LostWax Casting is an ancient technique that has been used to create verycomplicated metal castings and involved pieces that would other wise beimpossible either because of economic reasons or manufacturing reasons.Everyone from small jewelers to casting mold for Automotive parts large industrial foundries can use Lost WaxCasting. This process is also called Investment Casting when it is used incommercial industries. While jewelry makers are the primary ones to use theLost Wax Casting, many others use it to achieve a number aims and goals.Lost Wax Casting is the ideal and preferred method for artists who areinterested in making items like sculptures or rings from a variety of alloyslike bronze, steel, or copper. This process is quite involved but not all thatcomplex as long as you have some kind of metal casting know-how.
For anyonewanting to experiment with different casting methods Lost Wax Casting is agreat option because it involves a few materials and methods that are notnormally found in other methods like Sand Casting. The most noticeable difference of Lost Wax Casting from other castings isexactly what’s in the name; the wax. To use Lost Wax Casting you do notnecessarily have to be an artists but some skill in sculpting might be nice.You are going to start off by creating a sculpture from wax that will be theoriginal. You will then create a mold of the original. The mold is usually created fromplaster with latex lining to help preserve the details of the original. If thisis your first attempt at Lost Wax Casting you may want to make an originalwithout a lot of detail just to get the feel for the entire process and so youdo not become discouraged if something does not work out. Remember metalcasting is a skill that must be learned by research, trial, and error. Chancesare that you will not be completely successful, the first time around. Theoriginal piece is usually lost after the construction of the mold. This isnormal and if you do want to prevent this from happening you can create theoriginal from material other then wax like a metal alloy.When the mold is ready you are then going to pour molten wax, you’re not readyfor metal just yet, into the mold. The amount of wax needed for this stepdepends on the desired thickness. Once the copy is ready, you are going toremove it very carefully from the mold. You will remove any of the impuritiesfrom the copy. This is called chasing.You will then sprue the copy. Spruing is the act of carefully placing pathsthat will let the molten metal in and air out. Afterwards, a ceramic shell iscreated around the copy. The shell isn’t really ceramic but a combination ofliquid silica and sand. Traditionally, and in some areas still, animal dung anddirt is used to create the shell. The choice of which shell material you wantto use is up to you. The shell is hardened in the kiln and the wax melts out.
If you want to reuse the wax then collect it during this step. Wax can bereused a number of times and if you are on a budget or are just trying outdifferent designs and methods, collecting the wax is encouraged. Once the waxis gone and all that remains is the hollow shell you will want to run waterthrough it to make sure there are no leaks. If there are then you will need topatch them before pouring the molten metal. You are going to want to reheat the shell before pouring the metal to avoidshattering the shell. The shell is still on the sprue tree so pouring the metalis an easy process. When the metal has hardened, then break the shell carefullyand remove the cast. Afterwards, it is up to you to finish the piece to yourliking and preference. The Lost Wax Casting process is an enjoyable experience but it does use a fewtools that you might need to purchase before hand, like the wax and spruingtree. At the very least, you might want to try Lost Wax Casting once or twiceto get a feel for it. This way you have another casting process at yourdisposal.
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