Questions and Answers
1. What is a “lost wax” “investment casting”? What advantages do I have switching to this method?
The goal is to supply near net shape parts often requiring little or no further machining or minimal operations. This process offers cost savings, design improvement, broad alloy selection including material interchangeability, close tolerances, and weight reduction. Once the initial tool is made you can start producing consistent parts order after order.
2. What alloys do we pour?
Value add services include machining, precision grinding, assembling, spray coating, plating, painting etc. Occasionally we are asked to support custom alloy requirements for our customers.
3. What size range of parts can be produced by our process?
4. What “as cast” dimensional tolerances I can expect?Your Title Goes Here
The Investment casting institute publishes a standard generally accepted and adopted by Investment casting operations across the globe. This varies depending on the size and complexity of the part. In addition straightening or specialty foundry operations may be used to improve tolerances on critical dimensions. We recommend that every part and its application be discussed and designed with input from our technical people.
Premium tolerances should be applied only to those “as cast” features which are considered critical relating to function and reliability or where a feature cannot be machined.
Examples of our tolerances include:
A. Linear Tolerances.
Up to 1/2″ +-.007″
up to 1″ +-.010″
every inch after add another +- .005″
B. Minimum Wall Thickness.
Alloy Small Area Normal
300 Series SS ..080”
Cobalt Alloys ..080”
400 Series SS .080″
Carbon Steels .080″
C. Angles.
As cast tolerances of angles depends on their location in casing. They range from +- ½ deg. Design tolerance may be as large as 2 degrees (or more) where a large distortion could be expected.
For a more comprehensive list of tolerances see design data.
5. What type of surface finish can I expect from an investment casting?
Casting Surface Finish.
RMS Range 60-170 (depending on material)
Standard RMS 125
6. How to get the best value from Investment castings
7. How many pieces do I need to order to make precision investment castings the right solution?
8. What is the most efficient way to quote an investment casting?
The best way to quote a new investment cast part is to establish direct communication with one of our team members. Discuss your needs and supply as much information as possible including a drawing (and sample if possible). If you can, provide an actual weight, material specs, condition required (kind of heat treatment, NDT, any special requirements such as surface quality, etc.). Also indentify critical dimensions or surfaces and service of the part. Our technical team may offer suggested design changes or considerations when mutual benefit may be realized.
9. What type of tooling is necessary to make a wax pattern?
With today’s technology on low volume, one offs, rapid prototype wax patterns can be produced avoiding hard tooling costs. For any type of future or repeat production needs we strongly encourage the development of hard tooling right from the start. Usually, a split cavity aluminum die is manufactured which is a negative of the final part increased by a shrink factor of the wax and steel. Depending on the complexity of the casting, various combinations of the aluminum, ceramic or soluble cores may be employed to produce a desired configuration. Most tooling price range is within $1,500 – $10,000. Very complicated tooling or high production automated tools can exceed this price range. This tooling is a customer’s property.
10. What about casting integrity?
11. What lead times can I expect when ordering an investment casting?
12. When Should I Contact Precise Castings?
Make the Investment Caster an important part of your product design team. No one will know your product better than you but we can certainly identify areas of concern if your intention is cost, material and time savings in the casting process. Our knowledge of the metal processing industry will enable you to choose the right steps to produce your parts in the fastest, most cost effective manner.
Often, simple, non-functional design changes can be incorporated which will drastically reduce tooling costs.
One of the most attractive aspects of the investment casting process is the versatility of design. The casting buyer should take full advantage of the expertise offered by the foundry’s engineers. This will not only ensure the lowest possible product cost, but will help to prevent costly delays due to re-engineering.