That will ruin them at $1,500 to $2,000 per litre of ink...

They could provide Starbucks branded ink of which 95% of the cost is licensing fees which they pay out tax-free to themselves.

They could scribble each customers name on the printouts with a sharpie

"Got a flat black and white parking ticket appeal form for Kim"

- Name?

- Sauron.

- Sharon it is.

Maybe they could do some R&D to see if coffee could be used as ink.

I just put coffee in my printer to see...

It kinda works, but the printouts are very faint.

I was expecting it to clog immediately (the jets are ~10um), but it didn't.

Damn. The kind of friends I need in my life.

Sorry to bother you but I have so many questions! Like, did you actually do it or was it just a middle joke I didn't detect? If the former, wasn't you afraid the printer won't be usable after that experiment? Didn't that worry you? Do you often experiment in this way? (Just stopping there to give otherwise the list gets too long.)

I have literally hundreds of HP print heads from a project, many partly blocked or burned out (they burn if you send them the wrong signals, and like 10% of the time I hit 'break' on my debugger it burns a few jets out if they're firing at the time), and had a coffee sitting right next to my desk so thought "why not".

yeah, but can you bubble jet maybe a photo onto a flat white?

That is a stretch goal of my project, but right now I wouldn't be confident I have a method to flush out the OEM and probably toxic ink.

This is incredible - you should write a blog about it. I want to see what that printout looks like!

When the main project is done, there'll be a blog post and the coffee test will make an appearance!

I'm also super curious what one might get up to with that many print heads, so maybe there's two posts in there!

I'm not surprised if you used the Breakfast Blend. Did you try the Caffe Verona or Espresso Roast?

It was Lidl's red topped instant - don't even know the name - the jar with the red lid, and I made it pretty strong but without milk/sugar (which I thought would cook/burn onto the inside of the nozzle)

That's my printer recommends Bulletproof Coffee. The coconut oil helps ensure smooth flow without clogging while the MCTs improve coffee adhesion to the paper.

Is that a business they even want, someone occupying a seat for 8 hours only to consume two coffees?

They'd rather that than an empty seat, especially if that person is turning up 5-6 days/week.

Most coffee shops where I live (London, UK, specifically out in West London) are at best 20% full through most of the day, that's a lot of dead real estate not paying for itself.

When I tried working out of coffee shops a bit some years ago the "etiquette" seemed to be ~1 drink/hour to pay for your seat. I don't like coffee that much, so was consuming more like 0.66/hour (i.e. around 2 drinks every 3 hours), and people were fine with that, as it was effectively a rent payment of £20/day, or £100/week, which is a little under what a hotdesk would cost me in the same area but with a lot more flexibility (never pay for idle!), and of course its good margin sales for them.

Of course, they could just say "no laptops". There's a pub chain in the UK that did that (Sam Smith's - no screens, no swearing), but the rule is not widely followed or enforced and where it is the pubs are empty far more than the ones that welcome customers.

Obviously some coffee shops are gonna want that but some coffee shops are making all their money by selling to customers during short periods in the morning, lunch and maybe in the afternoon and if this person is sitting there blocking the chair that could be used by many customers during the time the total of two cups of coffee will be less than what they are losing from not being able to serve those customers. Of course for some coffee shops they are never full and they probably benefit from this and they would love to have those type of customers.

>> but the rule is not widely followed or enforced and where it is the pubs are empty far more than the ones that welcome customers.

I mean, I went to one in SOHO and it was packed and indeed, no one was on their phone and people were being actively told off if they used a phone. That was nice. The fact that I paid £9 for a pint was much less nice though.

I believe there was an HN article recently about a business that provides a service to cafes to formalize that rent agreement. Spend a certain amount (e.g. 8 euros every 3 hours) or you lose wifi access.

The problem isn't your one coffee an hour during the lull of the day. It's you taking up a table at lunchtime that could be occupied by 4 customers who will outspend your entire day by several times over. Sure the place is mostly empty for most of the day but your cheap ass is taking a seat during the precious hours where they make their profit.

Customers attract customers. Even if some customers are not spending a lot of money, they bring in other customers who more than make up for them. This is the reason why so many coffee shops go out of their way to provide power outlets near every table.

They want people, but I think a printer crosses the line. It's a Starbucks not a Kinko's.

It's even worse, I don't think you can bring your own printer to a Kinko's.

When I worked out of free co-working spaces in Asia I would buy lunch and breakfast from them too, both to socialize with other patrons and to not lose my seat.

I work from a coffee shop a good bit. They don’t care for the most part. Assuming you tip reasonably, be nice to the staff, don’t be annoying, don’t negatively impact the other customers, be helpful when the occasion calls for it.

I presume it's highly subjective.

For a busy cafe that's always short on seating and struggles to keep up with fulfilling orders, they want nothing to do with laptop squatters.

Every other case I imagine it's desirable to have at least some regulars presumably employed enough to be working from a cafe using modern tech.

One common problem I've noticed is van lifers and other quasi homeless folks spending ~zero money stinking up the place just for the free power and internet.

Now that battery life and cell-tethered internet is so good, some of my favorite urban cafes have adopted a no-outlets no-wifi approach, while still having tons of seating and allowing folks to be present with their computers all day. They just have to provide their own internet and power, which serves to exclude the true parasites while selecting for folks with $$ to spend because they have state of the art gadgets with their own unlimited data plans.

Then they'd have two problems: people camping out in the stores and managing thousands of printers.