Frequently Asked Questions

Investment casting is an industrial process based on and also called lost-wax casting, one of the oldest known metal-forming techniques.[1] From 5,000 years ago, when beeswax formed the pattern, to today´s high-technology waxes, refractory materials and specialist alloys, the castings allow the production of components with accuracy, repeatability, versatility and integrity in a variety of metals and high-performance alloys. Lost foam casting is a modern form of investment casting that eliminates certain steps in the process.

The process is generally used for small castings, but has been used to produce complete aircraft door frames, steel castings of up to 300 kg (660 lbs) and aluminium castings of up to 30 kg (66 lbs). It is generally more expensive per unit than die casting or sand casting, but has lower equipment costs. It can produce complicated shapes that would be difficult or impossible with die casting, yet like that process, it requires little surface finishing and only minor machining.

We typically quote a tolerance of +/- .005 per inch with a surface finish of 125 RMS or better.

An Investment Casting offers:

• Design Freedom
• Near net shape
• Fine detail
• Excellent mechanical properties

• Stainless Steels
  • Chromium-Nickel Stainless Steel
  • Heat Treatable Chromium Stainless Steel
  • Precipitation Hardening Stainless Steel Alloys
  • Heat and Corrosion Resistant Stainless Steel Alloys
• Carbon and Low Alloy Steels
• Tool Steels
• Copper
• Copper Alloys

We do cast some specialty and other alloys upon request.

At Thompson Investment Casting our size capability ranges from a fraction of an ounce up to about 25 lbs actual casting weight. The actual size limitation would be approximately 18 inches in length or width. Wall thickness can be achieved as thin as .020 using our specialized vacuum assist process.

• Investment Casting offers low tooling costs compared to other processes
• Investment Casting has the ability to achieve near net shapes in the casting
• Investment Casting can achieve close tolerances
• Investment Castings have a smoother surface finish as compared other casting
• Investment Casting offers many alloy options

• Sand Casting
  • Investment Casting has improved surface finish, more precise, tighter tolerances, greater design capability and greater alloy choices.
• Forging
  • Investment Casting allows for greater design freedom equating to more complex geometries.
• MIM
  • Investment Casting has lower tooling costs, is capable of producing larger parts, has lower alloy costs and can economically produce smaller run quantities.
• Machining
  • Investment Casting offers material and labor savings for each required part

Samples-----------2 weeks
Production--------4-6 weeks

Please contact us for a detailed quotation.

A Rapid Prototype process can be implemented which will be a low risk opportunity to prove your design using Investment Casting. This will provide you and your company an Investment Casting for your testing and evaluation. Often a cast prototype can be produced in 2 weeks.

Yes we can provide

• Machining
• Heat Treatment
• Metal Finishing
• Testing
• Certifications