Vulcanized Rubber Stamps
The former red rubber stamp that everyone is familiar with will have been man-made in a vulcanizing press. The first rubber stamp vulcanizing press was patented in 1890 by Charles Schultze in New Orleans Usa. Vulcanizing is today one of the most cost efficient methods of production rubber stamps for mass produced stamps. Each batch of stamps is produced using a mould. This formula of found is more powerful to stamp production where the same moulds are used over and over again. production convention made stamps with a vulcanizing press requiring 'once only' moulds will drive the cost of found up significantly.
Laser Hand Tools
Making the mould - before a mould can be made you must have a specialist plate man-made from metal or polymer, the specialist plate has the primary relief (the artwork is raised) to make an impression in the mould. Having a specialist plate made each time a mould is required is what drives up the cost of found for vulcanized stamps. Pressing the specialist plate into a Matrix board creates the mould that will accept the rubber. Heat and pressure is applied to the specialist plate and matrix board inside a Vulcanizing press. The Matrix follows the shape of the relief in case,granted by the specialist plate, this then hardens on cooling.
Making Rubber Stamps - Creating stamps is a easy process once the mould is made. Raw rubber stamp gum is located on top of the mould and then located inside the stamp press. Hydraulic pressure is located upon the rubber and the mould from within the stamp press causing the rubber to melt into the areas of the mould that consist of the images and text, curing and hardening takes about 10 minutes. Once cured the sheet of rubber is pulled away from the mould and cut up into private stamps to be affixed to mounts.
Cost of a vulcanizing ideas is almost ,000 Aud
Advantages - Low cost of production for mass produced stamps, good ink transfer.
Disadvantages - Cost of producing specialist plates and moulds for convention made stamps.
Laser Engraved Rubber Stamps
The former raw rubber used for vulcanizing stamp dies is quite unacceptable for the production of laser stamp dies, the laser process requires a very even thickness and blemish free face to furnish an proper printed image from a stamp die. The rubber must also be subjected to a exact curing process before it can be exposed to the elevated climatic characteristic of a laser beam.
The depth of the engraving is carefully by the laser speed, its wattage and the density of the rubber. For example, a 50 or 100W engraver will engrave the rubber deeper and faster than a 25W machine, which may require a second pass to accomplish a similar result. Normally supplied in an A4 size sheet form, a good quality laser rubber is required for engraving stamp dies and must also have convenient compression power and ink exchange properties.
To aid the engraving process, it is primary to remove the excess dust which is enduringly created by the laser cutting performance with an efficient exhaust filtration system. As very few, if any, Co2 laser engraving machines were initially purpose built for engraving and cutting rubber, installing and maintaining an efficient dust extraction ideas pays long term dividends. Mirrors, lenses and any exposed bearing surfaces should be cleaned wholly as part of a regular maintenance program. Any neglect in this area will be detrimental to widespread trouble free laser operation, as the build up of dust and residue will influence running efficiency and the quality of the done stamp die. Lasers are controlled directly from a computer, the software drivers supplied with lasers work with many illustrated programs such as CorelDraw.
Approximate cost of a 25 watt Laser convenient for stamp production is ,000
Advantages - production is computer controlled, convention made stamps can be made easily
Disadvantages - High capital investment, maintenance costs and running will be much higher than vulcanizing or polymer methods of manufacture.
Liquid Polymer Rubber Stamps
Converting rubber stamp polymer from a liquid into a solid to make stamps is quite fascinating. Polymer stamps are man-made in the middle of two sheets of glass using precision controlled Uv light which passes through a negative containing the stamp artwork solidifying the polymer. Negative production has been simplified with the introduction of water based negative technology, photographic chemicals for producing negatives are now a thing of the past.
The first step in production polymer rubber stamps is to print your images, clipart or text onto Vellum, an almost transparent paper like film.
To furnish quality stamp artwork you must use a laser printer, inks from bubble jet printers are translucent allowing Uv light to pass where it should not. Water based negatives are honestly washed out after being exposed for a few minutes in a Uv exposure stamp machine.
Polymer contained in a sachet is now replacing the older cumbersome formula of using foam tape to generate a dam and pouring of rubber stamp polymers, the sachets have also addressed the age old qoute of removing air bubbles from the poured polymer.
The negative of your artwork and polymer sachet is sandwiched in the middle of two sheets of glass spaced 2-3mm apart which is then exposed in the engine for a few minutes. Once you have completed the exposure it is a easy process of cutting open the sachet and washing away the excess unexposed polymer before returning the stamp die back to the engine for a 10 dinky curing. Once the stamps are cured they can be cut up individually. Polymer sachets are ready in a range of sizes up to A4 size.
Processing time is about 30 minutes for a batch of polymer stamps.
Cost of polymer stamp production machines range from ,500 Aud for an Australian made unit designed specifically for stamp production up to high end imported units with computer controlled washout for ,000 Aud.
Advantages - Lower capital investment, polymers make almost clear stamps production them ideal for scrapbooking and card making. Stamp relief can be honestly controlled while exposure.
Disadvantages - Early polymers did not accept inks as well as polymers ready today, this along with being new technology caused preliminary resistance to polymer stamps.
Summary
Most large stamp manufacturers have a mix of the above equipment. The unmounted rubber stamp dies produced with any of these manufacturing methods can be cut up and affixed to easy hand stamps, dater stamps or self inking stamps. Craft stamps are Normally affixed to wooden blocks or in the case of polymer stamps affixed to clear acrylic blocks with adhesives or InstaGrip mounting mat. Discrete industry produces stamp mounts. Astron Industries in Australia builder the clear hand stamp 'Vuestamp' and also distribute the Ideal range of self inking mounts. Other brands of self inking mounts are Trodat, Colop and Shiny.
How to Make Rubber Stamps: Comparing Methods of invent