Automotive & Transportation Plating in Texas

Weight, geometry, thread size and cosmetic requirement decide it. Barrel suits small loose hardware and tolerates part-to-part contact; racking is used where parts nest or dent, where thickness has to be even on one specific face, or where a visible surface cannot carry contact marks. Thickness distribution differs between the two, which matters when a print puts a minimum on a threaded feature — see zinc electroplating.

The service condition sets a minimum zinc thickness, and the chromate type sets the conversion coating over it, which is where color and salt-spray life actually come from — two prints with the same thickness and different chromate types are not the same part. The classes and types are laid out on the ASTM B633 zinc plating specification page. Alkaline zinc and black zinc run at our Rowlett plant.

A compliant zinc is finished with a trivalent passivate rather than a hexavalent chromate, since hexavalent chromium is what both RoHS and the end-of-life vehicle rules restrict. If your drawing still names a hexavalent yellow chromate, that callout has to change before a compliant part can be supplied — raise it at quote and we will propose the trivalent equivalent rather than substituting silently. What Gleco holds and declares is on the certifications and approvals page.

Handling, mostly. A part that runs loose in a barrel costs less to process than one that has to be racked, masked or fixtured, and each added step — a heavier thickness class, a sealer or topcoat, a selective area, a post-plate bake — is a separate operation rather than a rounding error. Geometry that traps solution or nests together adds handling as well; the design guide covers the features that drive it. Volume changes the setup share, not the per-part processing.

Underhood and chassis parts that see heat, road salt or a joint with aluminum are where it earns the difference: zinc-nickel keeps sacrificial protection at temperatures that degrade a conventional zinc chromate, and it corrodes far more slowly in an aluminum couple. For interior and dry-side hardware the extra cost usually is not recovered, and standard zinc plating in the Dallas area is the better answer.

Yes — dimensional layout, thickness readings and the process record for a first article, submitted against your element list. Send the submission level with the RFQ, because that decides what has to be measured, recorded and retained before the first production release. Our quality system is what those records sit under.