Tekta and Fiber Paper

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JenniferB
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Tekta and Fiber Paper

Post by JenniferB »

I know some people, including me, have found a haze on Tekta after firing on Thinfire. I wondered if anyone had had any problems with fiber paper or is this an entirely different product? I want to fuse a plate with pattern bar slices in the center and a border of 6 mm Tekta. I'll fire directly on the shelf which has fresh kiln wash on it and the dams are kilnwashed too, but I've put a 6mm band of fiber paper between the edge of the Tekta and the dams. Am I likely to find devit when I open the kiln? I don't want to use any spray as this plate will probably be used for food.

Jennifer
Brock
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Re: Tekta and Fiber Paper

Post by Brock »

JenniferB wrote:I know some people, including me, have found a haze on Tekta after firing on Thinfire. I wondered if anyone had had any problems with fiber paper or is this an entirely different product? I want to fuse a plate with pattern bar slices in the center and a border of 6 mm Tekta. I'll fire directly on the shelf which has fresh kiln wash on it and the dams are kilnwashed too, but I've put a 6mm band of fiber paper between the edge of the Tekta and the dams. Am I likely to find devit when I open the kiln? I don't want to use any spray as this plate will probably be used for food.

Jennifer
I made dozens, hundreds of plates and sushis exactly that way without any haze.
However, often I F&F after sandblasting and just use KWed dams for the final fire polish.
JenniferB
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Re: Tekta and Fiber Paper

Post by JenniferB »

Thanks Brock,

Now can I ask why you dam the piece when you firepolish it? I wouldn't have thought it would move enough at FP temperatures to require damming. When the first fusing is successful, I usually just coldwork the edges up to 400 grit on the wet belt sander and then fire polish flat on the kiln shelf (with Thinfire if I'm not using Tekta).

Jennifer
Morganica
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Re: Tekta and Fiber Paper

Post by Morganica »

Some people get the hazing with fiber paper (not just thinfire, and not just Tekta), some don't. I get the hazing with fiber paper, don't particularly care since I almost always coldwork the piece pretty extensively either going into the final firing or after I'm done. It may also have something to do with your kiln practices; I fuse in the same kilns I'm casting in, and that really can outgas and cause devit issues, at least in soda lime glasses. It's entirely possible that I've already got crud in the kiln and there's enough coming off the fiber paper to "enhance" the effect.

I just don't use fiber in the final firing and it minimizes any problem for me. Other people vent to allow any outgassing to escape the kiln and not stick around on the glass, and say that works pretty well.

There's a fair amount in the archives about it (or used to be--not sure how much of the old archives have been recovered).
Cynthia Morgan
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Brock
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Re: Tekta and Fiber Paper

Post by Brock »

JenniferB wrote:Thanks Brock,

Now can I ask why you dam the piece when you firepolish it? I wouldn't have thought it would move enough at FP temperatures to require damming. When the first fusing is successful, I usually just coldwork the edges up to 400 grit on the wet belt sander and then fire polish flat on the kiln shelf (with Thinfire if I'm not using Tekta).

Jennifer

Yeah, good question. I'm actually not just FPing. i'm going to another full fuse, and these pieces can be 1/2' thick or more and I want to keep the shape. I found FPing after sandblasting sometimes left tiny pock marks. The smaller the hole or mark, the more heat is required to smooth it out.
JenniferB
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Re: Tekta and Fiber Paper

Post by JenniferB »

Brock wrote:
JenniferB wrote:Thanks Brock,

Now can I ask why you dam the piece when you firepolish it? I wouldn't have thought it would move enough at FP temperatures to require damming. When the first fusing is successful, I usually just coldwork the edges up to 400 grit on the wet belt sander and then fire polish flat on the kiln shelf (with Thinfire if I'm not using Tekta).

Jennifer

Yeah, good question. I'm actually not just FPing. i'm going to another full fuse, and these pieces can be 1/2' thick or more and I want to keep the shape. I found FPing after sandblasting sometimes left tiny pock marks. The smaller the hole or mark, the more heat is required to smooth it out.

