Sep. 23, 2024
Electronic Components & Supplies
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SMD Resistor or Chip Fixed Resistor is one of the metal glass glaze resistors. It is a resistor made by mixing metal powder and glass glaze powder and printing on the substrate by the screen printing method. It is resistant to humidity and high temperature and has a low-temperature coefficient. SMD Resistor can greatly save the cost of circuit space and make the design more refined.
Abstract
SMD Resistor or Chip Fixed Resistor is one of the metal glass glaze resistors. It is a resistor made by mixing metal powder and glass glaze powder and printing on the substrate by the screen printing method. It is resistant to humidity and high temperature with a low-temperature coefficient. SMD Resistor can greatly save the cost of circuit space and make the design more refined. SMD is the abbreviation of Surface Mounted Devices, which is a special kind of SMT (Surface Mount Technology) element device. SMD resistors are usually called chip resistors.
Catalog
I How to identify SMD resistors codes?
1. Digital cable nominal method (generally used for rectangular chip resistors)
SMD resistor
The digital cable nominal method is to mark the resistance with digits on the resistor. Its first digit and second digit are significant digits, and the third digit represents the number of "0" added after the significant digit. No letters appear in this one. For example: "472 '" means "Ω"; "151" means "150".
The resistance value of the SMD resistor is usually directly marked on the surface of the resistor in digital form, so the resistance value of the reading resistor can be directly seen by the number on the resistor surface. There are generally three representation methods:
(1) Composed of three numbers, indicating that the tolerance of resistance is ± 5%. The first two digits are significant digits, the third digit represents the multiplying multiplier by zero, and the basic unit is Ω. For example, 103, 1, and 0 are valid numbers, just write them down, 2 means multiplying by zero, which is the power of 10 (in short, the third digit is the power of 10). So the resistance represented by 103 is the power of 10 × 10 = 10 × = Ω = 10KΩ
(2) Composed of four numbers, indicating that the tolerance of resistance is ± 1%. The first three digits are significant digits, and the fourth digit represents a multiplier by zero (that is, the number means the power of 10). For example, , 150 is a significant number, write it down directly, 2 represents the power of 10. So the resistance of is the square of 150 × 10 = 150 × 100 = Ω = 15KΩ
(3) Composed of numbers and letters, such as 5R6, R16, etc. Here only need to replace R with a decimal point.
5R6 = 5.6R = 5.6Ω R16 = 0.16R = 0.16Ω
It should be noted here that "R" is the expression of resistance and "Ω" is the expression of resistance unit. In daily life, we may not mix the two, but in industrial production, the boundary between the two is very vague.
Here you can use Utmel's resistor code calculator to quickly determine the resistance value of an SMD resistor using the markings found on the resistor.
2.Nominal color ring method (generally used for cylindrical fixed resistors)
SMD resistors are the same as general resistors, and most of them use four rings (sometimes three rings) to indicate their resistance. The first ring and the second ring are significant digits, and the third ring is the magnification (color ring codes are shown in Table 1). For example: "Brown Green Black" means "15Ω"; "Blue Gray Orange Silver" means "68kΩ" with tolerance ± 10%.
3.E96 digital code and letter mixed nominal method
The mixed nominal method of digital codes and letters also uses three digits to indicate the resistance value, that is, "two digits plus one letter", where two digits represent the E96 series resistance code. Its third digit is the magnification expressed by letter code (shown in Table). For example: "51D" means "332 × 103; 332kΩ"; "249Y" means "249 × 10-2; 2.49Ω".
II SMD resistors size
Surface-mount resistors are standardized in shape and size. Most manufacturers use the JEDEC standard. The size of the SMD resistor is represented by a digital code, such as . This code contains the width and height of the package. Therefore, in the example of the Imperial code, this means that the length is 0.060 "and the width is 0.030". This code can be given in English or metric units, usually using English codes to indicate package size more frequently. In contrast, in modern PCB design, metric units (mm) are more commonly used, which may cause confusion. In general, you can assume that the code is in English units, but the size unit used is mm. The size of the SMD resistor depends mainly on the required power rating. The following table lists the dimensions and specifications of common surface-mount packages.
