Kelvin Home Coffee Roaster

Production + Timeline Update
almost 5 years ago – Sat, Nov 02, 2019 at 01:25:17 AM

Greetings Backers,

We know that you all are extremely eager to begin roasting with Kelvin, and appreciate your patience as we approach the finish line of shipping!

In this update, we will provide a detailed look at the testing process we’ve undergone as we work through feedback from our first round of UL testing. We are happy to report that we’ve been able to solve each issue we encountered and detailed descriptions are included below.

Before we dive in, we’d like to share an important timeline update…

Timeline Update

As we discussed in our last update, the only reason we would not hit our expected timeline was if we required more rounds of testing. Unfortunately, our team uncovered (and solved) two issues that required multiple rounds of internal troubleshooting over the last month in order to be confident in sending Kelvin back to UL. Due to the additional testing required in the last month, our expected delivery date has been pushed back to early 2020. It is important to us that we stay committed to being completely transparent with our backers and inform you of our realistic timeline goals.

Our team is just as eager as our backers to begin shipping, and are exploring ways to trim down our lead time as much as possible. As soon as UL/IEC testing is complete, we will release an immediate update on UL/IEC results, as well as an updated timeline for when to expect your Kelvin.

A Delicate Balance: Safety & Functionality

The reason for conducting a wide variety of tests over the last month was not only to confirm the changes needed for UL/IEC testing, but also to confirm a few key aspects of the functionality of Kelvin once those modifications were implemented. A big part of that process for a complex product like Kelvin is about balancing two things: the roaster safety and functionality. We’ve talked about our commitment to safety before; while safety remains a top priority, we are also focusing on maintaining optimal functionality without sacrificing safety.

To address a few key points of feedback from UL before completing our internal testing, we implemented both software and hardware enhancements to Kelvin.

SOFTWARE

On the software side, we included a function that monitors the output temperature of the heater. If a sensor monitoring the heater does not detect a certain minimum temperature after the roaster has been running for a given amount of time, this indicates that there are no beans in the chamber (no load) and the heater will go into a lower power mode. This works well to address potential conditions where the roaster could be running with no beans — like if it tipped over on its side or was started by accident. Unfortunately, it also introduced a few instances in our testing where it cut out the heater under normal use. See the image below to see temperature data from our testing showing this issue. This issue has been identified and solved in our next software build.

HARDWARE

On the hardware side, there is also a physical over-temp safety cutoff switch that is a fail safe mechanism for any scenario where the roaster exceeds a safe operating temperature. This hardware heater cutoff is actually a very clever little mechanical device that opens up a switch (turns off the heater) when it gets too hot and then closes the switch (turns on the heater) when it cools back down. This again works well in our extreme use scenarios as a safety cutoff, but under some normal roasting conditions we saw the heater cutoff. See the image below to see temperature data from our testing showing this issue. This item has been identified and solved with a new cutoff switch with an adjusted high temperature limit.

The interesting thing about both of these functional issues is that UL wouldn’t have cared about the impact that either of them have on creating high-quality roasted coffee. We conducted this additional testing to ensure that we would be in a good place for UL/IEC testing AND to make sure the roaster will function well for our users. If we didn’t do this exhaustive testing now and had to make changes down the road, it could require retesting for our UL/IEC testing certifications. See the image below for one example of how these conditions were impacting our roast testing results, with the same roaster intermittently showing different behaviors.

With these items corrected (along with some other optimizations for low/high voltage, airflow, different bean characteristics, etc.) we are currently in what we anticipate to be the final iteration before heading back into UL and IEC testing. As of now, we expect to receive sample roasters with these enhancements early next week (unfortunately, one side effect of having an international design and manufacturing team is the transit time in sending samples back and forth). If these additional samples are able to produce the same results as our current roasters, we will send Kelvin back to UL. We’re as close as we’ve ever been and your patience will be rewarded with the quality of the end product!

As always, let us know if you have any questions by sending us a direct message, or emailing us at [email protected].