Ok, I think I understand. But does this mean you fuse it once, then coldwork, sandblast, and 'flip and fire' again at full fuse temperatures, then firepolish, then slump, meaning 4 trips through the kiln not counting the first one to form the pattern bars?
I've also found tiny 'pits' in the surface after sandblasting but I haven't gone back to full fuse temperatures. I guess I'll have to try that next. But doesn't the second full fuse cancel out the reason you flip it (presuming you're flipping to get the sharper pattern lines over onto the top side)?

Jennifer
JenniferB
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Re: Tekta and Fiber Paper

Post by JenniferB »

Morganica wrote:Some people get the hazing with fiber paper (not just thinfire, and not just Tekta), some don't. I get the hazing with fiber paper, don't particularly care since I almost always coldwork the piece pretty extensively either going into the final firing or after I'm done. It may also have something to do with your kiln practices; I fuse in the same kilns I'm casting in, and that really can outgas and cause devit issues, at least in soda lime glasses. It's entirely possible that I've already got crud in the kiln and there's enough coming off the fiber paper to "enhance" the effect.

I just don't use fiber in the final firing and it minimizes any problem for me. Other people vent to allow any outgassing to escape the kiln and not stick around on the glass, and say that works pretty well.

There's a fair amount in the archives about it (or used to be--not sure how much of the old archives have been recovered).
Cynthia,
Thanks for your comments. I don't cast so I can't blame it on that. I do occasionally get haze or devit on certain glasses (ie Bullseye cobalt blue when I use it on-edge) but I know now that this is going to happen so I avoid using these colours if I can.
I don't use any fiber when I'm firepolishing or slumping, it's only during the full fuse phase that I've had hazing on Tekta.
When you refer to venting the kiln, I'm assuming you mean passive venting - just keeping the peephole open - rather than actually drawing air out of the kiln the way potters do?
Jennifer
Morganica
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Re: Tekta and Fiber Paper

Post by Morganica »

Passive for now, yes, although I don't just open the peepholes, I crack the kiln lid on the bathtub kiln by a good 2-3 inches. I'm looking into an active ventilation system for the whole studio--I've literally rusted out half my garage with the passive--so that will change.
Cynthia Morgan
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Valerie Adams
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Re: Tekta and Fiber Paper

Post by Valerie Adams »

I've all but eliminated using Thinfire because of the scummy haze on Tekta, and have seen improvements. My issues only started with my Tekta use.

Bullseye continues to blame cleaning techniques but I don't have the problem with any glass besides Tekta, and I clean all my glass in the same manner. I've replaced all my cleaning cloths, use Spartan cleaner like Bullseye recommends, scrub each side of glass with a clean, fresh towel, etc.

The ONLY thing I haven't done is dry my cloths outside on a clothesline, which will be my next tactic. Someone pointed out that even though I don't use fabric softener with my shop towels, they are dried in a dryer that clothing is also dried in, and I use fabric softener on clothing. It's a stretch, but I've exhausted all other variables.
Brock
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Re: Tekta and Fiber Paper

Post by Brock »

Yeah, good question. I'm actually not just FPing. I'm going to another full fuse, and these pieces can be 1/2' thick or more and I want to keep the shape. I found FPing after sandblasting sometimes left tiny pock marks. The smaller the hole or mark, the more heat is required to smooth it out.

Ok, I think I understand. But does this mean you fuse it once, then coldwork, sandblast, and 'flip and fire' again at full fuse temperatures, then firepolish, then slump, meaning 4 trips through the kiln not counting the first one to form the pattern bars?[/i] I've also found tiny 'pits' in the surface after sandblasting but I haven't gone back to full fuse temperatures. I guess I'll have to try that next. But doesn't the second full fuse cancel out the reason you flip it (presuming you're flipping to get the sharper pattern lines over onto the top side)?

Okay . . . make the PB.
Then arrange, border, dam (with fiber paper) and fire face down on a clear base.
Anneal, roughly cold work, dam (without fiber paper) and full fuse. *
Anneal, cold work and slump.
Sell and retire . . .

