Post Polishing SPDT (Single Point Diamond Turned) Surfaces

Zeeko is announcing here two excellent post polishing solutions to issues that are commonly identified as a requirement of single point diamond turned optical surfaces. There are two different issues that manufacturers experience most commonly when diamond turning electroless nickel (NiP) coatings on steel or aluminium substrates:

Case #1 – Surface Mid-spatial Content

This issue will be familiar to all. It is often referred to as “Rainbow reflection” from the surface. It is due to the regular signature left on the surface by the diamond turning process and can result in the surface creating unwanted optical effects most often this is a “diffraction grating” effect creating a full colour spectrum like a rainbow.

The Zeeko Solution – Mid-Spatial Removal by “Bonnet” Polishing
This accessory kit is simply known as the “Zeeko – Mid-Spatial Removal Kit” and can be applied to any Zeeko IRP (7-axis polishing machine) or RPC (robot polishing cell). It can also be applied to third party polishers (although in such an example the tools may need adapters and the software may not be automatic).

The “Zeeko – Mid-Spatial Removal Kit” is comprised of:

Zeeko Slurries:

Zeeko Aluminium Oxide Slurry – 5 Litres – (it is recommended that this slurry can be recirculated and only discarded when it ceases to be effective). The resulting roughness measurement will be approx. Ra = 1.5nm – 2.0nm.
Extra cost option – if a superior finish is required then Zeeko Nano slurry should be used (or even Zeeko Super Nano slurry (see Case #2 below) – 50 Litres of either (or both) slurry can be purchased at extra cost – (it is recommended that after single use this slurry – (Zeeko nano slurry) – is drained to a waste container). In the event that Zeeko Super nano slurry is used in addition to the Nano slurry, then the full “Zeeko Superfine Finishing System” should be used.

Hardware accessories:

Peristaltic Pump – Qty 1 with double head (one head for the slurry supply and one for supply the suction slurry return line).
Piping – (for Peristaltic Pump) – for the slurry supply and return line.
Containment Unit (“Open design”) – for collecting the slurry into a small containment volume from which it can be directed back to the the main peristaltic pump slurry reservoir (if the Zeeko Aluminium Oxide Slurry is used).
Water Treatment System (*optional) – for the supply of pure water to the ultrasonic spot shower system if specified for surface cleaning and wash down (see more details below).

Note: it is recommended that the used cleaning water is not re-used.

Case #2 – The “Superfine” surface

This is a new/ emerging requirement that we are meeting at multiple customers. Not only the need to prepare a mid-spatial free surface – but the need for that surface to be free of any marks whatsoever other than the finest of “nano-scratches” that only a microsope can identify.

To answer these market needs, Zeeko has developed a new polishing solution the “Zeeko – Superfine Finishing System” and is selling accessory kits for its machines to enabled these solutions to be delivered on both it’s IRP / RPC machines but also on third party machines. These kits all see Zeeko making and selling its own polishing slurries (nano-slurries) for the very first time.

The Superfine Finishing System

This second machine upgrade is known as the “Zeeko – Superfine Finishing Kit”.

The “Zeeko – Superfine Finishing Kit” is comprised of:

Zeeko Slurries:

Nano slurry – 50 Litres – (it is recommended that after single use this slurry is drained to a waste container).
Super-nano slurry – 50 litres – (it is recommended that after single use this slurry is drained to a waste container).

Hardware accessories:

Peristaltic Pumps – Qty 2 (one for the slurry supply and one for the supply of pure water to the atomiser nozzles).
Piping (for Peristaltic Pumps) – for the slurry supply and for the pure water atomiser and for the ultrasonic spot shower for wash down.
Slurry filter pack – triple filter system – (for slurry and separately for the atomised water for humidity control).
Homogeniser – for ultrasonically agitating the slurry particles to break apart any that have re-agglomerated since the slurry was produced – this is phenomenon that can occur within minutes of the slurry being prepared.
Pure Water Treatment System (*optional) – this unit is to supply pure water to the atomiser and to the wash down system. (*it is optional because de-ionised water can be used if available in sufficient volume).

Note: it is recommended that water is is not re-used

Ultra-sonic “Spot Shower” – this is a automatic system that uses ultrasonically agitated water directed at the polished surface to wash down the surface and remove any residual slurry after processing.
Dedicated bracket – to mount the slurry nozzles, atomizer nozzles and ultrasonic spot shower to the H-axis (Zeeko machines) to ensure these jets are all kept pointing in the correct direction and follow the polishing spot as predicted by the automated ZephyrCAM software.
Atomiser nozzles – to keep the atmosphere humid and the surfaces moist to prevent the colloidal slurry drying on the surface and creating scratches during their removal.
pH tester – (for checking the pH level of the slurry).
Zeeko Blue Coated Polishing tools – 3 tools of each of the following sizes coated in Zeeko N]Blue polishing pad. All tools are on 12mm dia. Stems and sizes are R5, r10 and disc.
Zeeko Nanoguard – a fine surface “gel” like preparation designed to protects the surface from dried slurry and other fine damage prior to polishing.
ZephyrCAM One Page – software upgrade to a fully automated version of the software that can run this complex process fully automatically.

Please Note: this process should be carefully controlled in a clean atmosphere.