Start by making delicious bolognese sauce for dinner, but wait don't throw out that tomato can!! Save it, reuse it.
Find a bolt in the garage that will span the diameter of the can. (Mine was 3/8, you want it strong enough for some good wacking).
The bolt had threads the whole length and I didn't want to mar the top of my porta filter...
Wait, look at the brass tube I just found, it fits perfectly on my bolt!!
Voila, done and done!!
Cheapest knockout box on Amazon is over $20, this was free!!
An upgrade would be to decorate the can, or make a wood box to surround the can... Your suggestions below!!

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About This Instructable




Bio: noahthomas.org I teach sculpture and design, and make and show my own sculpture. Check out my website:
More by nthomas12:Anvil Restoration and Hardening Esspresso Knockout Box Fix An Old Wooden Ladder For Less Than $10 
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