cappuchino / latte cups with 60ml mark
I'm wondering if anyone sells any large cappuchino / latte sized cups / mugs with a 60ml mark, whenever I do a manual brew? It would be nice to not need to use my shot glass which has 30/60ml marks.
I think the diameter of the cup would be the biggest issue. My shot glass measuring cups are about 4cm diameter at the lip (2cm at the base) and about 3cm of height to hit the 30ml line. So roughly 1mm of height per ml average. My Cappuccino cups are about 8cm inner diameter at the top and 6cm at the bottom. For a cylinder with vertical sides, at 3cm diameter you only need to have just over 1cm of height to hit 30ml. At 6cm diameter you need just 2.65mm of height to hit 30ml, or 5.3mm to hit 60ml. 5.3mm of height is going to be extremely hard to be accurate to stopping a shot in time, let alone the precision equipment required to make a cup with an accurate line. I don't even know of cups like that with lines printed on the inside, all the measuring cups I've seen are printed on the outside.
Add to that all the variety of colours and styles of cups that are available from any one manufacturer and I can't see it being a viable product for anyone to make.
You'd be just as accurate without a line but learning roughly what 60ml looks like in your cups. Or even forget the volume and learn what the shot looks like as it pours and when you should cut it off. In my experience this is more accurate to taste over a volume measurement because subtle variations in bean age, grind settings and dosing will all give different pours.