So today I finished paying my debt to society for speeding in the mountains of California. Yes I went to traffic school, online traffic school to be more specific, drivinguniversity.com to be exact. For a mere $19.95 and three hours of my time, I was able to have my moving violation tansmogrified into something that won't go on my record. It required more time and attention than I expected. They even embedded non-driving information in the text in order to quiz me to make sure I was reading everything and not just skimming. For instance:
Jeff Bezos, the founder of Amazon.com was originally going to name his web venture Cadabra.
Probably my favorite part was the rhetorical question:
How far does your car travel and how much do you miss when you take your eyes off the road [to]:
Dip a French fry in ketchup?
Dial the phone?
Look at a map?
Hand the baby a bottle?
Read a billboard?
Put cream in your coffee?
Glance at the accident scene across the street?
I don't know how long it takes for each of these things, but I'm sure if I was timing such events it would distract me from driving even longer.
At any rate, it is done. I have only to confirm that my certificate of completion is sent to the courthouse and then go at least 18 months without getting pulled over in California, which means my upcoming trip to San Jose will probably take at least half an hour longer than it usually does.
Sunday, May 28, 2006
Sunday, May 21, 2006
Cones for Kinetic Sculptures
What's this? A pottery post on the pottery blog? Who could imagine?
I'm starting work on kinetic sculptures. The basic idea is to have a central support (in this case a cone) with a separate piece that balances on the apex of the cone. This will be achieved by having extensions of the balancing piece much lower than the top of the cone so that the center of gravity is lower than what is balanced on top of the cone. If that's not clear, then you'll have to wait until I'm further along.
At any rate, this is a prototype cone. I threw a cylinder then collared it into a cone shape. The depressed portion on the top was done by attaching a small lump of clay and shaping it.
The photo below shows the parts for a larger cone thrown in two pieces. The bottom portion was thrown as you would a bowl. The top is inverted with the wider part at the top. It should be ready to assemble in a couple of days. More pictures then.
I'm starting work on kinetic sculptures. The basic idea is to have a central support (in this case a cone) with a separate piece that balances on the apex of the cone. This will be achieved by having extensions of the balancing piece much lower than the top of the cone so that the center of gravity is lower than what is balanced on top of the cone. If that's not clear, then you'll have to wait until I'm further along.
At any rate, this is a prototype cone. I threw a cylinder then collared it into a cone shape. The depressed portion on the top was done by attaching a small lump of clay and shaping it.
The photo below shows the parts for a larger cone thrown in two pieces. The bottom portion was thrown as you would a bowl. The top is inverted with the wider part at the top. It should be ready to assemble in a couple of days. More pictures then.
O-M-G He washed the car!
For anyone who knows me, or has seen this car in the past year, you will be amazed to hear that not only did I wash it, I vacuumed it, waxed it, and Armor-alled the vinyl. (Note the distinct lack of bird droppings.)
Replacing headrest speakers in a 1992 Mazda Miata
I am fortunate to own a 1992 Mazda Miata with 100+ k miles on it. As old as it is, it's in good shape. I will be driving it to San Jose in a couple of weeks, so last week I decided to replace the worn out, original headrest speakers. This post is for the benefit of anyone else undertaking this excercise. Please keep in mind that this is what I did. What you do to your car is at your own risk!
Removing the speaker box.
Start by unzipping the zipper on top of the headrest. Unscrew the top and bottom screws holding the speaker box in.
Removing the original speaker from its box.
Unscrew the four corner screws holding the speaker in the speaker box. Then pry the old speaker out with a screwdriver. Yes, this destroys the old speaker.
Once the speaker is out of the box, disconnect the leads to the speaker. These should slide right off.
Force out the plug where the wires enter the box.
I did this by prying and pushing with a flat blade screwdriver.
Mark the foam for the new speakers.
