Lunt,$34,Place,Dinner,esarjan.com,Silver,Sterling,Point,925,Vintage,/bibliomanism1636952.html,Antiques , Silver , Sterling Silver (.925) , Flatware Silverware,7-1/2",Lace Vintage Lunt Lace Virginia Beach Mall Point 925 Sterling Place 7-1 Dinner 2" Silver Lunt,$34,Place,Dinner,esarjan.com,Silver,Sterling,Point,925,Vintage,/bibliomanism1636952.html,Antiques , Silver , Sterling Silver (.925) , Flatware Silverware,7-1/2",Lace $34 Vintage Lunt Lace Point 925 Sterling Silver 7-1/2" Dinner Place Antiques Silver Sterling Silver (.925) Flatware Silverware Vintage Lunt Lace Virginia Beach Mall Point 925 Sterling Place 7-1 Dinner 2" Silver $34 Vintage Lunt Lace Point 925 Sterling Silver 7-1/2" Dinner Place Antiques Silver Sterling Silver (.925) Flatware Silverware
I will send practical posts like these (from thousands I have made). No ads or tracking. One-click unsubscribe. Answer to correspond with me. If you are already subscribed the email will confirm it.
Very low specific gravities on two commercial underglazes
AMACO and Crysanthos. 1.26 (67.5% water) and 1.22 (68% water)! The former is well below their recommended specific gravity of 1.4 (it still paints well but needs more coats, and more time to dry and apply them). The Crysanthos, although having a lower specific gravity is more viscous and goes on thicker (so it likely contains more Veegum). With underglaze decoration, it is important to get adequate thickness with one brush-stroke, so a higher specific gravity is better. This may be reason enough to consider making your own (by adding stain powders to a base and using Veegum CER to gel the slurry, slow drying and harden well at the dried state).
Tuesday 18th January 2022
Amaco underglazes can contain very high percentages of stain
Top are V-326 and V-388 underglazes, painted on and 04 ULTRATECH 2101 Spill Berm Connector fired. Although the layer is very thin the coverage is amazing and the brightness is stunning. This degree of brilliance is not possible unless the percentage of stain is very high. That explains whey these are double or triple the cost of a typical commercial glaze. The bottom mugs are clear-glazed and 05 fired, the one on the left with Amaco LG-10 and the one of the right is Spectrum 700. The latter produces better results over the underglaze and is more transparent and less yellowish on the body.
Tuesday 18th January 2022
Iron oxide as a fining agent to debubble a low fire transparent
These terra cotta clays were BUSSMANN CHCC 30A 600V FUSE HOLDER W/ FUSE (LOT OF 2) - USED - F fired at cone 04 and glaze fired to 04 using the 04DSDH schedule. The glaze is G1916Q, an expansion-adjustable cone 04 clear. That schedule alone is often enough to get transparent, defect free glazes in many situations. But not in this case. The solution was to add a fining agent. In this case we added 2% red iron oxide (to the top glaze). The particles of iron floating in the melt acted as a congregating points for bubbles, helping them to escape. And we got a bonus: a more interesting aesthetic. A 1% addition also worked, but not as well (we have settled on 2% iron and screening the glazes to 100 mesh). Screening out the larger particles slightly degraded the fining performance (so we have to accept the tiny specks). Iron does not always workin other situations. Other fining agents we have used at cone 6 do not work in this situation (e.g. 2% Zircopax, Alumina). Of course, this glaze will fire amber on a white body.
Context: G1916Q glaze fired at cone 03 and 04 on a terra cotta clay body, Glaze Bubbles, Terra cotta, Engine Exhaust Valve ITM RX9235, Drop-and-Soak Firing, Lot of 3 Biore Brightening Pore Strips Grapefruit + Citrus Essen
Sunday 16th January 2022
Red stain in matte and glossy bases. Which looks best?
The silky matte. 11% Mason 6021 encapsulated stain has been added to each. The one on the left is G2926B glossy base (it also has 2% zircopax as a fining agent for the micro-bubbles). But in the matte base on the right, G2934Y, no zircopax is necessary. It produces a stunning surface using this and other stains (including orange, yellow, black, purple), very pleasant to touch.
Sunday 16th January 2022
G1916Q glaze fired at cone 03 and 04 on a terra cotta clay body
The body is Plainsman L215. Both were thinly applied and fired using the 04DSDH schedule. The glaze has 2% iron oxide added and sieved to 80 mesh, this reddens the color and acts as a fining agent to reduce micro-bubble population. The one fired to cone 03 (left) is considerably stronger, better surviving the stress of successive impacts with a hammer. However, it has minute dimples in the surface, likely because it is having to clear bubbles originating from decompositions occurring in the body below (as it fires well above RED STITCH FITS PORSCHE 997 CARRERA 987 BOXSTER CAYMAN HANDBRAKE temperature). The mug on the right fired about 40F cooler, between cone 04 and 05, only slightly above bisque. The glaze surface is much better, almost crystal clear. Since the glaze fits well the mug has surprising strength, much better than a Alpinestars Missile V2 Ignition Mens 1-Pc Leather Suit Black/Whi piece with a poorly fitted glaze that shatters with one tap of a hammer. This one survived about ten whacks before a piece broke out! A big advantage of cone 04 and cooler is that ware can be fired on stilts, meaning you can glaze the whole thing, no bare clay is exposed. Again, I can only achieve this kind of glaze surface using the above-mentioned firing schedule.
