Thanks for your continued support and thank you to everyone who gave us their feedback and voted for their preferences with regard to the LCD screen interface from our last update.
Following our last update, we have made great advancements in the development of The Porta Presso.
Since our last update, we incorporated in the ability for the user to adjust The Porta Presso grinder settings to adjust the size of the grinds. As with any coffee grinder, over its lifespan, it will eventually wear with use. By being able to adjust the grind settings it will allow users to simply adjust the settings slightly, making the grinds finer if the grinder starts to wear instead of needing to fully replace the grinder.
The Porta Presso team have made vital progress with the portafilter basket height adjustment to allow it to seal off the tamp. We have redesigned the portafilter basket slide in order to achieve a better seal when straining the coffee grounds. This involves a manual tab that is pushed across when inserting the basket. This slide pulls the basket in the extra 5mm and then screws it up onto the seal. When removing you slide it back the other way and as you do it will release from the seal and force itself out 5mm for better grip to remove the basket easily. Not only does this design allow us to fully seal off the chamber to allow us to generate the pressure required but it also acts as a failsafe to ensure that the portafilter basket will never come out unintentionally.
The image below shows the two current manual adjustments of The Porta Presso. The coffee grind adjustment (top) and the seal adjustment (bottom). Please note: this is a rendered image for engineering purposes and is not an image of the final exterior aesthetic of The Porta Presso.
Everything needs to be sealed off efficiently to ensure that during the espresso brewing process the coffee is able to be abstracted at the optimal 9 bar of pressure. This has been an important phase of the development to ensure that the coffee produced is of high quality. To optimize this, we focused on the seal design for both the lip and ring seal around the portafilter basket along with the O-ring between the cup and cup collar to prevent any leakage.
We have also re-engineered The Porta Presso cam system which developed excessive wear during the previous tests. A new motor will replace this initial system, which was finalized before sending off the remaining parts to our prototype manufacturer. To house the new motor, we have expanded the backpack slightly. This is a better resemblance of what the final product will look like, and cut in from the top. This is subject to change, as this may be able to be scaled down with production materials.
After refining our designs, we had our updated parts manufactured and a new Porta Presso prototype created. The key parts in the new prototype have been machined in aluminium in order to withstand the operating conditions and allow us to conduct extensive testing.
Bellow a diagram of The Porta Presso's new test rig with both the valving and heating chamber external to the machine housing. This is to allow for a complete run-through of the brewing process but also giving us the ability to work on one component at a time allowing us to improve each aspect one by one. Once we are happy with the standard at which each individual element operates then we will work on incorporating these parts back into The Porta Presso housing.
All the parts for The Porta Presso prototype are now functioning and all aspects of the system work individually, we can successfully grind beans, boil water, extract coffee and froth milk. From here it is refining each element, inserting everything into The Porta Presso housing and then beginning our tooling/manufacturing process.
If you are interested in seeing video footage of some of The Porta Presso parts in action be sure to follow us on Instagram www.instagram.com/PortaPresso and like our Facebook page www.facebook.com/PortaPresso