Rae Reich

Looks like a small well powered kiln. Depending on reduction schedule and firing speed restrictions of the wares you will fire likely 8 - 10 hours. If your wares are not particularly thick and you can go 400 - 600 degrees per hour with let’s say a 45 minute early reduction maybe gets you a bit faster down to 6 hours. This kiln looks like it can go to cone 10. One thing about small updraft kilns folks are prone to stalling them in very heavy reduction. The supervision of damper and gas is often something to get used to and too heavy a reduction will drop your speed a bunch. In my experience most folks tend to stall these kilns on their way to cone 10 so cone 6 reduction should be easier to hit.

Thanks, Rae!  That one is hand built with paper clay.  i made some with toilet paper (dissolved) and I think some nara porcelain.  I saw a video online about making the templates.  I think the top could be a little narrower but we are using it to make coffee and it works!

As someone who chased this particular dragon: no. I played with formulas and firing cycles, and you’re always left with at least some micro bubble clouding. 
Min’s right about the best way to make a glaze look clear over a dark clay body being an amber. If you want to play with marbling, you could try using a buff clay instead of the white. 

Congrats! 

Sounds like you figured out gas / damper and reduction indicators for you so your heating rates are acceptable. I have never had to strike or go into heavy reduction at the end but if you get the result you are looking for, then it is a technique successful for you. There are many schedules and techniques, I have never had to strike nor clean up the kiln at the end. My goal is always to get the uniform reduction I am seeking without a smokey mess and waste of fuel. Some test tile pics and midfire / later fire flames below. I use an O2 probe and built monitoring equipment, so a bit unfair, but a way to learn / teach basic reduction.
What works best for you and your glazes you will figure out - have fun firing!

Okay, so the first firing went pretty well.  The reduction worked well and it got to the correct temp...eventually.  I think I started at a lower temp in the morning than I used to with my old updraft kiln.  Therefore, it would take longer to get to Cone 10 by the end of the day.  So, I'll have to see how the next firing goes. 
Do I need to do a "Strike" at the end?   During a reduction firing in my updraft kiln, once the kiln got to 2350F,  I would close the flue almost completely for about 20 min. and this helped the reds and rutile glazes really mature and come out better.  I didn't do that with the downdraft kiln and the reds and rutiles came out really well.  Is this typical of a downdraft kiln?
Thanks for all the advice and help

If I understand your design correctly, the monkey's tail is where the bananas hang? If that is the case or even if not, but concern comes to any weight being on the tail. If there is weight on the tail, I believe it would break as the long thin tail. As @Kelly in AKsays you need a thicker tail part where it attaches to the monkey, tapering to the curve. The attachment to the monkey body could be done by a metal pin that would allow the takil to swing. Firing separately is the only method that seems to make sense.
 
best,
Pres

@Rae Reich Great suggestion, and thank you! I'll have to post a photo of the final design once complete. 

The only way around this is to add 2-4% red iron oxide to the clear base to tint it amber which will look more like the dark clay. Problem with this is it will also appear amber on your white lay and in some glazes the iron  produces specks in some base glazes. 
Part of the problem is from the calcium in the glaze, it’s in most, try avoid high calcium glazes. When I looked up the MC6Glazes liner it is quite high in calcium at 0.64 molar.

Because of the availability issues for Gerstley Borate and Custer Feldspar, I've been converting our studio glazes to use frits and G-200/Mahavir feldspars (with some tweaks for other ingredients to get the chemistry right). One thing that is quite noticeable is that many of the new versions will hard pan without the addition of Bentonite to the recipe. Some need as much as 3 or 4% Bentonite.  I'm doing line blends with different percentages of Bentonite in order to find the minimum amount that will prevent hard panning and keep everything in suspension for a reasonable amount of time. I'm just offering this as an observation for anyone who is heading down this path.
I'm 90% done with our recipes that need conversion. Later, after I get all the recipes completely done, I may experiment with other versions of recipes to get to the same results without needing Bentonite.

thank you babs.  that will be done with some of my sample pieces and with others dry.  my husband wanted me to make some new clay clock faces for his clocks, and i will do that with these to see how it all, works!!

If the pieces you are going to try on are absolutely dry, the u.g. may not adhere to it, may look ok after bisque, then bloat off when glaze fired.
This may not be the case with paperclay. I suggest spraying the pieces with water, then applying the u.g.
@neilestrick would know about this.

thank you,  Neil,  this makes a great deal of sense, and since i only glaze fired these two as a test, i will experiment further with your suggestions.  I am using the amaco underglazes and the coyote underglazes.  i have some nice thin paper clay test pieces that have not been bisque fired, and will do some experimenting with those.  perfect!!