Best,

Team Kelvin

Safety Testing + Green Bean Lineup
about 5 years ago – Fri, Sep 13, 2019 at 12:25:39 AM

Hello Backers,

We’ve had a busy month since our last update, including lots on both the Kelvin roaster and the green bean sourcing. We have many updates below, including some details of the safety testing to highlight the many items we’ve been solving for to make Kelvin comply with those important global regulations. Let’s dive in…

Timeline Update

The key item that we know many of you are interested in is our timeline for shipping. Due to some of the details raised by the testing lab (sometimes in conflicting ways to what the standard actually says), we’ve had to take some extra time to solve for those items. We’re including details below to show that this is not due to any lack of effort on the part of our team, who has been working very hard to creatively and rigorously solve for each item raised.

Our current timeline is to deliver your Kelvin Roasters before Dec. 23rd. The only reason this wouldn't happen is if our testing requires another round. We are working very hard to insure that doesn't happen! We’ll continue to keep you posted as soon as we get additional testing results. We’re as excited as you are to get Kelvin out into the world and continue to honor our commitment to you, our supportive community, to bring you the best product possible, as soon as possible!

On to the details...

UL/IEC Testing Update

We are working our way through UL (for the 110-120V version) and IEC (for the 220-240V version) safety tests, making steady progress. One big factor in the UL/IEC testing process that we are working through right now is the fact that the standards are written for certain classes of appliances, but how exactly that standard is being applied to a given appliance varies based on the individual appliance being analyzed. They also don’t make these determinations and interpretations until physical samples are submitted. Further complicating matters, the standards requirements are slightly different and permit (or require) slightly different ways of resolving items. This is a complicated way of saying that, we’re being tested by standards that can apply to everything from toaster ovens to slow cookers and we’ve found that sometimes it is not always clear how they will be applied to a coffee roaster, or even our specific coffee roaster.

Here are just a few examples:

HEATER ASSEMBLY

One major part of the Safety testing is a construction review, where the roaster is analyzed to make sure the internal components are assembled in a safe way. This required many minor changes, all of which we have solved for, such as relocating the mountings for one of the temperature sensors on the heater because when assembled, it was too close to the metal shroud:

  Another component change was on the barrier between the heater and the metal shroud that funnels the hot air into the roast chamber. After receiving  changing guidance as to how many layers of mica insulation were needed between the heater and the shroud (UL requires 1, IEC first said 3 then 4…) we were eventually informed that adding a grounding pin to the plug of the 220V version of the roaster would mean that we could use the same single layer as in the UL standard. So now all 220V versions will have a plug with a grounding pin.

TIP TEST

This test is a great example of both the differences between the two standards and the differences between the theoretical design on the computer and how things react in real life. For UL, the roaster must be able to sit on a 10-degree incline, fully loaded with beans, without tipping over, which we passed without issues. IEC requires that Kelvin sit on a 15-degree incline, without any beans, without tipping over, which it looked like we would pass when we analyzed our CAD, but because of the differences between CAD and the real thing, fell just short of, by just one degree. That leaves us with two options.The first is to make an expensive and time consuming tooling change to the base of the roaster. The second option is to test the roaster while it is laying on its side and make sure the roaster doesn’t get too hot while in that position. We are taking this second approach and have already modified the software and safety systems to ensure we can pass that test.

MISUSE TEST

One big test that is still ongoing is what is known as the Misuse test. This is to ensure that the roaster is safe even in extreme conditions. They run the roaster on full power for as long as they can, and then when the cooling cycle starts, they shut the roaster down and start it again on full time and full power. They do this for several hours, getting the machine as hot as they can until it reaches a steady temperature. During this test, they monitor the temperatures on several external surfaces, and they aren't allowed to increase above a certain threshold. It is during this test that we are having some issues. The tricky part is ensuring that we can pass this test while still ensuring that users who may have a lower voltage coming from their wall can still get a nice dark French or espresso roast if they want. We are currently tweaking our software and are anticipating sending new machines to UL/IEC in the next week as the final step in the safety testing.

As we mentioned in the intro, for a timeline moving forward, our team is working on all ends to make these necessary adjustments to pass our UL/IEC testing. As soon as testing is finished, we will release an update which will include a more firm timeline with specific dates of when to expect your roaster to be delivered. We’re as close as we’ve ever been to bringing Kelvin to your countertop and are thankful for your support on this journey.

