Jump to content
Sign in to follow this  
Achilles

Glaze Firing Cone Packs — Can They Be Bisqued First?

Recommended Posts

I understand from reading other threads on this topic that I can make a cone pack by putting cones in some clay wadding; however, they will explode if they heat up too quickly. Since I glaze using a fast firing schedule, I am concerned about this risk, and thought it might be safer to first include the cone packs in my bisque firing, since the bisque uses a long, slow schedule. 

 

So my question is: if I put a bunch of Cone 6 cone packs (i.e., cone 6 cones in clay wadding) in with a cone 04 bisque, can I then use them in later glaze firings? Or are the cones less effective if they go through a preliminary firing, even if they don't reach Cone 6 temperature?

Share this post


Link to post
Share on other sites

I put green cones in a hot raku kiln all the time, never been an issue. The wadding's blown up on me, but never a cone. That said, gas does different things than electric. Electric seems to pull more moisture out faster. That may affect things.

 

I will say that bisquing your cones will change how they measure heat work. Cone 6 won't necessarily be cone 6, since some of the work is already done.

Share this post


Link to post
Share on other sites

You can just use scrap clay, don’t need to use wadding, poke a bunch of holes in the cone packs with a pencil tip after you’ve pressed the cones in. Make up a bunch of them and let them dry out so they are ready to go when you need them.  Doesn’t matter if the clay cracks a bit, I've never blown up a cone pack Just be sure to have the angle they stand up at correct, cone should be at 8 degrees which is simple enough to do by holding the cone so the bottom sits flat on the tabletop then keep that same angle when pushing it into the clay.

 

Also, it’s helpful to use 3 cones in a pack, a sentry cone (^5) first, target cone (6) in the middle and a guard cone (7) last. This way if you are watching the cones towards the end of the firing the 5 will give you warning you are getting close and the 7 lets you know if you have over fired. 

 

Once you get used to how your kiln fires you might want to then cut back to just using a single cone in the pack.

 

 

+1 for what Tyler said about not bisque firing them first.

Pres and douglas like this

Share this post


Link to post
Share on other sites

What Min and Ty said. I make up 1/2 a dozen-dozen in advance. I use raku clay because I don't want to waste porcelain. I have raku clay around or stoneware if you have it.  Poke a bunch of holes with a pin tool and let them dry out well. Three cones as Min says. 

Marcia

Pres likes this

Share this post


Link to post
Share on other sites

I always use clay wadding to support my cones, and I have never had one blow up yet. I (mostly) let the clay dry before placing in the kiln. Made by wrapping a small coil of (vaguely grogged) clay around the cone base, and squishing. Set them up in a row. Like ducks.

 

cone

Share this post


Link to post
Share on other sites

When you buy your cone packs immediately put them into clay pats. Then just let them dry like Min said. Once they sit out for a few days the clay pats will be plenty dry to fire. 

 

I have a shelf of cone packs sitting in pats. I just pick 3 off every time I modify my firing schedule. It's nice to have them all ready. 

Share this post


Link to post
Share on other sites

I use sawdust mixed in scrap clay, set in my cones then let them dry for at least 2 days before placing them in the kiln.

 

I've been thinking about making some permanent cone holders from high temp fire brick just in case I run out of cone packs. Has anyone tried this?

Share this post


Link to post
Share on other sites

Just make your cones days in advance -you can add sawdust or vermiculite to scrap clay-I keep my cones on a heater so they are dry always .Do not bisque fire your cones as that can change them.Once the clay dry you can fire as fast as you want-do what Min says and poke the holes in the pads.

RonSa likes this

Share this post


Link to post
Share on other sites

I do make them in advance, I'm just thinking ahead in case I forget to make them ahead or I run out and didn't notice :unsure:

Edited by RonSa

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×