Jump to content
Sign in to follow this  
Mountain Meg

Reliable Cone 6 Temmoku Glaze Recipe Oxidation

Recommended Posts

I am firing one single cup. The worst yunomi I have made in a while and kept. So plain and ugly. But it will be a good glaze testing cup. Poured the inside with one pour and triple dipped the outside for thickness. I am firing to 2165 with a 50 minute hold, should put me to cone 6 6.5  then I am dropping 9999 til 1742 and holding for an hour. It will be interesting to see.

 

I didn't have time to modify my glaze I keep all my test batches in small 100 containers. My garage literally has over 100+ small containers of test glazes lol. I went and found my modified V's gold and I am firing it now. I will post results tomorrow afternoon. 

 

I hope yours comes out good. I would love to have a beautiful tenmoku.

 

I think Mountain Meg is laughing at us, she asked for a recipe and we are trying to find one for everyone! haha. lots of great information in this thread though.

Share this post


Link to post
Share on other sites

 

I sometimes realize too late that I give responses that assume other people can hear everything that goes on in my head, and not everything made it onto the page that should have. I thought this might have been one of those instances.

 

Ditto.

 

 

You mean you don't make up peoples responses in their head in your head? I know your thoughts  B)

Share this post


Link to post
Share on other sites

thank you joseph.  your answer to mountain meg sent me to a video i have been looking for.  a side benefit!  it is the one of mylar slip applicators.  thanks again.

Share this post


Link to post
Share on other sites

Very timely thread.  I too have been playing with temmoku glazes at cone 6 oxidation.  I just took this pot out of the kiln over the weekend.  It is a layer of modified (RIO up to 14%) Rick Malmgren's Temmoku, from CM 10/2000, with a rim dip and spatter of a second glaze on top.  The second glaze contains:  OM4, custer, silica, whiting and GB, with RIO, rutile and a tiny CuCo3.  Fired to cone 6 in an electric kiln and slow cooled from 1925-1400'F @ 100'/hr.

 

It breaks more of an amber honey color not as red as you might want, but the yellow crystals are amazing.  Usually I see magnesium added for the teadust look, but I added none.  It may be getting enough from the gerstley and OM4 I guess.  I've done a quite a bif of testing and am a fan of slow cooling many glazes.  The one picture is a digital microscope capture of the most concentrated yellow crystal area at about 150X. 

 

This may be nothing like you're looking for, but I thought I'd share.

 

 

post-64856-0-64353800-1452189603_thumb.jpg

post-64856-0-52287900-1452189611_thumb.jpg

post-64856-0-87442600-1452190357_thumb.jpg

post-64856-0-64353800-1452189603_thumb.jpg

post-64856-0-52287900-1452189611_thumb.jpg

post-64856-0-87442600-1452190357_thumb.jpg

Share this post


Link to post
Share on other sites

So here are the results of my reading that thread on iron that Joel posted.

 

I fired to cone 5 with a 50 minute hold, and then dropped naturally to 1742 then held for an hour. The cones bent to a perfect cone 6. 

 

IMG_20160107_183155453_zps9snuolrs.jpg

 

 

 

 

IMG_20160107_183207922_zps0rol45o9.jpg

 

 

IMG_20160107_183214332_zpsu6vv3prc.jpg

 

IMG_20160107_183224820_zpsa2qgqwfn.jpg

 

 

IMG_20160107_183234426_zpsjp5i72em.jpg

 

 

It is an interesting glaze with all the crystals, but it isn't the colors I want. I want the crystals to be reddish orange and I want the glaze to be a dark black not a brown amber. 

 

Either way it is interesting how the 1 hour hold at 1742 brough out billions of crystals from the iron so perfectly without doing anything to the surface of the glaze as far as matting goes. 

 

The cup itself is very pretty. If your into the whole glaze drip/crystal thing. This would a great glaze for the inside of a large shallow bowl that fruit and stuff goes in. very beautiful to look at and you don't have to worry about the runs. 

Share this post


Link to post
Share on other sites

Joseph:

 

Looks like test formula 2 produced some really interesting results. I am firing it again tonight along with some crystalline test pieces. So it will have a 3 hr soak at 1940F... might be a little too short of a hold. :blink:  Adjusted the FE from 11 to 13, the rest of the minor changes I left. Got pretty close, but had an interesting gold band between the black, and then plum red. My old cheap camera would not pick it up very good. Test tile 3 was rather bizarre, had 1/4" gold crystals, but vandium is a known seeding agent for crystals. May have to shorten the slow cool ramp. I am firing on porcelain though; only clay I have besides B-mix stoneware. Will try to post pictures tomorrow night. 