(in)
(mm)
(L)(mm)
(W)(mm)
(t)(mm)
an (mm)
b(mm)
0.60±0.05
0.30±0.05
0.23±0.05
0.10±0.05
0.15±0.05
1.00±0.10
0.50±0.10
0.30±0.10
0.20±0.10
0.25±0.10
1.60±0.15
0.80±0.15
0.40±0.10
0.30±0.20
0.30±0.20
2.00±0.20
1.25±0.15
0.50±0.10
0.40±0.20
0.40±0.20
3.20±0.20
1.60±0.15
0.55±0.10
0.50±0.20
0.50±0.20
3.20±0.20
2.50±0.20
0.55±0.10
0.50±0.20
0.50±0.20
4.50±0.20
3.20±0.20
0.55±0.10
0.50±0.20
0.50±0.20
5.00±0.20
2.50±0.20
0.55±0.10
0.60±0.20
0.60±0.20
6.40±0.20
3.20±0.20
0.55±0.10
0.60±0.20
0.60±0.20
Package and size table
III SMD resistors testing method
1. Grounding resistance test requirements: a. AC working grounding, resistance should not be greater than 4Ω; b. Safe working grounding, resistance should not exceed 4Ω; c. DC working grounding, resistance should be determined according to the specific requirements of the computer system; The patch resistance of the lightning protection ground should not be greater than 10Ω; e. If the shielding system uses joint grounding, the grounding resistance should not be greater than 1Ω.
2. SMD resistor tester
ZC-8 ground resistance tester is suitable for measuring the resistance value of various power systems, electrical equipment, lightning rods, and other grounding devices. It can also measure the resistance value and soil resistivity of low-resistance conductors.
ZC-8 ground resistance tester
3. The work of this instrument is composed of a hand-cranked generator, current transformer, slide wire resistor, and galvanometer. All the mechanisms are installed in the plastic shell, and the outer shell is easy to carry. The accessories include auxiliary probe wires, etc., which are installed in the accessory bag. Its working principle uses the reference voltage comparison formula.
4. Check whether the tester is complete before use. The tester includes the following devices: 1. One ZC-8 grounding resistance tester 2. Two auxiliary grounding rods 3. Three wires, each of which is 5m, 20m, and 40m
5. Use and operation
(1) When measuring the resistance of an SMD resistor, the E terminal button on the instrument is connected with a 5m wire, the P terminal button is connected with a 20m wire, and the C terminal button is connected with a 40m wire. The other end of the wire is connected to the ground electrode E&#;, potential probe P&#; and current probe C&#;, and E&#;, P&#;, C&#; should be kept in a straight line with a distance of 20m.
When the wiring diagram when the chip resistance is greater than or equal to 1Ω, connect the two E-terminal buttons on the meter together. Related pictures on this topic are as follows:
Want more information on metal oxide film resistor? Feel free to contact us.
The wiring diagram when the chip resistance is greater than or equal to 1Ω;
When the chip resistance is less than 1Ω, connect the two E-terminal button wires on the instrument to the ground body under test to eliminate the additional error introduced by the resistance of the connecting wire during the measurement.
The wiring diagram when the chip resistance is less than 1Ω
(2) Operation steps
1) All wiring at the instrument end should be correct.
2) The connection between the instrument and the ground electrode E&#;, potential probe P&#;, and current probe C&#; should be in firm contact.
3) After the meter is placed horizontally, adjust the mechanical zero position of the galvanometer, and return to zero.
4) Set the "Magnification Switch" to the maximum magnification and gradually increase the speed of the crank handle to 150r / min. When the galvanometer pointer deflects in a certain direction, turn the dial to restore the galvanometer pointer to the "0" point. At this time, the reading on the dial multiplied by the magnification scale is the measured resistance value.
5) If the dial reading is less than 1, the galvanometer pointer is still not balanced, and the magnification switch can be set to the next lower magnification until it is adjusted to full balance.
6) If the pointer of the meter galvanometer is found to be jittery, the speed of the crank can be changed to eliminate the jitter.
