Week 4 (Week Beginning 15/02/10) Continued

Kiln Casting

At the start of week 3 I made a mould to make Sven a twin brother, but not an identical one. When I made the mould I made some space of excess glass by sitting the piece on some rolled out clay and cut around the edges to continue the shape and because the last one I did, I had to spend some time flat bedding the piece so it could be could on the glass band saw. This way I would have to do as much cold working and if I needed some glass cut off I could get it done faster. I used the same mould mix of Plaster, Silica, HT and water but I ended up having to get some more mould mixture after I had poured because I had made the walls around the mould slightly wider than I did the last time. When the mould had dried long enough so I could take away the walls I cleaned up the mould and removed the wax and clay using some tools. When I was happy the mould was clean enough I put the mould in the drying cuboard and left it there until Friday. I wanted to see if I could get more of the copper colour in the glass (without buying the Light Copper Oxide colour of the Gaffer Casting Crystal, which I am considering getting for my final piece of work) so instead of just sieving the copper oxide in I just tipped a load in (I know very technical) then brushed it around the mould to cover all the surfaces, I wanted to put some into the flowerpot reservoir I was using but I've done this before and it makes an orb of colour in the middle of the piece (not really what I wanted). Instead of doing a displacement test I took Sven and weighed him on some scales, he was about 680g. Then I weighed out 680g of glass but it didn't look like very much compared to the size of Sven, so I put and extra 100g in because I thought about hown I had needed to cold work the piece so I'd taken some weight off (not 100g but its better to have more than you need compared to not enough). When I had set every thing up, put the glass in to the flower pot and set up some pieces of kiln shelf to rest it on and put it in the kiln to cast over the weekend. But unfortunately someone must have opened it and forgot to turn it back on or I was a bit of a plum and forgot to turn it on - but I am very sure I turned it on. Anyway when I came in on Monday morning to see how the cast was going I discovered my glass set up just as I had left it (cold and un melted). So I locked the kiln and turned it on checking it repeatedly to check no one was trying to mess with my head....

Here is the kiln program I used:

100 ⁰C/hr → 550 ⁰C → Pass hrs
Full ⁰C/hr → 880 ⁰C → 11.00 hrs
(held longer to try to get rid of bubbles)
Full ⁰C/hr → 520 ⁰C → 15.00hrs
10 ⁰C/hr → 300 ⁰C → Pass
20 ⁰C/hr → 100 ⁰C → Pass
End

And here is how the piece looked when int came out the kiln:

After looking at this piece I'm starting to lean towards using coloured casting billets to get a consistent colouring throughout the piece, but I could still use copper oxide with the billets to add a bit more colour and detail to the pieces. Not sure yet though, especially as I have moved on to make my forms with a mixture of surface textures.


Gelflex Mould

In my last post I had started to develop a plaster modal with a mixture of curvy flowing surface to contrast the geometric form. I have decided that I want to see how this will look in glass so I flatted off the straight edges but hand laping the plaster against a sheet of sand blasted sheet glass and used sand paper to smooth out the curvy surface ready to make a gelflex mould of it.
When setting up my piece of plaster I sat my piece of plaster on a rolled out sheet of clay and cut around it to leave me with a bit of over flow when pouring wax after the gelflex is made and it will provide the overflow for my investment moulds. When I was waiting for the gelflex to melt I used a spray bottle to keep the plaster damp so the plaster doesn't stick to the gelflex.
The gelflex I used for this mould was my old one I had for making brothers for Sven, and after that had been melted it didn't look like i would have enough so I managed to find out an old gelflex that I had forgotten about to cut in to tiny chunks to put into the melting pot. I started heating the gelflex at 150⁰C but it was taking a long time for the gelflex to start melting even with the lid on so I turned it up to 165⁰C that seemed to work a lot better. It took around 2hrs to melt completely. When the gelfex had melted I turned off the pot and left it for just over 30mins and stirred it regularly. I think I may have poured it a little too soon there were a few bubbles rising to the surface, especially near where the point at the top of the plaster is. I usually leave gelflex to cool for around 45mins but in some of my moulds haven't picked up all the detail and there have been streaks in the gelflex, this is why I poured it earlier.
Didn't seem like too bad a mould but I'll have to wait until the mould has cooled completely so I can take the plaster out and have a look, and then I can go on to make a wax from it and see how my new form will look in glass. This wont be my final piece, it's just a test to see how the contrasting surfaces work together. I really want to see how the curves look when looking through the glass on the other side of the piece.
Also really proud because Mark our plaster technician (and a legend) commented on how beautiful the piece was *Happy Kimi*


Random Photo

Can't remember taking this photo, but I really like it...

