A Plastic Tamper?
December 02, 2016
I've had a number of barista tools and products rolling around my head for a while and the time has come to start making them a reality. The first was evidently a re-think of the humble tamper. This post is an explanation of the rationale behind that tamper: a detailed look at every decision that was made, and why I made it.
A while back I released the Pergtamp. Luckily, the improvements it brought were more valuable than the name. It sported a sharp edge that increased the total tamping area, increasing extraction yield by up to 2%. It was also nicely made and looked pretty.
Unfortunately there were some downsides:
- I was acting as a middle man to a middle man, blowing out the already high price for a premium Australian made product.
- The base was a lump of extra-expensive hardened stainless steel machined in a difficult way.
- If the sharp edge was damaged by drops or knocks its diameter would change, rendering the tamper unusable in snug fitting baskets.
Less than ideal, so here’s what I did about it.
There’s two options with product design. Make it indestructible, or make it replaceable. Until now, every good tamper base has attempted the former. Unfortunately Baristas drop tampers and they get damaged. Even the hardest steel will become deformed over time.
The only thing a base has to do is be circular and have a flat bottom. It doesn’t have to be thick. It doesn’t have to be heavy. And if it’s not lasting forever, reducing the cost of replacement is ideal. So I made it 1mm thick. This means a replacement will be US$15 instead of >$60.
What materials does a tamper really need to be made from? For the very bottom tamping face, we need food safety compliance, durability, and smoothness. Polished stainless steel is the obvious choice here.
For the handle, we need nothing more than excellent grip. Here I chose Acetal, or “Delrin”. It’s a high performance plastic commonly used to replace metal parts. It’s strong, durable, and food safe. When sandblasted it has a wonderful tactility that can only be described as the hardness of stone combined with the warmth of wood. It’s truly bizarre, and most people can’t stop themselves from holding and rubbing it. The last thing this handle feels like is a cheap plasticky gimmick.
Both handle and base are machined from solid rod stock with incredibly precise CNC machines.
Scalpel, not axe.
Does a tamper have to weigh as much as a paperweight? No. There’s absolutely no need for a tamper to be heavy except, perhaps, to massage ego.
After using a light tamper for 10 minutes it feels completely normal. Going back to a heavy tamper feels like you’re picking up an axe. It’s cumbersome and inaccurate. I chose to save on shipping costs, materials, and the repetitive strain on our bodies.
Most tampers are at least 3 parts. The base, the handle, and the screw to connect them. The join between these two parts is at the thinnest point which means you can use thinner stock for the handle and save some money.
Unfortunately it means the weakest point is also the thinnest.
The thin base allowed for two major improvements.
- I could form the entire handle out of one piece of material. No joins, no seams, no glue.
- The screw could be deleted. Instead of a 10mm wide threaded screw, I could have a robust 30mm thread that’s also made from the same piece of metal as the base. Fewer parts, and less chance of breakage.
*The Acetal handle should survive anything short of an espresso machine being dropped on top of it. Even then you’d be lucky to break it.
The original Pergtamp had slanted sides to allow for “nutating”. The serendipitous side effect of this was the elimination of the vacuum effect; that annoying thing where the puck is ruptured if you pull the tamper out too quickly.
Now that I’m fairly certain nutation is a bad idea (my apology article here) I could go back to a handle that closely matches the diameter of the basket. This lets you check the levelness of the tamp quite quickly. The v shaped groove between the base and top slope of the handle allows for both vacuum elimination and the quick level check.
Cleanliness is next to godliness. If your tamper is getting dirty then the only question that should be asked is: why was your hand dirty? White is clean, and bold, and has an absolutely gorgeous alien-like glow with this material.
Shape is also a big deal. I went through a wide range of shapes and styles before settling on this design. These are just some of the prototypes I created. Many more saw the bin during frustration!
I wanted a handle that sat right in the middle of most common sizes. Not too big for small hands, not too small for large hands. Interestingly the most important dimension here was the width of the top end. Of course one size cannot fit all, so I’ll be releasing a smaller handle early next year.
This Barista Hustle equipment concept is open and flexible. Manufacturing is a whole new world for me and my eyes are wide open. I’d love to hear feedback, ideas, and criticisms about the things I design so they can continuously improve. Black is coming. Premium materials are coming. More flexible laser engraving on smaller orders is coming.
The preorder campaign is still open, with a bonus of free shipping worldwide. Initial response was so overwhelming that I doubled the first order. There’s plenty more! Head here to put your name down for one. With the christmas rush crippling shipping and fulfilment services around the world I’m pessimistic about a 2016 delivery, but am still trying!
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