 

Cheap way to practice using your new sprayer: Mix plain ole cheap silica with 1/2% iron with water: practice spraying on cardboard. The iron will allow you to see your spray pattern. Very cheap way to practice and get use to something new. After you get done spraying, pop the cap off the glaze holder and submerge the whole thing in a 5 gal bucket of water and purge. Makes cleaning easier.

 

Nerd

Share this post


Link to post
Share on other sites

My next plan is to refire a tenmoku to cone 04 to see if the color changes. If it works I could always refire pots in the next bisque with a slight adjustment for quartz inversion.

 

Looking forward to seeing your tiles.

 

I need to figure out what iron produces redder crystals or orange ones like in reduction. I am not a fan of the yellow ones as much.

Share this post


Link to post
Share on other sites

 

 

I need to figure out what iron produces redder crystals or orange ones like in reduction. I am not a fan of the yellow ones as much.

 

 

 maybe your customers do.

 

 

This is a point. I mean the glaze isn't ugly by any means. It just isn't exactly what I am looking for, but I plan on using it for sure. I have to test my other glazes with this firing schedule to see if they go all haywire as well. I plan on doing that probably tomorrow.

 

Also gonna mix up 10-15 different batches of the above glaze with addition of some EPK for alumina to stop the runs as well as some bone ash.

Share this post


Link to post
Share on other sites

Joseph:

 

The thought occurred to me today while cleaning my slab roller: why does this recipe has 6% lithium at cone 6? I fire crystalline to cone 6 with 3-4% lithium which results in an extremely fluid glaze by design. I think the color is right where you want it and you are just fighting fluidity issues. Have you tried this recipe with 3-4% lithium- I do not see that affecting the color.  Just a thought..

 

Nerd

Share this post


Link to post
Share on other sites

So I haven't had a chance to test the new glazes yet. I am running a bisque firing tonight on some test tiles. However I did toss that pot back into a custom bisque schedule that slows down during quartz inversion. I am refiring the cup to cone 04 to see if the glaze changes color like the article lead to. It will be interesting to see. I will post results. 

Share this post


Link to post
Share on other sites

Just as a datapoint, I'll post a picture of an iron red that I've recently started using.  As Neil mentioned, there is some phosphorus and some lithium in this glaze.  I wonder if you could use an overdip of this glaze on a black temmoku-like glaze to get red crystals.   This is a Cone 8 glaze, but I think there is a Cone 6 version.  This is with normal cooling-- I believe that more spectacular crystals could be developed by slow-cooling.

post-65900-0-10081800-1452703320_thumb.jpg

post-65900-0-48163600-1452703320_thumb.jpg

post-65900-0-10081800-1452703320_thumb.jpg

post-65900-0-48163600-1452703320_thumb.jpg

Share this post


Link to post
Share on other sites

@Ray That is pretty interesting Ray. Nice Pipe. The colors are very iron rusty. The thing I have found with layering the tenmoku's is that they just turn out to be very oilspotty look instead of the black tenmoku look.

 

----

 

So as an update. I refired the cup above to a cone 04 bisque to test color changes as per that article. The entire cup turned a rusty pink red color. The crystals faded away except at the thick parts and turned a puke green yellow color instead of a golden flake color. So that was a no go on turning a black red. It turned to pink red, and went from glossy to matte with a really bad surface. See attached.

 

I have mixed 5 new versions of the tenmoku posted above. I fired them with a regular cooling schedule and they all pretty much looked like the first tile I posted. With the exception of the ones with Bone Ash. They had some faint redding in them. However they seemed to run more and become even more transparent at the top. If they turn out to be a really nice red black then  I will modify the lithium and add small amounts of EPK to see if I can stop the running so that the entire glaze wont be amber at the top.

 

For further testing I am firing those same glazes again in a firing that holds at 1742F for an hour again to see if the results are more interesting. I presume they really will be. The only issue is I am using a different clay body because I didn't have any test tiles from the other body bisqued. They are all drying. So it will be slightly darker body, but still should show the results good enough if anything it will be a darker tenmoku instead of an amber one.

