This guide relates to Miles Platts catalogue items.
Tolerances are in line with DIN16742 and are dependent upon a number of factors.
Factors affecting tolerances,
- The polymer selection and its’ glass content
- The tolerance band is appropriate to the nominal dimension
- The temperature & humidity of parts being measured
- Glass filled engineering polymers are anisotropic and shrink at different rates across different axis
- Where the tool splits and whether the dimension is formed by a solid core or a moving part of the tool
- Which tolerance group being applied which is calculated from a number of factors.
- Miles Platts catalogue items generally fall into TG6 tolerance group
Other considerations for tolerance guidelines,
- Measurement points may have draft applied and therefore will vary across a surface
- Consideration should be given to radii on edges and internal corners (A)
- Glass filled engineering polymer distorts- unsupported features will toe inwards (A1)
DIN16742:2013-10 Table 2 extract- limit dimensions for nominal size ranges (TG6, non-tool specific dimensions) .
Tolerance limit dimensions are intended for linear dimensions only.
Limit dimensions for nominal size ranges (mm)
Tolerance
Group |
1 - 3 |
>3 - 6 |
>6 - 10 |
>10 - 18 |
>18 - 30 |
>30 - 50 |
>50 - 80 |
>80 - 120 |
>120 - 250 |
| TG6 |
± 0.12 |
±0.18 |
±0.22 |
±0.26 |
±0.31 |
±0.37 |
±0.57 |
±0.80 |
±1.05 |