Circuit and physical diagrams
IV Tolerance
What is a precision SMD resistor? The precision SMD resistor means that the tolerance of the chip resistor is relatively small. It is generally called tolerance of 1%. The minimum error can reach 0.01%. The temperature coefficient is as low as ± 5ppm / °C, which is rarely achieved by the industry: It can be applied to precision instruments, communication electronic products, and portable electronic products. So many people will ask if the chip resistance is so small, can it be distinguished if 5% and 1% are not tested? So below we compare the difference between 5% and 1% chip resistors.
The 5% series SMD resistors are represented by 3 characters: in this method, the first two digits represent the effective digits of the resistance value, and the third digit represents the number of "0" that should be added after the effective number. When the resistance is less than 10Ω, R is used to indicate the position of the decimal point of the resistance value in the resistor code. This notation is usually used in a resistance series with a resistance value error of 5%. For example, 330 means 33Ω instead of 330Ω; 221 means 220Ω; 683 means Ω or 68kΩ; 105 means 1MΩ; 6R2 means 6.2Ω.
The 1% series precision SMD resistors are represented by 4 characters: the first 3 digits of this notation represent the effective digits of the resistance value, and the fourth digit represents the number of 0s that should be added after the effective digits. When the resistance is less than 10Ω, R is still used in the code to indicate the position of the decimal point of the resistance value. This representation method is generally used in the precision resistance series with a resistance error of 1%. For example: means 10Ω; means 100Ω; means Ω, or 49.9kΩ; means Ω or 147kΩ; 0R56 means 0.56Ω.
The surface of the SMD resistors is engraved with letters. If there are only three digits, the error is 5%. If there are four digits, the error is 1%.
V Selection of SMD resistors
The application of surface assembly technology (SMT) is very common, and the proportion of electronic products assembled by SMT has exceeded 90%. With the development of small-scale SMT production equipment, the application scope of SMT is further expanded, and aerospace, aerospace, instrumentation, machine tools, and other fields are also using SMT to produce various small-scale electronic products or components.
Electronic product developers often use SMD devices to develop new products. In recent years, maintenance personnel has also begun to repair a large number of electronic products assembled by SMT technology.
The model of the SMD resistor is not uniform and is set by each manufacturer, and the model is particularly long (composed of more than a dozen letters and numbers). If the various parameters and specifications of the SMD resistor can be correctly presented when purchasing, then the required resistor can be easily purchased (or ordered).
There are 5 parameters for SMD resistors, namely size, resistance, tolerance, temperature coefficient, and packaging.
1. Size
SMD resistors generally have 7 sizes, which are expressed by two size codes. A size code is an EIA (American Electronics Industry Association) code represented by 4 digits. The first two digits and the last two digits indicate the length and width of the resistor in inches respectively. The other is the metric code, which is also represented by 4 digits in millimeters. Different size resistors have different power ratings.
2. Resistance
The nominal resistance is determined by the series. Each series is divided by the tolerance of the resistance (the smaller the tolerance, the more the resistance value is divided), and the most commonly used is E-24 (the tolerance of the resistance value is ± 5%).
On the surface of the SMD resistor, three digits are used to represent the resistance value, in which the first and second digits are valid numbers, and the third digit represents the number followed by zero. When there is a decimal point, use "R" to represent, and occupy one significant digit.
3. Tolerance
The tolerance of SMD resistor (carbon film resistor) has 4 levels, namely F level, ±1%; G level, ±2%; J level, ±5%; K level, ±10%.
4. Temperature coefficient
The temperature coefficient of the SMD resistor has two levels, namely w level, ±;200ppm / &#;; X level, ±100ppm / &#;. Only resistors with tolerance class F are grade x, while resistors with tolerances of other grades are generally class w.
5. There are mainly two kinds of packaging: bulk and ribbon roll.
The working temperature range of the SMD resistors is -55-+125 &#;. The maximum working voltage is related to the size: is the lowest, , and are 50V, is 150V, and other sizes are 200V.
The digits on the surface of the SMD resistor are used to represent the resistance characters arranged horizontally and are specified to be represented by three digits, where the first two digits are valid digits and the third digit is an exponent of 10. For example: 473 means 47 × 103 = 47 kΩ. If the second character on the surface of the resistor used to indicate the resistance value is the letter R, it represents the decimal point, for example, 5R1 means the resistance value is 5.1 Ω.
