Investment Castings


When I first learned about investment casting I asked what does it have to do with investing?  Someone made a joke about the investment in tooling, another person thought it had something to do with having to make new patterns every time you wanted to make a mold.  While the first person was right that the cost of tooling is higher than for sand casting, the second person was a bit closer to the truth.  It turns out people used to say invested when referring to putting on clothing or when surrounding something.  In our case for investment casting, the investment refers to the ceramic shell that surrounds the wax or foam pattern.

A challenge I had was when foundries would ask whether I wanted castings made from the silica sol or water glass process.  What is the difference?  Without getting into detailed chemistry or material properties, silica sol (SiO2) molds will produce castings with a finer surface finish and better dimensional tolerances, roughly ±.005” per 1” of linear dimension, versus double that for water glass (sodium silicate).  The difference in price between the two processes is about 20%, but where machining is required some of those savings end up being used to remove more material. 

How the investment casting process works:

The lost-wax investment casting process starts with an aluminum mold which will create the wax patterns, each of which will produce a single finished casting.

Those patterns will be added to trees which will then be coated with the ceramic slurry.  The number of coats will depend on the alloy being poured and how strong the wall should be to hold the metal.

After cooling, the investment castings are removed from the ceramic shell, detached from the trees and the metal is recycled.

The chemical composition of raw material is retained on file, and any testing of raw castings, such as dye penetrant testing is performed.

After machining and quality control, the castings are ready for packing and dispatch.

The capability of consistently holding better ISO 8062 casting tolerances, much smoother surface finish, and comparable ease of casting complex geometry are the main reasons investment casting is chosen over sand casting.  For alloys that are more expensive and difficult to machine, like stainless steel, the reduction in material and machining costs outweigh the higher processing times and costs.  If you need any help determining the lowest total cost of ownership for your metal component parts, please reach out to us for a consultation and quote!

Brukar Inc. at The Canadian ASQ Conference 2017


I was very excited to attend the first ever ASQ National Conference held in Canada, on September 25th and 26th in Ottawa, and to kick off the event distributing some post cards supporting social responsibility – all along I was thinking about the focus/theme of the conference;

”A Confederation of Quality Professionals Working Toward an Inclusive and Sustainable Canada”

and how we can work together to make a stronger and more resilient Canada.

Just the theme itself gave me a sense of unity and cumulative sustenance. The word sustainability though, sort of stood out for me.  It led me to think “what is the relationship between quality and sustainability?” Does quality quantify sustainability or does sustainability measure quality? I concluded that the two are interlinked – HAPPY THAT THEY ARE INSEPERABLE.

Brukar Inc., has for over 32 sustainable years, provided steadfast quality parts and services to customers all over the world, starting right about the same time that Dr. Deming and Dr. Juran encouraged quality principles that sounded ahead of their time. Accordingly, the commitment to quality formed the foundation of Brukar’s business eminency, and sustainability defined its future.

The marketplace and technology are ever evolving. Brukar not only withstood, but in fact embraced the changes. By staying focused on creating value propositions, being part of the business ecosystem, and collaboratively sharing vision with employees, customers and suppliers, Brukar creates great value that benefits all stakeholders.

This brings me back to the essence of the conference… Canada can flourish with today’s go-to-market competitiveness, and embrace change by forging ahead with a content-oriented and integrated approach in which the aspect of collaborative effort is vital, taking diverse ideas to the next level, and benchmarking with the world’s leading businesses, and by adopting the principals of sustainable quality that defines successful businesses.

The conference featured highly esteemed “thought-leaders”, who addressed a variety of topics. Each shared their profound knowledge that involved expansive views and diverse ideas, their topics encouraged cooperation, all geared toward creating and maintaining a high performing Canada.

I am looking forward to attending more ASQ Canada Conferences, as I thoroughly enjoyed this first conference in Ottawa…