INITIAL GREEN BEAN LINEUP

Since our last update, we have hit the milestone of finalizing our initial green bean offering! As you might recall from taking your Backerkit survey, we previously asked you what your preferred roasted coffee flavor profiles were. Based on your responses, our team has worked closely with our bean suppliers to narrow down the best beans that we believe will match your roast preferences. Not only do we feel that this selection of beans fits well with Kelvin, but that our lineup will provide a variety of options for our customers to experiment and experience the range of flavors fresh roasting can produce. Listed below are the beans, as well as their country of origin. We’ll be releasing additional information on each bean in future posts, stay tuned!

#1 Tuxpal Select: El Salvador

#2 Santa Ana Natural: El Salvador

#3 San Jeronimo Miramar Catui: Guatemala

#4 Ceiba: Guatemala

#5 Huila Acevedo: Colombia

#6 Supremo: Colombia

For our initial shipment, we will distribute our green beans across our pre-orders. If you’re craving more choice in the beans you receive, don’t worry! After our initial pre-order fulfillment, we will be listing all flavor profiles on our website and will offer single-order and subscriptions so you’ll always have fresh curated green beans available for delivery to your door.

Also, just because we do not carry beans from a certain origin country at the moment, it doesn’t mean that we won’t carry them in the future. We are constantly looking for ways to grow, and plan on expanding our green bean selection even more down the road. Let us know if the comments if there is a specific green bean you would like us to feature as we build out our selection!

Lastly, we want to remind you that if you need to update your shipping address or payment method, please do so ASAP. As always, let us know if you have any questions by sending us a direct message, or emailing us at [email protected].

Best,

Team Kelvin

Production Update from China
about 5 years ago – Fri, Aug 02, 2019 at 02:14:34 AM

Hello Backers,

Members of the Kelvin team recently returned from visiting our manufacturer in Shenzhen, China. We have some exciting updates to share on the manufacturing progress!

Functional Updates

One of the primary reasons for our visit was to finalize the user interface flow. When you turn on your Kelvin Roaster, you will set the initial roast time and heat level. You can set the time anywhere from 1 to 20 minutes and the heat on one of 7 settings: LO, 5, 6, 7, 8, 9, 10, HI. The heat level is not an explicit temperature because the temperature of the air within the roast chamber depends on many factors (how many beans are in the roast chamber, how long the roaster has been running, the line voltage of the outlet in your kitchen, ambient temperature, and others), so we opted for a simpler scale for heat level.

Both the time and heat level can be adjusted during the roast cycle, although the roaster is limited to 20 minutes max roasting time. The default setting is 8:00 minutes at heat level 8. Users may want to roast for shorter/longer and/or at a lower/higher heat depending on your roast quantity and desired end point (light/medium/dark),  but the default settings will give you a good baseline for experimentation.

Once the roast cycle has finished, a cooling cycle starts. The minimum cooling cycle is 8 minutes to ensure that both beans and the roaster itself have had enough time to cool. Users may find they want to run the cooling cycle longer - you can always add more time to the cooling cycle if you wish, but for safety reasons you cannot make it less than 8 minutes.

Aesthetics Updates

Another part of our trip to China was to examine the pilot production parts and make sure that the Kelvin Roaster meets our standards for fit and finish. This includes things like making sure the foil stamp logo on the front of the roaster matches the color of the other copper parts, determining what level of visual variances are acceptable, and even what custom marks on the top handle and inner glass chamber look like. For example, we ended up requiring a custom foil for the logo mark on the base housing (see image below). This required additional investment from our team, but we want to make sure all components are as close as possible to meeting our high standards. 

Next Steps

Roasters have been sent to UL for the functional testing portion of the certification process. Throughout the process, our team will receive periodic updates – we will keep you up to date as we go through the process!

As a friendly reminder, if you need to update your address or make a change to your order, be sure to send us a Kickstarter message, or send us an email at [email protected] and we would be happy to help!

