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A 0.80mm thin flexible wristwatch with an E Ink display housed in a single piece of stainless steel.
7,658 backers pledged $1,026,292 to help bring this project to life.

Recent updates


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We are shipping


Hello Backers,

Last week, we worked with our manufacturer to finish building, testing, and shipping our first batch of products!

We'd like to share a few photos of this final process:

Final Testing:

Ready for packing:

 Scanning base station serial numbers:

Boxing up:

 Ready for delivery:

We are delighted with how the product has turned out and are excited to be getting them onto your hands.

At this stage we are being careful to start slow to make sure our process has all of the kinks worked out of it.  For those of you who are curious how we are going about the shipping queue, we are shipping by both order number and the SKU that we are currently producing.  We have started with the black, raw titanium, medium watches for this shipment, but will be changing the line over to cover the different color and sizes in subsequent orders.

Now would be a good time to make sure your address is correct in the Kickstarter system.  If you are unfamiliar with how to update your address, we wrote a brief tutorial here:

Thanks again for the patience and and support.

-Jerry & Dave | CST

Progress Update


 Hello Backers,

We are back from another couple of trips out to the manufacturer and have some progress to share with you.  

New Steel Tools and Cavities

We found that some of the yield issues we brought up in the last update were due to a tool in our molding machine flexing.  We modified the molding process and made a new tool from steel that does not flex, so all of the units show much more consistency than previously.

The photos at the top of this post are from encapsulation tests we have been running.  We are currently addressing some issues we are seeing with the encapsulant on the small size units and running bending stress testing to make sure it does not have any issues before we ship the product.  These tests are currently in progress.

The Batteries

We have a documented test procedure, and have tested a batch of batteries with this procedure to make sure the batteries we use are good and mechanically sound.  Dave personally inspected the batteries that pass this test and found a small subset of the batteries seem questionable.  We are waiting to hear back from the battery manufacturer for their recommendation on how to resolve the issue.

The Bands

The issues with the bands look like they are becoming resolved.  We have received a batch of bands from the manufacturer and while we currently need to test every unit to determine whether it meets spec, we are seeing that we are getting a good yield of bands and should be able to get to 100% in spec in time.

Moving Forward

The last two hurdles are making sure the units pass bend testing and resolving the battery issues. Once we are past this, our plan is to start getting these out the door to you.  

Once again, we were delaying the update until we could say "we started shipping!" since it looked like it would be just a week or two out for the last few weeks.  We apologize that our update cadence is slower than many of you would prefer, so we will be revising our approach to keep you informed irregardless of whether the milestone we anticipated was met.  We will be back visiting the manufacturer again next week and we will post a brief update after that trip as well.

Thank you all again for your patience and support.  

-Dave, Jerry & the CST Team

Progress Update


The first samples made with all final manufacturing processes:

We just returned from another 2 week trip to California to work closely with our manufacturing partner.  Above are the first units produced with 100% of the parts and processes that will be used in final manufacturing and they look great!  The issues that remain are the bands, batteries and yield targets which we'll dive into below.

The Batteries

As we started to assemble our test units, we found that the batteries have some issues where some units have tabs that aren’t well adhered. The good news is that the battery supplier is extremely proactive in fixing the issue and we are working closely with them to document a testing procedure to weed out and replace problematic units. 

Close-up showing a tab not well adhered

Dialing in the Process and Increasing Yield

Throughout this journey, our bill of materials has increased. From issues with E Ink displays, the original battery partner closing shop, and the move to Nitinol bands has left us with very little room for scrapping parts that don’t come off the line perfectly. With sample in-spec bands, we were able to assemble 7 working units. However, this was from a batch of 16 circuits. The main reason for the low yield is due to the aforementioned battery tab issue. We are addressing the issues in order to get the yield back to a reasonable number before we can pull the trigger on high volume manufacturing. 

The Bands

We’ve been working for weeks to get a schedule from the supplier for when we will be receiving bands in California. Delivery dates and quantities were in a state of flux, so we had been waiting to update until we had parts in-hand. Unfortunately, as of right now, the bands have still not arrived. 

So, what’s been happening?  At the point we approved the first article parts we were told that 200 parts a day was a safe estimate of what would be produced.  It took us several weeks to track down why we were not receiving parts as promised. It appears as though the supplier was having some challenges meeting that estimate due to machining tolerance creating a lot of ‘scrap’ parts that were outside specification. It turned out that the bands were not being measured according to our instructions, so many “scrap” parts were actually good, we also looked at their measurements and found ways to loosen tolerances without impacting the design in order to help them reach yield targets. 

As of yesterday 200 in-spec bands were due on the loading dock in California, but we just received a note that the 200 units that were supposed to ship were not shipped since the vendor had missed a process step (cleaning) and the parts were out of spec, so they were returned to the vendor. 

Our manufacturing partner has installed daily updates and check ins and have also mobilized a team to be at the band manufacturing site to oversee production in order to resolve the issues in getting these made. We will continue to update you as we get more information about the shipment. 

The cautious approach and the careful delivery schedule from the supplier is likely due to the following reasons: 

-The raw material costs for Nitinol sheet is incredibly high, running ‘failed parts’ and rushing them through the line is a costly error, running them slowly will get the supplier a better yield and less scrap parts...ultimately they will get more ‘good’ parts that pass inspection that we have paid for. 

-In ‘mass manufacturing’ it would be normal to run 2,000 or so parts through the line to check and measure them to make sure consistency was reached, in our world that would be around $50,000-$100,000 in parts to ‘check’ the system..or roughly 10% of all backing Kickstarter backing money to ‘check’ the system. 