I bought some 3 1/2 inch Clarion coaxial speakers. These are 4 ohm speakers as were the speakers that I removed from the old boxes. I assume it is important to match the impedence.
Snip the foam to make room for the new speakers.
I just poked and snipped with a pair of pointed scissors.
Install the new speakers.
The clips on the wire leads fit the tabs on the new speakers. I simply slid the clips on and shoved the new speakers into the cutouts in the foam then closed up the headrest. The pressure against the speakers is holding them in place.
Removing the speaker box.
Start by unzipping the zipper on top of the headrest. Unscrew the top and bottom screws holding the speaker box in.
Removing the original speaker from its box.
Unscrew the four corner screws holding the speaker in the speaker box. Then pry the old speaker out with a screwdriver. Yes, this destroys the old speaker.
Once the speaker is out of the box, disconnect the leads to the speaker. These should slide right off.
Force out the plug where the wires enter the box.
I did this by prying and pushing with a flat blade screwdriver.
Mark the foam for the new speakers.
I bought some 3 1/2 inch Clarion coaxial speakers. These are 4 ohm speakers as were the speakers that I removed from the old boxes. I assume it is important to match the impedence.
Snip the foam to make room for the new speakers.
I just poked and snipped with a pair of pointed scissors.
Install the new speakers.
The clips on the wire leads fit the tabs on the new speakers. I simply slid the clips on and shoved the new speakers into the cutouts in the foam then closed up the headrest. The pressure against the speakers is holding them in place.
Thursday, May 18, 2006
Is that Newley as in Anthony?
Today at work, three of us watched as workers at the hotel next door put the following sign together. I guess our boss isn't the only one who should worry about whether the employees are getting things done.
Monday, May 15, 2006
Rollerblading on the Bike Path - 2006.05.14
Why turtles in a blog entry about rollerblading? The bike path is next to the river and goes around and over some wetlands. On the first really warm day of the year, what would you do if you were a turtle. I'd do what the rest of the turtles do and soak up the sun.
No fears alone at night she's sailing through the crowd / In her ears the phones are tight and the music's playing loud
- Mark Knopfler
Blazing down the bike path in his penguin shirt, Rollerboy is but a blur.
No fears alone at night she's sailing through the crowd / In her ears the phones are tight and the music's playing loud
- Mark Knopfler
Blazing down the bike path in his penguin shirt, Rollerboy is but a blur.
Sunday, May 14, 2006
2006.05.08
This house is about 2 blocks away from us. It caught on fire last night. The firetrucks screamed into the neighborhood and the firemen cut into the house and doused the flames. We didn't hear a thing, read about it in the paper the this morning.
Easter Weekend - Pacific City, OR
Along with our friends, Steve and Jen and their son Evan, we rented a house on the beach in Pacific City, OR, our favorite place in the state. It was a relaxing time, full of good food, nice walks, and cards. The weather was a little rough, but hey, we were still at the beach!
The wind was blowing and the surf was up. If you were patient, very patient, you could get a picture of a wave breaking over Cape Kawanda (about 30 ft high?). This one was taken from inside our house. Unfortunately, with all the wind, the window was spattered with the spray, hence the abysmal quality of the photo.
This little guy (about the size of a quarter) is a valella. These jellyfish-like beasties float and ride the wind with their sail. The ones we saw were between the size of a dime and an quarter. The picture below was taken on the beach in Oceanside. They were so thick on the beach there, you couldn't avoid them. They caked up on our shoes. When we got there, the folks leaving from the beach wedding looked none too cheery, ptobably due to these and the extreme wind.
The upside to the valella washing in is that the same winds also bring in floats from fishing nets. We found about 4 small ones and a larger one, about a 10 inches in diameter.
The wind was blowing and the surf was up. If you were patient, very patient, you could get a picture of a wave breaking over Cape Kawanda (about 30 ft high?). This one was taken from inside our house. Unfortunately, with all the wind, the window was spattered with the spray, hence the abysmal quality of the photo.
