Coatings for Sand Molds and Cores

Coatings for Sand Molds and Cores

Foseco’s sand mold and core coating products help foundry operators achieve the best available casting surface finishes at the highest possible level of operational efficiency. Because we focus our efforts on advanced rheology and suspension technologies, and use only the highest quality refractory components, Foseco’s sand coating products provide “as-cast” excellent surface performance, particularly in critical applications. They are also noted in the industry for their ease of use and process productivity.


Foseco’s Sand Coating products provide:
• Reduced defects, particularly sand burn-in.
• Increased productivity, because Foseco’s pioneering work in coating rheology and suspension technologies allows full-rate production of castings, minimizing coated   core scrap and rectification, coating process variation and handling slow-downs.
• Improved quality, in addition to reducing defects, by acting as a robust element in a consistent foundry process


Refractory coatings provide a protective barrier between the molten metal and the mold or core substrate. This barrier is of paramount importance in ensuring the integrity of the as-cast surface of the finished component.  Inconsistencies within the coating structure or the application method will be reflected in the surface quality of the component.


The improvement in as-cast surface finish can be as basic as the removal of sand grain definition, but more often it is the reduction and elimination of a number of casting defects:
• Metal Penetration
• Poor Casting Strip
• Mold Erosion
• Metal / Mold Reactions


By careful selection of refractory fillers and rheology, Foseco coatings are designed to deposit the correct coating structure onto a given substrate, to ensure cast surface integrity and the application characteristics required by the foundry. The range of products have been specifically engineered so that they can be applied by dipping, flow coating, brushing, swabbing and spraying.


Aluminum Foundry

It is frequently possible to produce good surface finish on highly cored aluminum castings prepared in sand moulds without the need for a refractory coating. Nevertheless, problems can occur and Foseco supplies a range of products to address these.


Copper Foundry

Refractory combinations are chosen to provide optimum protection for specific casting conditions, while maintaining a cost effective solution. The section thickness of the casting is a good measure of the casting conditions that will prevail and the type of casting defects which the coating must overcome. By ensuring the correct refractory combination, complemented by optimised application rheology, casting defects are minimised and surface integrity is ensured.


HOLCOTE water based coatings

HOLCOTE products are water based coatings with a full range of application rheologies and refractory combinations that offer superior performance for individual foundry requirements. Applicable to both sand molds and cores and generally oven dried.


ISOMOL solvent based coatings

ISOLMOL products are solvent based coatings with a full range of application rheologies and refractory combinations that offer superior performance for individual foundry requirements. Applicable to both sand molds and cores and generally air or flash dried.

"Prior to our relationship with Weaver Materiel, we were purchasing riser sleeves direct from the OEM. As a stocking distributor, Weaver typically is able to deliver same or next day. OEM lead times averaged three to four weeks. With Weaver, I've been able to reduce my working inventory by about 40%."

- JD Schmidt, QA Manager, Ohio Ferrous Foundry

“Ashland Foundry & Machine Works and Weatherly Casting are grateful for the partnership in our working relationship with Weaver Materials.  Weaver has helped us maintain pricing and avoid increases in a volatile market.  Weaver has always kept us in supply of material when markets dictated shortages/allocation status.  If Weaver was not in our vendor pool daily production ability would have been negatively impacted.  Weaver is also technically able to review our foundry processes and make suggestions to either achieve a cost savings or process improvement.  I am looking forward to a continued collaboration between the Weaver team and my locations.”
- Chrissy C