- March 2, 2013 at 2:30 pm #9943
Hello – I’m a newbie with 2 weeks of reading and zero classroom time. I’ve spent hours researching and watching videos and searching for information on glass fusing, specifically dichroic jewelry. I’ve made a few pieces so far but have not actually “finished” them out. They’ve been fired and nothing else. My biggest problem with them so far is that the edges are rough. The top clear layer doesn’t flow over all the edges cleanly. So here are some questions:
1. Should the top layer be the exact same size as the the bottom layer or slightly larger?
2. Can I refire these pieces and smooth this out or should I grind/sand them first and then refire? Do I add another layer of glass?
3. When I refire – is the firing schedule the same except for ramp up – just go slower?
4. With dichroic glass – if I have a piece that has a black back – do I have to put it on top of a base or can the back of the dichroic piece be the back of the final piece?
5. And lastly (for this post :0)..) if I want to create a dichro piece with layers…do I create the first piece (usually with a dark base and then chosen black backed dichroic pieces) with a clear piece on top and then fire it? Then on the second step layer the clear dichroic glass and another piece of clear on top? I’m not clear on how to achieve that layered look I’ve seen online that I love. Or do I put it together like this: base + dichro bits/pieces on black + clear dichro piece (with dichro sides not touching) + clear top base? I’m thinking I have to fire twice to achieve that layered look, but want to make sure.
Okay, I’ll leave it at that. These are my most basic questions at the moment and any expert advice will be greatly appreciated. I’ve read and read and read and been able to answer most of my questions – but I’m ready to dig into this new “craft” and need these questions cleared up before I start this next phase.
Thanks so much!
RonJonMarch 2, 2013 at 3:13 pm #12870
I don’t know that my opinions are “expert”, but I’ll try to answer a few anyway .
I think the biggest problem you are having is that you are not firing hot enough or holding long enough. The more heatwork the glass experiences, the smoother and more rounded the edges will be. So…
1 – Yes Some people cut the top piece slightly larger to ensure that it folds over the edges. However, if you think about how the glass will flow, it’s not necessarily required. The glass touching the shelf will flow less than the glass on top. With two layers of glass, this difference in flow is minimal. With more (undammed) layers, it will be more pronounced.
2 & 3 Again, yes . You can refire, or, you can coldwork (grind or sand and then polish). It depends upon the look you are going for. If you want rounded edges, I would simply refire. Because these are small pieces, you are likely safe with your original firing schedule (though you don’t say what that is). If you want squared off edges, you can coldwork to a high polish, or coldwork to a rough finish and then fire polish in the kiln. (good book for beginners – Cold working without Machines http://coldworkingglass.com/).
4 (and 5) A basic tenet of fused glass is that “glass wants to be two layers thick”. So… if you stack two layers, the piece will be roughly the same size when it comes out of the kiln. If you fire one layer, the glass will still try to round up to be two layers thick. What you’ll end up with is the sides pulling in (this is affectionately referred to as “dog-boning”). Conversely, anything stacked thicker than two layers will spread if subjected to sufficient heat work. You can allow the glass to flow, or you can use means to dam the glass so that it doesn’t flow. This layered look you refer to is typically achieved by stacking glass, damming, and then firing. You can also do it two layers at a time, but once you stack additional layers on two, you’ll likely want to dam it to control the flow. For pieces like this, you can make pattern bar “slabs” (I’ve posted one of my pattern bar projects here: http://jestersbaubles.blogspot.com/2013/02/2013-magless-exchange-stained-glass-look.html) You then cut up these slabs into the size of cab you want.
I hope this helps to get you started. The best teacher is experience. You might want to start with less expensive glass (dichro is expensive!), and practice with that.
have fun, Dana
Jester’s Baubles Fused Glass DesignsMarch 2, 2013 at 3:26 pm #12871
One thing I will point out…
In the blogpost I referenced above, I sliced the pattern bars 1/2″ thick then placed them on their “sides” and fired undammed to allow them to spread out. In your case, you would want to layer with the black on the bottom, then layers or clear and dichro. Then, you would slice into the finished size you want. You would not fire the pieces on their sides. In my project, the “viewing angle” of the pattern was from the side, but yours would be from the top.
I doubt what I said just made sense….(she says sheepishly)
Jester’s Baubles Fused Glass DesignsMarch 3, 2013 at 3:54 pm #12872
Thanks so much Dana for your reply. I understand completely what you are saying. I will definitely go and look at the references you listed and do some research on damming. I did purchase an Inland grinder and am looking into some glass breakers as well. The pieces I’ve made so far are quite thick and cutting them has been challenging. I’ve practiced on a few of my “experimental-not so great” pieces and one I was able to break although not straight and the other one…well lets just say I mutilated it. I won’t touch my good ones until I figure this out because I actually like them and want to complete them.
There was only one thing from my original list that I was not exactly clear on from your post – can my dichro pieces (whether thick or thin) if they have a black backing – can that be the base bottom or does it have to be put on another piece of glass. My preference is for the piece to not be so thick and if I’m able to use the full piece of black-backed dichro as the bottom layer (in instances where I’m not cutting and designing) and not have to add that extra layer – I’d like to do that. However, all my research shows/tells you to put on top of a base layer (i.e. black, clear, colored glass, etc.)…You’re right dichroic glass is expensive – so I don’t want to experiment with what I have – I thought I’d just ask. I did purchase 10 lbs of scrap glass so I have plenty of regular glass to play around with.
Some of the things that I’ve purchased is a small Skutt Firebox 8 kiln which is a pretty awesome little kiln I have to say. I researched for days before I bought it and bought it knowing that I would eventually go back and get a controller. After using my kiln 3 times now – I wish I had invested in the controller from the beginning…whew! Nothing like babysitting a kiln for hours. The pyrometer is great, but it would be nice to program and walk away! I also purchased the Contemporary Fused Glass book by Brad Walker and following his firing schedule which is a slow ramp, then bubble squeeze, then fusing (which this is where I think I’m messing up because I’m not leaving it here long enough because the edges aren’t smoothing out) then annealing and cooling. I think I get nervous at the fusing stage because I’ve read this is where you can mess your piece up so to watch it closely. So – should I leave it longer since the common thread throughout the few pieces I’ve done is that I have raw edges on all pieces? My notes say to hold at this stage for 10 minutes (1450 to 1500 degrees)..do you have any suggestions?
Okay, I’ve typed a novel…I’m just so excited to get these last few questions answered so that I can play. Thanks again Dana! I can’t wait to see your response!
RhondaMarch 5, 2013 at 3:18 am #12873
Yes, the dichro with a black backing can be the bottom layer. Even a clear backing can be the bottom layer. Obviously, you’d want to cap with clear
What I answered indirectly in regards to the black being the bottom layer, is that you don’t want to fuse a single layer of black dichro on its own. You’ll want to cap it — otherwise, the dog-boning occurs, if you take to full fusing temps.
Your best bet in cutting thicker pieces is a tile saw with a diamond blade made for glass, if you have access to a tile saw (and have the approx $75 for the blade).
10 minutes at 1450 should be hot/long enough in most instances, but realize that the firing schedules provided in books are a starting point. A kiln could heat hotter or colder than what the thermocouple or pyranometer reads. The second best thing for a kiln, besides the controller, is a view window (IMO). It’s nice to be able to peek in and see what is going on, without opening the kiln door.
Jester’s Baubles Fused Glass DesignsMarch 8, 2013 at 1:08 am #12874
Thanks so much for all your help! I’ll print this out! You’ve been GREAT!
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