This little guy (about the size of a quarter) is a valella. These jellyfish-like beasties float and ride the wind with their sail. The ones we saw were between the size of a dime and an quarter. The picture below was taken on the beach in Oceanside. They were so thick on the beach there, you couldn't avoid them. They caked up on our shoes. When we got there, the folks leaving from the beach wedding looked none too cheery, ptobably due to these and the extreme wind.
The upside to the valella washing in is that the same winds also bring in floats from fishing nets. We found about 4 small ones and a larger one, about a 10 inches in diameter.
Sunday, May 07, 2006
Reno Baby! (2006.04.01)
Reno (or at least Sparks) Baby!
It's April First, 10:34 a.m. and I find myself sitting at a lounge
table in the "John Ascuaga Scholarship Hall of Fame" at "John
Ascuaga's Nugget Hotel and Casino" in Sparks, Nevada (Adjacent to
Reno). Pictures of past scholarship winners hang in glass frames
across from a nameless bar. Morning patrons, a handful of them, sit
at the bar and a few take advantage of the "Bloody Mary Buffet" cart
situated between the bar and the copper-topped bay window display of
rotisserie chickens.
Two Asian gentlemen in suits sit one table away, smoking Marlboros and
talking. At another table, an East Indian mother and daughter -- both
in Saris -- and son watch their husband/father play a nearby "Wheel of
Fortune" slot machine. A Beatles tune from the early sixties is
nearly lost in the beeps, chirps, and rings from the countless gaming
machines in the casino. An occasional refugee from the sports
marketing convention strolls by, trailing a yellow m&m's wheelie
cooler. Those sports marketing people get all the good stuff!
As if this isn't enough of a cosmic April Fool's joke, the mouse
button on my computer's touch pad has gone on the fritz, deciding at
random that it is being held down even though it has been released.
Luckily my mouse is close at hand.
So, you may ask me, "Well, how did you get here?"
Kim's American Acadamy of Advertising (AAA) meeting is in Reno, and
unable to resist anything as shiny as a casino, I came along as a
trailing spouse.
We drove down on Wed. A straight shot down I-5 and then west on a
variety of state highways in CA and NV. I-5 was smooth and the route
west was a gorgeous drive on clear roads through snowy pine forests.
The Nugget. What can you say about it. Two 25 foot story towers, six
or seven restaurants, and a casino. Its a rockin' place. In fact
it's the only place I've ever been where hits from the 60's, 70's, and
80's are piped into the parking garage. It rocks hard. They have a
"golden" rooster in a display case. See the picture to prove
it. (click for a good write-up of the Nugget).
Wed. Night, we had dinner at a bar/restaurant in the casino.
Random observations:
- A large percentage of weekday gamblers are old.
- People bring their children here. Why?
- Quite a few of the senior gamblers have cards (I assume cash cards)
that plug into the machines. These are tethered to their belt by a
curly cord. When they sit in front of the machine with that cord
running from the slot machine to their body, they look like the
machine is providing life support. Hmmm...
- If you are a woman in your 50's, a bit overweight, and puffy (as if
on steroids), you will probably not looked good with spiked
bleach-blonde hair, tight jeans rolled up to capri length, and zebra
striped high-tops.
Our friend Steve gave us $2.00 in quartes for the express purpose of
building his son's college fund. We chose a lucky looking machine and
ran the quarters through. If you've never played a slot machine,
here's a way to experience it without leaving home:
Take a handful of quarters into the bathroom. Drop one into the
toilet and pull the handle. Look to see if any quarters came out of
the front of the toilet. Repeat until you are out of quarters. If
you're running short on time, you can always drop in multiple quarters
per flush.
Needless to say, Steve's son won't be going to Harvard law on what
we are (or are not) bringing back for him.
