Metal Casting Zone Info Blog

Posts Tagged ‘Clay’

Bangladesh Village Metal Casting

Preparing the scrap metal, the furnace and crucibles for casting and explaining a bit about the mould making process. The firing process and casting takes several hours and unfortunately we couldn’t stay. Rice husk is mixed with the clay to make it more refactory. Old crucibles are used to cap the new ones. A combination of brass, copper and zinc is used to make a ‘bell metal’. Both mould and crucible are placed in the furnace, when the metal is molten, both are removed from the furnace, a hole is pierced in the side of the crucible and the metal is poured.
Thanks to Riaz and Britto.

Dhamrai Metal Casting

Breaking the layers of clay away from a lost wax casting in brass at Dhamrai metal casting.

Your Silver Clay Project Will Be Flawless With These Tips

Silver clay? Whatever is that?

Silver clay, precious metal clay, art metal clay, and art clay silver are all different terms and types of “clay” that may be magically turned into gold and silver.

These innovative metal clays were introduced to the North American market in the nineties. Jewelry enthusiasts and hobbyists can now shape and mold precious metal as easily as clay.

Making jewelry naturally has a long history. The difference today is that you now do not have to bang or cast your metal to make jewellery if you don’t wish to. Silver clay now makes it feasible to make real metal forms without these traditional methods.

Here is how metal clay functions. Art metal clays are composed of fine metal particles suspended in an organic binder. This binder lets you mould and shape the clay as you would potter’s clay. When you are happy with the form, you let your project dry for no less than twenty-four hours ( or even more ). You then fire it in a kiln or by employing a hand torch. The binder burns away, leaving the fused metal behind in the shape you formed it.

Before you grab a lump of silver clay and go at it though, you will need to keep 1 or 2 rules under consideration. Silver clay isn’t cheap, so you don’t want to waste it.

Silver Clay Tips

Here are a bunch of tips for working with silver clay :

*Metal clays shrink 10-30% when fired. Be sure to check your package for shrinkage levels particularly if you are making rings or other objects that must be exact fits.

*Not all metal clays can be hand torch fired. If you won’t be employing a kiln be certain to check that your kind of silver clay is “low fire”.

*Only small pieces should be torch fired. Pieces bigger than 25g should be kiln fired.

]]>

*Silver clay is expensive. The gold version especially is very high-priced. Be certain to shop carefully and follow instructions carefully so you don’t burn your money fruitlessly.

*Metal Clay simply takes on impressions of other objects ( and fingerprints too ). Experiment with different textures and objects to make imprints onto the wet clay.

*Gemstones that may stand up to the heat of firing can be set into the wet clay.

*Be sure to let your metal clay dry fully before firing. Firing damp clay won’t work and you will not be a happy camper.

*Metal clays are sticky to the touch so be sure to coat everything with a thin film of olive oil or other release agent. This suggests coat your hands, your tools, and work surface. Just a touch of oil will do, so don’t go too far.

*You can improve drying time by placing your piece in a low heat stove. ( 150-200 degrees fahrenheit ). Pieces finely than your palm usually take approximately twenty-four hours to fully dry and toughen without the cooker treatment.

*Sand your dried and hardened piece before firing. If you do not like fingerprints, you will not be well placed to remove them after firing.

*Metal clay is soluble and can be fell with water. Keep a tiny bowl of water or a spritzer handy while you’re employed. If it starts to dry out while working, you can add a bit of water to dampen it.

*Buying smaller packages beats larger as you will not have to fret about the entire block drying out. The price difference is immaterial, and you may waste extra cash by needing to thru out old dried out clay.

*You can extend the working time of your metal clay by adding a drop or 2 of glycerin ( available at drug stores ) to your newly opened package of silver clay. To use : make a depression with your thumb in the clay, and add a drop or 2 of glycerin. Fold the clay a couple of times to mix in the glycerin, then spritz with water. Wrap in plastic wrap and let sit so the clay can absorb the glycerin. When you work with the clay the following day, use as always. This trick will extend the working time, but also extends the drying time required before firing.

*If you see a blackish mildew, do not be disturbed. This will burn away when firing. This mildew takes place when you use regular tap water to moisten the clay.

*Playing cards make great “spacers” when rolling out clay to an even thickness. Just stack cards on each side of the clay, then use your roller to roll out the clay between the cards.

*To store metal clay between uses, be certain to spritz with water and wrap it well with plastic wrap.

*different clays have different firing temperatures so be certain to match your firing temperature to your clay type.

