Finishing

Jewellery Finishing Equipment

OPDEL supplies jewellery finishing equipment for every surface stage that follows casting: investment (plaster) cleaning, vibratory finishing, disc finishing, centrifugal tumbling, magnetic pin shining, sand blasting, bench polishing with dust extraction, and the media, compounds and plating solutions those machines consume. The range is used by jewellery manufacturers, casting houses, refiners and precious-metal workshops working in gold, silver, brass and stainless steel. This page is the hub: it explains what each machine class does, where it sits in the process, and which OPDEL model page to open next.

Where finishing sits in the production line

Finishing begins the moment a flask comes out of the casting machine. Trees cast on systems such as the OPSPRCast D universal casting machine, the OPPressCast OP3 and OP5 pressure-over-vacuum casting systems, the OPCast D centrifugal casting machine or the OPC A03 and F1000/F2000 lost-wax casting machines still carry investment, sprues, oxide and tool marks. Everything after that point — de-investing, deburring, roughing, smoothing, shining, plating — is finishing.

The order matters more than any single machine. A workshop that skips a proper roughing stage will try to recover it in the shining stage, which costs media life, cycle time and metal. Selecting a finishing line means choosing a sequence, not a box.

The OPDEL finishing range

Investment cleaning

The investment cleaner (Starjet MF 110) washes trees coming out of plaster casting. The machine is constructed entirely of steel to AISI 304, which is what allows it to live in a permanently wet, alkaline-slurry environment without corroding. This is the first machine of the finishing line and the one most often undersized when a plant adds casting capacity.

Vibratory finishing

The circular vibrator is the general-purpose wet finishing machine, used for roughing, sanding and polishing on jewellery parts and on ferrous alloys, particularly stainless steel. An adjustable-masses vibrator transmits vibration into a polyurethane tank, so the load takes three superimposed motions at once — centrifugal, helical and vibrant. That combined motion, together with water, abrasive media and either liquid compound or paste, is what produces the finish. Adjusting the masses changes the aggressiveness of the action without changing the machine.

Disc finishing

Disc finishing is the high-energy option: deburring of micro-mechanical parts and mirror finishes. Rotation runs to a maximum of 450 rpm, and the gap is set by rotating the tumbler down to a 0.035 mm setting — the tolerance that keeps small parts and media from wedging. The tumbler is complete polyurethane and uses a long-lasting steel ring in place of the conventional ceramic one. Control is by feather-touch keyboard with an LCD panel that stores 25 processing programs, shows barrel number, processing time and running time, and lets you set forward rotation time, reverse rotation time and slow end time separately. Slow end time drops the machine to low speed for the final period of the cycle so the last minutes work as fine polishing rather than continued cutting.

Centrifugal tumbling

The centrifugal tumbler (Roll Fast) is built for comprehensive treatment of very small objects — roughing, grinding and polishing. Four containers rotate on their own axes in the opposite direction to the main course, and the containers are polyurethane, anti-wear and anti-ageing, with a shaped interior and the Swing System. That counter-rotation is why it reaches a fine finish on parts too small to hold their own in a vibratory bowl.

Magnetic pin shining

The magnetic shiner is a shining-stage machine only. It works with stainless steel needles, whose shape is specifically intended for internal surfaces that cannot be reached by hand — inside ring shanks, hollow forms, chain links, box clasps. It does not cut; it burnishes.

Blasting

Sand blasting machines (Mycro W-D and Dryblast 600-EV1) cover cleaning and mechanical pickling, finishing, peening, decorative blasting, deburring and hardening across a range of metals. Micro sandblasting and shot blasting with micro-balls is the standard preparation step before a coating or plating process. The model page carries the sand-grain to nozzle-size table, which is the specification to check before ordering abrasive.

Bench polishing

The polishing bench is available as a single- or double-place bench with a suction system for dust recovery. Construction is a strong metallic structure with a wooden work surface lined in laminated plastic, a protection hood with recessed lamp and plexiglass panel, high sucked-air volume, correctly sized bag filters on a quick-release fixing, and an emergency motor stop. In a precious-metal shop the filter system is not a housekeeping item — it is where the sweeps come from.

Media, compounds and consumables

Finishing consumables include stainless steel needles for magnetic shiners and stainless steel balls to AISI 420/C, guaranteed against oxidation when used with MF products, for vibration and rotation machines running with water and surface-active compounds at the shining step. Opdel Macrobrill polishing media for vibratory tumblers is a water-based, non-magnetic media with high hardness and low specific gravity: it polishes and smooths in one cycle, avoids the orange-peel texture that longer vibratory cycles can produce, and is oxidation-free, which removes the acid post-treatment step and the water discharge that goes with it. It is rinsed with water and reused, and is paired with the VILUX compound for maximum brightness.

