Fibreglass moulds are required for the production of fibreglass mouldings, but suppose you wanted to design and manufacture a boat hull, you would need to make a pattern also known as a plug or buck first, this is an exact model/replica of the end product, the pattern will have the exact dimensions and surface appearance of the finished product.
Fibreglass moulds are required for the production of fibreglass mouldings, but suppose you wanted to design and manufacture a boat hull, you would need to make a pattern also known as a plug or buck first, this is an exact model/replica of the end product, the pattern will have the exact dimensions and surface appearance of the finished product.
Once the pattern is made, it is prepared with several coats of mould release wax followed by a coat of PVA release agent, the pattern is now ready for the gel-coat to be applied, this will be painted or sprayed on depending upon the size of the mould to be made, but the gel-coat should be a tooling grade material and as such provide a long life for the production mould and good gloss retention, once the gel-coat has cured a second coat is applied and allowed to cure as well, the gel-coat will remain tacky, that is ok, the tacky surface of gel-coat will enable a good bond to the laminate to be achieved in the next process.
Now the gel-coat has cured but still a little tacky, the first layer of glass fibre is laid onto the back of the gel-coat and impregnated with resin, the saturated glass fibre is then rolled with a special roller to remove trapped air and consolidate the glass fibres, this initial layer is allowed to harden and cure, we call this process the first layer or skinning the mould, now the first layer has cured you can apply more layer of glass fibre impregnated with resin until the required thickness is achieved, these consecutive layers are also allowed to harden and cure, once these new laminates have cured the mould can be stabilised with either a timber or metal frame-work which is bonded to the back of the mould to keep it rigid and stable, but remember a mould can also be more than one piece, depending upon the design of the product (complexity of design , undercuts, flash line, ect) but if the mould is flanged into multiple pieces, you must ensure that locators are employed on all flanges to ensure all mould pieces align.
Now the mould is complete the pattern can be released, compressed air or wedges may be required to break the seal, once the pattern is released from the mould we start again by applying several coats of mould release wax to the new mould, remember its good practice to apply PVA release agent to the mould face of the new mould for the first pull, this will ensure that the first fibreglass product will come out with out sticking.
Also fibreglass moulds are manufactured for moulding products in pre-cast concrete, these moulds are called pre-cast concrete moulds, and are used to produce paving slabs, sea-defence sections and components that are to intricate for the mould to be formed in timber, in short fibreglass moulds come in all shapes and sizes and are used to manufacture products for a wide range of applications in industry, some of these products range from,
Boat hulls and associated components, water slides and theme park rides, architectural columns and arch's, Lorry wind deflectors and body kits, airport furniture, pre-cast concrete moulds, wind turbine blades, planters, enclosures, shower trays and baths, modular buildings, machine guards and covers, and so much more...
Congratulations, you now have a brief understanding of fibreglass moulds, and the process's employed to manufacture a basic mould, but you must also be mindful of material choice and mould design, as discussed before, some moulds will need to be more then one piece and hence need to be flanged into multiple pieces, so design criteria at the product stage is key, but don't be put off by this, fibreglass is a great composite material that allows designers the scope to achieve products that are stunning and cost effective.
Fibreglass moulds are required for the production of fibreglass mouldings, but suppose you wanted to design and manufacture a boat hull, you would need to make a pattern also known as a plug or buck first, this is an exact model/replica of the end product, the pattern will have the exact dimensions and surface appearance of the finished product.
Once the pattern is made, it is prepared with several coats of mould release wax followed by a coat of PVA release agent, the pattern is now ready for the gel-coat to be applied, this will be painted or sprayed on depending upon the size of the mould to be made, but the gel-coat should be a tooling grade material and as such provide a long life for the production mould and good gloss retention, once the gel-coat has cured a second coat is applied and allowed to cure as well, the gel-coat will remain tacky, that is ok, the tacky surface of gel-coat will enable a good bond to the laminate to be achieved in the next process.
Now the gel-coat has cured but still a little tacky, the first layer of glass fibre is laid onto the back of the gel-coat and impregnated with resin, the saturated glass fibre is then rolled with a special roller to remove trapped air and consolidate the glass fibres, this initial layer is allowed to harden and cure, we call this process the first layer or skinning the mould, now the first layer has cured you can apply more layer of glass fibre impregnated with resin until the required thickness is achieved, these consecutive layers are also allowed to harden and cure, once these new laminates have cured the mould can be stabilised with either a timber or metal frame-work which is bonded to the back of the mould to keep it rigid and stable, but remember a mould can also be more than one piece, depending upon the design of the product (complexity of design , undercuts, flash line, ect) but if the mould is flanged into multiple pieces, you must ensure that locators are employed on all flanges to ensure all mould pieces align.
Now the mould is complete the pattern can be released, compressed air or wedges may be required to break the seal, once the pattern is released from the mould we start again by applying several coats of mould release wax to the new mould, remember its good practice to apply PVA release agent to the mould face of the new mould for the first pull, this will ensure that the first fibreglass product will come out with out sticking.
Also fibreglass moulds are manufactured for moulding products in pre-cast concrete, these moulds are called pre-cast concrete moulds, and are used to produce paving slabs, sea-defence sections and components that are to intricate for the mould to be formed in timber, in short fibreglass moulds come in all shapes and sizes and are used to manufacture products for a wide range of applications in industry, some of these products range from,
Boat hulls and associated components, water slides and theme park rides, architectural columns and arch's, Lorry wind deflectors and body kits, airport furniture, pre-cast concrete moulds, wind turbine blades, planters, enclosures, shower trays and baths, modular buildings, machine guards and covers, and so much more...
Congratulations, you now have a brief understanding of fibreglass moulds, and the process's employed to manufacture a basic mould, but you must also be mindful of material choice and mould design, as discussed before, some moulds will need to be more then one piece and hence need to be flanged into multiple pieces, so design criteria at the product stage is key, but don't be put off by this, fibreglass is a great composite material that allows designers the scope to achieve products that are stunning and cost effective.
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