With your help we've been able to finalize Handground's design for manufacturing and are beginning the tool making process. Here are the results from the last survey, along with an update on engineering and a new timeline for delivery.
The staggered marks took over 50% of the total vote and will be screen printed on the side of the hopper. The number of the marks on the final product may vary to reach an incremental level that is easy to remember/count. Ex increments of 10 grams
There are three tabs (like the ones pictured above) molded on the inside of the hopper. The top cap locks on by sliding over these tabs when you twist it onto the hopper. We were concerned that the bump on the bottom of the tab in the old design may wear down and stop holding the top cap in place over time.
The new design has a sloped bottom that tightens to the top cap at about 2/3rds the length of the tab. If the plastic starts to wear down over time the top cap will cover more of the tab but the slope on the tab will cause the top to always tighten.
This is the winning combination of cut + laser engraving for the bamboo filter rack. We have requested one final sample from the factory with this new design and will then begin production.
In another effort to improve the longevity and precision of Handground, brass bushings have been added to support the horizontal and vertical axles. The bushings will be molded into the plastic pieces that support the axles.
Brass bushings can achieve a tighter tolerance than plastic, will reduce friction and increase the lifespan of the device.
The image on the left shows an example of the yellow brass bushing molded into the clear plastic of the hopper. Brass is an ideal material for this application because it is self lubricating and has low friction when in contact with other metals.
Our concern is that the yellow bushing may detract from the aesthetics of the grinder (when it's not filled with coffee beans). One solution that we are looking at is "white brass" which looks similar to the stainless steel axle. The problem is that white brass is very hard to find and the cost is approximately 6X. We will keep you updated as we learn more from our suppliers.
Our original plan was to use an existing 38mm ceramic burr mill. In the past few weeks we made a visit to the burr mill factory that produces burrs for several other brands of manual grinders and learned that the cost to create tooling for a custom burr is not prohibitively expensive.
Since the burr mill is the central component in Handground, we jumped at the opportunity to improve it. We are now working with the factory engineers to produce a larger mill that takes advantage of Handground's size and configuration.
If you took the survey, the option of filling the Handground outline with coffee related items won the vote. We will shape the design outline around this concept for the next design competition. For the back of the shirt, the Handground logo and icon placed high center were the top choices.
Sometimes you stumble onto something and it seems too good to be true. We found Domestic Stencil Works on Barista Magazine's Instagram and learned that they make ink for T-shirts out of spent coffee grounds! We will include this as an option for the T-shirt in the next survey, I hope you're as excited about this idea as we are.
The only catch is the ink only comes in one color. Coffee
The polished aluminum handle looks great and the die cast process gives it a solid weight. The knob shown here is made from Pakka wood which is created using intense heat and pressure to fuse multiple layers of treated hardwoods into a beautiful, durable and moisture resistant composite.
In the latest prototype we were able to fit 15 coarseness adjustment steps without the setting skipping while the grinder is in use. Our goal is to have each twist produce a combination of sound, tactile feedback, and visual confirmation between each coarseness level.
We will continue to experiment with different spring strengths and slope angles on the steps as we move into full production.
The new gearbox has shown significant improvement over previous versions. Brass bushings now support the horizontal axle that extends over the vertical gear and connects to the handle.
The vertical axle no longer slides up through the vertical gear as the coarseness adjustment changes. Instead, the gear is fixed to an axle that is mounted on a bearing and held stable. The vertical axle uses a spline and keyhole to connect beneath the top cap.
We have deliberately not shown pictures of how the gear box is configured because this has proven to be one of the most difficult aspects of this design. We will continue to test this design to look for signs of premature wear.
At this stage we are confident in moving forward with the tool making process. The design has been finalized for manufacturing and our tool maker will begin the process of forming blocks of metal into molds for the plastic injection, die cast and glass processes.
Fun Fact: Handground is made from over 30 individual parts consisting of 9 different types of material.
We have spent a considerable amount of additional time and resources towards improving the design and the investment was worth it. Every part of the Handground design is now superior compared to where it was during Kickstarter.
The cost of improving the design is that we are now behind schedule for our estimated delivery date. Our initial projections estimated that the design for manufacturing phase and tool making process would be finished by May.
We are beginning tool making now which can take up to 60 days. After the tooling is finished we will produce a "first shots" run. It is common that changes need to be made to the tooling at first so we are accounting for 30 days here before production begins.
Once the tooling is dialed in it will take approximately 30-45 days for the first batch to be made and then an additional 30 days to ship from Shanghai to Los Angeles. This timeline would put the Handground delivery date at mid Nov to early Dec.
Brandon and I have been working with the Platform88 manufacturing team in Shanghai every day for the last two weeks. We are doing everything in our power to build an excellent product as fast as possible and will look for opportunities to accelerate the delivery deadline.