Delivery Timeline Update Dec 8th, 2017





Today is a memorable day in Mellow history. Today we can proudly announce that all (savor this slowly: A-L-L-!) of the 2017 deliveries have been boxed, labelled and shipped. It’s been an extremely exhausting year, but now it’s done. The pre-orders of 2017 are out. Mission completed!

Thank you guys for your endless patience and support. And finally a big up to our own crew! These guys and girls who toiled through all the unexpected hiccups, curve balls and speed wobbles have earned themselves a big fat Mellow medal for life (and a schnaps on the house).





Current Pre-Order Delivery Status

All 2017 deliveries up to order #2017010462 have left the building. Please note that for international orders the completion of the shipping process might stretch into next week. Although we can report that this week UPS managed to deliver within 24-48 hours – to America, Asia and even Australia.

All orders that have been placed after the 31. October 2017 will be shipped next season from March 2018 as stated on our website.

March 2017 - First delivery batch to Kickstarter backer #46.



May 2017 - Second delivery batch,to Kickstarter backer #107.



June 2017 - Third delivery batch to Kickstarter backer #166.



July 2017 - Due to a cyber attack at the shipping provider TNT international deliveries came to a standstill. European deliveries were severely compromised, but we still managed to almost fulfill all European Kickstarter deliveries.



August 2017 - Kickstarter deliveries fulfilled. We found a solution for international deliveries.



September 2017 Pre-order deliveries have started in the second week of September. Until the end of the month boxes up to pre-order #394 have been sent out.



October 2017 We switched our fulfillment shipping provider to achieve a faster and more reliable delivery service worldwide.



November 2017 Battery production finally started rolling smoothly allowing us to pick up speed of deliveries



December 2017 This month is marked by two big milestones: The release of our first major firmware update activating the Endless Mode and finally the completion of all pending pre-orders. Hooooray!

What has been going on at Mellow

Over the past months, fans and supporters have been approaching us with the obvious question: What have you guys been doing for so long?!?

In order to be as transparent as possible we thought we take you on a little journey to the world of product development and provide some insights on why we are still not pumping out thousands of Mellow Drives.



Obviously we are not happy with the delays slowing our business down massively and creating huge unplanned costs to our company. Nevertheless we were able to find and overcome some major flaws that would have hurt us and possibly our customers in the future. By overcoming these we could ensure the very high quality level that we promised and that we want to continue delivering.

Here is a list of some of the issues we overcame on our way to series production.





The Motors

The biggest and most far-reaching event was our decision to change the motors while we were well in the middle of our development phase.

We found that the torque (turning force) we had anticipated in the beginning - which had became the basis of our further development - was insufficient to fulfill the needs of a high-end electric drive. What followed was a chain reaction that influenced literally every component of the electric drive system.

We increased torque by roughly doubling the magnetic material in the same space. We thus had to change from flat standard size magnets to custom-made arced magnets. Custom magnets are stock parts that are available quite quickly but in order to become motors with custom magnets we had to do the following:



1. Make drawings for magnets



2. Find and select a magnet manufacturer that has the capacity and time to react super-fast



3. The manufacturer has to order the magnet material, design and produce a mold for the magnets following the customer’s drawings.



4. After finishing the mold and receiving the magnet material sample pieces are made and sent to the motor manufacturer.



5. Instead of using the planned magnet carriers the magnets now had to be glued into a custom made steel ring that then was pressed into the rotor.



6. To make this process safe and reliable about a dozen different glue/surface treatment combinations had to be tested and evaluated.



7. Sample motors were made and send to us for measurement and evaluation.



8. Following release from our side, a large quantity of magnets was ordered, produced and shipped to our motor manufacturer



9. Our motor manufacturer had to introduce the magnet gluing process into our motor production line requiring new tools, process steps and fixtures.

This whole process cost us several months and lead to a flood of changes in other components.





The Power Electronics

As a change in the motors’ ability to build torque also requires changes to the power electronics, several iterations of improvement on the hardware were necessary to compensate for the additional power of the motors.

For example, we had to increase the allowed limits of current pushed through the board, thus requiring comprehensive adaption of all current measurements and hardware shutoff-circuits.

New sample circuit boards had to be produced, tested, verified and released for production again.

Energy Management

More powerful motors now pump about twice the energy of the original motors back into the system. This means we had to rework our energy management and braking-control algorithms as well as limiting safety functions and deratings.

These changes also introduced a load of brand new software features that further increase the safety and reliability of the Mellow Drive.