Thursday Kim spent the day at the conference. I bought a zoom lense
for my camera at a local camera store (Gordon's, very pleasant and
very helpful) and headed 35 miles north to Pyramid Lake. This lake is
a remnant of the prehistoric, 84,000 square mile Lake Lahontan. It is
fed in part by hot springs, which form calcium carbonate structures
know as tufas. These dot the landscape around the shores, and some
stick out of the lake. The pyramid rock formation for which the lake
is named is a tufa. Large trout inhabit the lake as do white
pelicans. I came primarily for the tufas and the pelicans and was not
disappointed. With the zoom lense I was able to get some good shots
of a group of pelicans. Photographing the tufas was much less of
a challenge.
(Lest you forget where I am right now, two tables away a young man is
lighting a cigarette for his female companion. This is remarkable
only because her hair is just on the green side of azure.)
Friday, Kim and I checked out nearby Victorian Square. A collection
of shops (including one pawn shop), restaurants, and a museum. We
were hoping to get crepes for breakfast, but the crepe restaurant
didn't open until 10:00.
In the afternoon we went to the Harrah's Car Museum, which has about
200 cars from the late 1800's on. This place is amazing. Probably
two thirds of the cars are from before 1930. They have cars you never
heard of (for example a two-seat, five-wheeled buckboard, made by
Briggs and Stratton. The power was provided by a 5th wheel.).
Apparently Mr. Harrah was quite the collector of cars. When he died
the collection was auctioned off. The museum is trying to buy them
all back.
Friday night we enjoyed a dinner at Ozorko's, the nice restaurant in
the hotel. After that we burned through about $2.00 worth of nickels
in the slots. We were the only two people I have seen in the whole
place for whom playing on slot machine is a couple's activity.
Imagine one person dropping the coin in the toilet while the other
flushes. We finished the evening by watching "Six Feet Under" on DVD
on the Mac. Wild Times in Reno, baby!
So that's my Reno story so far. Kim is in meetings until 3:00, when
we hit the road. I'm at loose ends until then. It's now noon, so I'm
going to see about going to the Parks Museum and grabbing lunch. I'm
sure I'll have a little more later.
2:00 - I'm baaaack
I'm sitting in the lobby across from the reception desk. To my right a man is making calls on his cell phone talking about who and how is betting on the college hoops final four, what the spreads are, etc. A woman to his right, who apparently knows him, occasionally chimes in with why who is betting how on these games. The money they are talking is a whopping $50 per game (and no, not $50,000). The way they are talking about the strategies and the plan, you'd think they were preparing to bring down the house.
On my way over to the Parks Museum, I stopped to look in the pawn shop window. Rows of cards with jewelry attached: earrings, rings, mostly sterling and zirconia, a few small diamonds in gold, a wedding set, a gold pendant depicting a woman bowling, her ball a black pearl. As I was about to move on, the door to the pawn shop swung open, out walked a man and woman with two toddlers in tow, headed back in the general direction of the casino.
The museum was your typical, small western town, volunteer museum.
Pictures of petroglyphs, a stuffed bear, railroad paraphanalia, old
telephone and post office equipment and furntiure...I love places like
that. It's not the Smithsonian, but it is as real as it gets. From
museum I went over to the authentic Irish Pub, had an authentic Irish
burger with blue cheese, while authentic Irish music (Elvis Presley,
AC/DC, some country western tune) played on the jukebox. I guess
St. Pat's decorations and Guinness on tap are what make a pub
officially Irish. I opted not to play the video poker on the screens
mounted in the bar.
After the pub, a quick stop to check out the old steam train next to
the "historic" little wooden train station.
And so, my time in Reno...er...Sparks draws to an end. Our ETD is in
35 minutes. Just enough time to watch a few more people go by -- with
or without yellow m&m coolers -- and be glad I live in a greener,
quieter place.
