Frit-Happens !
April 23, 2021, 09:36:49 AM *
Welcome, Guest. Please login or register.

Login with username, password and session length
your ad here
News:
Where are you?? Add yourself to the NEW FHF map here  | On flickr? Join our Frit Happens group: here

VISIT THE WIKI HERE
Get FH Status updates via twitter @FritHappens

 
   Home   Help Search Calendar Login Register  
Pages: [1]
  Print  
Author Topic: Float Glass won't fuse  (Read 4990 times)
0 Members and 1 Guest are viewing this topic.
Sharon the Cat
New Forum Member
*
Posts: 6


« on: January 06, 2015, 11:02:37 AM »

Hi, I'm new here & will get straight in with a problem.

I have been experimenting with very basic float glass snowflakes. They are 3mm glass from a window with a copper wire inclusion as a hanger & originally some gold flakes but they fell off!

See pic below.

I like the devitrification because it makes the snowflake look frosty but I cannot get it to actually fuse.

So far I have tried to fire them 4 times, as follows.

1]
Segment   Ramp Rate (F/hour)   Target (F)   Hold (minutes)
1   250   1100   15
2   200   1245   30
3   9999   1510   15
4   9999   1100   35
5   150   900   0

Try 2] holding for 5 more minutes on segment 3

Segment   Ramp Rate (F/hour)   Target (F)   Hold (minutes)
1   250   1100   15
2   200   1245   30
3   9999   1510   20
4   9999   1100   35
5   150   900   0

Try 3]   

Segment   Ramp Rate (F/hour)   Target (F)   Hold (minutes)
1   250   1100   15
2   200   1245   30
3   9999   1520   22
4   9999   1100   35
5   150   900   0
 
4th attempt

Segment   Ramp Rate (F/hour)   Target (F)   Hold (minutes)
1   250   1100   15
2   200   1245   30
3   9999   1550   20
4   9999   1100   35
5   150   900   0

I've cooked them so much the copper wire has burnt through.
My kiln is a Skutt Firebox & I would appreciate any advice from the knowledgeable out there. Smiley
Logged
flame n fuse
Forum Member
****
Posts: 464


WWW
« Reply #1 on: January 06, 2015, 11:40:32 AM »

Hello Sharon
I've never fused float glass, but it sounds as if your programmed temperatures should be within the right range. Have you used this kiln before ? (I'm wondering if the temperatures are reliable).
Logged
Sharon the Cat
New Forum Member
*
Posts: 6


« Reply #2 on: January 06, 2015, 11:59:54 AM »

Yes, I've used it very successfully with both Bullseye & other float projects.

When I tack fused float it took me a few tries to get it right with a certain softness to the edges but this has me stumped.
Logged
silkworm
Forum Member
**
Posts: 71


« Reply #3 on: January 06, 2015, 12:15:28 PM »

With my firebox on its auto fast and full which it states to be 1465 I get a mid fuse on float. Were you wanting a full fuse or are the pieces not sticking together?
Logged

Mary
Zeldazog
My name's Dawn, I'm an
Administrator
*******
Posts: 1048


I'm free, to do what I want...♪♪♪


« Reply #4 on: January 06, 2015, 04:56:31 PM »

I wondered the same as Silkworm - do you mean they're not sticking, or do you mean you want a full fuse?  They look nicely tacked to me?

1550F is 843C which is about what I do a full fuse of float glass at.

Are these pieces that you've re-fired several times?  Or tried different pieces at the different temperatures? 

If they are ones that have been back in several times, I'd guess that they're now beyond re-working, as the devit will probably be doing something to stop it fully fusing together.  Try using the 4th schedule with a new batch.  Or even one on its own if you don't want to waste loads more time cutting lots of snowflakes (kilns cost a lot less to run than you think)

Are you sure it's float glass, did you buy it from a store or could it be from a double glazed window?  If so, could you be working with K glass or E glass, that's a very even de-vit you're getting there otherwise?  Actualy, for float, it looks very 'water white' float normally shows quite a green tinge - is it possibly Optiwhite, which I've never tried working with but I wonder if it fires differently due to it's altered formula?



