Observation hole Plugged?
- This topic has 2 replies, 3 voices, and was last updated 8 years, 9 months ago by Anonymous.
- January 6, 2014 at 5:13 am #10068treadyParticipant
Hi everyone. Have already learned so much as a newbie combing over questions/answers on this forum. Thanks for all your comments!
I did my first bottle slump and my glass kiln seemed to take forever to get to the high temp of 1430. I have just purchased this used Olympic kiln and there was not a peep-hole plug with it. Do I need to plug the observation-hole (it’s cone-shaped) at the start of the firing or when I get to a certain temp to retain the heat to ramp faster? One bottle on a flat slump did pretty well, the other in a mold was dull and seemed to devit.
Also, I used the body firing setting and think from reading comments here that I should have used the top lid for firing?January 7, 2014 at 7:46 pm #13167TheMacdonaldParticipant
From everything I’ve read (much) and in my experience (somewhat limited) the hole does not need to be plugged. Only a minimal amount of heat will escape through the hole.
Likely you can order a plug from Olympic. I have two kilns, and don’t use the plugs in either.
TAMJanuary 9, 2014 at 2:55 am #13168AnonymousInactive
That’s correct. At fusing temperatures, air expands considerably resulting in a very thin atmosphere in the kiln. The lack of air means there isn’t anything to carry a lot of heat through the hole. The glass, on the other hand, is heated by radiant heat (line of site from the coils) so the absence of a lot of air isn’t an issue.
If you want to plug the hole, some scrap fiber blanket or paper will do the trick.
Helios Kiln Glass Studio
- You must be logged in to reply to this topic.