cast Alloy Features
Using traditional casting techniques and modern metallurgy we have developed a very special alloy casting to enhance the look and feel of the original. Our cast alloy is slightly lighter than iron, making it easier to install but heavy enough to give the solid metal ‘knock’ when the tub is touched. It will not rust, it’s extremely strong and has wonderful thermal properties. We are exceptionally pleased with how they have turned out, for clients that want the luxury, look & feel of the original without the cost of an antique. The Alloy tubs weigh around 185-225lbs compared to the original iron which weighs around 275-325lbs. We just think that modern understanding of metals allows us to use a superior product (albeit costlier to produce) than iron. Side by side with an original cast iron they are almost identical, it does not feel or sound like acrylic. It feels, looks and sounds like an old iron tub.
Whilst our castings were originally from France and England, in 2011 we started working with 3rd and 4th generation (100+ yr old) family owned/operated foundries here in the US. Being such old and time honored businesses they understand the techniques and craftsmanship that goes into sand casting such opulent shapes. They use the same hand cast, ‘green’ sand molding processes in keeping with our vintage ethos. With the aid of an original Antique European tub we use a time honored casting technique called ‘sand casting’. By creating a mold of the tub in sand we are able to re-cast using a recycled (and fully recycle-able) Alloy metal. This process also keeps all the intricate details of the original tubs plinth, whereas mass production molds smooth out and eliminate those classic details in the name of cheap production.We re-cast every tub to order so that each clients tub is truly theirs. No mass production and no rows of tubs waiting to be purchased.
The interior is given its final sand before being chemically cleaned and converted. The exterior is masked using special high temperature tapes which can withstand the baking temperatures the casting needs to be outgassed and annealed in preparation for the initial Ground Coat. It’s taken around 2 weeks to get from raw casting arriving at our workshop to prepared tub.
Once ordered a clients name is put on the casting list and our workshop waits. The raw castings arrive from the foundry looking a little rough around the edges. Due to the nature of sand casting the castings are very textured and need extensive work to prepare them for finishing. Unlike production mold and mass produced tubs our items require many hours of prep before they can be enameled or polished. To begin, the exterior is ground or fettled to remove the sand texture and to begin the smoothing process.
The exterior of each casting is ground/fettled and sanded from 80G through almost every grit until 1200 Grit. Around 6-8 days buts its worth every hour to get the exterior ready to be mirror polished. Once the interior surface is masked and protected we can begin the ‘polishing’ phase. Using a hand polisher at a relatively slow speed we ‘cut’ the tub using a very aggressive compound which actually dulls the surface but removes any fine scratches and sanding marks. Each pass from top to bottom creates an even finish which can be ‘moved’ around the tub in a single band. Once the initial compound is completed, we switch polishing pads to a less aggressive pad and to a rouge based compound. The whole tub is buffed to bring out the start of a high shine. This pad creates the Satin polish which is very reflective and many companies call this ‘Polished or Burnished’ but we’ve only just begun.
After around 2 days of work the tubs surface is now ground smooth and we can being sanding. We sand from an 80 Grit to 1200 Grit, using progressively finer sanding discs until the tubs surface is extremely smooth and begins to show some reflection. At around day 6-8 the Exterior is prepared and the Interior work can begin. The interior also needs to be ground and fettled into shape using a more aggressive grit than we use on the exterior. It is then aggressively sanded to create the perfect key for the ground coat. Before we can apply the initial coatings we hand apply a very special high temperature liquidized alloy powder to smooth and fill any minor pitting in the casting.
Now Buffed we can change to a true polishing pad and a fine chromium polish. The tub has to be polished in a uniform manner keeping the pad at a constant angle moving slowly to ‘move’ the shine around the tub. Next, yes we may be several hours in but we are close, the final ultra polishing pad and jewelers rouge. This is the rouge used to make fine jewelry shine! The tub is ultra gloss polished using the same uniform technique to create a true mirror polish that looks like chrome or nickel. With a quick hand buff to remove any polish residue the exterior is now completed. Our new Cast Alloys do NOT rust, they are non-ferrous castings which means it will never rust. Once polished a naturally occurring microscopic oxide forms which is clear and virtually impenetrable. It is stable and can be easily cleaned and live in a humid, wet bathroom without fear of the tub looking like a rusty old tub. We want to point out this is not a coating or applied finish. We offer our Hand Polishing services as ‘desired’ final finish, each bathtub will be truly unique and subtle characteristics (pitting, graining etc.) in the finished surface are not considered flaws but the characteristics of a true metal polish.