Best,

Team Kelvin

Workstreams Happening Behind the Scenes
about 5 years ago – Tue, Jul 16, 2019 at 01:50:13 AM

Hello backers,

Before we jump into updates on some behind the scenes workstreams, we wanted to share a manufacturing update. Our team is currently in Shenzhen, China to approve all aesthetics and functional components of the Kelvin Home Coffee Roaster. The team has been documenting the trip and we will share a full report soon. This is another exciting milestone for the team as the next step is to send units for rigorous testing at UL. We’ve mentioned UL testing in prior posts; this is an important step to ensure product safety and quality. 

Today’s post focuses on the project workstreams happening behind the scenes — our pre-order platform, e-commerce website, and green bean subscription program. 

Over the past 6 months, our designers and developers have been working on a new look and feel for our e-commerce platform that allows users to purchase the Kelvin Home Coffee Roaster and green beans to accompany their Kelvin order. For users who prefer a “set it and forget it” approach, the platform also supports subscriptions for ongoing delivery of green beans right to your door so you’re always ready to roast.

As we were hard at work and approaching the launch of the new site, we received the news that our subscription platform, Lemonstand, had been purchased by MailChimp and was shutting down in a matter of weeks. As we communicated previously, our team quickly pivoted and devised a plan to salvage what we could to re-build on the Shopify platform. Currently, we are in-progress on that migration.

A few weeks following, we learned that our pre-order platform to process and track pre-orders was shutting down after being acquired by Indiegogo. Again, our designers and development team quickly researched and mapped a plan to migrate to a new provider. We launched this new platform a few weeks ago. Customers who purchased a Kelvin Home Coffee Roaster outside of the Kickstarter platform prior to June 5, 2019 should have received an email about this migration (please email us if you haven’t!).

The team continues to demonstrate resilience and quick thinking as we learned of these platform setbacks: assessing options, then mapping out a plan that keeps you, our backers, top of mind. 

In the fall, customers will see a new e-commerce platform launch to allow customers options to both purchase individual quantities of green beans or to setup subscriptions for ongoing delivery directly to your door!

Looking forward to sharing our next update on the team visit to the factory in China! 

Best,

Team Kelvin

Progress Update + BONUS FEATURE!
about 5 years ago – Fri, Jun 21, 2019 at 12:57:51 AM

Hello Backers,

It’s been a little while since our last update and, boy, have we been busy! Our team has been working diligently to bring you the best Kelvin experience  — from roaster manufacturing and digital platform to green bean sourcing and roast/taste testing. We appreciate your patience and value you as our loyal Kelvin community.

Production Timeline Update

As we mentioned in our last post, one of the critical paths for manufacturing is the completion of UL evaluation and testing. We received the initial report from our construction review and there were only a few minor items to address. Our manufacturing partner is moving along on those fixes while the final programming of the electronics is being completed to implement our new control interface (more on that below). Once these items are complete, UL will begin functional testing and evaluation.

With these updates considered, and assuming there are no major findings from UL functional testing, the current estimate for shipping is mid-to-late September. This is obviously later than we hoped, but the results are a higher quality and a safer product. We’ve been sharing our latest production samples with some professional roasters in Chicago and the feedback has been very positive, so the finished product will be worth the wait!

Bonus Feature!

As a thank you to our loyal community for your patience, we’ve made the effort to add an exciting bonus feature — Kelvin now has temperature control! 

While we’ve been working out the final production details, we had the opportunity to implement this new feature and we’re thrilled to share it. The temperature control will provide additional functionality to allow users deeper exploration when roasting coffee. For users that simply want to get roasting right out of the box, we’ve also developed an intuitive preset to guide your roasting experience. 

Next Steps

Our team is headed back to China in 3 weeks for final production approvals! The production approvals are a major milestone in our manufacturing workstream. This milestone means we can move forward with a pilot run of 50 units, and complete the UL functional testing and evaluation. 

We have some other updates we’ll share soon about the digital platform and green bean sourcing. Stay tuned!

Thanks again to all of our backers and pre-order customers. Without your support, we wouldn’t have been able to make Kelvin a reality. 

Best,

Team Kelvin