*Once fired, you must brush and burnish it to get a great shine. First brush well with a stiff brush to loosen any ash or residue, then rinse with water. Then you’ll be wanting to burnish the metal to compress it, make it smoother, and shinier. Utilise a burnishing tool made from agate or metal for this. The tool has a smooth face and pointy tip for burnishing the more detailed areas.

*You can dunk the piece in water after firing to chill it quickly .

*Firing you clay too shortly, at too low a temperature, or for too short a time may cause your project to crack. Firing for too much time may melt some of the detail.

Now you have some silver clay suggestions, I bet you are psyched. You need to work with this innovative material now! What will you make first?

Find More Precious Metal Casting Articles

Chimeneas: The Essential Backyard Equipment

Chimeneas are an alternative to fire pits having similar functions. They are used to provide warmth outdoors and also used for cooking purposes. They possess a huge round bottomed flask-like structure with an exception of a huge opening at one of its sides that acts as the fireplace. They originated thousands of years ago in Mexico and were used by their tribesmen to provide heat on cold winter nights as also to bake breads and other foodstuffs. They often decorate the patio or the deck as ornamental structures when not in use. They are available in different sizes, shapes and styles.

They are provided with a narrow smoke outlet at the top that ensures the release of smoke upwards without causing hindrance to the surrounding environment. They are usually available in metal or clay. Amongst metals, cast iron, copper and cast aluminum are commonly used. The metal versions of chimeneas are usually more durable than the clay version of it simply because clay tends to crackle and crumble when comes across high impact force on its surface. Most basic designs have dimensions that measure up to five feet lengthwise and two feet breadth wise.

They serve so many purposes that they are just the essential add on to your patio or deck. Other than providing heat to the surrounding and being useful in grilling and roasting meat or baked potatoes they can also be used to get rid of mosquitoes by the use of certain varieties of wood known as Pinon wood or Mesquite. They are a great addition to the pool areas, gardens and backyards. You can have family gatherings and also organize parties with friends at the outer portion of your house during the winter season without any hassle by using these proficient and dependable heaters.

Since they come in varied designs, in seasons like summer when you might not need the chimeneas for warmth, they can be used as ornamental structures. All you have to do is cover the top of the chimenea to protect it from dust or other unwanted substances settled in that space. Even if you may have placed the chimenea in a place not prone to fire accidents it is very important that you take necessary precautions when using them. You need to be equipped with fire extinguishers or some water source when you use the chimenea for cooking and grilling purposes. Usually larger chimeneas are a better choice because the bigger the space through which you have to place wood the better it is to handle and manage the fire and you don’t have to chop the wood too fine to fit into smaller holes. Thus having a chimenea can be quite handy all year around for your outdoor living space convenience.

Grantham History

The Spotted Cow began life as a beer house, before being re-built in its present form to become a Public House, at the turn of the 20th century.  The property eventually received its full license after The Artichokes Inn on Swinegate was closed in 1921.  The property received heavy damage during World War II after a Nazi bomb exploded in the street outside, causing damage to the front windows and removing most of the roofing tiles.  John Smiths Brewery bought the property is 1971 from Warwick & Richardson Brewery of Newark.  Circa 2002 it became an Indian Restaurant before being bought in a dilapidated state in December 2008 by Ian Carroll Limited, builder in Lincolnshire , with the intention of converting the property into two high grade offices and two luxury apartments.

The property at the present moment is undergoing extensive renovation, though it is to be noted that the external features as far as possible are going to be in keeping with what the property was like during the middle of its life.  However the internals of the property will be modified to incorporate two offices on the ground floor and two apartments on the first floor.  Allow us to begin firstly by considering the external façade of the property.

To try and maintain the property to be in keeping with what it was like previously historical research was undertaken.  Surprisingly, even with it being a social hub in the Southern end of Grantham, very few photographs could be obtained, and very few facts about the property could be found, the most being summarised in the introduction of this article.  However from the photographs that was found at least one was of value.  Firstly the chimneys were removed to aid in maintenance of the property in later years, but also more importantly they were of value as the bricks were saved, and used to make good any alterations to the external of the property.  The original roof tiles were removed and the entirety of the pitched roof section re-felted and battened.  The next major step in the project was the choice of roof tile that was to be used to re-tile the roof.  Here again major effort was inputted.  The choice was narrowed down through the reasons outlined previously, leaving a replacement clay tile as the only choice.  Today only two major tile companies still manufacture the modern alternative to the original clay tile, Sandtoft and Marley Eternet.  The main deciding factor between these companies was that one choice had colour consistency through out the tile, therefore this was chosen.  To be in keeping with Public House tradition and to also highlight the building from those surrounding it, a mixture of single camber red smooth clay tiles and four rows of red smooth clay club tiles in the middle, run through the entirety of the roof.  The ridge tiles again were specifically chosen to highlight the building, these being two hole crested ridge, these being chosen to offset the loss of the chimneys.  The rainwater gutters and down pipes were replaced like for like with similar cast iron products.

