RobS

Here's the results of my various tests with this slip clay I found.  I tested:
Test tiles are Standard 630 fired hot cone 6 oxidation.
various levels of RIO from 2% to 20%
frits 3124 and 3195 from 5-20%
spodumene, whiting, gerstley, rutile 10-20%
copper carb, cobalt oxide and carb, chrome oxide, yellow ochre
Most of the tiles were either chocolate brown or mahogany brown, depending on which base slip I used.  There were a few that are interesting.  The ones with whiting turned out a silky butterscotch color, the one with whiting and cobalt(242 in the pic) breaks glossy black on the edges and is an interesting shade of grayish/tan/brown where thick and the one with speckles is gerstley borate at 10%.  Also, there are a couple that are quite close and could be a very nice gloss black if I tweaked the cobalt/iron levels a bit I think.
I haven't done any durability testing as of yet.  I think I may try some triaxial blends or currie grids with whiting, cobalt, gerstley to see if there are more interesting things.
 

One more pic of the GB tile as I ran over my 1MB limit.

One more pic of the GB tile as I ran over my 1MB limit.

Here's the results of my various tests with this slip clay I found.  I tested:
Test tiles are Standard 630 fired hot cone 6 oxidation.
various levels of RIO from 2% to 20%
frits 3124 and 3195 from 5-20%
spodumene, whiting, gerstley, rutile 10-20%
copper carb, cobalt oxide and carb, chrome oxide, yellow ochre
Most of the tiles were either chocolate brown or mahogany brown, depending on which base slip I used.  There were a few that are interesting.  The ones with whiting turned out a silky butterscotch color, the one with whiting and cobalt(242 in the pic) breaks glossy black on the edges and is an interesting shade of grayish/tan/brown where thick and the one with speckles is gerstley borate at 10%.  Also, there are a couple that are quite close and could be a very nice gloss black if I tweaked the cobalt/iron levels a bit I think.
I haven't done any durability testing as of yet.  I think I may try some triaxial blends or currie grids with whiting, cobalt, gerstley to see if there are more interesting things.
 

Here's the results of my various tests with this slip clay I found.  I tested:
Test tiles are Standard 630 fired hot cone 6 oxidation.
various levels of RIO from 2% to 20%
frits 3124 and 3195 from 5-20%
spodumene, whiting, gerstley, rutile 10-20%
copper carb, cobalt oxide and carb, chrome oxide, yellow ochre
Most of the tiles were either chocolate brown or mahogany brown, depending on which base slip I used.  There were a few that are interesting.  The ones with whiting turned out a silky butterscotch color, the one with whiting and cobalt(242 in the pic) breaks glossy black on the edges and is an interesting shade of grayish/tan/brown where thick and the one with speckles is gerstley borate at 10%.  Also, there are a couple that are quite close and could be a very nice gloss black if I tweaked the cobalt/iron levels a bit I think.
I haven't done any durability testing as of yet.  I think I may try some triaxial blends or currie grids with whiting, cobalt, gerstley to see if there are more interesting things.
 

One more pic of the GB tile as I ran over my 1MB limit.

Tom,
I appreciate the insights into my material.  I would like to at least do my due diligence with respect to the uses of this slip.  I would like to continue testing and working with this material in the vein of maybe finding an interesting glaze result.  I've seen Albany slip used to make some beautiful glazes like a nice black and a few different oil spot type glazes.  I know most of that work was done at cone 10+ and mostly reduction, but if I could come up with a glaze or two using this slip as the main ingredient at cone 6, that would be nice.  I think as a body, this material would need too much tweaking but as a glaze ingredient I most definitely would love any and all advice on fixing it or glaze addition ideas.
I have about 30 tests in the kiln right now and will post  pictures of the results tomorrow. 
Rob
 

Tom,
I appreciate the insights into my material.  I would like to at least do my due diligence with respect to the uses of this slip.  I would like to continue testing and working with this material in the vein of maybe finding an interesting glaze result.  I've seen Albany slip used to make some beautiful glazes like a nice black and a few different oil spot type glazes.  I know most of that work was done at cone 10+ and mostly reduction, but if I could come up with a glaze or two using this slip as the main ingredient at cone 6, that would be nice.  I think as a body, this material would need too much tweaking but as a glaze ingredient I most definitely would love any and all advice on fixing it or glaze addition ideas.
I have about 30 tests in the kiln right now and will post  pictures of the results tomorrow. 
Rob
 

Tom,
I appreciate the insights into my material.  I would like to at least do my due diligence with respect to the uses of this slip.  I would like to continue testing and working with this material in the vein of maybe finding an interesting glaze result.  I've seen Albany slip used to make some beautiful glazes like a nice black and a few different oil spot type glazes.  I know most of that work was done at cone 10+ and mostly reduction, but if I could come up with a glaze or two using this slip as the main ingredient at cone 6, that would be nice.  I think as a body, this material would need too much tweaking but as a glaze ingredient I most definitely would love any and all advice on fixing it or glaze addition ideas.
I have about 30 tests in the kiln right now and will post  pictures of the results tomorrow. 
Rob
 