* At this stage I used 1/16" plastic spacers (which I remove before firing) to allow the blank to flow OUT to the dam. No needles, reduced cold work required. Fill your kiln, I used to make at least 6 at a time. Spend a couple of days making mesh melt, pot melts, groovy puddles, then cut them up for components. Cut them roughly 1/4" thick so that you can make a 2 layer (overlapping) border.

Here's a simple formula for 2 layer borders:

Let's say your arranged PB insert measures 5" x 7" and you want a 1" border.
You need 8 pieces of your border glass in 1" strips, 4 pieces 6" long and 4 pieces 8" long.
You also need a clear base 7" x 9", ( this works for any increment you desire).


Place the clear base on the shelf and make a right angle of dam material, lined with strips of fiber paper, on your kiln shelf. Leave the fiber paper slightly long for trimming later. Buttress the dam material if necessary. Lay out a short (6") and a long (8") border piece, flat, meeting in a right angle at the corner, on top of the base.
Arrange the PB insert on the clear base, butting up to the border strips.
Lay the other 2 border pieces on the base and finish damming, with fiber paper and dam materials.
Lay the second row of border strips OVERLAPPING the joints if the first row.
Use an X-acto knife or thin tool to even the PB insert out, making gaps, if any, the same width.
When constructing the border, if there are gaps push everything tight to the PB insert, making any irregularities on the outside perimeter, (where it can easily be coldworked later).

It's a lot easier to show this than describe it . . .
JenniferB
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Re: Tekta and Fiber Paper

Post by JenniferB »

Valerie Adams wrote:I've all but eliminated using Thinfire because of the scummy haze on Tekta, and have seen improvements. My issues only started with my Tekta use.

Bullseye continues to blame cleaning techniques but I don't have the problem with any glass besides Tekta, and I clean all my glass in the same manner. I've replaced all my cleaning cloths, use Spartan cleaner like Bullseye recommends, scrub each side of glass with a clean, fresh towel, etc.

The ONLY thing I haven't done is dry my cloths outside on a clothesline, which will be my next tactic. Someone pointed out that even though I don't use fabric softener with my shop towels, they are dried in a dryer that clothing is also dried in, and I use fabric softener on clothing. It's a stretch, but I've exhausted all other variables.
Valerie,
I've had the same results with Tekta compared other glasses and I can't believe that those of us who've had hazing issues don't clean just our Tekta poorly and the rest of the glass we use well. I will continue to use Thinfire because I like the smoother surface it leaves on the underside so my next step is probably to use Uroboros whenever I want a clear glass. I've used it with Bullseye with no problems at all in many different projects. The very small risk of incompatibility is far outweighed by the guaranteed irritation and almost certain extra work when a piece comes out if the kiln with haze.
Jennifer
JenniferB
Posts: 61
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Re: Tekta and Fiber Paper

Post by JenniferB »

Brock wrote:Okay . . . make the PB.
Then arrange, border, dam (with fiber paper) and fire face down on a clear base.
Anneal, roughly cold work, dam (without fiber paper) and full fuse. *
Anneal, cold work and slump.
Sell and retire . . .
* At this stage I used 1/16" plastic spacers (which I remove before firing) to allow the blank to flow OUT to the dam. No needles, reduced cold work required. Fill your kiln, I used to make at least 6 at a time. Spend a couple of days making mesh melt, pot melts, groovy puddles, then cut them up for components. Cut them roughly 1/4" thick so that you can make a 2 layer (overlapping) border.
Here's a simple formula for 2 layer borders:
Let's say your arranged PB insert measures 5" x 7" and you want a 1" border.
You need 8 pieces of your border glass in 1" strips, 4 pieces 6" long and 4 pieces 8" long.
You also need a clear base 7" x 9", ( this works for any increment you desire).
Place the clear base on the shelf and make a right angle of dam material, lined with strips of fiber paper, on your kiln shelf. Leave the fiber paper slightly long for trimming later. Buttress the dam material if necessary. Lay out a short (6") and a long (8") border piece, flat, meeting in a right angle at the corner, on top of the base.
Arrange the PB insert on the clear base, butting up to the border strips.
Lay the other 2 border pieces on the base and finish damming, with fiber paper and dam materials.
Lay the second row of border strips OVERLAPPING the joints if the first row.
Use an X-acto knife or thin tool to even the PB insert out, making gaps, if any, the same width.
When constructing the border, if there are gaps push everything tight to the PB insert, making any irregularities on the outside perimeter, (where it can easily be coldworked later).
It's a lot easier to show this than describe it . . .
Brock,
You've actually explained it beautifully. Thank you. Now just one more question. You seem to be making your piece about 9mm thick, with the clear base(presumably 3mm), 1/4" (6mm) PB slices and two 3mm layers for the border. Would it work as well just using the clear base, 3mm PB slices and 1 layer for the border?
Jennifer
Brock
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Re: Tekta and Fiber Paper