 

I also fired all my current glazes with the same schedule, because of the tenmoku came out so awesome looking I figured some of my other glazes might look better with that schedule. I fire a lot of glazes with iron in them at small %'s. 

 

I will post results of the test tiles tomorrow evening when the kiln is done cooling. Times like these I love my little 2.7CUFT L&L. 

post-63346-0-72506900-1452735334_thumb.jpg

post-63346-0-02517600-1452735335_thumb.jpg

post-63346-0-72506900-1452735334_thumb.jpg

post-63346-0-02517600-1452735335_thumb.jpg

Share this post


Link to post
Share on other sites

@Ray That is pretty interesting Ray. Nice Pipe. The colors are very iron rusty. The thing I have found with layering the tenmoku's is that they just turn out to be very oilspotty look instead of the black tenmoku look.

 

---

 

Joseph, if you'd like to look into it, the original recipe was Bailey's Red from one of John Britt's books, modified for Cone 8.  I'm sorry, but I can't remember if it was modified from a 10 or a 6 version.  I seem to remember that there was a Bailey's Red in both books, but I could be wrong.  But anyway, if you look at what's going on with that glaze, it may help shift your temmoku toward more red crystallization.

 

Here's the modified for Cone 8 recipe:

 

37 Custer spar

20 silica

  7 ball clay

15 talc

15 Bone ash

  6 lithium carbonate

 

+12 red iron oxide

post-65900-0-92795900-1452750801_thumb.jpg

post-65900-0-92795900-1452750801_thumb.jpg

Share this post


Link to post
Share on other sites

Joseph, I was back at my parents house yesterday looking at an iron glaze over a cobalt carbonate slip, VERY dark black compared to the normal brown glaze. Didn't get a snap but I think try a 2-4% cobalt slip under the glaze for black. It was cone9 though. Now I read a bit it looks like you want a red and black is ok.

 

That glaze is real nice, I like it. Besides the messed up surface. I have had that happen the few times I have done a decal firing. Especially with high iron glazes. 

 

I bet to stop it running you could swap out 5% frit for a feldspar.

Share this post


Link to post
Share on other sites

@Ray. It looks like the thick pooled surfaces places on that pot almost resemble a tenmoku really. I can't tell from the picture is the surface glossy or matte? It looks almost satin. Also what grade of Iron Oxide are you using? The brownish red color makes me think a natural RIO? 

 

@HBP. I haven't tried making any slips with oxides or stains yet. Maybe later. Thanks for the good idea though. I also have a version that doesn't run much at all. I added 3% EPK and lowered the lithium 3%. Nothing really changed in the firing without a hold at 1742F. It will be interesting so see if it changes greatly compared to the other one when I pull it out this afternoon. I will post results.

 

I also tried a few variations of things that kinda came to me last night while I was laying in bed. I put some iron stain under the tenmoku to see if it would darken the places where the glaze goes semi transparent. I don't know if it will work or not but if it does it is a very simple solution for me. 

Share this post


Link to post
Share on other sites

http://community.ceramicartsdaily.org/tags/gallery/Iron%2Bred%2Bin%2BOxication/

 

This was a test for iron red. I used some lithium wash for the dots. The edges were a a little thinner and black held at 1900 on the cool down.

 

Marcia

Share this post


Link to post
Share on other sites

Joseph, the glaze is pretty glossy, but is not a perfect limpid gloss-- there's a tiny bit of tooth to it, probably caused by healing pinholes.  It's possible a hold at top heat could make it flawlessly glossy, though for a fact I like a little texture to my glazes.  A hold during cooling would probably result in a red micro-crystalline surface, which I assume you don't want. I think it is a pure oxide, though in high iron glazes I've never noticed a lot of difference in the effects of different iron sources.  12 percent of any iron will probably lead to a deeply saturated color.

 

I'll include a close-up.  This really isn't very much like a temmoku, but it might help you move your temmoku toward a red break, if you work a bit of this into your temmoku glazes.  You can see some oil-spotting on this glaze, though the spots are very small.

 

I should probably add that this is on porcelain, which may make a difference.

post-65900-0-71064500-1452789367_thumb.jpg

post-65900-0-71064500-1452789367_thumb.jpg

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.