming Decent Bluetooth scale?

Not likely, unfortunately, because the bluetooth module we have in our testing grinder did cause two engineers to get shocked learning to install it, so I'm very leary of selling something to people and asking them to do something will likely cause them to be electrocuted.

 

The two engineers now know how to put the module into the system without being shocked, but the fact that one Mechanical Engineer and another Hardware Hacker got shocked doesn't give me great confidence in this being anything but a qualified electrician should be doing.

 

We did pursue another approach for a while, using a bluetooth controlled power plug, but that company never came through on their promise of a 220V version (it's only 110V and ungrounded at that). Plus, that approach can only turn the grinder off, not on, so it's not as flexible as the embedded bluetooth controller inside the grinder.

 

I thought it was discussed a bit more in this thread, but all I can find is this post

But I seem to remember DE saying that they didn't want to provide a DIY kit because of the risks involved in opening up a grinder.

Their scales have bluetooth with an open API however - so would only take the right person to create a DIY kit that could use the scales - a little like this with the Acaia:

Edit: just realised this video may very well be from someone at Decent Espresso - as the creator links back to the DE website int he comments.

Yes, that video was from Haroldo, who worked for me for a year, and brought his invention along. However, the idea of adding weighed dosing to existing grinders hit the Mechanical Reality ™ that most grinders don't have enough space to fit a scale under the grinder spout. Add to that the fact that Acaia decided to close the API to their scales, and that seemingly-almost-ready-to-ship product was an R&D cul de sac, and was killed about a year ago.

 

Sadly, not all R&D paths lead to products, as was the case with Haroldo's idea.

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Thanks to "chemical engineer/coffee nerd" DIYCoffeeGuy for plotting 182 espresso shots we've made on my DE1+ espresso machine.

 

We do a huge amount of experimenting with grinds, grinders and roasts, so there's a lot of data all-over-the-place. The "pressure vs time" chart isn't especially enlightening to me (it shows that we're experimenting a lot and our pressure is all over the map). I'm not the only one using this machine, so lots of other people's experiments are plotted here, which accounts for some of the variability.

 

However, the flow vs time chart is a lot more interesting. Here are some takeaways from the data:

1) our pre-infusions are mostly around 4ml/second, but plenty around 2.5ml/second too

2) most shots have their pucks compressing around 6 seconds, and fully compressed by ten seconds (by looking at the slowdown in flow possible through the puck)

3) most of our shots are around 2.5 ml/s during the main extraction, though there is a healthy number of slower extractions around 1.8 ml/s

4) most of our shots end around 25s, some go to 35s, but very few beyond.

 

This sort of visualization is interesting to me for a few reasons:

1) it helps prove that I (the DE1+ tablet programmer) don't have all the answers and that others have other perspectives on the same data

2) data export from the DE1+, especially over a large sample size and in a cafe production use, could yield interesting and new insights. This sort of data is not usually collected outside of lab settings.

3) some of these visualizations that people do will make their way back into the DE1+ tablet software, other will be programmed by either me or anyone-who-wants-to using Javascript, once I integrate our espresso machines into the cloud, and make this data publicly crunchable.

 

You can visit DIY's Instagram post

for more charts of the same data.

 

flow_vs_time.jpg

 

pressure_vs_time.jpg

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Getting electrocuted was what i thought you gave as a reason before.

 

I electrocuted myself in the cheek (scared the shit out of me, predictably) installing and Auber timer, so your concerns are more than valid.

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One is tempted to ask why anybody would be wiring something up Live ??

 

Live testing OK but with great care. Wiring ?? Absolutely not.

 

Anytime you are working inside the machine it should be unplugged unless you are testing for a voltage and for that use probes.

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I electrocuted myself in the cheek....

 

I'm sorry, I'm really sorry but I have tears rolling down my face from laughing. This story surely qualifies for the Master Muppetry thread.


Espresso: Ceado E92 (modified for single dose); Vesuvius; VST baskets and refractometer.

Other: Aeropress, Sowden and Alessi Moka Pot; Mazzer Robur doser with Auber timer; Mazzer Mini E; Expobar Leva Dual Boiler

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Live testing OK but with great care. Wiring ?? Absolutely not.

 

Sometimes I understand why there are Darwin awards :angel:


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Getting electrocuted was what i thought you gave as a reason before.

 

I electrocuted myself in the cheek (scared the shit out of me, predictably) installing and Auber timer, so your concerns are more than valid.

 

Thank goodness you lived to tell the tale (and nab my spare Acme cups!)


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Yup, i can see the funny side. I thought i had unplugged it but actually unplugged the machine instead. Lent over the grinder to look inside and got a jolt to the cheek, which made me head but the cupboard above.