"Hello Feet"

Week 4 (Week Beginning 15/02/10)

Plaster Models

(In Week 3) After attempting to re make my shape using my rubbish gelflex mould I have chosen to make some new shapes using the band saw to cut up some chunks of plaster, like I did originally to make the shape I've been working with a lot. Going to keep with a similar shape as I'm quite fond of triangles at the moment, so at the end of last week I made a couple of plaster triangle shapes to cut more 30cm and I needed it to be 13cm deep (I tried 2 times the size but that seemed like it would be a bit too big and After attempting to remake my plaster shape by using my rubbish gelflex mould I have chosen triangles shapes out of, I tried to make them by measuring a right angle triangle that was 1.5 times as big as the original shape making it 19cm x 23cm, the hypotenuse difficult to cut on the band saw, also if I was to make it out of glass it would be too expensive just for testing). As I am not used to working with just plaster (when working with plaster, silica and HT the amount of water is measured in liter, and just working with plaster the water is measured in pint) I estimated at I would need 4 pints of water and about 2.75kg of plaster after I set up my mould and I mixed and poured in the plaster the mould collapsed, I managed to pull it back together with a little help but it there wasn't enough plaster to get up the 13cm in depth, so I tried again with the same amounts of plaster unfortunately as the last mould had spilt I didn't find out if there was enough plaster to get to the 13cm point on the inside of my mould. But fortunately this time there were no spillages.

(Now in Week 4) I have started working on cutting out some new triangular shapes and working on some organic flowing surface decoration/texture. To make the texture on the piece below I just stared carving into the plaster with ceramics and wax carving tools to give a nice organic flowing type of efect. My original idea was to make gelflex of an interesting piece of wood then amke a wax of it, pour plaster over the top to make a block to cut out on the band saw then to melt the wax out to give the imprint of the wood. I may still do this but I really like the texture I have created.

Week 3 (Week Beginning 08/02/10)

Plaster Models

On the left is an image of the gleflex mould I made last semester of a plaster form I had cut and smoother out. At the end of week 2 I made a wax for lost wax casting from this mould and saw that it was staring to look a bit shabby and I realised I should have cast the gelflex into a triangular shape the fit the shape of the plaster model. As I ended up flat bedding off a lot more than I would have liked to on my kiln cast glass piece of the same shape I wanted to try to re make the mould, so I decided to pour plaster into the mould, now looking back on this I don't think I was such a good Idea because as I have been trying to smooth down the edges and it had taken a lot of time and effort, and I'm still not happy that the edges arn't completly flat. And as I have been polishing down the sides the shape has been getting smaller and I dont think that it looks as good as the original. I have been thinking about trying to make the piece again using different methods, like re cutting the piece on the band saw by measuring out the shape with a little etra to the size to alow for polishing or another idea I've had is to use alginate to take a mould of the glass piece as I'm happy with the shape and flatness of it then use the alginated to make a new plaster model.

Desk Watch (08/02/10)

My desk is looking a lot fuller today, just wanted to share that with everyone.

As you can see I have spent some time doing some drawing and painting (not great one though) and I'm soaking some plaster ready to cut up a new shape on the band saw in the week.

Desk Watch (05/02/10)

Desk at the end of week 2. Still looking a bid naked dispite the new glass editions, could do with some images stuck up of my inspiration. This will be my aim for the end of week 3

Also in the week I made a second investment mould for my arcitectual form, and have booked a kiln for the 11th and over the week end, I'm hoping I'll be able to use the same kiln as last time because I was really happy with the results, may hold the top temperature for an hour or so longer to get rid of those last few bubble, not sure weather to use the copper oxide again although I have been getting a lot of positive feed back off fellow students and staff about the ascetics of the piece. I have worked on making another wax for lost wax casting but as I'm not very happy with how the gelfex turned out last time, I'm planning to make a new gelflex mould and reinforcing it with plaster to make it stronger and so it holds its shape better. I've also made a a copy of the arcitectual shape after the original has been chipped and worn down while I was using it in hot casting and I have put the off cut glass from my kiln cast in a kiln with some copper oxide sprinkled under it, thought it might be a idea to use it to make some related pieces of jewelry.