Logged

Zeldazog
My name's Dawn, I'm an
Administrator
*******
Posts: 1048


I'm free, to do what I want...♪♪♪


« Reply #5 on: January 06, 2015, 05:02:44 PM »



Although this was only tack fused, I find it very difficult to get a full fuse to the treated side of Pilkington K/Planibel E glass (to the point I stopped trying)
Logged

Sharon the Cat
New Forum Member
*
Posts: 6


« Reply #6 on: January 07, 2015, 02:48:15 AM »

Some good points there, thanks to everyone who responded.
To try and answer all points in one go.

When I said fuse I meant full fuse not tack fuse. As I mentioned I have tack fused float glass no problem & these are most certainly tacked, sorry I thought you could see this in the photo.

All pieces fired 4 times. I was wondering if the devit somehow was holding the form so that it couldn't draw up properly.

I've looked back at my records & the first fuse was in fact a tack fuse because I needed another piece of float tacked urgently. There was no devit after tack fuse & they were tacked OK.

The second firing was supposed to be a full fuse & this is where the devit appeared. The devit seemed to increase with each firing.

I have no idea what the glass was originally, it could have been window, greenhouse or double glazing, but I doubt if it was Pilkington K. The original pieces of glass did have the green tinge to the edges.

When I first tack fused float it took 4 attempts for the edges & points to soften enough, I got some devit but not as much. My second attempt was right first time using the 4th attempt firing schedule.

My biggest problem is patience. It seems as though I just have to learn from experience with this one. The trouble is I hate to throw any glass away, even if was a feebie. Any ideas as to what I can do with 3 failed snowflake experiments???
Logged
Pat from Canvey
Only a little bit odd
Forum Member
*******
Posts: 1222


Keep on blowing


« Reply #7 on: January 07, 2015, 03:20:47 AM »

You might try using devit spray and see if that helps, see http://www.warmglass.com/making_your_own.htm
Logged

Zeldazog
My name's Dawn, I'm an
Administrator
*******
Posts: 1048


I'm free, to do what I want...♪♪♪


« Reply #8 on: January 07, 2015, 04:17:53 AM »

Quote
http://When I said fuse I meant full fuse not tack fuse. As I mentioned I have tack fused float glass no problem & these are most certainly tacked, sorry I thought you could see this in the photo.
I thought it looked like it had tacked quite well, that was the confusing thing as you said it hadn't fused.  Smiley

Quote
http://All pieces fired 4 times. I was wondering if the devit somehow was holding the form so that it couldn't draw up properly.I wondered that.

Quote
http://The second firing was supposed to be a full fuse & this is where the devit appeared. The devit seemed to increase with each firing.
1510F = about 821C - I only get tack fuse at that.

Once devit has started, it will get worse each firing, as it's where the glass has crystalised, and the crystals will grow.

Quote
http://I have no idea what the glass was originally, it could have been window, greenhouse or double glazing, but I doubt if it was Pilkington K.

If it did come from a double glazing unit, why do you doubt it could be Pilkington K?  It's been used in DG units for years.  
« Last Edit: January 07, 2015, 04:19:24 AM by Zeldazog » Logged

Zeldazog
My name's Dawn, I'm an
Administrator
*******
Posts: 1048


I'm free, to do what I want...♪♪♪


« Reply #9 on: January 07, 2015, 04:29:18 AM »

My biggest problem is patience. It seems as though I just have to learn from experience with this one. The trouble is I hate to throw any glass away, even if was a feebie. Any ideas as to what I can do with 3 failed snowflake experiments???

