Zinc and Zamak castings are smaller and run cooler than aluminium, so the problem is rarely thermal. It is the surface the part carries to the plating line. Two grades, one of them the workhorse at a confirmed 1:100.
| Model | Position | Dilution | Typical use |
|---|---|---|---|
| ZP-118 | Workhorse | 1:100 | Small and medium zinc parts; clean release and consistent finish |
| ZP-218 | Extended series | on request | Additional working point in the range |
Zinc castings are frequently plated. That single fact changes what you should ask of the release agent, because plating is unforgiving about what it finds on the surface.
A zinc part that releases cleanly but carries a film into the plating line has converted a casting success into a finishing failure. Silicone residue is the usual mechanism, and it is not visible at the die.
Small parts run short cycles and high shot counts. What matters over a shift is that shot 2,000 behaves like shot 20 — so dilution control and spray stability outrank any single-shot performance claim.
Plants that run zinc alongside another alloy usually want one supplier for the basket rather than three relationships to manage. We supply the die face grades for all three alloys from the same factory, plus plunger lubricants in black, white and translucent white, granular salt and de-slagging agents.
The questions buyers actually ask before the first drum. Answered without marketing language.
ZP-118 is the zinc workhorse, factory-confirmed at 1:100, with ZP-218 as the extended grade. Zinc castings are usually smaller and run at lower metal temperature than aluminium, so the priority shifts from high-temperature film stability to clean release and a surface that plating can accept.
The plating step is the reason to be careful rather than a reason for a different alloy chemistry. Zinc castings frequently go to electroplating, and silicone carried on the surface from the die spray is a known cause of adhesion failure at that stage. If your parts are plated, specify a silicone-free grade at the enquiry.
Yes, substantially — zinc alloys are cast at much lower temperatures than aluminium, which is why the release agent is not being asked to survive the same thermal load. It is a reason zinc grades can be formulated for cleanliness and release rather than for extreme heat resistance.