Alloy Casting vs. Cast Iron Casting Facts & Specifications
Strength: In the past, Alloy largely appeared in the form of sand castings and since the material cost was high, alloy/aluminums of a cheaper grade were often used. It is some of these cheaper cast aluminums that have given this material an undeserved reputation. Modern Alloy castings have extreme dimensional stability; that is, they do not warp or crack. Incorrect aluminums used in casting, or incorrect procedures, can cause cracks to form in the initial part; however, these are readily observable and occur during the casting process. The Alloy Castings have been made and sold for over a decade without problems. The in plant failure of components due to cracking is considerably lower than with cast iron. In general, an Alloy component can be dropped on a concrete floor without serious damage due to Alloy ductility. This is not the case with cast iron due to cast irons brittleness. Corrosion Resistance: Question: Does Alloy corrode? Answer: Technically yes. It corrodes different than most materials - on exposure to oxygen an oxide forms almost immediately. However, this Oxides form a strong corrosion resistant coating, but with the ferrous components of cast iron and steel, it does not rust. Question: Does oxidation continue and destroy the material? Answer: No. The Alloy oxide formed on the exposure to air is a corrosion resistant oxide and under normal conditions, oxidation stops or it takes place very, very slowly. The oxidation will turn the Alloy a slight grayish color (this coating will have occurred long before the tub is delivered). In the absence of abrasion and in normal atmospheres, this oxide forms a very efficient protective coat. In fact, anodizing of Alloy is merely a method of rapidly producing an Alloy oxide of greater than normal thickness and hardness, and is used where extreme protection is necessary. In the case of cast iron, an oxide forms which continues to change its chemical composition from Fe0 to Fe2O3, to Fe3O4, and the rust continues - eventually through the iron. This is not true of Alloy. Steel forms these oxides very rapidly and eventual failure of an unprotected steel component in a normal atmosphere would be much more rapid than cast iron or Alloy. In fact, iron and steel are never used in the unprotected state. Alloy is usually used unprotected. For example - piping, structural members, building siding, food containers, windows, doors, fences, gutters, etc. Question: This is all right for an average atmosphere, but how about unusual conditions? Answer: One of the conditions most usually brought up is that of exposure to sea air and water. Alloy has a much greater resistance to corrosion than does iron or steel. A steel ship must be protected from the salt water or the corrosion of the steel is destructively rapid. Many ships are built of Alloy and, while they are painted for protection primarily against the growth of marine life, they are, on the whole, more resistant than steel to the action of salt water. Currently many large ships and tankers are built of Alloy. The Coast Guard is replacing its steel buoys with Alloy buoys. Question: Why do some people still believe Alloy corrodes more than iron or steel? Answer: Prejudice and/or lack of accurate information. The following is from "Kent’s Handbook" on the "Corrosion of Iron Alloys", and under "The Mechanism of Corrosion". "SURFACE FILMS - Clean metallic surfaces exposed to air quickly acquire a film of oxide, which, at ordinary temperature, is thin and invisible. At higher temperatures it is thick enough to give well known characteristic colors - rust. The nature and properties of the film depend upon the composition of the metal itself and its environment. Alloy and stainless steel, for instance, owe their high durability to the formation of a continuous and permanent file that is stable under most conditions of exposure". In general terms, Alloy is more resistant to corrosion by most common materials and atmospheres than cast iron, and far more resistant to corrosion than is carbon steel. Question: How does paint/clear coat affect corrosion? Answer: All iron and steel must be painted immediately in order to prevent serious atmospheric and other corrosion from taking place. While Alloy is far more resistant than iron, it generally is painted, and when used in combination, all three - the Alloy, the iron, and the steel, are always painted. Here again, Alloy shows one very great advantage. The Alloy oxide which forms on the surface of the Alloy is a relatively impervious surface preventing additional oxygen from contacting the Alloy. This surface is hard and tenacious, so when a coat of paint is placed over it, there is little tendency for the oxide to leave the surface. This is the reason that paint has such a far superior clinging action to Alloy than to iron or steel. If iron or steel has any traces of rust under the paint/clear coat, the oxide in the rust continues to attack the metal and form additional oxides which flake off, taking the paint with them, and exposing the base metal to the atmosphere. Where extremely corrosive conditions do exist, Alloy can be easily protected. A clear coat will provide excellent protection. an almost indestructible finish. Such treatments are costly but are available if the conditions warrant.