I agree, the underglaze looks kinda thick. What brand of underglazes are you using? Most will give you a good solid color of you thin them down a little bit and apply 3-4 thin coats, brushing each coat in the opposite direction of the previous coat.
I find that clear glaze covers better when dipping if you apply the underglaze before bisque firing, so that the binders burn out in the bisque, leaving the surface more porous for the glaze application.

Paper clay would not be as strong imo as the paper burns out in the firing process, don't know if this makes it more brittle, someone will chime in 
https://community.ceramicartsdaily.org/topic/27135-working-with-paper-clay-questions/.

The clay will shrink so better make allowance when carving the grooves to attach to metal handle. Do you know the shrinkage rate of your clay body?
Can't advise on best way to fire, a lot hanging on that tail!!!!:-))

I love your monkey! The tail needs to go from thick to thin and be half as long. Long and skinny would be nice, but you’re asking far too much from the clay, if I’m understanding correctly. Especially if it’s expected to carry a load of bananas. 

The only thing that might make a difference is the slight increase in silica but my hunch is it won't be significant enough to make a difference, testing will tell.
Given there is no added standalone silica in the recipe to reduce it and get closer to an identical UMF you would need to reduce some of the silica while keeping the other oxides balanced. This is what the Target and Solve function did with it, reduced the silica by reducing the Nepheline Syenite then increased the Minspar (it has less silica than Nepheline Syenite) to rebalance the Sodium and Potassium then adjusted the Ball Clay to adjust the alumina and rebalance the silica. 
As well as how the glaze behaves in the bucket particle size and how well they melt comes into play also. 

Thank you to Madeleine and Callie Beller Diesal for your thoughtful replies, this is really helping me to understand the limits and benefits of the glaze softwares. I think I will take your advice and test both the direct 1:1 sub and the Glazy target and solve recipe! I'll do my best to report back what I find.
 
 

The target and solve function is supposed to get you a chemically identical recipe, one that will *theoretically* look the same. And that’s what’s happened here: all the ratios except for the calculated expansion in the first example are identical, and even those are only off by the faintest amount. 
However, target and solve doesn’t address bucket behaviour, which affects how a glaze applies to the pot, which in turn can affect the final look. Bucket behaviour is affected by things like changes in the total amount of clay, or in the amount of soluble materials. The total amount of clay in the target and solve recipe is a few percent higher than the original, and there’s a bit more soda ash. Not a lot in either case, but it could make this version a bit more prone to crawling than it already is, if applied thickly. 
The straight substitution recipe only has marginally more silica, and a slightly different expansion rate. But again, those changes are small, and any differences in the look of the glaze might depend on the clay body (crazing from expansion rate) and the firing cycle (gloss level from additional silica).
 
Best advice from here is to try them both and see which one you like better. Glaze software eliminates some physical testing, but  not all. 
 

Set the gas for the rate of climb you want, set the air for the degree of reduction, and set the damper so you have back pressure out both spy holes. One will have a lot of pressure, the other just a touch. Each time you adjust one of these the other two may need adjustment as well. There is such a thing as too much gas and air, and generally the damper will only need very small adjustments. Keep notes as you go.

Given this is a smooth white claybody that fires up to 1280C it could very well be the reclaimed clay just wasn't wedged properly. With pyroplastic claybodies if you don't get all the air bubbles out the clay what can happen during glaze firings is the air pockets expand and cause a bloat (sometimes called a bleb). Are you getting the problem more often with the recycled clay? 

This looks like one of those miracle clays but is really a cone 9/10 clay to get full verification. So it ought not bloat at cone 6/7. Can you post a picture or pictures of the defects you are seeing?

Hi Lindsay, welcome to the Forum!
Slowing your bisque - allowing more time to burn out impurities may help.
Choosing clay(s) that mature at your target temperature, I'll recommend that!
Are you firing your wares twice - bisque fire, then hotter glaze fire? 
...or are you single firing?
Either way, faster ramp up to target temp means less time to burn out impurities; your prior kiln allowed much more time.
Slowing your bisque fire, particularly around 1500-1800°F might help.
Adequate oxygen may also be important*.
If the clay hasn't changed, and you're firing to the same target temperature (verified by cones), the firing schedule is a likely culprit.
I'm seeing much less defects** since adding significant delays (on the ramp up and the ramp down) to my bisque schedule.
Bloating (digitalfire.com)
* Note the last sentence here: Kiln venting system (digitalfire.com)
**bloating in dark clays, particularly where the walls are smidge thicker;
"large particle defect" - random craters;
pinholes