I've just made a down-the-drain knockbox. I always put my spent grounds down the garbage disposal, so this seemed like a handy device, since my sink is right next to my machine.

I bought the standard "Modern Knock Box Bar" from WLL for 6 bucks, then picked up an ABS pipe adapter from the hardware store for a couple more. http://www.wholelattelove.com/wll/modern_bar.cfm#

The adapter is called 3" x 2" but OD on the big end is actually 4" - a perfect fit for the bar. I just drilled a couple 3/8" holes in the adapter and inserted the bar. The bar comes with a couple of rubber grommets, so I left them on the ends to snug up the fit.



I just drop it in the disposal opening and shoot a little rinse water over it when I'm finished with it.

Our town utilities newsletter asks citizens not to use the sink disposal "as a garbage can" because it puts an additional burden on the city's sewage treatment plant. This came up awhile back in Using a garbage disposal for coffee grounds ok? and I'm curious: Why don't you use the trash can or compost it?

Admittedly, sometimes when I'm pressed for time on cleanup, I use the disposal. But with lots of kids in the house and a forgetful resident barista, I avoid it if only because unpleasant surprises like spoons, forks, and portafilter baskets have been known to fall in.

Oh lord... now you're giving me guilt. We could make a pretty good case for why coffee is bad for us and bad for the environment if we start down that road... (think about how many times it makes us flush the toilet! )

As for clogging the drain, I've been putting coffee grounds down this particular drain for 18 years, and I haven't had a problem yet. I started doing it when my uncle, a fireman, said they always put grounds down the drain at the firehouse, and when they took the trap apart one day to salvage somebody's wedding ring, it was "the cleanest he'd ever seen" (he did remodeling on the side).

There are obviously things that do cause clogging (don't ever try artichoke leaves!) and I wouldn't dump in a whole bunch of coffee grounds at once, mainly because it would take so much water to wash it down, but this device is designed for a single puck, carried away by the water used to rinse the portafilter and shot glasses.
-Gary

Maybe the acids keep the drain clear?

My uncle did believe that the coffee actually had a cleaning effect on the pipes. Could have been the acidity. Or he could have been full of baloney, but hey, he was my beloved uncle. All I know is that my pipes are clean, which is more than I can say for my conscience...

It's just coffee grinds...it's not like you're dumping some toxic waste down there. I give my used pucks to the snails in the garden so they can play hockey in the afterlife

GDubs wrote:Oh lord... now you're giving me guilt. We could make a pretty good case for why coffee is bad for us and bad for the environment if we start down that road... (think about how many times it makes us flush the toilet! )

Some of us do think about how many times we flush the toilet! Here in the desert, we don't run the water for anything unless it is filling something or falling on something. Running the sink while you casually brush away at your teeth will earn you a smack and an admonishment to "Go back where you came from!" I empty my knockbox into my compost.

GDubs wrote:As for clogging the drain, I've been putting coffee grounds down this particular drain for 18 years, and I haven't had a problem yet. I started doing it when my uncle, a fireman, said they always put grounds down the drain at the firehouse

I dunno, I've been told, by the guy that repairs espresso kit around here, that the biggest part of his repair jobs as far as leaks are concerned, are overflowing driptrays because the drains are clogged with grounds. This is pro kit, too. OTOH, you can do what I've done at my girlfriends house, and fit that box into the lid on the garbage can. Keeps the dog out of the garbage, but allows easy access to smacking the puck out!