-Internal systems are in place that check FAI (first article parts) and lead to PPAP (Production part approval process) these processes are internal to the supplier and it has taken sometime for those internal processes to be opened up to us in order for us to successfully collaborate on arriving at a solution. This supplier has invested a lot of time and effort so far in getting these processes fine tuned. 

-Chinese “Golden Week” was the 1st of October to the 7th of October, this means the lines ramped down and came back up upon return.

We have been hand assembling circuits to bands and continue to refine and prepare all the other steps of the process for the arrival of these bands. Fingers crossed we will be receiving these bands at 1,000 to 2,000 units per week, meaning about a month of production time.

Moving Forward 

Having two people at CST handle the design, packaging, engineering, CAD, process development and documentation for a product has been quite a handful. In some ways this has been good for us allowing us to weather these numerous delays by staying small, but it also means that sometimes communication suffers and we apologize for this. The manufacturing partner is now providing more support to get us across the finish line and dial in these details to increase yield. We are systematically addressing these last few issues around yield and the bands. We understand that you are anxious to get the watches and we cannot wait to get these out to you too!

- Dave, Jerry and the CST team

Nitinol Bands | Golden Samples Received.


We received the fourth round of sample bands today from our metal partner and are happy to communicate that everything is looking right on for the dimensions. 

We have checked these here in Chicago and will compare notes with the manufacturer in the next day or so when the factory returns to work after observing a lunar holiday. At that point, we’ll give clearance to get the production lines going for these parts. 

Below, you’ll find a quick dimensional survey completed on these samples. Our measuring equipment has an approximate tolerance of plus or minus 0.005mm for thickness, and plus or minus 0.01mm for those “interior” dimensions which are less critical. (Basically, the spreadsheet and the parts prove that everything will now fit). 

In summary, this is looking MUCH better.

Checking the bands dimensions
Checking the bands dimensions

Band Update and Assembly Step Refinement


Communication Lapse 

First off, we know we need to do a better job communicating and apologize for the lapse. We thought that if we just put 100% of our effort into kicking off shipping that this update would read “We started shipping!” and this would answer about 95% of your questions and e-mails. We want to make sure it's known that we are not going anywhere and are committed to getting you your rewards as quickly as possible.  The reason that we usually prefer bigger updates is that if we publish an update with lacking information, it actually increases the amount of questions we get instead of the intended result of decreasing inbound questions.  We know that we need to provide you a better "heartbeat" to make sure we're still working, so we will do better at providing this moving forward.

Wrestling Nitinol Bands Into Mass Production

The nitinol bands are the key part that is holding up the entire project plan. We know that many of you are frustrated with these delays and so are we. It’s been about 5 months since we received the first nitinol sample band. We have been through 3 sample rounds with the supplier, each round taking a more time to produce and receive than anticipated. Never has it been clearer that the tolerances we are attempting to hold and the thickness goal we aim to achieve is something that is very unique compared with more routine requests in manufacturing. Each round presented it’s own type of quality control problems. The first round were simply not thin enough, the second round were almost thin enough but had the incorrect surface finish, the third round, although thin enough, had major tolerance oversights in the other dimensions, meaning the flexible circuit module would not fit within the pocket. With much discussion on how we could work with the bands as they were, we had to make the painful decision go through another round of samples to get the parts right. We are ASSURED by Flextronics and the supplier that these will have none of the previous issues presented in the prior rounds of samples. Flextronics are shoulder to shoulder with us and are as surprised as we are that this has taken so long to dial in. Daily late night calls, passionate debates, the creation of incredibly detailed quality control documents, tighter and tighter tolerance definition, fabrication of measurement tools and fixtures have helped isolate and solve the problems we were seeing. Here are some images of one of the measuring devices that has to be used directly after the forming process, there is an 18 page document associated with all dimensions and tolerances that each and every band must pass to be correct for the final product. 

We are poised to receive that 4th (and, again we are assured, final round) of what are called ‘golden samples’ within the next few days. These were planned to ship on August 31st, but have been delayed and finally shipped out on September 3rd.

With shipping times and customs these should be in our hands September 8th or 9th. Once approved we should then receive large orders of these parts over the following weeks. The nitinol manufacturing partner can supply 200 bands a day for the first week or so then 400 a day as they refine the process. it should mean that we’ll be staggering our ship out to all of you as we receive those parts, rather than waiting for them all to be completed. 

Other Activities

We just finished a trip to California where we continued to tune circuit encapsulation, color and hard coating to increase quality and yield.  We want to make sure we are managing all the different process so that we get a high yield of usable sub-assemblies. We’ve also been analyzing other parts of the assembly process and refining those to increase output per day in preparation for the roughly 2000 bands that should be arriving each week. 

After printing 

 Die cutting

 Jig for assembling modules to bands

Inspecting die cut fit

Next week at TechCrunch

We will have a few demo units assembled onto some of the sample bands we received on display from Monday 9/8 to Wednesday 9/10 as part of the Flextronics Lab IX booth at TechCrunch Disrupt in San Francisco. Dave will be manning the booth most of the time, so if you are around come say hi!


As far as a new ship date, we are faced with the challenge of whether we give you the date we expect, as we have been doing (which means we assume that no more unexpected delays come in to us) or do we assume that another new delay of some sort is bound to occur and give you a safer date. If we play the safe route, many of you will ask why it is so far away, and the answer would be “we don’t know, because we are accounting for the unknown”. That said, we have no information that would point to further significant delays after we get these bands. There will be a “ramp-up” period where the quantities of units out the door has not yet gotten to the pace we eventually will get to, but we should be able to start getting these out the door in the coming few weeks.

Thanks again to everyone for their support and patience during this process.  We are looking forward to getting these to you as soon as we can!

Dave, Jerry and the CST Team.