SBC 9 - Day 2

Today was supposed to be putting in flutes but the bowl was no where near ready. I got to work about 10 am and went through 7 more rounds of raising to pull the walls up to vertical. Luckily I had essentially finished the hemisphere portion of the bowl yesterday so I didn't have to go over that area any more. That makes the rounds go faster. But it's still slow going to get that much metal to come in and form a smooth vertical surface. I should note that this is the first time that I've tried to do this kind of shape. I'm used to conical or egg shapes and a cylinder was new to me. But it went pretty well and finally got to a point where I could start the next phase.

Round 10

Round 11

Round 12

Round 13

Round 14

Round 15

Round 16

Raising makes an uneven edge at the top and I wanted to cut that off so that the shape was ready to planish. I used a surface gauge instead of the dividers I had been using to scribe guide lines. That's so I was sure to have the edge parallel to the foot. I cut off the excess with shears and then evened and flattened the rim with a file and a belt sander. A little sandpaper to smooth the rim and the basic shape was done.

Rough edges must go.

Using a surface gauge to mark the trim line.

Neatly trimmed.

Then it was on to planishing the cylinder portion of the bowl. The hemishpere was pretty well done yesterday but there were a lot of raising marks that needed to be smoothed out. In the process I also made sure that the cylinder didn't have any dips or bulges or waves left over from when the shape was being formed. Normally this would be done on a cylinder stake of a size that matched the curve. But I don't have one and didn't have time to make one. So I improvised with the 3" sphere stake, my large raising stake, and a process where I gridded off the cylinder into 8 columns and three rows and worked them over in sequence by columns from bottom to top. As each area got planished it also got blended with the areas below and behind it. By the end of the process, I had a smooth cylinder. Then the foot got a little attention and the whole thing was planished and ready to prepare for chasing.

All planished and shiny.

I want to be able to start up tomorrow ready to lay out the flutes and get right to chasing. To do that, I have to fill the bowl with chaser's pitch or something like it. I've been using red sculptor's was for this instead of actual chaser's pitch. I'm following David Huang's recommendation in this and have found that it works quite well and causes fewer problems for me than the pitch. Before filling the bowl, I annealed it one more time so that it would be soft and workable for the chasing punches. That's when I got a surprise.

I'd been annealing this bowl frequently for two days. Somehow it had escaped me that when it was quenched after annealing and before pickling it didn't look the way copper usually does. After pickling it looked like normal copper, a lovely pale pink. But before that it looked oddly bronze-ish and mottled. Well, after this pickling I wanted to scrub it up nice and clean  so layout lines would show up well. That's when I noticed that the scrubbed parts looked golden yellow, not coppery. What the...? A quick check with a file on a piece of the sheared off edge confirmed it. I've been working 16 gauge brass for two days. No wonder I was getting tired!

Yep. I'm an idiot.

With that out of the way I filled the bowl with wax and left it to cool while I had dinner. Tomorrow I'll do the layout of the flutes and see if I can get them chased in before the day is done.

Ready to fill.

Filled and cooling.

It's been a long fun day. See you tomorrow.