A quick postscript. They were predicting snow in the mountains in CA,
so I tried to beat the snow by driving a little fast. The patrolman
was very nice, but still gave me a ticket :(
It's April First, 10:34 a.m. and I find myself sitting at a lounge
table in the "John Ascuaga Scholarship Hall of Fame" at "John
Ascuaga's Nugget Hotel and Casino" in Sparks, Nevada (Adjacent to
Reno). Pictures of past scholarship winners hang in glass frames
across from a nameless bar. Morning patrons, a handful of them, sit
at the bar and a few take advantage of the "Bloody Mary Buffet" cart
situated between the bar and the copper-topped bay window display of
rotisserie chickens.
Two Asian gentlemen in suits sit one table away, smoking Marlboros and
talking. At another table, an East Indian mother and daughter -- both
in Saris -- and son watch their husband/father play a nearby "Wheel of
Fortune" slot machine. A Beatles tune from the early sixties is
nearly lost in the beeps, chirps, and rings from the countless gaming
machines in the casino. An occasional refugee from the sports
marketing convention strolls by, trailing a yellow m&m's wheelie
cooler. Those sports marketing people get all the good stuff!
As if this isn't enough of a cosmic April Fool's joke, the mouse
button on my computer's touch pad has gone on the fritz, deciding at
random that it is being held down even though it has been released.
Luckily my mouse is close at hand.
So, you may ask me, "Well, how did you get here?"
Kim's American Acadamy of Advertising (AAA) meeting is in Reno, and
unable to resist anything as shiny as a casino, I came along as a
trailing spouse.
We drove down on Wed. A straight shot down I-5 and then west on a
variety of state highways in CA and NV. I-5 was smooth and the route
west was a gorgeous drive on clear roads through snowy pine forests.
The Nugget. What can you say about it. Two 25 foot story towers, six
or seven restaurants, and a casino. Its a rockin' place. In fact
it's the only place I've ever been where hits from the 60's, 70's, and
80's are piped into the parking garage. It rocks hard. They have a
"golden" rooster in a display case. See the picture to prove
it. (click for a good write-up of the Nugget).
Wed. Night, we had dinner at a bar/restaurant in the casino.
Random observations:
- A large percentage of weekday gamblers are old.
- People bring their children here. Why?
- Quite a few of the senior gamblers have cards (I assume cash cards)
that plug into the machines. These are tethered to their belt by a
curly cord. When they sit in front of the machine with that cord
running from the slot machine to their body, they look like the
machine is providing life support. Hmmm...
- If you are a woman in your 50's, a bit overweight, and puffy (as if
on steroids), you will probably not looked good with spiked
bleach-blonde hair, tight jeans rolled up to capri length, and zebra
striped high-tops.
Our friend Steve gave us $2.00 in quartes for the express purpose of
building his son's college fund. We chose a lucky looking machine and
ran the quarters through. If you've never played a slot machine,
here's a way to experience it without leaving home:
Take a handful of quarters into the bathroom. Drop one into the
toilet and pull the handle. Look to see if any quarters came out of
the front of the toilet. Repeat until you are out of quarters. If
you're running short on time, you can always drop in multiple quarters
per flush.
Needless to say, Steve's son won't be going to Harvard law on what
we are (or are not) bringing back for him.
Thursday Kim spent the day at the conference. I bought a zoom lense
for my camera at a local camera store (Gordon's, very pleasant and
very helpful) and headed 35 miles north to Pyramid Lake. This lake is
a remnant of the prehistoric, 84,000 square mile Lake Lahontan. It is
fed in part by hot springs, which form calcium carbonate structures
know as tufas. These dot the landscape around the shores, and some
stick out of the lake. The pyramid rock formation for which the lake
is named is a tufa. Large trout inhabit the lake as do white
pelicans. I came primarily for the tufas and the pelicans and was not
disappointed. With the zoom lense I was able to get some good shots
of a group of pelicans. Photographing the tufas was much less of
a challenge.