Post by Brock »

Nope. You need 2 border layers to cover the butt joints, otherwise you can see them easily.
JenniferB
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Re: Tekta and Fiber Paper

Post by JenniferB »

Brock wrote:Nope. You need 2 border layers to cover the butt joints, otherwise you can see them easily.
Oh yes! Of course! That smacking sound you hear is the heel of my hand hitting my forehead!! Thanks again.

Jennifer
sbanthony
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Re: Tekta and Fiber Paper

Post by sbanthony »

JenniferB wrote: Brock,
You've actually explained it beautifully. Thank you.
Jennifer
Yes, a great discussion!

I am curious, Brock, why you add the clear layer. Is it aesthetic or functional? Does it help fill in the gaps and chinks (if there are any) in the PB slices?
thanks,
--SB
Brock
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Re: Tekta and Fiber Paper

Post by Brock »

The clear layer is there for several reasons. Firstly, I like to build on a clear base, it's just easier. If you don't, and have to adjust your PB pieces as you often do, they could pick up KW between the slices. Clear is less prone to sticking to KW than opalescent colors. Also, I flip and fire my PB pieces and the clear, once flipped, adds depth to the piece. It also doesn't devit as much as opalescent colors and therefore has a nicer appearance. Clear is softer than a lot, if not all, opalecents, so it is easier to cold work.
Morganica
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Re: Tekta and Fiber Paper

Post by Morganica »

Another reason to use clear: It puts a layer between you and potential bubbles, giving you plenty of room to grind all the way to flat (or to shape a particular profile) without breaking through bubbles and making pinholes in the top of your piece.
Cynthia Morgan
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"I wrote, therefore I was." (me)
JenniferB
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Re: Tekta and Fiber Paper

Post by JenniferB »

Brock wrote:The clear layer is there for several reasons. Firstly, I like to build on a clear base, it's just easier. If you don't, and have to adjust your PB pieces as you often do, they could pick up KW between the slices. Clear is less prone to sticking to KW than opalescent colors. Also, I flip and fire my PB pieces and the clear, once flipped, adds depth to the piece. It also doesn't devit as much as opalescent colors and therefore has a nicer appearance. Clear is softer than a lot, if not all, opalecents, so it is easier to cold work.
Brock,
I'm curious to know which clear glass you use. Tekta or one of the other Bullseye clears, or do you work with COE 96?
Jennifer
Brock
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Re: Tekta and Fiber Paper

Post by Brock »

Mainly Tekta Crystal Clear or Bullseye Clear, 1401 I think?
JenniferB
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Re: Tekta and Fiber Paper

Post by JenniferB »

Brock wrote:Mainly Tekta Crystal Clear or Bullseye Clear, 1401 I think?

Thanks. There's a Crystal Clear Tekta that's 1401-0380 and a Crystal Clear that's not Tekta that's 1401-0030. There's also a Clear Transparent Tekta that's 1100-0030 (I think) and a Clear Transparent non-Tekta that's 1101-0030. I may test out one of the non-Tekta glasses to see if that presents fewer problems. I also found, in the same PB plate that had the haze, that the Tekta didn't seem to fuse completely and I fired to 1500 with a good soak (I don't have my log book in front of me). I think that would have been plenty to completely fuse 6mm of most other glasses.

Thanks for all this information. I've learned a lot and appreciated your sharing.

Jennifer
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