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Break your addiction to online recipes that don't work or bottled expensive glazes. Learn why glazes fire as they do. Why each material is used. How to create perfect dipping and drying properties. Even some chemistry.
Likely you have already watched lots of Youtube videos and found there are many ways to approach ceramics. Hobbyists and artists often think of clay as a "canvas" and glazes as "paints", they imagine showcasing their painting skills with artistic designs, they enter with an expectation of few issues and creating the exact colors and surfaces they want (from the expensive bottled glazes they assume won't craze or shiver on their bodies). Others enter with the desire to mix their own clays, formulate their own glazes, build their own kilns and they relish the new things learned with each firing. These often embark on mixing recipes found on Pinterest, Glazy or Facebook, hoping they will somehow magically work.
In industry the prevailing culture is more and more toward dependence on suppliers, getting by with the least knowledge possible. We are often amazed at how little knowledge technicians working in huge factories sometimes have!
You may have realized by now that this site is dedicated to fighting these cultures (which we personify as "the glaze dragon"). Understanding glazes better can empower you in many ways.
It is about balance in the chemistry, not saturating it with heavy metals, about firing in the way appropriate for the recipe, about liner glazing. About knowing how to adjust. It&#;s not rocket science. It&#;s about not trusting anything with significant percentages of colorants (or things like barium carbonate, lithium carbonate), even commercial glazes, without doing simple leach testing. Just get started taking the new approaches mentioned here and you will become opinionated about leaching in no time!
If you are going to make ceramic ware, put good glazes on it. Remember, a glaze is a lot more than one that just has a pleasing fired appearance. There is no one-glaze-that-works-for-everyone. We cater to people that want to start out right, or have been kicked around long enough that they are ready to learn why, they want to "understand". You will never likely get the glazes you really want until you formulate or adapt them yourself.
The left glaze is "stretched" on the clay so it cracks (it calculates to a high thermal expansion so this is not a surprise). This usually appears after firing but can appear years later. When the lines are close together like this it is more serious. If the effect is intended, it is called "crackle" (but no one would intend this on functional ware). The one on the left calculates much lower - and stays uncrazed indefinitely. Potters, hobbyists and artists invariably bump into this issue whether using commercial glazes or making their own.
"Art language" solutions don't work, at least some technical words are needed to even understand what this simply is: A mismatch in the thermal expansions of glaze and body. Most ceramics expand slightly on heating and contract on cooling. Even though the amount of change is very small, ceramics are brittle so if a glaze is stretched on the ware, it will crack to relieve the stress. Crazing appears when ceramic is cooled and the glaze contracts more than the clay to which it is rigidly attached.
The original cone 6 recipe, WCB, fires to a beautiful brilliant deep blue green (shown in column 2 of this Insight-live screen-shot). But it is crazing and settling badly in the bucket. The crazing is because of high KNaO (potassium and sodium from the high feldspar). The settling is because there is almost no clay. Adjustment 1 (column 3 in the picture) eliminates the feldspar and sources Al2O3 from kaolin and KNaO from Frit (preserving the glaze's chemistry). To make that happen the amounts of other materials had to be juggled. But the fired test revealed that this one, although very similar, is melting more (because the frit releases its oxides more readily than feldspar). Adjustment 2 (column 4) proposes a 10-part silica addition. SiO2 is the glass former, the more a glaze will accept without losing the intended visual character, the better. The result is less running and more durability and resistance to leaching.
Three cone 6 commercial bottled glazes have been layered. The mug was filled with lemon juice overnight. The white areas indicate leaching has occurred! Why? Glazes need high melt fluidity to produce reactive surfaces like this. While such normally tend to leach metals, supposedly the manufacturers were able to tune the chemistry enough to pass tests. But the overlaps interact, like drug interactions they are new chemistries. Cobalt is clearly leaching. What else? We do not know, these recipes are secret. It is better to make your own transparent or white liner glaze (either as a dipping glaze or brushing glaze). Better to know the recipe to have assurance of adherence to basic recipe limits.
Are commercial glazes really guaranteed food safe? When manufacturers claim adherence to standards like ASTM D- what are they saying? The small amounts of liquid glazes are safe for the artist to brush on. They are not making claims about leaching on finish ware.