Plating and colour

Plating solutions cover rhodium gel and rhodium solution, including white, black and copper colours, plus the OD-GP gel colour range from 24k ingot colour through 1N to 5N pink and red rose, supplied ready to use in 10, 20, 50 and 100 ml. The gel form is thixotropic and saves up to 50% consumption against classical brush or pen plating. Electroplating solutions run to two families: OD-PLA weak-acid processes depositing 22–24 karat films at 1 or 4 microns from baths of 2–4 g gold/litre, and OD-FLA alkaline flash processes for deposits under 0.2 microns from baths of 0.6–0.7 g gold/litre.

Sheet and strip

Rolling mills finish gold and silver plate. The roll cage is oversized against maximum load, rolls are water-cooled by circulation, and a special transmission joint keeps full power at the rolls even when they are opened to 45 mm. Roll parallelism is held either by micrometer setting or by a quick-release gear. Hand-operated, single-head, double-head, gearbox and strip versions are listed on the model page.

Verified specifications

Only figures published on OPDEL model pages are listed. Rows marked for verification are gaps OPDEL must fill before this table is used in a quotation.

What it changes commercially

Finishing is where a jewellery plant loses or keeps margin, for four reasons a capital-equipment buyer should price out before comparing machine costs.

Metal recovery. Every dry stage — bench polishing, blasting — generates precious-metal-bearing dust. The polishing bench is specified with a suction system for dust recovery and quick-release bag filters precisely so that dust is captured rather than lost to the room. Recovery rate, not purchase price, is the number that decides payback on a bench.

Labour per piece. Hand-finishing scales linearly with headcount; barrel and vibratory processes scale with tank volume. The disc finishing machine’s ability to store 25 programs and to run defined forward, reverse and slow-end periods means a repeatable cycle is set once by a supervisor and executed by any operator afterwards.

Consistency across batches. Programmed cycles and fixed media formulations remove operator variance. This matters most where a buyer is supplying a brand with an inspection standard rather than selling loose.

Running cost. Media wear, compound consumption, water use and effluent treatment are the recurring line items. Oxidation-free media that removes acid post-treatment and reduces water discharge changes the effluent bill, not just the finish.

Safety and environment. Extraction on the polishing bench, enclosed blasting and closed wet processes keep dust and abrasive out of the workshop air.

Selection, trials and support

Machine class follows part geometry and target finish, not budget: small solid parts to centrifugal tumbling, flat and mixed work to vibratory, deburring and mirror work to disc finishing, internal surfaces to magnetic shining, pre-plating preparation to blasting. Where the choice is genuinely close, run the part.

OPDEL operates a Finish-Lab as part of its service programme: a finishing laboratory used for start-up courses, instruction of operating personnel on finishing machines, and testing on customer samples, so a buyer can see the result on their own pieces before committing. After-sales service covers installation, replacement parts, breakage or accidental damage, and advice on production problems.

Frequently asked questions

How do I choose between a circular vibrator, a centrifugal tumbler and a disc finishing machine?

By part size and target finish. The circular vibrator is the universal wet machine for roughing, sanding and polishing across mixed jewellery work. The centrifugal tumbler is built for very small objects, using four counter-rotating containers to reach parts a vibratory bowl handles poorly. Disc finishing is for deburring micro-mechanical parts and for mirror finishes, running to 450 rpm with a 0.035 mm gap setting. Many plants run more than one.

What capacity should I order?

Capacity should be sized on grams or pieces per shift and on cycle time, not on tank volume alone. Published working capacities per model are not currently listed on the model pages.

What power supply and services do these machines need?

Each machine requires an electrical supply, and the wet machines require water and drainage; blasting requires compressed air. Exact ratings are model-specific.

Can I test my own parts before buying?

Yes. The Finish-Lab exists for exactly this: testing on customer samples and instruction of operating personnel on finishing machines. Sample handling for precious-metal parts should be agreed in advance.

Which media and compound should I run?

Media is matched to the stage. Stainless steel balls in AISI 420/C run in vibration and rotation machines with water and surface-active compounds at the shining step; stainless steel needles run in magnetic shiners for internal surfaces. Macrobrill is a water-based, non-magnetic polishing media that polishes and smooths in a single cycle and is paired with the VILUX compound for maximum brightness.

How long does media last, and how is it replenished?

Media wear depends on load, cycle time and metal. Macrobrill is specified as highly wear-resistant and is rinsed with water and reused.

Are spare parts and consumables held in stock?

After-sales service covers replacement parts and accidental damage. Stock position and delivery time are not published.

What is the delivery lead time and what warranty applies?

Is installation and operator training included?

Start-up courses and instruction of operating personnel on finishing machines are part of the Finish-Lab service. Whether on-site commissioning is included in the machine price is a commercial term.

Request a quote

Tell us the metal, the part type, your daily volume and the finish you need to hit, and OPDEL will propose a finishing sequence rather than a single machine. Enquiries, specification requests and Finish-Lab sample trials all go through the OPDEL contact page, which lists the Vadodara office address along with the current phone number and sales email address.

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