About Harboro Rubber Engineering in Rubber      Contents      Introduction      Uses of Rubber      Processing Rubber      Designing With Rubber          Designing For Minimum Costs          Producing A Specification          Prototyping          Designing Components          Tooling Design          Cost          Colour          Surface Finish          Materials          Tolerances          Quality      Selecting / Specifying Rubber      Quality In Rubber      Rubber Directory      Health & Safety      Measuring Properties      Glossary of Terms      Request A Copy Contact Information

Tolerances The finer the tolerances required, the more costly the part. M2 is the normal tolerance band for industrial parts. Bear in mind that rubber is elastic and easily accomodates variation. M1 tolerances require the moulding process to be designed around dimensions for example by reducing the number of cavities or reducing injection speeds and will usually mean increase costs. Tolerances for moulded products to ISO 3302 1995 (BS 3734) Table classes M1 (Precision) and M2 (Commercial). F = Fixed dimensions (across cavity area) C = Closure dimensions (dimensions affected by split lines) (Dimensions in mm)