Hulk

The color might matter.
The Axner site* indicates they've had good luck firing some of the colors to Cone 6.
Both Laguna and Axner otherwise indicate the Silky products are Cone 06. 
"Some Silky underglazes can be fired to cone 6 for similar results as shown below; we've had great results with SIL10, SIL44, SIL45, SIL47, SIL54, SIL55, SIL58, SIL60, SIL61, SIL67, SIL70, SIL71, SIL74, SIL76, SIL82, SIL84."'
Flamingo is SIL22?
Still, might try it with a clear glaze - test it with a clear glaze over the underglaze.
*Laguna and Axner merged some time ago. If I recall, Axner bought the Laguna company.

Hi MCB,
Is it the L&L "Vent-Sure" downdraft system that you're looking to install?
If so, good question on guidelines for routing the ductwork on or near flammables.
The L&L FAQs do have an entry on roof/ceiling penetrations:
"Do I need double wall duct when going through the roof?
You do not normally need double wall ducting when going through the roof since the pipe or duct does not reach high temperature. It is always advisable to check your local building codes for their requirements."
My guess would be to place somewhat between the duct and the flammable(s), a piece of tileboard perhaps.
Please check back for response from this section's Admin, who is very familiar with L&L equipment.
For the longer runs, smooth (rigid) pipe could be a better choice than flex pipe - less air resistance, easier to clean, and should last well.
 
The L&L documentation also indicates:
Length can be as great as 60 feet horizontal or vertical with up to four 90-degree bends.
Be sure to allow for adequate make up air - intake to equal what is being pulled from the space, hence an open window, vent, or somewhat to the outside.

For straight cuts, a tile saw might work.
We've used ours to cut bricks and pavers - goes through them like butter.
It's a wet process, so very little dust, however, for kiln shelving, thorough drying afterward.

Quick gelli plate and silkscreen process, with and without paper. 
Gelli plates don't contain gelatin but you can make your own gel plate using gelatin, don't know how well / long homemade gel plates last for. 
1 - gelli plate dusted with cornstarch (gelli plates come in different sizes, I'ld get one just big enough for what you want to screen) 
2 - silkscreen in place (can get custom made ones or stock ones, available from a few makers not just EZscreen, can also buy a blank screen and burn it yourself)
3 - Xiem rib used with thick underglaze. Either let it thicken up on it's own or thicken with Mayco silkscreen medium/powder. I tried the Mayco medium I think it's probably CMC, I prefer to just let it thicken on its own. Needs to be almost peanut butter thick.
If you use a gelli plate it needs to be applied to the pot (or vice versa) quickly while the underglaze is still wet. Either lift up the gelli plate and press it onto the pot or roll the pot across the gelli plate.
With paper instead of gelli-
1 - Rice paper (I buy from Sanbao but other places sell it too) rough side up, no cornstarch
2 - tape the screen down, same underglaze process 
Can also screen right onto pots if the screen isn't too large to be awkward. I find the paper is easier to apply to rounded forms.
  

 
 

