Moulds & Quality


The mould you have for your part is the first step in quality. So you designed the worlds best widget, you made a pattern or plug, spent hours surfacing it to exactly what you want, checked everything twice, then had the mould made. The plug or pattern, as is common, was a one off master. It is only the automotive industry that can afford to build metal faced master tools. So if you want to build another mould you make a master part from the first mould. Everything now depends on the quality of that first mould. The parts you produce and the master part and subsequent moulds. If it is low quality, whatever the problems they will be faithfully repeated in your product. With the plug or pattern gone, refinishing parts for another mould or for sale is an unacceptable expense.

In over 25 years in the fibreglass business we have seen many products offered and tested. We engage in a constant Research and Development program of materials and techniques. We have also seen many examples of what not to do. Consequently we only use the best and tested materials. Our reputation depends on the material selection that we determine for the job, not to let us down so we don't let you down.

While keeping an open mind to new developments, we exhaustively test and trial new materials and processes on our own moulds and parts before offering them to customers. This is another advantage of manufacturing for our own use. We are both supplier and customer. A relationship that ensures we are responsible for the best job using our own money before we ask customers to trust us with theirs.

We don’t cut corners, we don’t produce cheap tooling or moulds. Cost cutting will always come back to haunt you in this business, either in mould life, rework, poor fit or poor finish. A good demonstration of this principle is mould construction. There is really only one way to build a long life production mould, below are some ideas and images relating to good mould design:

Ryman Composite's Quality Mould Design - Example 1




Ryman Composite's Quality Mould Design - Example 2





If you have been offered less than production quality specification either the mould is low volume or you can expect deterioration of the mould and finished product over time. You get what you pay for is very true in composite moulding.

Mould manufacture is a process that should be undertaken with skill and patience on the part of both the manufacturer and the client. As an example the following sequence shows the stages of manufacture of a segmented dome mould. 

Stage 1
 

Stage 2 
 

Stage 3 

 

Stage 4 
The initial male part or plug was manufactured in solid timber on a lathe and assembled with flanges ready for moulding. The shape was made convex to assist in finishing and fairing as concave surfaces are significantly harder to fair. As the plug would not be sufficiently stable to produce parts on any long-term basis a Master Part is manufactured from the plug. From or on this Master Part we then manufactured our mould. Each stage must be undertaken with understanding of the materials used and the process. Shrinkage, heat distortion and pre release can adversely affect the finished result. The materials used are low shrink, high quality tooling products and between each stage the parts are faired, release agents applied and all are allowed to stabilise between operations. 
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