Just a quick post to share one of my new favorite pieces. I wanted to step up the content and interest level of my vases so I pieced together multiple glass components, fully fused them, and then draped them to form this glittery vase.
Yes, I used some iridescent blue glass along with my more traditional black and white opaques. The blue and purple colors are actually the same glass. One side has a thin metallic layer sputtered onto the surface of transparent blue glass (don’t ask me to explain sputtering – that’s actually a key process in my day job and I can wax eloquent for days). I cut squares and other shapes from this iridescent blue glass and then fused some ‘face up’ and some ‘face down’ so the metal layer exposure varied. When the metal layer faces ‘up’ it creates that glittery, metallic purple sheen. Pretty snazzy!
Here’s another viewpoint of the vase.
When I did my first flat full fuse, I really focused on creating a geometric shape. It was very satisfying and somewhat lucky that the second slump fuse allowed the melting glass to drape along the pattern.
I had to share these pics since I’m not ready to part with this particular vase and put it up for sale. It gets a shelf in my house for now.
Fig 1. My first 3 Drop Out Vases
In this instance, I was ready to try a new technique in glass fusing. I wanted to make a different kind of vase, other than a draped handkerchief style. I had seen pictures of cool vases that looked thinner with truly cylindrical walls but didn’t know how to make them. So began my intro to dropped vases.
With a dropped vase, you start with a thick flat sheet of glass and suspend it over a ceramic ring (circular or square) that has a hole in the middle. (The ring needs to be on stilts above the kiln shelf) Heat the glass up in the kiln to around 1330F. The center of the glass will slowly drop down through the ring. This creates the basic vase form.
Now for some details…
The general rule of thumb is that every 3 mm of glass can drop ~2 inches. Knowing this, my first attempt used 2 layers of 3mm glass. Base layer was a 8″ clear plate. The top layer was a mix of blue and purple segments along with some grape frit to fill in any gaps.
Fig 2. Glass segments laid out before full fuse.
I did a standard full fuse sequence (to 1460 F) to fuse this into one thick glass plate.
Now I was ready for the drop out phase. I propped the 8″ glass disc on my ceramic ring with a 4″ center hole. Since my glass was 6 mm thick, I theoretically could allow for a 4″ drop. However, I was very nervous and opted to only use 3″ posts. I was afraid my glass would drop too much, thin too much, and actually collapse or open a hole in the center.
Fig 3. Set up in kiln before drop fuse cycle.
For my first attempt, I only went to 1300F and held for 15 minutes. I was peeking into the kiln quite a bit. I discovered it was really hard to tell how far down the glass was drooping. Was it hitting the kiln shelf? Once you think it’s dropped enough, you need to drop the temp as fast as possible to an annealing temp of ~950F. If you hold at high temps, the glass will continue to melt and let gravity do its thing. To speed the cooling, I opened the kiln top several times until the temp was down to around 1100F. I did find out that even Kevlar gloves will start to singe if you hold them near the kiln opening too long! A bit too toasty for my comfort.
Fig 4. The final product placed in an iron stand.
Once everything was cool, I was able to see that I freaked out too soon. The glass had dropped but not enough to really hit the kiln shelf and form a flat base. That’s ok. I had a nifty iron candle stand I pressed into service. You will also note that the vase lip is rather wide and has dimples. To support the weight of the dropping glass, the lip on all molds will tend to be wide. My particular mold had small holes throughout the lip to add additional dimension (or dimples).
That was fun! Let’s try again.
Round 2 featured 3 layers of fully fused glass. This thicker starting point was a boost to my confidence that the drooping glass had enough material to drop to the kiln shelf. I used 3″ posts again but went a little hotter, to 1330 F, and held longer, for 20 minutes.
Fig 5. Much better! This vase can stand on its own or in a stand (as shown). It also has enough volume to hold a votive candle.
Now I was ready to really go for it! Last attempt used 3 layers of glass but I boldly used 4″ posts. I was going to let this one drop further.
Fig 6. Finally, a full drop out vase, complete with a foot.
Note that a foot formed by allowing the droop (or slump) to continue beyond the point of initial contact with the kiln shelf. A little longer and things might have gotten dicey. Remember, the foot cannot get wider than the ceramic ring’s hole or you can’t pull the glass vase out!
To succeed in dropping out, you do have to let go of your fears and just go for it. It can be scary but you’ll figure things out. I’m ready to get even wilder – more layers and larger drops.
Yup, that echoed throughout my studio when I checked a kiln run that was ruinous. I had been lured into a compulsive buy at a glass supply store. The specialty glass piece had multi-hued green shards on top of a blue swirled opaque white sheet. I thought it was perfect for one of my organic shaped vases.
During the initial heating process, right around 600 F, I heard a loud noise but didn’t know what it might have been. I wasn’t about to violate the basic rules of fusing glass and look inside the kiln when it wasn’t above 1100 F. When the temperature did reach the expected slumping point (~1200 F), I took a peek. Oh no!