The external woodwork of the building was another key issue.  With the frontage of the building sporting mock Tudor façade to the top half of the property, obviously some of these beams needed replacement.  Again in keeping with the originality of the property these replacements were custom made in Oak to the original sizes.  The fascia boards also were replaced where needed.  However one of the main focal points of the property was also in need of replacement, these being the large finials to the tops of both gable ends at the front.  Once removed it was soon realised that these weren’t to the original design as seen in the photos found.  Therefore new finials were custom made in Oak to match as closely as possible the design as seen in the photographs.

The external rendering of the building was also in poor condition in some areas, here the rendered panels were chopped off and replaced with products to match the original as close as possible. 

Another main feature of the building was that of the windows.  The original were of a wooden construction.  Here uPVC products were considered for fitting, but soon dismissed as not in keeping with the spirit of the building.  Therefore it was decided that new custom made windows would be used manufactured out of Sapelli.  The windows to the entirety of the property were to match the design of the windows to the front elevation.  However building regulations also needed to be taken into account through out the design process of the windows, this being that the windows had to open far enough for escape in the event of a fire.  26mm double glazed units are fitted to meet current energy efficiency ratings and also Georgian bars are incorporated into the top panels of the windows, again to mirror the heritage of the building.

The front and side elevations of the property are decorated to be a light colour and the woodwork again to be black at this present moment in time. 

Allow us now to consider the internal aspects of the project.  As stated previously the use of the property is to be changed from that of a public building into two private apartments and two offices.  Here at the beginning of the project, all the existing electrical systems were stripped out to make ready for four new electrical services, each to cater for the use of each sub-dwelling.  The existing plumbing system was also removed to make way for four new plumbing systems, consisting of mainly of hot and cold water feeds to all four sub-dwellings.  It needs to be mentioned at this stage that wiring is also incorporated to allow for remote key-fob locking on all external doors and also remote video entrance system for the apartments to the first floor.

The layout of the internals is greatly changed from that previously.  The most notable one being the re-positioning of the staircase to the first floor, so that the most space efficient layout could be used in both the apartments and offices below.  The walls between both the offices down stairs and also the apartments upstairs also had to be re-designed in accordance with the current fire regulations.  A fire break had to be incorporated in the roof between the two apartments, to stop the spread of fire through the roof void, but also the wall between the two offices had also to be designed with this in mind.  Stud walls to both floors are also installed to gain the desired layout shape of the property.  Once this was in place all external walls were re-plastered, stud walls boarded and skimmed, and the ceilings double boarded and skimmed also. 

Suspended ceilings are also to be installed in the office spaces

Both apartments are to incorporate new bathrooms, including floors being tiled and all walls being tiled from floor to ceiling, as well as kitchens being fitted to a modern design. 

The offices are to have suspended ceilings to gain a more professional feel to the spaces, storage space for all office essentials, male and female toilets, disable accessible toilet facilities, kitchen fitting in Grantham, all new computer cabling by Grantham Electrician

What you Need to Consider in your Search for a Chiminea

The tribesmen back in Mexico, during the 17th century, introduced to the world of fire pits and fire places a new structure that served the same purpose. Its characteristic long neck attached to the rounded bottom resembles a chimney and serves a similar purpose there as well. It is an outdoor fireplace that can also be used to grill skewers and cook meat. When not in use they are an ornamental addition to the garden or patio. These are normally made up of clay, aluminum and cast iron. You must know some facts about chimineas before deciding the kind of chiminea that would be apt for your backyard or other outdoor living space.

When it comes to choosing clay chimineas it sure does sound like a pretty good idea because that is how traditional chimineas used to be.  And when used for cooking it produces a lot of heat and its temperature raises high in a short span of time. The food cooked in these clay chimineas may have a different flavoring as well that comes in with the mixture of charcoal and clay particles. These clay chimineas can be either air-dried or kiln-dried. The air-dried version is generally the untreated version and may need some painting to be done to completely coat and seal it. The kiln-dried versions do not require any extra touch ups. The clay chimineas are weakly bound at the neck of the structure i.e. the junction between the end of the round bottom and the start of the neck-like structure so it is not advisable to carry the chimney at the neck.