(Lest you forget where I am right now, two tables away a young man is
lighting a cigarette for his female companion. This is remarkable
only because her hair is just on the green side of azure.)
Friday, Kim and I checked out nearby Victorian Square. A collection
of shops (including one pawn shop), restaurants, and a museum. We
were hoping to get crepes for breakfast, but the crepe restaurant
didn't open until 10:00.
In the afternoon we went to the Harrah's Car Museum, which has about
200 cars from the late 1800's on. This place is amazing. Probably
two thirds of the cars are from before 1930. They have cars you never
heard of (for example a two-seat, five-wheeled buckboard, made by
Briggs and Stratton. The power was provided by a 5th wheel.).
Apparently Mr. Harrah was quite the collector of cars. When he died
the collection was auctioned off. The museum is trying to buy them
all back.
Friday night we enjoyed a dinner at Ozorko's, the nice restaurant in
the hotel. After that we burned through about $2.00 worth of nickels
in the slots. We were the only two people I have seen in the whole
place for whom playing on slot machine is a couple's activity.
Imagine one person dropping the coin in the toilet while the other
flushes. We finished the evening by watching "Six Feet Under" on DVD
on the Mac. Wild Times in Reno, baby!
So that's my Reno story so far. Kim is in meetings until 3:00, when
we hit the road. I'm at loose ends until then. It's now noon, so I'm
going to see about going to the Parks Museum and grabbing lunch. I'm
sure I'll have a little more later.
2:00 - I'm baaaack
I'm sitting in the lobby across from the reception desk. To my right a man is making calls on his cell phone talking about who and how is betting on the college hoops final four, what the spreads are, etc. A woman to his right, who apparently knows him, occasionally chimes in with why who is betting how on these games. The money they are talking is a whopping $50 per game (and no, not $50,000). The way they are talking about the strategies and the plan, you'd think they were preparing to bring down the house.
On my way over to the Parks Museum, I stopped to look in the pawn shop window. Rows of cards with jewelry attached: earrings, rings, mostly sterling and zirconia, a few small diamonds in gold, a wedding set, a gold pendant depicting a woman bowling, her ball a black pearl. As I was about to move on, the door to the pawn shop swung open, out walked a man and woman with two toddlers in tow, headed back in the general direction of the casino.
The museum was your typical, small western town, volunteer museum.
Pictures of petroglyphs, a stuffed bear, railroad paraphanalia, old
telephone and post office equipment and furntiure...I love places like
that. It's not the Smithsonian, but it is as real as it gets. From
museum I went over to the authentic Irish Pub, had an authentic Irish
burger with blue cheese, while authentic Irish music (Elvis Presley,
AC/DC, some country western tune) played on the jukebox. I guess
St. Pat's decorations and Guinness on tap are what make a pub
officially Irish. I opted not to play the video poker on the screens
mounted in the bar.
After the pub, a quick stop to check out the old steam train next to
the "historic" little wooden train station.
And so, my time in Reno...er...Sparks draws to an end. Our ETD is in
35 minutes. Just enough time to watch a few more people go by -- with
or without yellow m&m coolers -- and be glad I live in a greener,
quieter place.
A quick postscript. They were predicting snow in the mountains in CA,
so I tried to beat the snow by driving a little fast. The patrolman
was very nice, but still gave me a ticket :(
Sunday, June 12, 2005
Glazing
I started doing pottery at a community studio in Oak Ridge, TN when I worked at Oak Ridge National Lab. The glazes there were mixed by the instructor and some of his assistants. Firing was done in electric kilns equipped with kiln sitters. Results were mixed.
When I moved to Oregon, I bought various ^6 commercial glazes a couple didn't work to well, and a few did. A couple of years ago, I bought a Skutt kiln with a computerized controller. I also started using a variety of Laguna clays. I got to a point where I thought I had several glazes that worked pretty well.