 

For about half a second i thought i had blinded myself, which was what scared the shit out of me, i probably wasn't far off doing so.

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I've sort of lost track of this very long thread....does anyone on the forum actually have a decent espresso machine yet?


 My reviews at https://coffeeequipmentreviews.wordpress.com/ - Various Machines and grinders, Amazon Dalian 1kg Drum Roaster: YouTube channel at https://tinyurl.com/szhgxzl .......

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For about half a second i thought i had blinded myself, which was what scared the shit out of me, i probably wasn't far off doing so.

 

Not so funny really. Glad you're ok. Still a candidate for the muppetry thread though. There's some very good company in there.


Espresso: Ceado E92 (modified for single dose); Vesuvius; VST baskets and refractometer.

Other: Aeropress, Sowden and Alessi Moka Pot; Mazzer Robur doser with Auber timer; Mazzer Mini E; Expobar Leva Dual Boiler

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I've sort of lost track of this very long thread....does anyone on the forum actually have a decent espresso machine yet?

 

Our first manufacturing run of 300 espresso machines has now sold out.

 

We are not taking new orders for espresso machines until we start shipping.

 

Once shipping, we will take orders for our winter 2017 manufacturing run, delivering those machines in early spring.

 

I guess that is a no just now

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Not so funny really. Glad you're ok. Still a candidate for the muppetry thread though. There's some very good company in there.

 

Indeed, if there is a competition with prize perhaps I'll enter ^_^

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Last week, Ray had a worry that tension from bending a tube might cause the water seal to fail sooner. While none of our connections is leaking now (even under tension), everyone agreed that it would be better to not have uneven tension on the water seal.

To research if any other manufacturer also worried about this, Jeff went diving through our morgue of dead & disassembled espresso machines. He found one Nespresso machine that apparently had this same worry because that machine had little plastic moulded de-tensioners to hold 90º and 180º bends in place.

Alex drew up a SolidWorks model inspired by what Jeff had found, and over the weekend he 3D printed our de-tensioners. There's a photo below, showing where they'll go in. They work nicely, and we'll be using them in all the machines we're building.

This may or may not be an issue, but with these detentioners costing about $0.10 each, it'd be crazy to not use them to make the worry go away.

 

IMG_6930j.jpg

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A few weeks ago, I mentioned that one of our last engineering problems was to decide how to insulate our two heaters.

 

Our interns built a test rig, with a tiny Arduino computer, at both 100ºC and 170º, to test all the different ideas we had.

 

Originally, we liked silicone, but our first batch had a nasty chemical smell when heated. Two other manufacturer's samples also had a smell. Also, it's very hard to get air bubbles into the silicone, so the pure silicone insulating solution adds a lot of weight, and is not as insulating as it could be.

 

We thought we'd solved that problem when we found a no-smell silicone mix that bubbles when mixed, to a selectable amount between 10% and 30%. The problem is that it's extremely hard to get into a mould and in a regular shape. Immediately upon mixing it swells about 60% but then overnight, as it dries, it continues to swell unpredictably. You end up with a messy "pillow" in the morning.

 

We tried making a metal mould to contain the expanding foam, and that helped, but it left some areas under-covered as the foam expands in ways that differ each time (presumably because of uneven distribution of the foaming agent).

 

Ray realized that PC boards are made of fiberglass, an excellent insulator, and they're very cheap to have cut into custom 2D shapes. So, he designed a fiberglass box for our heater made from PCB, which is then soldered together.

 

It's a bit of an oddball solution, but it worked quite well.

 

We then tried foaming silicone inside the box, and the thermal insulation results were amazing--the best yet--but it was really hard to do and the results are very irregular and not pretty.

 

In the spreadsheet below, you'll see the results from all our materials, and you'll see that the air temperature (that's the important metric) is OK for all of them. We want to keep it under 40ºC inside the DE1, and all our solutions have done that. You'll notice that PCB+Foam is the best performing, though, by a small amount.

 

Today, we're doing our final test, which is placing a pre-cut insulating blanket inside the PCB box, wrapped around the heater. We're expecting that it'll give us a lot of the same insulating benefit of the silicone foam, but be much, much easier and faster to assemble (no pouring into a mould and waiting overnight).

 

Below are photos of the various attempts and tests we've done, for those interested in following along with our progress.

 

We're awaiting the parts for our "release candidate #3" which are due in about 7 days. That machine will likely use this PCB Box + Blanker heater insulating technique, which is what we'll use for the 300 machines we're building.

 

heaters1.jpg

 

heat-table.jpg

heaters2.jpg

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Pcb laminate will degrade with time if it gets too hot. You can buy it in a high temperature rated version though. What about ceramic fibre blanket?