To make a low SG version of GBL I have already weighed out a 340g batch (it contains 5g each of Veegum and CMC gum to gel the slurry and slow the drying). I use 440g of water initially (adjusting that according to experience in brushing behaviour). After shake-mixing all the powder in the plastic bag I pour it into the water on low speed and finish with 20 seconds on high speed. This produces a low specific gravity brushing glaze, it just fills this 500ml jar. In subsequent batches, I adjust the Veegum for more or less gel and the CMC for slower or faster drying. Later I also assess whether the CMC gum is being degraded by microbial attack - often evident if the slurry thins and loses its gel. Since each glaze recipe responds differently and changes differently over time, good notes are essential. We are working on dozens of these at any given time, each is code-numbered in our group account at Insight-live.com. This is so worthwhile doing that I make quality custom labels for each jar!
Yes. In this case the entire outside and inside of the mug need an evenly applied coat of glaze. For hobby this makes sense. But in production cover brushing makes less sense. The right pail has 2 gallons of GY base with 10% Cerdec yellow stain: $135. Cost of brushing jars with the same amount: $600+! And each jar logs 10-15 minutes painting time plus waiting between coats. The one in the pail is a true dipping glaze (unlike many commercial ones that dry slowly and drip-drip-drip). This one dries immediately after dipping in a perfectly even layer (if mixed according to our instructions). And a bonus: This pail can be converted to brushing or base-layering versions using CMC gum.
This is a clear glaze (GK) with 10% purple stain (Mason ). The mugs are cone 03 porcelain (Zero3). The mug on the left was dipped (at the bisque stage) into a slurry of the glaze (having an appropriate specific gravity and thixotropy). The glaze dried in seconds. The one on the right was painted on (two layers). Like any paint-on glaze, it contains gum (1% CMC). Each layer required several minutes of application time and fifteen minutes of drying time. Yet it is still not evenly applied.
Brushing glazes are great sometimes. But they would be even greater if the recipe was available. Then it would be possible to make it if they decide to discontinue the product. Or if your retailer does not have it. Or to make a dipping glaze version for all the times when that is the better way to apply. The glaze manufacturer did not consider glaze fit with your clay body, if they work well together it is by accident. But if you have transparent and matte base recipes that that work on your clay body then adding stains, variegators and opacifiers is easy. And making a brushing glaze version of any of them. Don't have base recipes??? Let's get started developing them with an account at insight-live.com (and the know-how you will find there)!
These are two pallets (of three) that went on a semi-trailer load to a Plainsman Clays store in Edmonton this week. They are packed with hundreds of bags of powders used to mix glazes. More and more orders for raw ceramic materials are coming in all the time. Maybe you are using lots of bottled glazes but for a cover or a liner glaze it is better to mix your own. And cheaper! And there are lots of recipes and premixed powders here to do it. One of the big advantages is that when you dip ware into a properly mixed slurry it goes on perfectly even, does not run and dries on the bisque in seconds. No bottled glaze can do that.
There is a direct relationship between the way ceramic glazes fire and their chemistry. These green panels in my Insight-live account compare two glaze recipes: A glossy and matte. Grasping their simple chemistry mechanisms is a first step to getting control of your glazes. To fixing problems like crazing, blistering, pinholing, settling, gelling, clouding, leaching, crawling, marking, scratching, powdering. To substituting frits or incorporating available, better or cheaper materials while maintaining the same chemistry. To adjusting melting temperature, gloss, surface character, color. And identifying weaknesses in glazes to avoid problems. And to creating and optimizing base glazes to work with difficult colors or stains and for special effects dependent on opacification, crystallization or variegation. And even to creating glazes from scratch and using your own native materials in the highest possible percentage.
These are cone 6 Alberta Slip recipes that have been brushed onto the outsides of these mugs (three coats gave very thick coverage). Recipes are GA6-C Rutile Blue on the outside of the left mug, GA6-F Alberta Slip Oatmeal on the outside of the center mug and GA6-F Oatmeal over GB black on the outside of the right mug). These are examples of high specific gravity brushing glazes. One-pint jars are made using 500g of glaze powder, 280g of water and 75g of Laguna CMC gum solution (equivalent to 1%). Because no Veegum is being used this blender mixes to a slurry of super high 1.6 specific gravity (SG). Commercial glazes have a much lower specific gravity (thus much more water), giving better paintability and gelling but requiring more coats. Still, this approach is good for Alberta Slip because it is highly plastic and comprises the bulk of the recipe. The gum removes the need to roast 50% of it and the plasticity of the Alberta Slip helps suspend the slurry.