Week 1 (Week Begining 25/01/10)

Casting Architectural Forms

For this new semester I have decided to carry on with some of the work I started last semester and expand upon what I have already done and taking my inspiration from architectural forms (in particular new and modern architecture like the work of Zara Hadid)
In the first semester I started using the band saw in the plaster room to make shapes cause I was having trouble modeling in card and wasn't able to accurately draw the shapes in my sketch book. After spending some time practicing on the band saw I came up with a couple of shapes I was happy with.
Above is the shape I was most pleased with. After flattening off the sides by using water and hand lapping the plaster against a sheet of sandblasted glass I soaked the plaster ready to make a gel flex mould of it. When the mould had cooled completely I poured wax into the mould and to make a wax duplicate of my plaster model in order to do a lost wax cast. The wax I made was hollowed out so that it wouldn't take too long to get the wax out of the cast (this is where I left off with this piece last semester). On the Tuesday of the first week I made the investment mould for the piece using a mixture of plaster (1.2kg), silica (1.2kg), HT (800g) and water (just over 2lts). When the mould had hardened I cleaned it up and removed the wax (because the wax was hollow I didn't bother steaming it and scraped out a bit of the wax and the rest I was able to just pull out of the mould. The mould was left a few days in the drying cupboard for it to dry completely.

Using a displacement test I found that I would need about 500ml of glass to fill the mould, so I measured out a little more than 500ml of Glasma Glass (from the hot shop) just in case. I then put the glass into a flower pot because the glass wouldn't all fit into the mould. Before putting the glass onto the mould I sieved some copper oxide onto the mould to give the glass a blue colour (this is also carrying on from some of the work I did last semester). I then rested the flower pot on top of some kiln shelf wrapped in ceramic fiber paper so if there is too much glass and the kiln shelf and the glass touch there wont be a compatibility problem.

When I was happy with how everything was set up in the kiln I shut the kiln and set it for a full cast. This is the program I used:

100 ⁰C/hr → 550 ⁰C → Pass hrs
Full ⁰C/hr → 880 ⁰C → 10.00 hrs
Full ⁰C/hr → 530 ⁰C → Pass
10 ⁰C/hr → 520 ⁰C → 11.00 hrs
10 ⁰C/hr → 300 ⁰C → Pass
20 ⁰C/hr → 100 ⁰C → Pass
End

The kiln was set on 29/01/10 I will post an image of how the piece comes out when the program is complete.

Carrying On

I starter on a piece last semester and I wasn't able to completely finish it in time for hand in so this week I have spent some time on it trying to get it polished.

The piece was a lot taller but there were cracks and I didn't want them to run through the rest of the piece. I managed to get a good polish with pumice on the polishing wheel but because of the shape its going to take some time to get to a high polish. There are also some chips in the piece and a large concave area where there was a crack in the mould so the glass much have flowed out as it was cooling, I have been thinking about using the diamond wheel to smooth down these area so they look better and are easier to polish. I was intending to enter this piece to the warm glass award but the lack of technicians has meant I haven't been able to have much time in the cold work shop.

Hot Work

On the Friday afternoon I made a seconded wax of the shape in casting architectural forms, and when I was waiting for it to cool I had planned to do some polishing but no one was in to keep an eye on the cold work shop so I decided to go and do some work in the hot shop, not really aiming to make anything just wanted to practice shaping and see if I could still manage working with hot glass. I took a few gathers but didn't do any blowing because I had a cold sore, so spent a lot of time shaping and re-heating the glass. I didn't keep the piece in the end because I didn't fancy paying for it and it didn't seem very relevant to my work. But after having a chat with Simon (the hot glass technician) about my work he suggested doing hot casts of the plaster pieces I had already made. I haven't done any hot casting before so Simon said he would help me on Monday afternoon to see if I was interested in incorporating it in to my work.