And then I did the Christmas present mugs. For each of my siblings, their kids, and spouses I made a mug from Laguna ^5 Morrocan Sand. I attatched a variety of images cut from slabs of the same clay onto each mug. I glazed the insides by pouring and the outsides by hand application onto the applied images.
After firing, I had cracked mugs, runny glazes, and crazing. A lot of work down the drain.
That's when I decided to learn how to make glazes. I found Mastering Cone 6 Glazes by John Hesselberth and Ron Roy. I cannot recommend this book highly enough.
The first thing I did was to mix up the glazes they recommend for testing coefficients of expansion. These are used to get a handle on the coefficient of expansion for the clay you are using. This part of the process went great. I was able to get a test glaze that would not craze or shiver when doing the heat/quench test on the clays I was using.
My next step was to get a base glossy glaze. I chose their Glossy Base Glaze1 from p. 92. I kept most of it plain, but added a little cobalt to some and some rutile to some. I glazed some mugs and pots and fired them to ^6.
And got a big, rude surprise. At ^6, the Laguna Moroccan Sand clay body I liked so much warped badly (see the picture).
So then I tried firing it to ^5 with a 20 minute hold at 2185 F and a cooling rate of 150 F down to 1500 F. And the &#%* Moroccan Sand warped and slumped on several pieces. In addition, the glaze had more of a semi-matte texture.
I made a couple of attempts by adding more boron to the glaze and using Laguna Colonial white as a control. The Colonial white came out glossy, the glazes I mixed myself were still semi-matte.
By this time, I was mainly making jellyfish (see prev. posting) and was having good results with CW as a base glaze and using a couple different glazes (Laguna Regal Blue and Laguna Blackberry) as light overglazes. So I took a hiatus from making my own glazes.
Now I am preparing to make another foray. I've done quite a bit more web research and come across a couple of different things:
1) Ravenscrag slip
This stuff sounds like the best thing since sliced slab tiles. At ^10 it is a glaze by itself. For ^6, one just needs to mix it with ~20% Frit 3134. It is supposed to go on like a dream and perform well for multilayering. I've bought some and will try it.
2) Great Results from Electric Kilns
A presentation by John Hesselberth that in part discusses factors that effect glazes. Most notable for me was the section showing the effects of slow vs fast cooling.
I now have 3 possible suspects for my glossy glaze turning out semi-matte:
a) Not being fired high enough. As a result the glaze is not melting completely. This would be very bad for glazes used with food as it would lead to leaching.
b) The glaze composition is not what I think due to variations in materials. This could result in unmelted glaze.
c) Cooling too slowly. Micro crystals could be forming as the glaze cools. This would not necessarily mean a glaze that would lead to leaching, but it's still not the glossy glaze I am after.
So as I look forward to glaze development, I will be revisiting the Hesselberth and Roy Glossy 1 glaze and pay attention to the cooling rate at the same time I test glazes based on Ravenscrag Slip.
I haven't talked about glaze software, but undoubtedly will in a future post. I am using Digital Fire's Insight software on a trial basis. I'm sure that when my trial ends I will be purchasing it.
When I moved to Oregon, I bought various ^6 commercial glazes a couple didn't work to well, and a few did. A couple of years ago, I bought a Skutt kiln with a computerized controller. I also started using a variety of Laguna clays. I got to a point where I thought I had several glazes that worked pretty well.
And then I did the Christmas present mugs. For each of my siblings, their kids, and spouses I made a mug from Laguna ^5 Morrocan Sand. I attatched a variety of images cut from slabs of the same clay onto each mug. I glazed the insides by pouring and the outsides by hand application onto the applied images.
After firing, I had cracked mugs, runny glazes, and crazing. A lot of work down the drain.
That's when I decided to learn how to make glazes. I found Mastering Cone 6 Glazes by John Hesselberth and Ron Roy. I cannot recommend this book highly enough.