Am much the same, hate to throw anything away.  However, after nine years of fusing, I really need to think about getting rid of something things!  Cheesy
Logged

Sharon the Cat
New Forum Member
*
Posts: 6


« Reply #10 on: January 07, 2015, 04:45:16 AM »

Quote
http://When I said fuse I meant full fuse not tack fuse. As I mentioned I have tack fused float glass no problem & these are most certainly tacked, sorry I thought you could see this in the photo.
I thought it looked like it had tacked quite well, that was the confusing thing as you said it hadn't fused.  Smiley

My abbreviations I use to myself Tack = tack fuse, Full = full fuse, Slump = slump. Why use 2 words where I know what one means? Wink

Quote
The second firing was supposed to be a full fuse & this is where the devit appeared. The devit seemed to increase with each firing.
1510F = about 821C - I only get tack fuse at that.

At what temperature do you normally get a Full Fuse with float?

Quote
http://I have no idea what the glass was originally, it could have been window, greenhouse or double glazing, but I doubt if it was Pilkington K.
If it did come from a double glazing unit, why do you doubt it could be Pilkington K?  It's been used in DG units for years.

I know the house concerned & if it came from double gazed units it would have to preceed those in place which have been there for over 20 years, & Pilington K I believe has been around for 21 years ish. Do you know if Pilkington K causes particular problems?

Perhaps I will be verrry brave & consign 3 first attempt experimental snowflakes to the bin. Cry
Logged
Zeldazog
My name's Dawn, I'm an
Administrator
*******
Posts: 1048


I'm free, to do what I want...♪♪♪


« Reply #11 on: January 07, 2015, 12:32:59 PM »

Depends if you consider a beautiful, sometimes, white, sometimes pink/green iridescent effect a problem :-) 

But the coated side will repel and the only way I've been able to get anything to full fuse to the coated side of K or E glass is to make sure it's covered completely and overlapped with the non-coated or plain float glass.

As said in an earlier post, I full fuse at 843 deg C and that gives a nice rounded edge with float or greenhouse glass.


I wonder if K glass was the first low emissivity glass?  Certainly the most well known I guess, but I have no idea if they were the first - a quick look on Pilkington site and it doesn't shout about being the first to develop it, so perhaps the glass was still coated with something?

Either way, I find the older the glass, the more issues I get with de-vit.  Someone gave me some old glass from their house, and that has gone cloudy, like devitrification without even going in the kiln!  Be interesting to see how that fires, although I am not looking forward to cutting it, expecting a few not going so well....

I personally like the fact that they're not fully fused, but I guess if that's not what you planned then you aren't going to be satisfied. 

Glass fusing certainly is a waiting game, not just because of the length of the firing cycles, but that "will it work this time, were the kiln fairies kind?" questioning doesn't go away!  Grin
Logged

Pauline
Forum Member
****
Posts: 271


happy happy happy


« Reply #12 on: January 07, 2015, 12:57:34 PM »

I'm not much of a fuser but have done some pieces with bottle glass and like this site
http://glasswithapast.com/recycled-glass-firing-schedules/

I haven't done any window glass but thought you might be interested
Logged
Sharon the Cat
New Forum Member
*
Posts: 6


« Reply #13 on: January 09, 2015, 05:36:03 AM »

Thank you Pauline.  I originally read up on higher temperatures for float glass on that site.
It is great source of information.
Logged
Decorative Glass Supplies
New Forum Member
*
Posts: 3


« Reply #14 on: February 13, 2015, 04:56:06 PM »

This is a common problem when using float glass from he local merchants. Unfortunatly the second and hird generation thermal efficency glass have a higher quality coating and is not always decrnable and as more 3mm glass is being used this will become an increasing problem You used to be able to detect using a magnetic light but since the composite of the coating has altered it is not so readily identified. Can I suggest that if it is 3mm that you are going to need that you look at horticultural float glass it is 3mm thick and can be identified with a slight oragnge peel finish. THis is npot coated and will be considerably less expensive or alternativly go for a sheet glass.
I hope this helps
Logged
Pages: [1]
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines Valid XHTML 1.0! Valid CSS!
Page created in 0.039 seconds with 19 queries.