Metal chimineas as compared to clay chimineas are way better with a lot of advantages over their clay counterparts. Metal chimineas are considerably stronger and more durable. They cannot be easily damaged or broken like the clay chimineas. They do not allow seepage of water into their bodies unlike clay chimineas and thus do not have the limitation of not being able to use in moist surroundings. They also conduct heat very efficiently. However, all the burning activity might give rise to rust on the metal body which needs to be maintained every now and then. Even then the rusty body gives it an antique look and it only enhances its presence as an attractive show piece.

Another thing to be considered is the size of the opening for the fuel inlet. It should be large enough to easily accommodate wood pieces of variable sizes. So it would be productive if you choose a chiminea with a larger bottom. You can also purchase a spark arrester which is a mesh like structure that can be used to cover the opening at the top of the chiminea or at the opening at the bottom. This would prevent sparks from escaping outside and damaging the surrounding. In all, it is a great addition to your backyard with all its uses and its heating properties.  Chimineas are a great addition to any outdoor living space.

Chimineas – Move Over Fire Pits, There’s A New Kid On The Block

Now that the weather is cooling down many homeowners are beginning to go inside earlier. However, if you love spending time on your patio or in your backyard in the evenings you don’t have to cut your time outdoors short. Instead, you can easily invest in outdoor heating for relatively little money.

There are a number of different outdoor heating pieces including fire pits, outdoor fireplaces, electric heaters, and heating lamps. Chimineas are another great option and they are often overlooked. When selecting which outdoor heating equipment is best for you, you should definitely look into chimineas.

Here are the key things you must know about selecting and caring for these unique outdoor heating accessories.

Clay Chimineas

Clay is a heat-resistant and durable material but it can still be prone to cracking if you do not properly tend to it. Clay chimineas should not be exposed to extreme temperature changes. They should also not be exposed to extreme freezing weather. In addition to this, clay must be kept dry so it is highly advised that you buy a waterproof cover if you invest in a clay chiminea.
If you are not familiar with clay chimineas then it is good to know that they change color after you use them a few times. This is called curing and it is a desirable and beautiful aspect about clay that many homeowners enjoy.
If your saleman does not tell you, then it is highly important to know that you must only start a small fire when you use your chiminea for the first time. You must also fill your chiminea with gravel, rocks, or sand to keep the fire from too directly touching the clay.

Less Exposure To Smoke
In addition to their beautiful quaint and rustic look, another thing that homeowners love about chimineas is their effective air flow systems. Some homeowners buy propane fire pits, fire tables, and other clean burning outdoor heating accessories to avoid problems with smoke and fumes. However, chimineas are specifically designed to send smoke away from you and your guests. They are open on one side and have chimney structures on the top.

Metal Chimineas
Some people consider metal chimineas to be an overall better choice than clay chimineas, but metal is also prone to crack, rust, or warp depending on the kind you choose. Some top choices include cast aluminum (not sheet aluminum) and copper. Another popular choice is cast iron–you just have to beware that cast iron stains surfaces. And of all the metals you can choose from, it is best to avoid sheet metal–it is considered a disposable metal and does not last very long.

Much like fire pits, chimineas are prized for being great patio and backyard accessories. They add a design element to landscapes and function as a great source of heat. As a last note, keep in mind that the larger and thicker the chiminea structure, the more durable it will be.

Product Description
New Clay Crucible. This is a new clay crucible. For centrifugal casting machines. The crucible has a slot to fit Pro-craft casting machines. Made of fused silica with a clay bond which will last through many meltings. Great for metal melting up to 2,500 F (1,371 C). Has a 12 oz capacity.

Centrifugal Casting Crucible 250dwt fits Pro-Craft

Precious metal clay (brand names are PMC and Art Clay) is modern-day alchemy. PMC is a clay base with tiny pieces of silver suspended within it that, when heated, burns off the clay leaving a solid silver residue. The clay base acts as a binder for the metal particles. Once this has been removed, the remaining silver particles bind together, giving you the finished product.

The real beauty of precious metal clay is that it can be manipulated like any ordinary modelling clay, making it perfect for jewellery making. The modern precious metal clay can be using a jeweller’s torch, as the firing temperature is much lower than the early versions of this clay. However, a small kiln will produce a much more constant temperature range and can be controlled exactly, meaning that the results will be more consistent.