The first thing I did was to mix up the glazes they recommend for testing coefficients of expansion. These are used to get a handle on the coefficient of expansion for the clay you are using. This part of the process went great. I was able to get a test glaze that would not craze or shiver when doing the heat/quench test on the clays I was using.
My next step was to get a base glossy glaze. I chose their Glossy Base Glaze1 from p. 92. I kept most of it plain, but added a little cobalt to some and some rutile to some. I glazed some mugs and pots and fired them to ^6.
And got a big, rude surprise. At ^6, the Laguna Moroccan Sand clay body I liked so much warped badly (see the picture).
So then I tried firing it to ^5 with a 20 minute hold at 2185 F and a cooling rate of 150 F down to 1500 F. And the &#%* Moroccan Sand warped and slumped on several pieces. In addition, the glaze had more of a semi-matte texture.
I made a couple of attempts by adding more boron to the glaze and using Laguna Colonial white as a control. The Colonial white came out glossy, the glazes I mixed myself were still semi-matte.
By this time, I was mainly making jellyfish (see prev. posting) and was having good results with CW as a base glaze and using a couple different glazes (Laguna Regal Blue and Laguna Blackberry) as light overglazes. So I took a hiatus from making my own glazes.
Now I am preparing to make another foray. I've done quite a bit more web research and come across a couple of different things:
1) Ravenscrag slip
This stuff sounds like the best thing since sliced slab tiles. At ^10 it is a glaze by itself. For ^6, one just needs to mix it with ~20% Frit 3134. It is supposed to go on like a dream and perform well for multilayering. I've bought some and will try it.
2) Great Results from Electric Kilns
A presentation by John Hesselberth that in part discusses factors that effect glazes. Most notable for me was the section showing the effects of slow vs fast cooling.
I now have 3 possible suspects for my glossy glaze turning out semi-matte:
a) Not being fired high enough. As a result the glaze is not melting completely. This would be very bad for glazes used with food as it would lead to leaching.
b) The glaze composition is not what I think due to variations in materials. This could result in unmelted glaze.
c) Cooling too slowly. Micro crystals could be forming as the glaze cools. This would not necessarily mean a glaze that would lead to leaching, but it's still not the glossy glaze I am after.
So as I look forward to glaze development, I will be revisiting the Hesselberth and Roy Glossy 1 glaze and pay attention to the cooling rate at the same time I test glazes based on Ravenscrag Slip.
I haven't talked about glaze software, but undoubtedly will in a future post. I am using Digital Fire's Insight software on a trial basis. I'm sure that when my trial ends I will be purchasing it.
First Sale (sort of)
Last fall, my neice asked me if I would donate something for her school's auction. Of course I was flattered and said I would. In January I sent her this set of 3 slab built vases (Laguna ^5 Bmix, Laguna Colonial White glaze fired to ^5). Yesterday, my sister told me that they were displayed at the auction with some silk orchids on the same same table as the Waterford Crystal (I'd like to think there's a logic beyond "just put it over there" to that placement). My sister didn't know the final selling price, but the last bid she saw on them was $100.
At least I now know I'm not the only one who thinks my pieces are worth paying for.
At least I now know I'm not the only one who thinks my pieces are worth paying for.
Tuesday, June 07, 2005
First Sale Display
My next door neighbor, "Cedar" Caredio is a talented woodcarver as well as friendly individual. He belongs to a group called Oregon Crafted which publishes a guidebook and sponsors artitst studio tours on the first weekend of every month. Cedar was kind enough to let me display some of my jellyfish beside his carvings. So I took him up on the deal.
Sunday, June 05, 2005
Am I Really a Potter?
I have been doing pottery as a hobby for eight years and have thought often when I could legitimately call myself a potter. This weekend, as I was putting prices on pottery jellyfish I made for an artists’ home gallery event, it occurred to me that if I was selling pottery I made, I was probably a potter. Now all I have to do is for someone to buy something and I will feel that I am justified in calling myself a potter.
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