This is what I saw.
The center of the glass had split open and the entire piece had fallen down around the mold instead of slowly draping over it. I think the noise I heard was the glass splitting open. Maybe the glass had not been properly annealed when I obtained it? I used my standard ramp rate for heating the glass – after holding for 15 min at 300F, ramp to 1100 F at 300 F/hour.
This odd glass imitation of a mounted fish (I could only see a big bass mouth mocking me) stumped me for many months. What would I do with it?
Yes. I attacked this with a hammer and smashed this oddity into pieces. I could start over.
Success!!!! I’m happy with how I recovered from one fusing disaster to create something exciting. Perseverance pays.
We’ve been taught to believe that bigger is better. When presented with a draping mold, I always made full use of it. A mold that stands 7″ high should produce a vase that also stands 7″ high. But of course! In fact, I’ve been apologetic that I couldn’t produce larger, more glorious vases due to the size of my kiln.
Imagine my surprise when I got an inquiry about miniature bud vases. What exactly did they want? A tall but narrow vase? A short vase? And more importantly, what could I actually make? I had never considered my options.
Let’s start with the draping molds or so-called floral drapers I had access to.
On the right is a mold which stands 7″ tall with a top (the final vase base) that is 2.5″ in diameter. On the left, is a stainless steel pillar also 7″ tall but with a narrower 1″ diameter. Both have been coated with boron nitride (MR-97) which is a glass mold release and makes the shiny stainless look white.
All my previous vases started with a 12″ sheet of glass that would drape around the mold at elevated temperatures and produce a 7″ tall vase. (See my previous post https://geekgirlglass.com/2013/10/19/feeling-the-heat-temperature-dependence-of-draping-vases/) . My obvious first attempt to shrink a vase was to repeat the process but starting with a 8.75″ sheet of glass with rounded edges. The result was a funky, short fat vase that stood 5″ tall.
How about using the 1″ diameter floral draper? I went with a 6″ square of rose colored transparent glass. (Yes, I kept decreasing my starting glass size). That ended up with a 4″ vase with a small 1″ base and rosy’ flames’ creating the sides.
Next attempt used a 7″ circle draped over the 2.5″ form. I played with blue frit on the border and confetti glass pieces to create a tribute to Mondrian. This ended up more like a bowl than a vase. Total height = 2″.
Fourth variation really pushed the limits. Only a 4.5″ circle of glass was draped over the 1″ form. This resulted in a truly petite 2″ tall vase. Perhaps this is only good for holding a few Jelly-Bellies?
Here is the final line-up of vase variations.
As you can see, I have a much broader range of vase options than I thought. I had a blast pushing the limits of down-sizing with this project. In the end, I must agree with Mies Van der Rohe. Yes, ‘less is more.’
One of my first exposures to fusing glass involved a very simple class where we selected 1 sheet of glass, cleaned it, figured out the center, and placed it over a form in the kiln. The instructor worked some kiln magic and after several hours invited us to peer into the kiln to see how the flat sheet of glass had begun to fall around the form. (This is technically draping and not slumping glass).
How cool! Was it really that easy to make beautiful glass vases? I didn’t know enough to realize what factors played a role in creating the magical whimsical handkerchief forms. Nevertheless, like a junkie’s first hit, I was hooked.
Yes, the instructor muttered under her breath about the danger of over-firing the glass and actually getting the mold stuck within the glass and having to destroy the glass and even the mold but who was listening? This post will not auger into disaster scenarios, though. (There is plenty of time for examples later…).
With time, I have begun to see the versatility possible with creating vases. Obviously one can fuse many pieces together to create a 2D sheet that is far more complex and exciting than a single color sheet of glass like I was first exposed to. Another Boulder artist, Bobbi Vischi (www.bobbivischi.com), takes this to an awesome level.
The key to the final shape all comes down to temperature. I have conducted a experiment creating vases that have been taken to different slump temperatures. Remember, glass most soften and begin to melt. The amount the glass ‘melts’ is temperature dependent. The glass will first seem to fold along one axis creating what is affectionately known as a ‘taco’ (or is it because this always seems to occur at lunch time during classes?). As the temperature is increased, the glass moves more and additional folds are created. At higher temps, the glass really begins to take on the form of mold it is draping over. Go much further and you are risking it all.
‘Don’t forget time!’ you may say but that seems almost secondary to the ultimate heat the glass is exposed to. At low temperatures, even if I hold for an extended period of time, I can’t seem to move much beyond the taco shape.
Pictures tell the story the best. In all cases, the kiln firing schedule was as follows:
Ramp 150F/hr to 300F and Hold for 15 minutes
Ramp 300F/hr to 1100F and Hold for 20 minutes
Ramp 150F/hr to SLUMP TEMP and Hold for X minutes
Cool 400F/hr to 950F and Hold for 1 hour
Cool 150F/hr to 800 and Hold for 10 minutes
Example 3: 1225F for 1 min (about as far as want to go)
Now back to experimenting with my vases….