Precious Metal Clay once had a very bad reputation for shrinkage, making it unsuitable for fine work or detail. Modern precious metal clays have a much lower shrinkage rate (around 10-15%), but you still need to factor this into the final piece to ensure that really fine detail is not lost in the firing process.

Once fired, the silver piece will seem very lacklustre and dull, so it will need finishing. The dull matt surface hides the real beauty underneath, so finishing and polishing will reveal the shining silver below. When soldering finished precious metal clay pieces it is essential to remember that the surface will be more porous than standard sterling silver, so it is best to burnish the piece prior to soldering. But because it is almost pure silver there is little risk of fire stain on the surface and the final results are almost indistinguishable from sterling silver.

Because precious metal clay is a clay, it takes impressions very well. A design can be pressed onto the surface of the clay and be revealed in the final silver piece. Patterned rollers, lace or even leaves can be used to create unique effects that are difficult to reproduce in ordinary silver unless it has been cast. Precious metal clay is a popular way of making silver beads. The clay can be formed into beads, decorated with a surface pattern and then fired in a kiln quickly and easily, producing high quality silver beads.

Safety considerations have to be taken into account when working with precious metal clay because of the high temperatures required to fire the clay. A small enamelling kiln allows you to safely achieve the temperatures required for optimum results, but ensure that you have all the correct equipment such as tongs with heat resistant handles to extract work from the kiln safely and a heat-proof surface upon which to work.

Precious metal clay is an ideal medium to work in if you want to create pieces of silver jewellery that are unique to you. The only thing that limits you is your imagination. Precious metal silver clay is widely available from good jewellery equipment suppliers. There are two main brands – Precious Metal Clay and Art Clay Silver. The clay is also available in other metals including gold, but the cost is significantly higher than the silver clay.

Metal clay is a suspension of tiny particles of metal in a clay binder, which can be used to make jewellery, beads and small findings. The beauty of metal clay is that it can be manipulated in the same way as any modelling clay, but once fired the binding agents are burnt off leaving the metal form intact. Although there is a certain amount of shrinkage (between 10-15% for the more modern versions), very fine detail can be achieved, including impressions that would require casting in any other method of metalwork.

Silver metal clay results in objects containing almost pure silver (also known as fine silver) which is ideal for enamelling. There are two popular brands available – Precious Metal Clay (also known as PMC) and Art Clay Silver (ACS). Precious Metal Clay was developed in the early 1990′s in Japan and consists of microscopic particles of pure silver (or fine gold powder) and a water-soluble binder which burns off during firing. The original formula of PMC (now called ‘Standard’) has to be fired in a kiln at a temperature of 1650F and has a high shrinkage rate of around 30%. Two additional versions were later developed called PMC+, which can be fired at 1490F and PMC3, which can be fired at temperatures as low as 1100F. Both of these later versions of PMC have much lower shrinkage rates, allowing much finer detail to be worked into designs.

Art Clay Silver (ACS) was also developed in Japan and is similar in consistency to PMC+. The main difference with ACS is that it can be fired using a hand-held torch or gas oven. Because of subtle differences in the binder components and the longer firing times, ACS benefited from having a considerably lower shrinkage percentage – only 8-10%. This means that ACS can be worked in more detail without any loss of definition in fine work. Art Clay Slow Dry was introduced soon after, which has a much longer working time before requiring firing, allowing intricate work to be moulded into the clay with no loss of malleability.

Art Clay 650 and Art Clay 650 Slow Dry are now becoming increasingly popular, as not only do they have a longer working time but can be fired at temperatures as low as 650C/1200F. This allows jewellers to incorporate glass and Sterling Silver into the designs without fear of damaging the components. AIDA, the manufacturers of ACS have also introduced Oil Paste, a product only used on fired metal clay or milled fine silver, and Overlay Paste which is designed for drawing designs onto glass and porcelain. These two products have allowed the use of metal clay products to be incorporated into a whole new range of designs and mediums, expanding the potential of this product.

Metal clays allow jewellers to work with a material that is as malleable as ordinary modelling clay but produces fine (almost pure) silver jewellery of exquisite intricacy and beauty. Once polished it has a lustre and shine that is easily comparable to cast silver and because of the development of the products over the last few years shrinkage is now no longer an issue. The type used depends on personal preference as both types have their advantages, but incorporating metal clays into your jewellery design gives you a new medium to explore with beautiful results.