The making of the shot glass

I'd printed the raft last night and finished about 0400 this morning, not that it took that long, mind, but I was having a bit of previously mentioned drama with the Mk 1 AEM extruder. For a 75% heating/40% gearmotor setting I found that 99% of the clutch slippage on the gearmotor was happening when I tried to back up the filament a touch between laying down filament.



I watched the print for a while and when nothing exciting happened went off into the kitchen of my flat to wash dishes and do a bit of breakfast. Of course, my impulse control isn't that wonderful so I peeked out to make sure that nothing horrible had happened every few minutes.



Mostly, there was not much to see except a slowly growing shot glass. I still have a little x-axis drift but it's consistent now and doesn't really ruin prints.



When I wrote the little routine to develop the sides of the glass yesterday I had a bit of a difficult time taking in that the volume of a glass varies as the square of it's radius, not linearly.


I knew that intellectually, but when you're just designing a glass it's sometimes a little difficult to get your head around the reality. As a result of that, my first glass was 15 mm in diameter, just about big enough to get the tip of my little finger in.



I then overcompensated and did a few layers of one with a 75 mm diameter. That one would have been suitable for either ice tea or liver damage.



After four more tries I settled on a 35 mm diameter, straight-sided, octagonal shot glass.



I then realised that I really didn't know how much was supposed to be in a shot glass since it's been many years since I drank regularly enough to keep a grip on that kind of trivia.



One ounce (30 ml) came to mind and after a Google search I found that in this, at least, my memory hadn't betrayed me. This at 0200 in the morning, mind. Then, I remembered that RepRap is a British managed project, so I did some more looking and discovered that a British shot glass comes in 25 ml and 35 ml sizes.

For the 35 mm diameter I had a depth of 20 mm would give me 26 ml which is a small British shot glass with enough of a lip to avoid unnecessary spillage.
I had a quick shot and after a moments consideration decided that another was due since I'd resolved back in February not to drink any of my 12 year-old McAllan's single malt till I'd printed a glass to drink it with.


That ... was perhaps not such a good idea. As I said, I don't drink a lot. On top of that I hadn't made any breakfast and had got about 3 hours sleep the previous night. About half-way through the second shot the effect of the ethanol hit me and I had to stop and consider things for a moment before I finished it. It was then I realised that the sun was definitely NOT over the yardarm, seeing it was right at 1000.

Anyway, that is my account of the printing of the shot glass. The McAllan's goes back in the liquor cabinet which is otherwise known as my hall closet, a space that also acts as storage for many other useful things including toothpaste and vacuum cleaner bags.