We had wood and metal shops, laboratory Chemistry and Biology in seventh grade (near Pittsburgh, PA); art and music all through grade school, everywhere we went; sports options and PE class also everywhere. 
In grades eight through twelve, drafting; wood, metal, cooking, sewing and auto shops (I did a semester of wood, for access to the big saw, also one semester of auto, for access to the equipment to refurbish my cylinder heads); many music options, also theater and dance; an hour a week of "enrichment" course - I recall surveying and some heavy equipment driving; driver training course; several sports options; typing and office machines classes.
In the nearby public school districts (Central and Northern California), most of the shops have closed in the last forty years or so - also many dance, music, and theater studios have shuttered. There are more computer labs! I'd like to see more focused instruction in development (coding, e.g. Java, C++, Python) vs. just learning to run applications (e.g. Excel, Word, database, etc.).
Our Mother was an accomplished bowler (her average was well over 200 for many years), an internationally known specialist in embroidery, dabbled in oils and acrylics, sewed (from scratch) and repaired clothing, knitted and crocheted, and was a whiz in the kitchen. She learned to swim and play the guitar well after reaching her sixties.
Our Pop leveraged his background in heavy equipment repair and maintenance, welding, and machining (all in the logging trade) in his career as an Electrical Engineer. He designed and built several solutions in his work, also around the house and for his hobbies, e.g. he designed and built spearguns (for diving/fishing), fashioned belt buckles, designed and built nutcrackers...
Any road, we had hand work going on at home, all the time. We had access to tools, materials, workshop space, and the kitchen as well. We had our parent's support for just about anything we wanted to try. I started out with frying an egg at about five, was well into scratch cakes and pies by seven. My brother and I got into crepes later on. Mom cried.
We adjusted, cleaned, repaired and lubed/maintained our skateboards, bikes, motorbikes and automobiles. We took things apart and mostly put'm back together as well.
Pop used to bring things home for us to tinker with, e.g. his friend's broken Attitude Indicator (from a small plane). The friend was mad when Pop told him his seven year old son had disassembled the unit, found the fault, made the sketch, then re-assembled it.
All that to say that home and community are big influences.
I wasn't the one who picked up manual skills the fastest, that's for sure. I never did catch on to bowling, though try I did! I don't draw well, am fairly hopeless with sculpting, struggled with the violin for several years, was typically picked last for sports... I have some gifts - "perfect pitch" being one; stamina for the distance events, that's another; focus and persistence, that's helpful; a somewhat analytical approach, that's sometimes helpful too.
 

For straight cuts, a tile saw might work.
We've used ours to cut bricks and pavers - goes through them like butter.
It's a wet process, so very little dust, however, for kiln shelving, thorough drying afterward.

We had wood and metal shops, laboratory Chemistry and Biology in seventh grade (near Pittsburgh, PA); art and music all through grade school, everywhere we went; sports options and PE class also everywhere. 
In grades eight through twelve, drafting; wood, metal, cooking, sewing and auto shops (I did a semester of wood, for access to the big saw, also one semester of auto, for access to the equipment to refurbish my cylinder heads); many music options, also theater and dance; an hour a week of "enrichment" course - I recall surveying and some heavy equipment driving; driver training course; several sports options; typing and office machines classes.
In the nearby public school districts (Central and Northern California), most of the shops have closed in the last forty years or so - also many dance, music, and theater studios have shuttered. There are more computer labs! I'd like to see more focused instruction in development (coding, e.g. Java, C++, Python) vs. just learning to run applications (e.g. Excel, Word, database, etc.).
Our Mother was an accomplished bowler (her average was well over 200 for many years), an internationally known specialist in embroidery, dabbled in oils and acrylics, sewed (from scratch) and repaired clothing, knitted and crocheted, and was a whiz in the kitchen. She learned to swim and play the guitar well after reaching her sixties.
Our Pop leveraged his background in heavy equipment repair and maintenance, welding, and machining (all in the logging trade) in his career as an Electrical Engineer. He designed and built several solutions in his work, also around the house and for his hobbies, e.g. he designed and built spearguns (for diving/fishing), fashioned belt buckles, designed and built nutcrackers...
Any road, we had hand work going on at home, all the time. We had access to tools, materials, workshop space, and the kitchen as well. We had our parent's support for just about anything we wanted to try. I started out with frying an egg at about five, was well into scratch cakes and pies by seven. My brother and I got into crepes later on. Mom cried.
We adjusted, cleaned, repaired and lubed/maintained our skateboards, bikes, motorbikes and automobiles. We took things apart and mostly put'm back together as well.
Pop used to bring things home for us to tinker with, e.g. his friend's broken Attitude Indicator (from a small plane). The friend was mad when Pop told him his seven year old son had disassembled the unit, found the fault, made the sketch, then re-assembled it.
All that to say that home and community are big influences.
I wasn't the one who picked up manual skills the fastest, that's for sure. I never did catch on to bowling, though try I did! I don't draw well, am fairly hopeless with sculpting, struggled with the violin for several years, was typically picked last for sports... I have some gifts - "perfect pitch" being one; stamina for the distance events, that's another; focus and persistence, that's helpful; a somewhat analytical approach, that's sometimes helpful too.
 