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Pcb laminate will degrade with time if it gets too hot. You can buy it in a high temperature rated version though. What about ceramic fibre blanket?

Understood. We're using single layer boards, without laminate, and uncoated as well. We're pretty sure that makes the "PCB" nothing but a single layer sheet of fiberglass.

 

If you disagree, please do please let me know, as there are lots of options with PCB.

 

Regarding a blanket, the problem is that if there are air gaps, heat will flow out of them. Our heaters are small with lots of connectors that get in the way of a simple blanket pattern. With big espresso machine boilers, the connectors are (by percentage) a small part of the total surface area, and less of an issue. We liked the idea of a silicone dip, because it ensured no air gaps, and we might still figure that one out, but since the PCB solution works well enough, we're going with that for now. We're not going to hold production to find an optimal solution, as all the insulators tested as staying under 40ºC.

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Understood. We're using single layer boards, without laminate, and uncoated as well. We're pretty sure that makes the "PCB" nothing but a single layer sheet of fiberglass.

 

If you disagree, please do please let me know, as there are lots of options with PCB.

 

Regarding a blanket, the problem is that if there are air gaps, heat will flow out of them. Our heaters are small with lots of connectors that get in the way of a simple blanket pattern. With big espresso machine boilers, the connectors are (by percentage) a small part of the total surface area, and less of an issue. We liked the idea of a silicone dip, because it ensured no air gaps, and we might still figure that one out, but since the PCB solution works well enough, we're going with that for now. We're not going to hold production to find an optimal solution, as all the insulators tested as staying under 40ºC.

Probably ok if the laminate isn't touching a hot surface. Get the fr4 175 degree rated material. I don't think there is much cost difference.

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Probably ok if the laminate isn't touching a hot surface. Get the fr4 175 degree rated material. I don't think there is much cost difference.

Thanks, that's helpful.

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For busy cafes, I've often received emails from baristas worrying that wet fingers won't work well on our tablet. It's true that if you get water on a touch screen tablet, you need to wipe it off for the touch function to work well. Wet fingers, on the other hand, don't seem to be a problem: water drops on the tablet do.

 

The medical, dental and beauty industries all have foot pedals for dealing with this problem, freeing up your hands to do something else.

 

I especially like the idea of a foot pedal for steam, because I sometimes destabilize the milk jug as I let go with my left hand to turn the steam off.

 

You could even put away our Android tablet and make espresso drinks only using the pedals.

 

I've done a quick look at available foot pedals and here are some features I'm looking for:

- can cope with a wet floor (raised off the floor)

- can cope with water poured directly on the footswitch (IP64 or IP65)

- colour coded so you can easily tell the difference between steam/hot-water/espresso buttons

- comes in 1, 2, and 3 pedal versions, so that people can choose what espresso functions to move to a foot pedal

- the pedal design makes it unlikely to push the wrong one

- rugged

 

The picture below shows 3 variations of one pedal design that meets those requirements. There is also a compact two-pedal variant from this company that is more attractive but also more confusing to use.

 

My mine "gripe" with this design (and pretty much all industrial foot pedals) is that the colour scheme is chosen for functionality, not aesthetics. The light blue colour of the "chassis" is a bit "hospital" for me. I'm asking if we can choose a different coloured plastic for our versions.

 

These foot pedals would plug into the bottom of our DE1CAFE machines, and provide a mechanical alternative to using the tablet. You can keep the tablet around to see the shot quality or put it away completely.

pedals1.jpg

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Several months ago, here and on other forums, we had a big discussion about what form a USB charger built into the DE1 should look like. In our current "Release Candidate 2" espresso machine we had all the bits to wire it up (and the PCB was supposed to support it) but we'd never done so.

 

Our first attempt, when we thought things were working, blew up a tablet (smoke!) and then a USB fan. We discovered that the problem was a "sample USB cable" that had been made for us to consider, had been wired backwards. Sigh. New cable and tablet, and now everything works.

 

1.28 amps are the most I've ever seen get into my tablet, and we're getting that charging from the DE1. Note that USB charging turns off automatically when you're making an espresso or steam because we use all the power to make sure those functions work right.

 

The USB charger and panel-mounted USB-female connector are both sealed and meant to be used in wet environments.

 

usb2.jpg

usb1.jpg

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Several months ago, here and on other forums, we had a big discussion about what form a USB charger built into the DE1 should look like. . . . New cable and tablet, and now everything works.

So happy to read this, and to know that my DE1+ will only need to be plugged into the wall once.

