To give you the best chance of success in mould making, please follow the following guide lines. You will be using industrial chemicals that are definitely not intended for children, so be careful.
Knowledge: As these products are designed for use in big industrial concerns with experienced laboratory staff, little how to do it material is produced by the manufacturers. We are endeavouring to overcome this deficiency with our FREE Tech Tips and other material. Read all you can. as we put them on line.
Start Small: Do not undertake a large project without testing a small mould or casting. You will only waste money or worse still damage an important model. To help you, we are producing Kits which contain a small amount of the materials and instructions with methods that we have tested and know will work.
Ask Questions: We can't tell you how to make moulds over the phone, but we are always available to answer any specific questions you may have. Kits are still the best answer coupled with a range of books we are producing to cover all aspects of mould making and casting.
HOW TO START MAKING MOULDS AND CASTING
Each and every moulding and casting compound requires handling in its own unique way that may be quite different from others in the category. This is why I say the kits are the preferred way to start using new materials, we have done all the testing. Once you have made a satisfactory mould and are familiar with the product is the time to start experimenting with new, small, test mixes.
CAUTION: SAVE TIME AND MONEY BY STARTING SMALL AND SIMPLE!!!!!
As a general rule moulds are made by either pouring liquid rubber over a model surrounded by a dam made of wood, clay, cardboard etc to contain the rubber or by brushing thickened rubber onto the model and then encasing it with a shell made of plaster, fibreglass or thickened resin to help it retain its shape when casting.
WHAT CAN GO WRONG
If you have an idea of the main things that can wrong it will help you select the correct rubbers and casting materials.
CORRECT MIXING RATIOS: We emphasise this aspect in all kits, since it is probably one of the most important causes of mould making failure. Most rubbers come in two part mixes and are designed to be weighed accurately prior to mixing. It is a good idea to purchase a set of digital scales capable of weighing 1gm to 1 kg accurately. Some of the newer rubbers can be mixed by volume so check the instructions carefully.
CORRECT RELEASE AGENTS: It is very important to identify the correct release agent to be used for each rubber and apply it as directed. Polyurethane is particularly adhesive and will wreck a model if the release agent is incorrectly applied. If using a new material test on a small model. In this area it is better to be sure than sorry.
INADEQUATE MIXING: If Part A and Part B of the rubbers are not mixed thoroughly you will get soft streaks of unmixed material showing up in the mould. These weak areas are usually from unmixed rubber left on the sides or bottom of the mixing container.
CASTING MATERIALS HARDEN BEFORE POURING: This usually happens with quick setting polyurethane resins that harden while you are still mixing. You MUST watch the clock. 3 minutes is a very short period of time.
LEAKING: This can happen with seams in mould boxes that are not properly secured with Plastelina or clay. Not a pretty sight to have silicone leaking all over the bench that could have been prevented with a bit more care.
INCORRECT MATERIALS: Selection of the correct material is essential. Small batch testing saves a lot of money. People who jump straight into a major job without prior experience of the materials being used are asking for trouble in the world of mould making. There are just too many variables. Start small and simple.
Read and understand the MSDS (Material Safety Data Sheet) the product label and Technical Bulletins. Aldax has chosen products that can be safely use if simple precautions are taken as recommended in these sources of information. All products should be used with good ventilation. All skin and eye contact, ingestion and breathing of dusts and vapours should be avoided.
Use the recommended safety equipment such as eye shields and masks. Read and follow the directions. If you have any questions ring before starting your project
The uncured rubbers may cause skin or respiratory irritation if improperly handled. Avoid skin and eye contact with uncured material. If skin contact does occur remove with a waterless hand cleaner or alcohol then soap and water. In the case of eye contact, flood with plenty of water and call a doctor. o not use in areas where there is contact with food or prolonged body contact.
The mould making and casting materials that Aldax Moulds distribute are manufactured and tested to high quality specifications by the manufacturers. Always determine suitability for your application by testing before using. Aldax Moulds has no control over working conditions or methods used and will not be held liable for damages exceeding the value of the product.