Birchwood Technologies now offers three mini systems for use in small batch metal finishing at low temperatures. Mini systems are designed for manufacturers looking to add in house capabilities but do not have the necessary volume or space for a full sized process line. Birchwood Technologies offers these blackening solutions for the Presto Black and TruTemp processes for iron and steel parts, and the Lumiclad process for aluminum parts. 

 

The cold Presto Black process forms a non-dimensional coating thickness of less than 0.5 micron thickness and is designed for components that require a black finish for visual appeal. Presto Black is a short fifteen-minute process that provides high corrosion resistance and is tested for up to 800 hours humidity exposure when sealed with an appropriate rust preventive. The Presto Black process offers a friable crystal structure that serves as a sacrificial barrier on sliding surfaces to protect the underlying steel itself from galling and deformation.

 

The low temperature TruTemp process forms a durable satin black magnetite coating, 0.5 micron thick, with no effect on material hardness or tensile strength. The sealed finish withstands up to 100 hours of neutral salt spray or several hundred hours of humidity, and protects the metal surface during shipment & storage as well as in service. TruTemp black oxide operates effectively with alkaline chemistry that does not embrittle metal or create unsightly salt bloom in and around recessed part areas.

 

The Lumiclad process forms a non-dimensional black oxide finish on all aluminum surfaces that is durable, clean and tightly adherent to the metal substrate. The Lumiclad process develops a uniform coating thickness of 1.5 microns that will not close down hole diameters or change critical part dimensions. The smooth black finish has a slightly porous crystal structure that absorbs an optional topcoat such as a dry-to-touch sealant, light oil, or clear polymer. 

 

All three processes utilize a conventional seven-tank immersion process line, and operate at low or room temperature, making the processes easy and safe to operate in-house. Mini systems are designed for short run sporadic production because the lines can be sealed and stored, with the chemicals in the buckets, for six to twelve months.