We had wood and metal shops, laboratory Chemistry and Biology in seventh grade (near Pittsburgh, PA); art and music all through grade school, everywhere we went; sports options and PE class also everywhere. 
In grades eight through twelve, drafting; wood, metal, cooking, sewing and auto shops (I did a semester of wood, for access to the big saw, also one semester of auto, for access to the equipment to refurbish my cylinder heads); many music options, also theater and dance; an hour a week of "enrichment" course - I recall surveying and some heavy equipment driving; driver training course; several sports options; typing and office machines classes.
In the nearby public school districts (Central and Northern California), most of the shops have closed in the last forty years or so - also many dance, music, and theater studios have shuttered. There are more computer labs! I'd like to see more focused instruction in development (coding, e.g. Java, C++, Python) vs. just learning to run applications (e.g. Excel, Word, database, etc.).
Our Mother was an accomplished bowler (her average was well over 200 for many years), an internationally known specialist in embroidery, dabbled in oils and acrylics, sewed (from scratch) and repaired clothing, knitted and crocheted, and was a whiz in the kitchen. She learned to swim and play the guitar well after reaching her sixties.
Our Pop leveraged his background in heavy equipment repair and maintenance, welding, and machining (all in the logging trade) in his career as an Electrical Engineer. He designed and built several solutions in his work, also around the house and for his hobbies, e.g. he designed and built spearguns (for diving/fishing), fashioned belt buckles, designed and built nutcrackers...
Any road, we had hand work going on at home, all the time. We had access to tools, materials, workshop space, and the kitchen as well. We had our parent's support for just about anything we wanted to try. I started out with frying an egg at about five, was well into scratch cakes and pies by seven. My brother and I got into crepes later on. Mom cried.
We adjusted, cleaned, repaired and lubed/maintained our skateboards, bikes, motorbikes and automobiles. We took things apart and mostly put'm back together as well.
Pop used to bring things home for us to tinker with, e.g. his friend's broken Attitude Indicator (from a small plane). The friend was mad when Pop told him his seven year old son had disassembled the unit, found the fault, made the sketch, then re-assembled it.
All that to say that home and community are big influences.
I wasn't the one who picked up manual skills the fastest, that's for sure. I never did catch on to bowling, though try I did! I don't draw well, am fairly hopeless with sculpting, struggled with the violin for several years, was typically picked last for sports... I have some gifts - "perfect pitch" being one; stamina for the distance events, that's another; focus and persistence, that's helpful; a somewhat analytical approach, that's sometimes helpful too.
 

We had wood and metal shops, laboratory Chemistry and Biology in seventh grade (near Pittsburgh, PA); art and music all through grade school, everywhere we went; sports options and PE class also everywhere. 
In grades eight through twelve, drafting; wood, metal, cooking, sewing and auto shops (I did a semester of wood, for access to the big saw, also one semester of auto, for access to the equipment to refurbish my cylinder heads); many music options, also theater and dance; an hour a week of "enrichment" course - I recall surveying and some heavy equipment driving; driver training course; several sports options; typing and office machines classes.
In the nearby public school districts (Central and Northern California), most of the shops have closed in the last forty years or so - also many dance, music, and theater studios have shuttered. There are more computer labs! I'd like to see more focused instruction in development (coding, e.g. Java, C++, Python) vs. just learning to run applications (e.g. Excel, Word, database, etc.).
Our Mother was an accomplished bowler (her average was well over 200 for many years), an internationally known specialist in embroidery, dabbled in oils and acrylics, sewed (from scratch) and repaired clothing, knitted and crocheted, and was a whiz in the kitchen. She learned to swim and play the guitar well after reaching her sixties.
Our Pop leveraged his background in heavy equipment repair and maintenance, welding, and machining (all in the logging trade) in his career as an Electrical Engineer. He designed and built several solutions in his work, also around the house and for his hobbies, e.g. he designed and built spearguns (for diving/fishing), fashioned belt buckles, designed and built nutcrackers...
Any road, we had hand work going on at home, all the time. We had access to tools, materials, workshop space, and the kitchen as well. We had our parent's support for just about anything we wanted to try. I started out with frying an egg at about five, was well into scratch cakes and pies by seven. My brother and I got into crepes later on. Mom cried.
We adjusted, cleaned, repaired and lubed/maintained our skateboards, bikes, motorbikes and automobiles. We took things apart and mostly put'm back together as well.
Pop used to bring things home for us to tinker with, e.g. his friend's broken Attitude Indicator (from a small plane). The friend was mad when Pop told him his seven year old son had disassembled the unit, found the fault, made the sketch, then re-assembled it.
All that to say that home and community are big influences.
I wasn't the one who picked up manual skills the fastest, that's for sure. I never did catch on to bowling, though try I did! I don't draw well, am fairly hopeless with sculpting, struggled with the violin for several years, was typically picked last for sports... I have some gifts - "perfect pitch" being one; stamina for the distance events, that's another; focus and persistence, that's helpful; a somewhat analytical approach, that's sometimes helpful too.
 