These cone 6 porcelain mugs are hybrid. Three coats of a commercial glaze painted on the outside (Amaco PC-30) and my own liner glaze, GB, poured in and out on the inside. When commercial glazes (made by one company) fit a stoneware or porcelain (made by another company) it is by accident, neither company designed for the other! For inside food surfaces make or mix a liner glaze already proven to fit your clay body, one that sanity-checks well (as a dipping glaze or a brushing glaze). In your own recipes you can use quality materials that you know deliver no toxic compounds to the glass and that are proportioned to deliver a balanced chemistry. Read and watch our liner glazing step-by-step and liner glazing video for details on how to make glazes meet at the rim like this.
This is what you need to be independent, to create your own manufacturing company in your garage in Some of the prices are "instead of" rather than additive. There are many approaches to glazes, the more you are willing to learn the better you will be able to make your own (and save a lot). We recommend the cone 6 range using a small test kiln (like this 220v ConeArt GX119, don't scrimp on this, go for quality and the practicality of a Genesis controller). A kiln you can fire often and inexpensively is a key enabler to learning, developing techniques, products, designs, durable and decorative surfaces, solving problems. It can be fired multiple times a day. And it is big enough for mugs and similar sizes. It will get you into the habit of using some of your creativity for experimenting. It will give you the successes early on that will inspire you to press on learning. When you are ready, then get a big kiln and hit-the-ground-running. This potter's wheel is the best available and will last a lifetime, these often appreciate in value over time. And, build yourself a good plaster table. You will use it constantly. Not shown here is a propeller mixer, also an important tool. And you will need a sink equipped with a sink trap (Gleco Trap).
Books and web pages with flashy pictures are the centrepiece of an addiction-ecosystem to recipes that often just don't work. Maybe these are "tried" by a lot of people. But are they "true"? Most are so-called "reactive glazes", outside normal practice - to produce visual interest they run, variegate, crystallize, pool, break, tint, go metallic, etc. But this happens at a cost. And inside special procedures and firing schedules that need explaining. It is not obvious these are understood by the recipe authors or sharers. And these recipes are dated and contain troublesome and unavailable materials. We use frits now to source boron. Stains are superior to raw colorants, even in glazes like this. Many of these will craze badly. And many will not suspend in the bucket. And will run during firing. Reactive glazes have other common issues: Blistering, leaching, cutlery marking, fuming. Trying colors in differing amounts in different base recipes is a good idea. But the project is most beneficial when it shows color response in terms of quality recipes of contrasting chemistries. The point of all of this: Understand a few glazes and develop them, rather than throwing spaghetti against the wall hoping something sticks. Commercial reactive glazes are an alternative also.
Material prices are sky rocketing. And, the more complex your supplier's supply chain the more likely they won't be able to deliver. How can you adapt to coming disruption, even turn it into a benefit? Learn to create base recipes for your glazes and even clay bodies. Learn now how to substitute frits and other materials in glazes (get the chemistry of frits you use now so you are ready). Even better: Learn to see your glaze as an oxide formula. Then calculate formula-to-batch to use whatever materials you can get. Learn how to adjust glazes for thermal expansion, temperature, surface, color, etc. And your clay bodies? Develop an organized physical testing regimen now to accumulate data on their properties, learn to understand how each material in the recipe contributes to those properties. Armed with that data you will be able to adjust recipes to adapt to changing supplies.
Material prices were sky rocketing (and still are). Prepared glaze manufacturers have complex international supply chains. Now might be the time to start learning how to weigh out the ingredients to make your own. Armed with good base glazes that fit your clay body (without crazing or shivering) you will be more resilient to supply issues. Add stains, opacifiers and variegators to the bases to make anything you want. That being said, ingredients in those recipes may become unavailable! That underscores a need to go to the next step and "understand" glaze ingredients. And even improve and adjust recipes. It is not rocket science, it is just work accompanied by organized record-keeping and good labeling.
