CS195011B1 - Method of galvanoplastic manufacture of intricate structural surfaces - Google Patents

Description

The invention relates to a process for the production of complicated shapes, particularly suitable for the production of reliefs and features made by electroforming.

Up to now, metal reliefs have generally been produced in such a way that the original relief, made of non-metallic material, serves to produce a sand mold into which metal is cast. This creates a metallic original relief. Making sand molds is expensive and Saxons demanding. At the same time, this process is demanding on metal consumption. The accuracy of the casting is determined by the grain size of the sand used.

Relief castings must be cleaned of sand or polished.

The disadvantages of the above-mentioned drawbacks are eliminated by the method for the production of complicated surfaces according to the invention, which consists in that the functional part of the plastic mold is electrically conductive and a conductive binder layer is applied over the entire periphery of the mold. and plating in a bath.

Advantages of the method according to the invention consist mainly in the perfect accuracy of the impression of the embossed or embossed feature and in considerable metal savings, since the articles made according to the original have a metal wall thickness of 0.6 to 1.5 mm. This saves up to 90% of the metal required for the classical production process. This thickness of the electrolytically rolled metal layer is fully sufficient for the self-support of the shell. A further significant advantage is that the V-shaped notch provided with the edge of the mold is electrolytically deposited 1.95 OH.

19S 011 due to the low depth efficiency of the electrolyte and the rapid change in the deposition potential, the inhomogeneous and eliminated layer thickness is reduced proportionally and by the depth of the notch, so that this edge of the shell behind the notch can be easily removed by breaking. This eliminates the tedious machining of the shell edge.

By the method according to the invention, the reliefs are made by using galvanoplaetics. Negative copies of the relief are made from the metal original by casting into honeycomb or silicone rubber, preferably from Lukepren. The functional part of the molds so produced and conducting are made in one of the known ways, i.e., they provide a conductive lacquer, or chemically silver-plated, or chemically copper-plated and the like.

After attaching the suspension hook and the conductive contacts, the mold is suspended in the plating bath as a cathode. ^When the electrolytic process is finished, the mold is removed from the bath and after repeated rinsing, the mold is removed from the bath and the finished work is obtained.

The broken edge of the shell ee breaks and the edge ae is only cleaned by grinding.

The plaque can then be further processed, for example, patination, polishing and the like. In this way, reliefs have been successfully performed under laboratory conditions.

Execution example

Making a portrait according to the original sculptor Benda. A two-part mold made of lukoprene was made on the original in which the semicircular protrusions and depressions were formed in the separating plane to ensure the mutual position of the mold parts. The mold cavities and the separating surfaces were chemically silvered in conventional manner with an ammoniacal silver nitrate solution, and the separating surfaces were then coated with a conductive silver lacquer layer and the mold was folded just before the lacquer had dried and the edges of the forota were tightened with screws. A tube of both the platinum strip and the wire was inserted into the cavity of the mold so as to be located in the middle of the cavity and the platinum wire served as the power supply.

The forotone thus prepared was placed in a sulfate copper electrolyte bath, the anode potential was connected to the platinum conductor, and the cathode potential to the silver-plated interior of the mold, and an electrolyte was connected to the platinum anode tube.

After 48 hours, the mold was removed from the bath. Copper produced with an average wall thickness of approx. 1 mm. The copy was seamless on the separating surface and found only easily removable remnants of the conductive lacquer.

In this way, it is possible to produce sculptures from other metals, for example nickel, which can also be electroplated with brass, copper, silver and the like.

Claims (1)

Method of electroforming of complicated shapes, plastics, reliefs, features, characterized in that the functional part of the plastic mold is electrically conductive and on the dividing surfaces of the mold, which are provided with a V-shaped groove all around the circumference and a conductive binder layer is applied. plating in bath.