@Hulk Thanks. I am going to try it on a white cone 6 oxidation - Lumos. I have made the Lumos before and the layering properties are amazing.

We had wood and metal shops, laboratory Chemistry and Biology in seventh grade (near Pittsburgh, PA); art and music all through grade school, everywhere we went; sports options and PE class also everywhere. 
In grades eight through twelve, drafting; wood, metal, cooking, sewing and auto shops (I did a semester of wood, for access to the big saw, also one semester of auto, for access to the equipment to refurbish my cylinder heads); many music options, also theater and dance; an hour a week of "enrichment" course - I recall surveying and some heavy equipment driving; driver training course; several sports options; typing and office machines classes.
In the nearby public school districts (Central and Northern California), most of the shops have closed in the last forty years or so - also many dance, music, and theater studios have shuttered. There are more computer labs! I'd like to see more focused instruction in development (coding, e.g. Java, C++, Python) vs. just learning to run applications (e.g. Excel, Word, database, etc.).
Our Mother was an accomplished bowler (her average was well over 200 for many years), an internationally known specialist in embroidery, dabbled in oils and acrylics, sewed (from scratch) and repaired clothing, knitted and crocheted, and was a whiz in the kitchen. She learned to swim and play the guitar well after reaching her sixties.
Our Pop leveraged his background in heavy equipment repair and maintenance, welding, and machining (all in the logging trade) in his career as an Electrical Engineer. He designed and built several solutions in his work, also around the house and for his hobbies, e.g. he designed and built spearguns (for diving/fishing), fashioned belt buckles, designed and built nutcrackers...
Any road, we had hand work going on at home, all the time. We had access to tools, materials, workshop space, and the kitchen as well. We had our parent's support for just about anything we wanted to try. I started out with frying an egg at about five, was well into scratch cakes and pies by seven. My brother and I got into crepes later on. Mom cried.
We adjusted, cleaned, repaired and lubed/maintained our skateboards, bikes, motorbikes and automobiles. We took things apart and mostly put'm back together as well.
Pop used to bring things home for us to tinker with, e.g. his friend's broken Attitude Indicator (from a small plane). The friend was mad when Pop told him his seven year old son had disassembled the unit, found the fault, made the sketch, then re-assembled it.
All that to say that home and community are big influences.
I wasn't the one who picked up manual skills the fastest, that's for sure. I never did catch on to bowling, though try I did! I don't draw well, am fairly hopeless with sculpting, struggled with the violin for several years, was typically picked last for sports... I have some gifts - "perfect pitch" being one; stamina for the distance events, that's another; focus and persistence, that's helpful; a somewhat analytical approach, that's sometimes helpful too.
 