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Our alternative to the "Scace II", a tool for measuring temperature and pressure, is making progress. We're sending off the design to have one made this week. We're calling it the "Decent Sensor Basket".

We've made several revisions to the design I posted a few weeks ago.

We've placed an easily removed "splash shield" in front of the pressure sensor, so that water coming in doesn't cause noise on the sensor, but also so that if your machine is dirty and coffee material gets into the sensors, it's easy to clean it out.

We've changed the water outlet to a standard barb so that a flow meter could be attached to it in the future. Also, this makes it easy to attach a rubber hose to the outlet and guide waste water to a receptacle.

To change the calibrated flow constrictor, and thus have a different speed of water flow, you now pull the plastic sleeve out, use a paperclip to change the flow constrictor and push it all back in. This is also what you can do if coffee debris clogs up the outlet.

Instead of a complete portafilter, we're putting all the sensors into a portafilter basket, so it'll work with any bottomless portafilter that fits 58mm standard baskets. La Marzocco and Nuova Simonelli both follow this standard, but the location of the "wings" on their portafilters is different. Since you'll be using their bottomless portafilter with our basket, there's no problem.

When the Sensor Basket hardware arrives in about 10 days, we'll wire it up to an Arduino, with an LED display, write a bit of software, and start using it to test and calibrate our DE1 espresso machine. Every pump and flow meter is slightly different in the real world, so every espresso machine needs to be calibrated before it goes out to a client.

preview-lightbox-ASM, Sensor Basket_V2.jpg

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Our alternative to the "Scace II", a tool for measuring temperature and pressure, is making progress. We're sending off the design to have one made this week. We're calling it the "Decent Sensor Basket".

We've made several revisions to the design I posted a few weeks ago.

We've placed an easily removed "splash shield" in front of the pressure sensor, so that water coming in doesn't cause noise on the sensor, but also so that if your machine is dirty and coffee material gets into the sensors, it's easy to clean it out.

We've changed the water outlet to a standard barb so that a flow meter could be attached to it in the future. Also, this makes it easy to attach a rubber hose to the outlet and guide waste water to a receptacle.

To change the calibrated flow constrictor, and thus have a different speed of water flow, you now pull the plastic sleeve out, use a paperclip to change the flow constrictor and push it all back in. This is also what you can do if coffee debris clogs up the outlet.

Instead of a complete portafilter, we're putting all the sensors into a portafilter basket, so it'll work with any bottomless portafilter that fits 58mm standard baskets. La Marzocco and Nuova Simonelli both follow this standard, but the location of the "wings" on their portafilters is different. Since you'll be using their bottomless portafilter with our basket, there's no problem.

When the Sensor Basket hardware arrives in about 10 days, we'll wire it up to an Arduino, with an LED display, write a bit of software, and start using it to test and calibrate our DE1 espresso machine. Every pump and flow meter is slightly different in the real world, so every espresso machine needs to be calibrated before it goes out to a client.

[ATTACH=CONFIG]28584[/ATTACH]

 

Now this would be something!


Sage Bambino - BWT Bestmax - Niche in Black. Aeropress and Aergrind

 

Live and Let Live

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Our alternative to the "Scace II", a tool for measuring temperature and pressure, is making progress. We're sending off the design to have one made this week. We're calling it the "Decent Sensor Basket".

We've made several revisions to the design I posted a few weeks ago.

We've placed an easily removed "splash shield" in front of the pressure sensor, so that water coming in doesn't cause noise on the sensor, but also so that if your machine is dirty and coffee material gets into the sensors, it's easy to clean it out.

We've changed the water outlet to a standard barb so that a flow meter could be attached to it in the future. Also, this makes it easy to attach a rubber hose to the outlet and guide waste water to a receptacle.

To change the calibrated flow constrictor, and thus have a different speed of water flow, you now pull the plastic sleeve out, use a paperclip to change the flow constrictor and push it all back in. This is also what you can do if coffee debris clogs up the outlet.

Instead of a complete portafilter, we're putting all the sensors into a portafilter basket, so it'll work with any bottomless portafilter that fits 58mm standard baskets. La Marzocco and Nuova Simonelli both follow this standard, but the location of the "wings" on their portafilters is different. Since you'll be using their bottomless portafilter with our basket, there's no problem.

When the Sensor Basket hardware arrives in about 10 days, we'll wire it up to an Arduino, with an LED display, write a bit of software, and start using it to test and calibrate our DE1 espresso machine. Every pump and flow meter is slightly different in the real world, so every espresso machine needs to be calibrated before it goes out to a client.

[ATTACH=CONFIG]28584[/ATTACH]

Will it be possible to build this into a smaller basket too, fitting eg. Dalla Corte machines?

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