hot & cold CAST BRONZE EXPLAINED

There are a number of differences in the process of creating cold cast and hot cast bronze sculptures. In the example below, the Dodo on the left is cold cast bronze, while the Dodo on the right is hot cast bronze.

HOT CAST BRONZE

This more expensive method involves an ancient process which dates back many thousands of years. It involves producing a hollow wax image of the sculpture which is then coated in a thick ceramic layer which is allowed to dry thoroughly.

The wax is burned away leaving a ceramic shell into which molten bronze is poured. Once cooled, the shell is smashed away to reveal the casting which is then cleaned and patinated by heating the bronze with a blow torch and applying a variety of chemicals. This is then left to cool and wax polished.

Hot cast sculptures can last many thousands of years whether indoors or outside in the elements.

Please note that due to the difference in the casting process, the Hot Cast Bronze sculptures are approximately 3% smaller in size to their Cold Cast counterparts.

COLD CAST BRONZE

Also referred to as bronze resin, this technique involves blending bronze powder with polyester resin to produce a material which is applied to the interior of the silicone mould. Subsequent applications of this will produce a shell into which an armature (wire frame) can be constructed. It is then rubbed back to reveal the surface and this can then be patinated (coloured) using a variety of chemicals, waxes and stains.

Cold Cast Bronze Resin sculptures can last a long time if looked after.  These works are frost proof but NOT shatter proof.  In extreme weather conditions they are susceptible to the effects of expansion and contraction which can cause damage.

If breakages occur, these can remediated at cost. Simply get in touch with us and we will provide a quote.

CERTIFICATE OF AUTHENTICITY

Our hot cast sculptures are accompanied by a certificate, verifying the authenticity of the sculpture's limited edition status and edition number.

MORE INFORMATION

Refurbishing a Bronze Sculpture

Because of the unique natural properties of bronze—its high copper content and its irrepressible want to oxide over time—eventually, the ‘living’ surface of your sculpture will transform into a beautiful rich shade of verdigris. 

Despite this unavoidable yet stunning evolution of your bronze garden sculpture, it is possible to not only slow down the natural process, but, in essence, reverse it. 

Below is our video showcasing the technique used, or use the button below to read our full guide.

How to Refurbish Your Bronze Sculpture

What you need to know

SLATE PLINTHS & STANDS

All cold cast sculptures are provided with a slate display base, please contact us for information on hot cast bases. 

Hot cast sculptures can be provided either with a slate base or a metal ‘I’ beam for concreting into outside ground to increase security.

In addition, we are able to recommend a number of alternatives for displaying your sculptures, including cold cast or stone plinths and hardwood stands. If you have a particular idea in mind for displaying your sculptures, please get in touch with James to discuss the options.

WARRANTY INFORMATION

Robert James Workshop Ltd offers a ten year warranty on Hot Cast Bronze sculptures and one year warranty on Cold Cast Bronze Resin sculptures. This warranty applies to defects in the manufacturing process only and not as a result of misuse or accidental damage.

Water Features are also subject to a one year guarantee and in addition, we offer a maintenance service for the working parts. Please contact James for a quotation.

TERMS & CONDITIONS

Hot Cast Bronze and Cold Cast Bronze Resin sculptures are given a patina which is intended to last a long time. The surface colour of the sculpture will change however and eventually turn a verdigris colour due to the high copper content of the piece. Oxidization of bronze naturally turns green. The surface is a `living surface’ which changes and is the natural beauty of bronze. However, such changes can be delayed up to a point by applying wax which provides some protection

Cold Cast Bronze Resin castings will ‘weather’ like bronze in that they will patina a verdigris finish if left alone. To retain their radiance we recommend a neutral wax coating at least twice a year. The highly polished areas can be restored by using a metal polish and a buff up.

The environment your bronze is placed in will also affect the surface quality. Salty air, bird excrement, plants and trees which produce certain saps, all these substances can change the look of the bronze.

Cold Cast Bronze Resin sculptures are not as robust as Hot Cast Bronze so please be aware of this when handling them. Always choose a solid part of the sculpture when lifting, avoiding the thinner and more vulnerable areas such as arms or other protruding parts.

Our Hot Cast Bronze and Cold Cast Bronze Resin water features require particular care when it comes to the winter months. It is imperative that water features are drained off to protect them during frosty conditions. Water that is left in pipes and then freezes will result in the pipes expanding and bursting. 

Placement is also important when choosing a location and in particular, keep your sculptures away from large trees that may drop branches.

Due to increasing climate change patterns we advise the following precautions are considered.

Cold castings are more vulnerable to the affects of hot and cold weather conditions.

The surfaces can expand and contract sometimes causing fissures to occur. These changes are not subject to the guarantee agreement post the 12 month period as local environmental effects cannot be accounted for. To reduce the chances of adverse affects we recommend that the sculpture is bubble wrapped and waterproofed for the colder months of the year. For hotter climates we advise shaded positions and if extreme heat is experienced removing them from direct sunlight.

If your budget allows we always recommend Hot Cast Bronze purchase options as they are unrivalled in their durability and longevity.

As part of the process of sitting your water feature and connecting the pump to the mains supply, please ensure that the cable is protected and is connected to a ground Fault Interrupter, for your own protection and to comply with safety regulations. Robert James Workshop Ltd can take no responsibility in the undertaking of the above and would advise that a qualified electrician is used. 

If you have any questions please don’t hesitate to ask us for advice on where to place your sculpture and any other care recommendations.

**As part of the process of sitting your water feature and connecting the pump to the mains supply , please ensure that the cable is protected and is connected to a ground Fault Interrupter , for your own protection and to comply with safety regulations. Robert James Workshop Ltd can take no responsibility for electrical connections nor the fitting of electrical appliances.**

FREQUENTLY ASKED QUESTIONS

How much do you charge for shipping overseas?

Due to the myriad of factors regarding overseas orders, we provide all the necessary details and costs on a 'per order' basis. If you live outside the United Kingdom and wish to purchase one of our sculptures, please get in touch with us to discuss the options.

Why is hot cast bronze so much more expensive than cold cast bronze?

There are a number of differences in the process of creating hot cast and cold cast bronze sculptures. A full explanation of these differences may be found further up on this page, or by clicking HERE.

What precautions are required for the winter months?

Our bronze water features require particular care when it comes to the winter months.

It is imperative that water features are drained-off to protect them during frosty conditions. Water that is left in the pipes and then freezes will result in the pipes expanding and bursting. This, in turn, may result with the castings failing.