This has been an interesting thread but I too feel like some comments can get ones back up a bit and I'm not too sure why.
Perhaps it's because many on this forum have been working in ceramics for decades and have put the time and energy into learning how to work with kilns and materials with the respect and knowledge they warrant. It becomes second nature, but it has taken years to acquire this knowlege / experience.
Perhaps there is a bit of unspoken animosity towards some social media type posts, on whichever platform that might be, that blow off this type of learning, usually by a blatant omission of info.
Perhaps there is also the opposite issue of fear mongering in regards to glaze chemistry folklore that is also seen / heard without substantiation. Fear of litigation has shut down more than one ceramics arts dept in schools.
I find that clearly defining what a question is within a post in conjunction with ascertaining a persons knowledge level / experience (hopefully) helps tailor suitable replies.
 
 

I went to a Composite high school, so yeah, there were all the home ec/welding/art/shop/automotive/beauty culture courses available. The school was set up as a precursor for trades or college or both. (Beauty culture is what they called it, but if you went through all the courses, you would up as a fully fledged hairdresser or esthetician). That was in the 90’s. 
Programs like this are still alive. My 14yo takes foods and fabrication as electives in jr high, and loves them. 
It’s hard for me to look at this question personally without viewing it through the lens of adhd, which, is highly heritable. I come from a long line of folks who were very smart, and didn’t hold still with any particular grace. Before computers, you either did things with your hands, or you went crazy. My Oma used to tell us that she had to give my dad stuff he could take apart and put back together, or he’d do it to something expensive like the TV. My mom’s side is all farmers and other flavours of highly capable people. So knitting, sewing, pouring candles, fixing things, projects involving creative reuse were going on constantly around me. I didn’t realize not everyone did that until I moved out and had roommates. 

In Southern California elementary school in the 50s we learned to write the alphabet by printing and then cursive (my youngest grandchild, 21,  cannot read or write in cursive  ). We learned to fold, cut, color, draw, paste (yum!) and glue (Elmers doesn’t taste the same anymore, either).  
My Mom was ‘crafty’ and my Dad was a mechanic/woodworker. They grew up during the Depression, so making well and making do were basic understandings.  I spent my free time making stuff, dolls and doll clothes and paper dolls with my best friend, and reading about making stuff. Sewing and cooking classes in 8th and 9th grade, wished I could take woodworking in High School, but that was for boys. I made a lot of my own clothes, also with a best friend (we wanted and needed to be original). Some Art teachers were inspiring and remembered fondly.
I’m jealous of folks who had ceramics in high school. It wasn’t until my second attempt at Junior College, age 22, that I finally found my clay calling   Hanging out with other clay people led naturally to construction, brick laying, booth building, photography, Volkswagen repairs, computer skills for brochures and flyers and accounts, and a sometimes economically perilous but fulfilling life of creativity.

Yes. I took 4 years of wood working, and 4 years of architectural drafting. Small engine repair, lathe, metallurgy, welding, and 2 years of mechanical drafting. 2 years of electrical wiring, a semester of electrical motor repair. I took Home Ec my senior year, but I already knew how to cook. Some farm classes, which were pretty much useless because I was a farm boy anyway. I excelled in chemistry, always had a curiosity about it. Enrolled in a local college to major in chemistry until I realized I would spend the rest of my life in a cubicle- so I dropped out.
Tom

@Denice, I also worked in a bank night duty, posting liability ledgers, trouble shooting branches that did not prove out, holiday decorating and signage using art skills. Did a 8' X 15' nativity scene for Christmas decoration, they hung it many years after I was gone in the lobby. So many different phases in life each seeming like an individual on their own. . . I am sure many have been the same.
 
best,
Pres

I thought my school had everything,  it was a very large school so they had more than enough kids to fill each program.   I was mostly in art and journalism but they had also so had cooking, sewing and secretarial program.   The art students could get help in the shop classes with tools that weren't in the art class  for their projects.   They had all kind of programs for the boys  drafting,  mechanics and shop class, they also had buses that would take the boys to a technical school for half days.    My mother in-law started telling me about her high school classes,  she lived in western Kansas.   They taught those children everything would would need to know to run a farm or ranch.  They also had a tough math,  English, and history curriculum  and broad sports programs for the boy and girls.  She died at the age of 98 two years ago she was a world traveler and worked at a bank with the first primitive computers.   Denice 

