First time investment mold maker

[carbidecraters]

Ok so we have a competent cnc machine shop but have never made a investment mold. I know we have to take in account shrinking and venting but what else do we need to understand? I have a investment casting house ready for tooling but I dont want to come across like a complete ass. This is a rookies attempt at a investment mold. We are lookign at 356 aluminum and using a basic 6061 mold for the wax

[carbidecraters]

My questions is can we make the mold halfs and then ask for suggestions or this their a good website for more info so we can have a better chance of success?

[Geof]

Did you do any Googling? Here is one link for background info http://www.wtec.org/loyola/rp/10_01.htm

Why don't you go to the casting house and ask them what is needed. You probably do not consider they are asses because they do not know how to run a CNC machine; why should they think you are an ass because you do not know anything about lost wax casting?

[carbidecraters]

I think we will make a basic mold and bring it to them for analysis.

[Leehound]

Originally Posted by carbidecraters We are lookign at 356 aluminum and using a basic 6061 mold for the wax

I have been building Investment Casting molds day in and day out for the last 18 years. All the foundrys that I have worked with would "not" like your choice of 6061. The accepted grade of aluminum is 7075-T6.

What else do you need to know?

Scott
SJC Tool & Engineering, Inc.