Industrial - Bachelors

Grind Griddle

The Grind Griddle is a compact and lightweight device, used to efficiently separate chaff from grinds in a mess-free manner before brewing pour-over coffee. Designed to have a variable sieve size this product can cover a variety of grind sizes to better suit your task.


Coffee Silverskin (CS), also known as Chaff, is the protective layer surrounding coffee beans, residing between the husk and the bean itself. Following roasting, most of the CS is removed, but a crucial 2% of the bean’s weight remains, varying depending on the processing method. When Chaff is present during brewing, it can obscure the coffee’s essential flavour notes. Conventional methods for its removal are often messy, and ineffective, typically managing to extract only 10% of the total 2%.

Chaff either weakens a coffee’s flavour or it imparts a paper taste to it

Lance Hedrick, 2019/2020 US Brewer’s CUp Championship Podium Placer

THe Problem

In the eyes of a brewer, smooth workflow is the key to consistent brewing, decreasing the chances of subtle changes within the chosen bean. That workflow is halted when CS is present in the grinds, requiring brewers to remove it using slow, inefficient methods.

Currently, the main methods for removing chaff rely heavily on blowing any visible particles of CS out of grinds, leading to the work area being covered in chaff. This method takes up to a minute of time and only removes a small percentage of the present CS, which ends up just wasting time. Another method is to grind in a large setting, meticulously remove through blowing or picking out with tweezers, and then regrinding. Although this method is more thorough it removes large quantities of chaff effectively, the only issue is it takes as long as brewing the coffee as well as leaving a mess behind.

Despite having numerous methods to remove chaff, the overall results are inconsistent and affect the workflow of the brewers, leading to inconsistent brew results and wasted time. When this was investigated it led to the majority of the surveyed users encountering chaff, but not bothering to remove it due to the hassle.

Brewers don’t Remove Silverskin due to the hassle and Mess


A literature review of the background of specialty coffee uncovered the methods used to process from fruit to roasted beans, as well as some insight into how chaff affects the overall quality of filter coffee.

Primary research was completed through a combination of qualitative and quantitative research methods, which was the chosen research methodology for this project. 29 participants completed an online survey outlining their experience with pour-over coffee and any areas that could require improvement. Three expert interviews were done to investigate how workflow and chaff affect each other in a cafe setting, as well as ask their thoughts on a potential device helping to aid in chaff removal. An observation in a current specialty coffee cafe was also done to analyse any small details done by the barista.

Each method of research including the background for coffee processing will be available in the Research Report (Link Below).

Research Report

Filter Coffee and the Workflow Caveats
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7 MB
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The Solution

This compact and lightweight device, made of BPA-free Trogamid Plastic for a frosted finish, efficiently separates chaff from grinds pre-brew. The unique design features a rounded base for easy back-and-forth agitation, which can be replaced when needed. You are able to shake it to sieve if you prefer to do so.

The sieve housing utilizes two hexagonal sieves with a 2mm diameter, offering adaptability for both large and small grind sizes, with a pull tab. Thanks to neodymium magnets, all components
snap together seamlessly, ensuring a satisfying user experience. Strategic chamfers add comfort in use and ease when pouring grinds. The catch cup features an elevated ridge that aids in breaking up sifted grinds, enhancing overall consistency. Simply detach the top housing and sieves from the catch cup to remove the chaff, leaving clean grinds for your brewer.

This tool enhances workflow, reduces chaff, and remains compact and portable for mess-free use.


Adjustable Sieves

The adjustable sieve requires the user to push/pull the tab to a desired point aligning the two sieves to the required size of the grounds. The sieve follows a hexagonal array to maximise the surface area required to sieve, whilst achieving certain adjustability.

Rounded Base

The rounded base allows the user to agitate the Grind Griddle with two hands rotating back and forth to sieve the grinds and separate the chaff. The base is hard-wearing and can be replaced through a friction fit when required.


The Grind Griddle design uses nine parts all up, with the catch cup and top housing being made of a BPA-free Trogamid Plastic giving it the frosted look. The sieves are fabricated from 1mm thick stainless steel and the rest is injection moulded from HDPE. Each major part is secured tightly through small 2mm diameter neodymium magnets which gives satisfaction with every use.

Robert Bailey

Rob is an Industrial Designer enhancing his views and ideas with his second degree Mechanical Engineering. He finds a passion in innovating with existing and new concepts, whilst problem-solving to discover real-world solutions. In his spare time, he has a love for making pour-over coffee and climbing.