My middle school, H.S. years were in the late 50's early '60's and the only things girls could take were typing & home ec. Sewing was taught by the moms & art classes were fairly lame-I taught myself in terms of most hands-on art materials/processes. Where I lucked out was that my dad wanted a boy-no secret in our house-and got me instead. So, since I hated the rigid box for females, I pestered him until I was a full-fledged member of his Scout Troop & did everything the boys did, indoors & in the wild, and just as good. That earned me the privlege of being able to go down to the basement to my dad's shop where I got to do everything from manual & power equipment for wood/metal/plastic to working the Morse code for him (as a Ham radio operator) on his brass key pad. I didn't go to university art school until the '80s and by then things were much, much better--we women could & did the same things as the guys-no restrictions. So I learned a lot more in terms of dexterity , motor control etc, via ceramics, cold glass,wood, sculpture (lite welding), textiles, some manual typesetting, & pre-computer graphic arts...cut and paste was real different ha ha.   

My high school (graduated 1985) had a home economics room, complete with stovetops, ovens, and sewing machines. It had a well equipped wood shop, and a separate “industrial arts” lab. Two art rooms, one for fine arts and another for ceramics. It’s important to know the context of this was soon after a major oil boom in Alaska. 
A few years ago I was able to peruse the school district’s surplus warehouse. I was surprised by the number and variety  of stationary power tools that had been removed from schools.
What I see now in schools that’s analogous are robotics labs, 3-D printing, and CAD design spaces. Maker spaces. Definitely some hands on skills happening there, just not the kind I grew up with. Art rooms and ceramics labs still remain. Thankfully. 

I did wood shop and metal casting in Junior High (7-9th grades)now called middle school I think? sewing and typing was high school for sure.
In collage we had home economics and wood shop and auto repair (I took none of that )as I was 110% into ceramiucs /art major. 
I can from a family that made stuff and art was also in that mix so it was learned at home -surfboards from Balsa wood in the 50s and aluminum skateboards made with steel skates (before better wheels and wood tops).  Worked on Bicycles and mini bikes then go carts then cars. Was into wood work as a young boy and fiberglass as well. Pained my bike fram in 5th grade after stripping it down. School had programs then like shop and art as this was before Reagan killed the educational budjet for our state. Back when stuff with hands was common practice.
Now its all gone . Cal went from #1 in education (back in the day) to #37 in the Forbes Mag scale this past year. My mother taught Home economics in high school and collage for 35 years. I have little more than most in terms of this exposure.

Did your school have hands on subjects, shop, typing, home economics, sewing, anything where you used your hands?
I think this is a great question, and something that I have been considering for years since I have been a HS art teacher in a previous life! I remember my own US education where we were taught all sorts of fine motor skills from using scissors, and carving knives, up to band saws and table saws and drill presses in shop classes, how to use art materials in art classes with gluing, cutting, assembling with staples string and other things. I went to a college that had art education as a major, and there I learned about more hand tools and equipment in the studios, weaving, jewelry and metalcraft, ceramics, painting, drawing. Many of these I had learned much before,  but learned much more in the college studio classes and formal learning. Much of the foundation for all of this was learned from home, my parents taught us to use tools, my dad around the house and car, my mom taught me about sewing and mending clothes, we always cooked or baked together. Then their was the Boy Scouts and  i learned about camping in all seasons, making fires and cooking on them, water skiing, swimming and much more.
We look at the advances and benefits of computer operated machinery, robotic assembly and welding units, and lately 3D printers. We think Wow! so neat, so easily efficient, so safe! I remember my own US education where we were taught all sorts of fine motor skills from using scissors, and carving knives, up to band saws and table saws and drill presses in shop classes, how to use art materials in art classes with gluing, cutting, assembling with staples string and other things.  Yet what are the consequences? @Kelly in AK posted his notice of the decline of students in their manual dexterity at being unable to do simple tasks like fold paper, use scissors and such. Sad to say, but I believe him, and hate to prognosticate where this may lead to in our society. Will folks loose their ability to use their hands for simple tasks like cutting out a snowflake, beyond just forgetting how to fold the paper for the snowflake? Throw in your thoughts folks and lets have fun the future is here!
So should we expand this question to ask where you learned physical dexterity skills and how?
Thanks for your question oldlady!
best,
Pres

For straight cuts, a tile saw might work.
We've used ours to cut bricks and pavers - goes through them like butter.
It's a wet process, so very little dust, however, for kiln shelving, thorough drying afterward.