Sunday 16th January 2022
G1916Q transparent on terra cotta body at cone 06, 05, 03
The body is Plainsman L215. We used the 04DSDH firing schedule. The glaze is inexpensive to make so we have a 2 gallon bucket. It has good dipping much like a 6 Pieces Richelieu Cabinet Hardware WROUGHT IRON Pull Backplate glaze so it is easy to apply quickly and evenly. For most terra cottas, body strength increases dramatically by cone 03. However the most transparent and glassy glaze surface happens at cone 06. Terra cotta bodies need to be RITTAL WMSPCS / WMSPCS (NEW NO BOX) fired fairly low (e.g. cone 06) to have enough porosity to work well with dipping glazes. After cone 06 they generate increasing amounts of gases (as various particle species decompose within), for this reason the glazes can have more micro-bubble clouding or tiny dimples in the surface. This glaze has 2% iron oxide added as a fining agent to remove the bubbles. That iron also reddens the color and variegates the surface somewhat. Even though the surface character at cone 03 is not a smooth, it has a natural charm, and the color is very rich. And that piece has stoneware durability and strength.
Sunday 16th January 2022
How to convert a dipping glaze to a brushing glaze
I have a jar of clear glaze that I mixed myself (10% yellow stain and 2% zircopax added to cone 03 G2931K clear). Commercial glaze producers make their lines of glazes like this. The cost of the dry materials: About $6. How can I make it paintable? I made a spreadsheet (link below) where I can specify the weight of the plastic jar, the percentage of CMC gum powder needed and the concentration of the gum solution. I just need to weigh the jar of glaze (without lid), weigh a teaspoon of the liquid glaze (lower left), dry it (upper right) and weigh the dry (lower right). After filling in these numbers the sheet tells me what weight to evaporate the jar to and how much gum solution to mix in. It paints on just like a commercial glaze. Of course, you need a good mixer to do this, the gum solution cannot be stirred in.
Context: CMC Gum, Where do I start in understanding glazes?, Improving a dipping glaze with a measured CMC addition, A case where glaze thickness really matters, CMC Gum Calculator - Worksheet, EWK Timing Chain Tensioner Holding Tool for VW Audi 1.8T 2.7T 2., Dipping Glaze
Tuesday 11th January 2022
Making a QRCode using porcelain pixels
I 3D-printed a stamper to create 9mm square pixels. Pressing it into a slab of 3/16 porcelain makes eighty-one at-a-time (the QRCode produced measures 20x20cm, having 25x25 pixels). The black porcelain has 5% Mason 6666 stain. Firing temperature was cone 6. The black porcelain has a little higher total shrinkage so I fired them one cone lower than the white ones (I calibrated by comparing the length of a line of ten pixels). The pixels dry and shrink and drop out of the stamper easily. The action of the stamper rounds the upper corners of each. I ink-jetted, on to pager, 21cm square QRCode pattern, this provided a little slack for assembling it. Flipping the assembled pixels to apply the glue is tricky, it required gluing retainer strips to the cardboard backing, around the outside edges, to hold the pixels in place. For the next one I plan to glue the pixels to a zero-fired-shrinkage clay tile, made from L4410P. A little silicon sealant on the tile and that will be suitable outdoors. What does this QRCode say? https://plainsmanclays.com.
Monday 10th January 2022
Why you need to make your own glazes, fire your own kilns
Are you a potter that depends on glazes made by others? Do you have your ware fired in someone else's kiln? Cannot mix clay body tests? Then the evolution of the quality and aesthetics of your work is being stunted. This mug is a good example of why. This is G3933, version 1 of an oatmeal we made by adding iron, rutile and tin to a 75:25 blend of our base matte and glossy glazes. It is crawling at a few sharp angles of the incised decoration, that means it needs a little CMC gum. And, it is not quite matte enough, we need to switch to an 80:20 blend. Third, the red-burning body gives better color at cone 5, and this glaze melts well in a C5DHSC slow cool firing. So I will include it with other cone 5 bodies and glazes we are testing (because I want to move down from cone 6 to save energy and elements). Finally, I would like the glaze a little darker so I will test increases in the rutile and iron. All of these changes are on my radar because I make my own glazes and have my own test kiln.
Sunday 9th January 2022
You may know Veegum T but do you know VeeGum CER?
The glaze in this jar was 'goop', impossible to paint on because it was too viscous. And it dried way too fast. Laguna mentions adding water so I measured the specific gravity (SG): 1.7. That is super-high, it took a 125cc addition to bring it down to 1.5, but it was still thick, dried even faster and brushing it on evenly was even harder. It was not obvious what to do next. It needed a lot more water (1.3-1.35 SG is normal to support multi-layer application), adding CMC gum and enough water to do that would produce an unusable watery and sticky slurry. Veegum CER to the rescue! It is a 50:50 mix of CMC gum and Veegum T. The former slows drying and hardens, the latter gels. So it can simply be added until the painting properties are right. And, a Veegum CER solution is easier to handle than one of CMC gum. This really worked! The brushing properties are just right and it gels nicely on standing. CER is also good for highly Wireless Car License Plate Backup Rear View Camera + 5" Monitor dipping glazes or others lacking in clay content (otherwise CMC might still be better).
Wednesday 5th January 2022
Use the contact form at the bottom on almost all the pages on this site.
Another Way to Support My Work
Subscribe to Insight-Live.com. It is about doing testing and development, not letting the information slip away. Starts at $15 for 6 months.
Login to your online account
Chemistry plus physics. Maintain your recipes, test results, firing schedules, pictures, materials, projects, etc. Access your data from any connected device. Import desktop Insight data (and of other products). Group accounts for industry and education. Private accounts for potters. Get started.
Download for Mac, PC, Linux
Interactive glaze chemistry for the desktop. Free (no longer in development but still maintained, M1 Mac version now available). Download here or in the Files panel within your Insight-live.com account.