Greetings,
I have a very interesting material on my hands.  Quick background.  My uncle has lived in this area for most of his 70+ years and is familiar with the local waterways and he had been telling me about a layer of clay in the Chemung riverbank for a long time.   Last summer we took a canoe and a couple of 5 gallon buckets and set out to find the clay.  Downstream a bit, we found the clay.  Two adjacent layers, a yellowish/brown and a gray.  Upon shoveling them into the buckets, my first thoughts were this stuff is too sandy for anything.  The gray was more wet and did feel a tad thixotropic which was interesting.  Fast forward to December when I thought I'd at least slake down some of the clay, dry it out and do some testing.
Slaked and turned into a slurry it stays suspended.  Upon sieving, it is 100% finer than a paper coffee filter (15 microns I'm guessing).  It passed through a reusable gold coffee filter (20 micron ?) as a thick slurry as it were plain water.  I had to add a little extra water to get it to go through the paper filter but it dripped through after a while.  There's no extraneous matter in this stuff.  I dipped a test tile in the slurry.  The slurry dewaters as it were sand.  Placed on plaster the wet slurry is able to be removed and worked within minutes.  Almost no plasticity.   I made test bars and a drying test disc.
I did not measure the wet to dry shrinkage of the test bars, but wet to cone 04 shrinkage is 1%.  At cone 04 the clay is super light and porous and probably absorbs twice its weight in water.  I didn't quantify it.  I put the test tiles in a cone 6 oxidation glaze firing and added a test bar and as an afterthought, a waster slab.  I was surprised when I opened the kiln and saw the tiles.  The yellow/brown clay is the one that fires a touch more chestnut reddish color.  This was a hot cone 6 firing with cone 7 ending at about 10 o'clock.  The melted lump in front of the test tile was a test bar marked at 30 mm for reference.  The test tiles are Standard 630.
This weekend, I'm going to mix the slurries with various ingredients and colorants to see what results I can get.  I have been looking at old Albany slip recipes to get an idea of what to try and so far I've come up with various concentrations of iron, frits, whiting, spodumene, gerstley, and some colorants.  I'll post pictures of tests later this weekend.  I'm super excited at the prospect of something interesting coming out of this. 
For the geology/hydrology folks out there, after a bit of research, I believe this material is old lake bed that survived the Wisconsin age in the river valley.  Quoted from USGS Professional Paper 379, this sure sounds like what I found.  First a general description of the area then a section where they explain each layer:
In the valley of the Chemung River from Elmira to
Sayre, lake beds underlie the glaciofluvial deposits.
The lake sediments accumulated in the narrow bedrock
valley of the river and its principal tributaries, and they
are older than the Valley Heads moraine of Fairchild,
perhaps antedating the Olean substage (MacClintock
and Apfel, 1944).
Lake beds; silt, clayey, calcareous, light olive-
brown {2.57 5/4), massive. Lower contact
sharp, wavy; local relief ranges from 2 to 3
inches. About 200 ft to the south this unit
changes to calcareous medium to fine sand,
about 2 ft thick that rests disconformably on
the lake beds of unit 4_ _____________________ %
4. Lake beds; clay, silty, calcareous, gray (57 5/1),
stratified; form varves ranging from 2 to 4
inches in thickness and consisting of a relatively
thick layer of silty clay that grades upward into
a thin layer of clay; the contact between two
varves is sharper than that within a varve___
 

I've got some 630, but in  I'm upstate NY so you'd might as well have it shipped from a distributor who has it in stock.  If you can't find any or an acceptable substitute, send me a PM and we can work something out.  Not sure of your time frame needs at this point, but I figured I'd offer.
Happy new year everyone.

A wet tile saw would be ideal, but a masonry blade in a circular saw works well to cut alumina kiln shelves which are probably more dense than bisque.  I'd do it outside and run a small stream of water on the tile to keep the dust down and lubricate the blade.  I used to do that until I built a propane conversion kiln at which point I had to cut down 10 12x24 shelves to 10x22.  I then  bought a Harbor Freight tile saw and now can cut anything short of silicon carbide like butter.
As always, safety glasses and gloves and a respirator if cutting dry.  Good luck.

Greetings.
This may seem a bit simplistic, but in the last picture you posted the brown and black leads in the middle of the block coming from the thermocouple sure look they are not stripped.  I'd guess you torqued them down and have marginally intermittent connection where the screw cut through the wire's jacket.  Maybe it's the angle of the picture but it should be nothing but metal to metal contact at the bottom of that screw.  Just something easy to check that nobody brought up.  Good luck.

Could a moderator possibly sticky or pin this fix for this old Brent pedal issue to Mark C's Brent wheel fix-it section?  Brandon's solution works, the modification is simple and saved me a hundred bucks plus days of aggravation.  If you can solder and file/cut a little bit of plastic this is an easy fix to replace a part long thought extinct.
 I just acquired a 1975 Brent in excellent shape save the slide pot was shot.  I was about to pull the trigger on the $100 slide pot assembly from Amaco figuring it would fit (it won't I found out after some research) when I decided to see if I could get just the slide potentiometer.  I found this thread, ordered a couple of the 1M pots from the surplus place and had it fixed in probably 1/2 hour.  One thing that made my life easier was to use a Dremel with a small stone to sand the shaft of the slide pot and then switch to a tiny pointed burr to bore an ovalish slot in the opposite end for the mounting tab (which is on the slide side on this particular model).  I was afraid to hit 50 year old bakelite/plastic with anything like a chisel so a Dremel seemed like a good choice.  The new pot sits perfectly in the nest in the pedal casting and cutout in the plastic.  It should last another 50 years, but I have a spare now just in case
For the record, I believe mine is from 1975 as the serial number ends in 75, but here's a picture of the control box for comparison and anyone who may be in the same situation.
Brandon covered this thoroughly, but I'm also happy to share more pictures or descriptions of the modification if it would help folks.  Thanks.