I have always wanted to experiment with fritware and only having access to a small kiln that struggles to reach top temperatures I thought it may be worth trying out.
 
First some vague calculations to see if it makes sense.
I think electricity prices in the UK are pretty extortionate right now at £0.30-£0.60p a kwh. My kiln takes at least an extra 2.5h to get from 1100c to 1260c+ and at 3kwh * 0.40p * 2.5h = £3 extra a firing if I am getting a "good price" on electricity
Clay can cost anywhere from £0.40 per kg to £1.30 per kg and I am assuming around 25% of that is water. A powdered stoneware costs about £1.50 a kg so lets call it £1 a kg for a ballpark figure buying 100-250kg a go.
I could fit maybe 10 mugs in my kiln at say 450g a mug so total clay cost would be £4.50, with the extra £3 a firing that means I can 'break even' with a fritware body costing £1.66 a kg. A Larger kiln should work out more efficient on energy I think so less extra cost.
 
I have two ball clays and a kaolin kicking around so after reading kaolin can take up to 30% frit I decided to start with the ball clays. Hyplas 71 and Hymod AT at £0.90 per kg (25kg bags). Not sure I am in the power or fiberglass industry but they sell it at pottery suppliers

 
Next are the frits that run from £6-10 a kg (25kg bags). I think they are pretty expensive in the UK.
I went with an Alkaline Frit (similar to 3110 but cheaper) and Ferro Frit 3124, 3134 and 3195 for the glaze and to try in the body.
 
At 5% frit to ball clay it will cost £1.16-1.31 per kg.
At 10% frit to ball clay it will cost £1.41-1.73 per kg.
At 20% frit to ball clay it will cost £1.93-2.56 per kg.
 
Looking at that I thought it was definitely worth trying as I could possibly get it under £1.66 a kg. I guess I need to factor in my time making the clay into the cost but if I am planning on casting I feel it would be similar anyway to making a stoneware slip.
I tested each ball clay with 5, 10, 13, 16 and 20% frit in the order Alkaline, 3124, 3134 and 3195. The last 4 tests have a 50/50 mix ball clay to kaolin and 20% of each frit. Fired to cone 03 and then boiled for 5 hours to get the absorption values.
The results actually came out better than I expected with Hymod ball clay and 10% alkaline frit getting to 0.5% absorption at £1.41 per kg I think B0011 I must have messed up as the data doesn't fit.
 
 
Colours are sort of accurate in this photo, not a very good camera on my phone.

 
Now I am experimenting with adding different Calcium Magnesium and Lithium fluxes to see what happens.
Reading that I could have issues with drying times using pure ball clay. It's interesting that the Hyplas has larger particles than Hymod but it is sold as the more plastic, maybe there's something I am missing.
Never did any working out for how much more the glaze costs so maybe that will make things look worse but hopefully it is such a small % total it doesn't make much difference.

How I'm reading his comments are the recipe won't work without the manganese and copper as they are necessary to flux the glaze. He did state the glaze without the manganese and copper won't work as those two oxides are necessary to flux it. It looks like he's taken a typical Metallic Glaze with high manganese and swapped the redart for custer, kaolin and a bit of talc.
I don't know what Glazy's policy is on posting recipes that aren't suitable for functional ware surfaces with or without a caveat stating so, perhaps that is something to bring up with Derek Au. We do make a point of stating if a glaze isn't suitable for pots coming in contact with food surfaces on this forum and to fire glazes or claybodies, slips and engobes containing manganese in a very well ventilated area.  No, I don't think you are an "old codger" telling people you shouldn't use such glazes inappropriately. 

The glass item appears to be a reed switch. You would replace with a reed of the same or higher operating voltage and amperage while it needs to physically be the same size. The reed appears to be single throw, single pole - normally open. Goodwin definitely best choice.