To calculate the weight of a zamak part, multiply its volume by the density of the alloy: in ZP3 (6.6 g/cm³) a 10 cm³ part weighs about 66 g. Many generic calculators use the density of pure zinc (7.13 g/cm³) and therefore overestimate the weight of a zamak part by about 8%.
Calculate the part weight
–
–
Indicative values: the actual weight may differ by a few percent because of tolerances and wall thickness. The result refers to the finished part, without runners and overflows, which are removed after casting.
How the calculation works: the volume comes from CAD, the density from the chosen alloy.
Density of zamak alloys
The four zinc die-casting alloys of EN 12844 have similar but not identical densities: for the same volume, a part in ZP2 weighs about 8% more than the same part in ZP8.
Densities as on our zinc alloys page; for strength and hardness see the mechanical properties of zamak alloys.
From CAD to part weight
The volume can be read directly from the 3D model: in SolidWorks under Tools > Evaluate > Mass Properties, in Inventor under iProperties > Physical, in Fusion under the body Properties.
If the software already shows a mass, check which material is assigned: it is often a generic steel or aluminium, and that weight does not apply to zamak. In that case use the volume, or the second tab of the calculator.
If you send us the STEP file with your quote request, we calculate the part weight together with the mould and the cycle.
Why weight matters in a quote
Weight tells you how much alloy each part needs, but it is not the only item in the price. It is a good starting point to compare options, not a price.
Mould and cavities
The number of cavities in the mould decides how many parts come out of each cycle, and therefore how much the mould weighs on each part.
Cycle time
Wall thickness and geometry set the cooling time: a lighter, more uniform part leaves the machine sooner.
Machining and finishes
Machining after casting and surface finishes can cost more than the alloy: a part that comes out of the machine finished saves money.
If you are thinking of switching from brass or steel to zamak, the second tab of the calculator shows straight away how the weight changes for the same geometry.
FAQ on zamak weight
How much does 1 cm³ of zamak weigh?
About 6.6 g for ZP3, 6.7 g for ZP5, 6.8 g for ZP2 and 6.3 g for ZP8. One cubic decimetre of ZP3 therefore weighs about 6.6 kg.
Why not use the density of zinc to calculate the weight?
Because zamak is not pure zinc: aluminium, which is much lighter, lowers the density. With pure zinc (7.13 g/cm³) the weight of a ZP3 part comes out about 8% too high.
Is the calculated weight the weight of the finished part?
Yes, it is the net part weight. Runners and overflows are removed after casting and are not included. Electroplated finishes add only a few microns and generally do not change the weight noticeably.
Do you have a drawing to evaluate?
Send us the STEP file: we work out weight, mould and cycle.