The Battery Housing

Our battery pack housing was so flame retardant that this made it difficult for the ultrasonic welding to properly bond the seam of the two halves of the outer shell. This could lead to the batteries falling out of the frame when a strong hit occurs and even braking of the welding seam altogether.

If this happens to you, stop riding and contact us right away. We found a solution for this problem and all batteries/Drives shipped here on in will be fine. We also will exchange all the batteries for the Kickstarters who already have received their Drive.





In order to overcome this weakness the injection molds had to be reworked, new samples were made, shipped, assembled to functional batteries, tested, approved and then production of the housings could start again.

The whole turnaround of a process like this was no less than 8 weeks, causing more delays for production.

The Battery Management System

Our custom battery management system (BMS) created a massive delay when we found that a conductor track on the printed circuit board (PCB) was damaged. 900 BMS boards were scraped and had to be manufactured again.

The supplier of these boards has always been a very reliable source for the PCBs and has worked with our battery supplier for years, but obviously they messed up on that batch. The flaw was found quite late because the conductor track was good enough to pass the initial check but then would break as soon as the first stronger vibrations occurred.





The Wheels

In order to fit the wheels properly to the motor we had anticipated to rework the existing cores of the injection mold as we showed in our Facebook live stream some weeks back.

Further measurements made it clear quickly that a simple rework of the cores was not going to do the trick sufficiently, so we decided to scrap the old injection tool and build a new one.



This was done on an extremely fast track thanks to a huge effort of our wheel supplier who did several rounds of adapting the tool, injecting, measuring and reworking again, until finally a perfect fit was achieved.





We also introduced an additional change to the urethane wheel molds in order to get rid of bubbles that continued to occur in the urethane pouring process.

Finally, we recently adapted the composition of the urethane to make the wheels more resistant to wear, tear and external heat.

The Frame

Early this year we introduced a change to the powder coating of the frame and hanger.

The old powder coat would get dirty extremely quick and was terribly hard to clean. So we had about 2000 frames coated with the new material which even our supplier thought was a good choice to do.

A few weeks back, the company that is responsible for gluing the plastic insert (the part that carries the main connector) into the frame really dropped the bomb on us by pulling out of the contract, citing too many problems with gluing the parts together. Since this is an absolutely high-end supplier that has proven its abilities in many projects with our production partners before, having them pull out was a very bad sign.

Finally, it was discovered that the new coating powder created a surface that wouldn’t accept the glue anymore, causing the plastic parts to fall out of the frame under the slightest shock.

In Drive assembly, the screws of the rear lid closing-off the electronics compartment were sufficient to crack the glue apart and void watertightness.

Half a dozen different industrial grade glues were tested without any success.

The breakthrough came late with a process where the surface gets treated with a special gas flame that takes away the layer of wax that would initially prohibit gluing.

A new supplier was found and production is going smoothly now, but valuable time was lost.





Heat shielding

Between the electronics of the Mellow Drive and the braking resistor lies a heat shield that protects the sensitive components from the heat created while braking. The magnet change described above continued to cascade, as it was discovered that the heat shield could melt due to the fact that after our motor change (see above) injects much, much more braking power back into the system.

On our standard braking test we could now melt the heat shield, which is not directly dangerous for the customer but the smell was not acceptable.

To overcome this, we got rid of the plastic heat shield and introduced a special material that can tolerate much higher temperatures.

But also here we had to locate suppliers, order samples, make tests, select a supplier, order the new parts, build a stamping tool to build and produce the new heatshields.

We are very fortunate that these issues are coming up early in production so the damage is still very limited and all of our customers can profit from the improvements.

As you can see, a lot of the issues that came up will now result in a solid improvement of the product you will receive.





Production Ramp-Up and First Deliveries

High quality doesn't mean that we can do no wrong, simply that we won't stop until we give the best of what we can do.

Although initial deliveries of the Mellow Drive brought the Endless Ride to five different continents, this also meant that our intrepid early customers represented a world of new ways and roads to challenge it. As they say, not even beta testing can replace real-world hard knocks.

The first issue to appear was the recently added speed safety lock refusing to disengage, keeping all users at Eco Mode speeds (25 km/h). Exotic locales, such as Senegal, meant that the blistering heat (44 C/111 F) and even hotter ground literally cooked the urethane, causing them to soften.





We stopped further shipping until new firmware / a software update for the first backers and wheel formula could be developed, tested and included with future shipments. This meant more delays.

But finally, this first wave of deliveries also showed us that after overcoming the last quality issues we were ready to begin final ramp-up to large production numbers.



