CraftWEB Hot Glass Talk  

Go Back   CraftWEB Hot Glass Talk > Hot Glass > General Hot Glass Discussion

Reply
 
Thread Tools Display Modes
  #1  
Old 07-11-2019, 01:01 PM
Sean Jones Sean Jones is offline
Registered User
 
Join Date: Jan 2016
Location: Staffordshire U.K.
Posts: 13
Sean Jones is on a distinguished road
Annealing schedule for crystalica

I bit the bullet and bought a tonne of crystalica but donít have an annealing schedule for overnight. They havenít published one and canít help as their technical bod is on holiday. The website has one for 1 inch thick but I need an overnight schedule for stemware.
Iíve built a 3 cubic foot box with 3Ē of fibre the runs great at 3kW through an SCR but would cool too slowly if I just turned it off.
Iíve got Glass Notes 4 and can use that but it seems mad to have to calculate it. Can anyone help.
Reply With Quote
  #2  
Old 07-11-2019, 01:36 PM
Eben Horton Eben Horton is offline
Registered User
 
Join Date: Apr 2002
Location: Wakefield, RI
Posts: 4,506
Eben Horton is on a distinguished road
You want my spruce pine schedule? It should be fine for your glass
__________________
<eben epoiese>
Reply With Quote
  #3  
Old 07-11-2019, 01:50 PM
Shawn Everette Shawn Everette is online now
Registered User
 
Join Date: Mar 2013
Location: Indianapolis, IN
Posts: 223
Shawn Everette is on a distinguished road
The PDF from Olympic has a 10 hour as follows:
510*c for 30 min
1.5 hours to 476*
3 hours to 416*
2 hours to 336*
3 Hours to 180*
off

My personal quick schedule when I was using it was:
510* for 3 hours
3 hours to 400*
6 hours to 150*
off
That handled most anything fairly thin and was quicker than most my kilns would allow.
Reply With Quote
  #4  
Old 07-11-2019, 04:28 PM
Eben Horton Eben Horton is offline
Registered User
 
Join Date: Apr 2002
Location: Wakefield, RI
Posts: 4,506
Eben Horton is on a distinguished road
Hereís mine.
4 hours @910
2 hours to 750
1 hour @ 750
6 hours to 100


This will anneal pretty much anything blown that isnít massively thick.
__________________
<eben epoiese>
Reply With Quote
  #5  
Old 07-11-2019, 05:07 PM
Pete VanderLaan's Avatar
Pete VanderLaan Pete VanderLaan is offline
The Old Gaffer
 
Join Date: Apr 2002
Location: Chocorua New Hampshire
Posts: 21,097
Pete VanderLaan is on a distinguished road
Spell it right:
Cristalica.

Otherwise, for stemware, put it away hot enough and it should not need more than 2 hours at the soak. Go to 700F for two hours. If the box is built well, turn it off.
__________________
Where are we going and why am I in this basket?
Reply With Quote
  #6  
Old 07-12-2019, 10:51 AM
Kenny Pieper Kenny Pieper is offline
Registered User
 
Join Date: Feb 2003
Location: Burnsville N.C.
Posts: 826
Kenny Pieper is on a distinguished road
Quote:
Originally Posted by Eben Horton View Post
Hereís mine.
4 hours @910
2 hours to 750
1 hour @ 750
6 hours to 100


This will anneal pretty much anything blown that isnít massively thick.
Whats your thinking for a hour hold at 750?
I don't think that would help anything
Reply With Quote
  #7  
Old 07-12-2019, 10:57 AM
Pete VanderLaan's Avatar
Pete VanderLaan Pete VanderLaan is offline
The Old Gaffer
 
Join Date: Apr 2002
Location: Chocorua New Hampshire
Posts: 21,097
Pete VanderLaan is on a distinguished road
I do a soak at strain point . It being defined as the point at which, going lower, no further annealing takes place. At that point you're just trying to avoid thermal shock.
__________________
Where are we going and why am I in this basket?
Reply With Quote
  #8  
Old 07-12-2019, 12:59 PM
Kenny Pieper Kenny Pieper is offline
Registered User
 
Join Date: Feb 2003
Location: Burnsville N.C.
Posts: 826
Kenny Pieper is on a distinguished road
Quote:
Originally Posted by Pete VanderLaan View Post
I do a soak at strain point . It being defined as the point at which, going lower, no further annealing takes place. At that point you're just trying to avoid thermal shock.
Right but the object is to get below the strain-point with no strain.
If you use a proper annealing temp the strain is released much faster than at the strain-point. In my understanding if the glass still has strain while approaching the strain-point something is wrong.
So if this is true a bit longer at the higher end of the annealing temperature will do much more than a hold at the strain-point.
Reply With Quote
  #9  
Old 07-12-2019, 02:59 PM
Eben Horton Eben Horton is offline
Registered User
 
Join Date: Apr 2002
Location: Wakefield, RI
Posts: 4,506
Eben Horton is on a distinguished road
Quote:
Originally Posted by Kenny Pieper View Post
Whats your thinking for a hour hold at 750?
I don't think that would help anything
Better safe than sorry. Thatís why I do it.