This recipe is from page 2 of the booklet: "15 Tried & True Cone 6 Glaze Recipes". Click the following code, G, to see more information on how it compares with G and GZ1 mattes. This flow test and these test tiles were in the same kiln, fired at cone 6 using our PLC6DS schedule. The defining characteristic of N505 is its extreme melt fluidity - it runs because it is overtired at cone 6. Still, the surface on the tile (lower right) is arguably more interesting than G. Some felt pen marking reveals why: The micro surface is much rougher. To its credit, although it does stain easier, it can still be cleaned with effort.
From the chemistry, shown on Insight-Live side-by-side screenshot. It has very low Al2O3 and SiO2 - that turns on some red and yellow lights. One could hope to have melt fluidity and great functionality, but they pretty well never go together. This glaze should fire glossy - the 6% magnesium carbonate is the mechanism of the matteness - MagCarb is super refractory, it may not be dissolving in the. melt. The glaze should cutlery mark (although it seemed hard in our testing). Most important, low Si:Al levels always carry the risk of leaching - exercise caution adding any significant percentage of heavy metal pigments. Crazing is another possible issue over melted glaze.
You will see examples of replacing unavailable materials (especially frits), fixing various issues (e.g. running, crazing, settling), making them melt more, adjusting matteness, etc. Insight-Live has an extensive help system (the round blue icon on the left) that also deals with fixing real-world problems and understanding glazes and clay bodies.
These are cone 6 commercial glazes made by a popular US manufacturer. The body is a cone 6 casting porcelain made by another popular manufacturer. Zoom the photo to see they are all crazing! Which company is at fault? Neither is able to assure a match of their product to others. The pattern we see here points the finger first at the body. Mid-fire porcelains craze glazes if they lack sufficient silica (20% is minimum). It is difficult for manufacturers to achieve this since more feldspar, at the expense of silica, is needed to vitrify the body. And the recipe of the porcelain is proprietary. You already have a propeller mixer, scale and containers so why not mix your own porcelain from a recipe (e.g. LD or derivative)? Glaze fit is also a matter of chance. Mixing your own transparent brushing glaze or dipping glaze would provide another level of control (e.g. GB or derivative).
I used Veegum to form 10 gram GBMF test balls and fired them at cone 08 (F). Frits melt really well, they do have an LOI like raw materials. These contain boron (B2O3), it is a low expansion super-melter that raw materials don&#;t have. Frit (glossy) and (silky matte) are balanced-chemistry bases (just add 10-15% kaolin for a cone 04 glaze, or more silica+kaolin to go higher). Consider Frit a man-made low-Al2O3 super feldspar. Its high-sodium makes it high thermal expansion. It works really well in bodies and is great to make glazes that craze. The high-MgO Frit (made for the abrasives industry) has a very-low expansion, it is great for fixing crazing glazes. Frit is similar to but without Al2O3. Use it where the glaze does not need more Al2O3 (e.g. already has enough clay). It is no accident that these are used by potters in North America, they complement each other well (equivalents are made around the world by others). The Gerstley Borate is a natural source of boron (with issues frits do not have).
These GLFL tests and GBMF tests for melt-flow compare 6 unconventionally fluxed glazes with a traditional cone 6 moderately boron fluxed (+soda/calcia/magnesia) base (far left Plainsman GB). The objective is to achieve higher melt fluidity for a more brilliant surface and for more reactive response with colorant and variegator additions (with awareness of downsides of this). Classified by most active fluxes they are:
G - Moderate zinc, no boron
G - High-soda+lithia+strontium
G - High boron+soda (Gerstley Borate based)
GA - chemistry sourced from frits
G - Boron+zinc+lithia
GB - Soda+zinc+strontium+boron (mixed oxide effect)
This series of tests was done to choose a recipe, that while more fluid, will have a minimum of the problems associated with such (e.g. crazing, blistering, low run volatility, susceptibility to leaching). As a final step the recipe will be adjusted as needed. We eventually evolved the GB, after many iterations settled on GE or GF as best for now.
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