Investment Casting: Everything You Were Afraid to Ask or Didn't Know

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • CollectiveBorg
    Lieutenant, Junior Grade
    • Dec 2025
    • 20

    #1

    Investment Casting: Everything You Were Afraid to Ask or Didn't Know

    Hello everyone.

    At the request of forum members, I will try to explain, in full detail, how to master investment casting.

    I will describe the complete process from start to finish, including all necessary consumables, tools, equipment, as well as examples of how to replace purchased items with homemade alternatives to save money.

    So, let's begin.

    A little about myself. My name is Anton, and I have been working as a jeweler in a private jewelry workshop for the past five years. I have never completed any formal courses related to this profession.

    The only profession I have that is officially confirmed by a state-issued diploma is that of a career military officer.

    Everything I know and everything I do, I learned from publicly available sources.

    I will explain the entire process with a focus on scale modeling rather than jewelry making, so it will be easier for you to understand. However, everything described here works just as well in the opposite direction.

    ATTENTION!

    This material will be very extensive. To ensure that the entire guide remains available in full and in the correct order, I strongly ask everyone not to comment on this topic until I write in the final post that I have shared all of my experience and that questions are welcome.

    If someone decides to begin working on their own before I finish writing this guide and needs my advice, you can always send me a private message.

    Later, this topic may evolve into a question-and-answer discussion, but I would like the first page and the complete guide to remain intact and uninterrupted.

    So, let's begin.

    What is investment casting?

    Investment casting is a process in which a disposable wax model is destroyed during the burnout of the mold, and the resulting cavity is then filled with molten metal during casting.

    Here is the complete sequence of operations required to produce a metal casting using the vacuum casting method:

    (Each of these steps will be explained by me in detail, with examples, different implementation options, pictures, and videos, exactly as I perform them in my day-to-day work.)
    1. A wax model is made.
    2. If only one model is being cast, it is attached to a sprue, which is then attached to the flask base.
      2a. If multiple models are to be cast at the same time, a "tree" is assembled. This consists of a thicker wax rod serving as the "trunk," onto which the models are attached using a wax pen. Each model is connected to the trunk through its own sprue.
    3. A perforated flask is placed onto the flask base. The flask is usually wrapped with either masking tape or regular tape beforehand. I use regular tape because it is more reliable.
    4. The investment material is prepared and poured into the flask using a vacuum.
    5. After the investment hardens, the rubber flask base is removed, the tape is taken off, and the investment is trimmed with a knife to remove any excess material that has flowed onto the flask.
    6. The flask is placed into a burnout furnace equipped with a controller that allows temperature stages and their durations to be programmed.
    7. After the burnout cycle is complete, the furnace program transitions to a holding temperature suitable for casting molten metal into the flask.
    8. The flask is removed from the burnout furnace and filled with molten metal using either vacuum casting or centrifugal casting.
    9. After cooling, the investment material is broken away using water or mechanical methods, and the casting is removed.
    10. The castings are separated from the sprues, cleaned, and finished.

    This is a brief overview without going into the details of each step (which I will, of course, cover later). Using this process, I made the propellers for my Project 941 model:


    Click image for larger version

Name:	55315521322_356b37ca7d_b.jpg
Views:	4
Size:	51.2 KB
ID:	195608

    Click image for larger version

Name:	55316836550_f9b3944d5c_b.jpg
Views:	4
Size:	55.0 KB
ID:	195609

    By the way, casting jewelry in gold or silver is actually easier than casting a complex model like this.

    This model contains several mistakes, starting from step one and continuing through other stages of the process. I will point them out and explain them to you.

    I hope you will find it informative and educational.

  • CollectiveBorg
    Lieutenant, Junior Grade
    • Dec 2025
    • 20

    #2

    Tomorrow, I will post the next part of this guide, where I will do my best to thoroughly explain all the methods used to create a wax pattern for investment casting.

    Comment

    • He Who Shall Not Be Named
      Moderator

      • Aug 2008
      • 13813

      #3
      Originally posted by CollectiveBorg
      Tomorrow, I will post the next part of this guide, where I will do my best to thoroughly explain all the methods used to create a wax pattern for investment casting.
      Will you also be part of tomorrow's Zoom meeting?
      Who is John Galt?

      Comment

      • CollectiveBorg
        Lieutenant, Junior Grade
        • Dec 2025
        • 20

        #4
        Originally posted by He Who Shall Not Be Named

        Will you also be part of tomorrow's Zoom meeting?
        *looks reproachfully*

        I asked you not to comment, so as not to disrupt the management structure.

        Unfortunately, no. I'd like to, but I'm not participating.

        *takes a deep breath." And then he decided to speak.

        I'm Russian. They don't like us. We're mean and all that (I don't want to talk about politics).

        I love modeling, I was asked to do something I'm good at, so I started this post.

        Now they'll probably delete me and ban me.

        Comment

        Working...