I know someone who anneals everything they make at 880 for 1 hour and 6 hours down to room temp. Thatís crazy IMHO
__________________
<eben epoiese>
Reply With Quote
  #10  
Old 07-12-2019, 06:11 PM
Sam Stang Sam Stang is offline
Registered User
 
Join Date: Feb 2018
Location: Augusta, Missouri
Posts: 17
Sam Stang is on a distinguished road
annealing

I got my annealing schedule from Gary Beecham so long ago that I can't remember when it was. 25 years or so. 3 hours to 750 from 920 (a bit lower for Spruce). Hold 1 hour at 750 and then down over 6 hours. I think my controller basically shuts off after the 750 hold though. I check it from time to time by making a 2" clear marble and I look at it under polarized light. It always shows no major stress so I guess I am doing it right. This is for relatively thin work but often with thick parts such as solid feet or handles. I occasionally run paperweights through this cycle but I would make them early in the day, thus giving them more time in the oven.
Reply With Quote
  #11  
Old 07-13-2019, 08:11 AM
Pete VanderLaan's Avatar
Pete VanderLaan Pete VanderLaan is offline
The Old Gaffer
 
Join Date: Apr 2002
Location: Chocorua New Hampshire
Posts: 21,097
Pete VanderLaan is on a distinguished road
Well, the clear witness weight is key to success. It doesn't lie.

It's again worth noting that annealing is a range and that the higher in the range you choose to anneal, the quicker the strain will be diminished to a safe level. It is not eliminated but is below the amount needed to survive well. I don't see the particular point of randomly choosing 750 as a soak point although I can see that soaking at the strain point is worthwhile. Kenny is correct in that the goal is to get to the strain point with tolerable strain and that would not happen if you just put it away at 700F. If you stayed at 700F long enough, it would eventually be annealed but that's one long soak.
Frank Wooley used to argue that a piece put away too cold would take up to 30 times longer to anneal than one put away at nearer to the upper annealing point in the range. Frank knew his stuff.I suppose one could conduct tests of that with clear witness pieces put away in every imaginable scenario.

With the cut forms I used to make, Not only did I put them away high in the range but I took the annealer up to 1100F for a short period. Those things were really hard to get to an even temperature prior to putting them away and it was the case that when doing the knife edged grinding they required that it was common to develop chaser cracks in the facets. If the discs were taken up to 1100F for 25 minutes, the cracks in the facets occurred far less frequently. I still have many of those blanks here but they need to be reannealed and taken above the upper annealing point or I'll likely lose them. I don't do much stuff like that anymore as the market really changed in 2008.
__________________
Where are we going and why am I in this basket?
Reply With Quote
  #12  
Old 07-15-2019, 08:26 PM
Jordan Kube Jordan Kube is offline
?
 
Join Date: Aug 2003
Location: Seattle, WA
Posts: 1,679
Jordan Kube is on a distinguished road
Quote:
Originally Posted by Sean Jones View Post
Iíve built a 3 cubic foot box with 3Ē of fibre the runs great at 3kW through an SCR but would cool too slowly if I just turned it off.
If it cools too slowly when you just turn it off, a controlled program won't get you there any faster. Unless I am missing something here.
__________________
WWUD? Think for yourself.
Reply With Quote
  #13  
Old 07-16-2019, 01:28 AM
Sean Jones Sean Jones is offline
Registered User
 
Join Date: Jan 2016
Location: Staffordshire U.K.
Posts: 13
Sean Jones is on a distinguished road
No, itís my typo. It comes down too quickly through the annealing range. Just like Dudley warns.
Reply With Quote
  #14  
Old 07-16-2019, 08:54 AM
Shawn Everette Shawn Everette is online now
Registered User
 
Join Date: Mar 2013
Location: Indianapolis, IN
Posts: 223
Shawn Everette is on a distinguished road
It's the fiber, you've got no thermal mass to absorb and hold heat. Even a kiln shelf in there might help.
Reply With Quote
  #15  
Old 07-16-2019, 09:01 AM
Pete VanderLaan's Avatar
Pete VanderLaan Pete VanderLaan is offline
The Old Gaffer
 
Join Date: Apr 2002
Location: Chocorua New Hampshire
Posts: 21,097
Pete VanderLaan is on a distinguished road
I have a softbrick floor and a kiln shelf
__________________
Where are we going and why am I in this basket?
Reply With Quote
  #16  
Old 07-16-2019, 10:42 AM
Eben Horton Eben Horton is offline
Registered User
 
Join Date: Apr 2002
Location: Wakefield, RI
Posts: 4,506
Eben Horton is on a distinguished road
Ideally I would want my annealer to drop by itself in 6 hours at a minimum .
__________________
<eben epoiese>

Last edited by Eben Horton; 07-16-2019 at 11:03 AM.
Reply With Quote
  #17  
Old 07-16-2019, 11:06 AM
Tom Fuhrman Tom Fuhrman is offline
Registered User
 
Join Date: Apr 2002
Location: hills of Tennessee
Posts: 1,395
Tom Fuhrman is on a distinguished road
I used to put a small section of steel railroad rail in my fiber annealer as a heat sink so I could just turn it off, that was before electronic controllers.
Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 07:53 AM.


All published comments within these message boards are the opinions of its contributor and does not represent
the opinion(s) of the owner(s) of this website. Please see the Terms of Use file for more details.

Books to Help Artists Avoid Online Scams: Top 10 Email Scams | Social Media Scams

Powered by vBulletin® Version 3.7.2
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
© CraftWEB.com. Opportunity Network. 2008. All Rights Reserved.