NEWS VACANCIES DOWNLOADS CONTACT US Sizing and Tolerances Sizing and Tolerances depend on the geometry of each part, but the following tolerances are suggested as a guide to designers. Lengths including hole diameters, held to: mm inch Section Tolerance Section Tolerance 0 - 15 ±0.08 0.0 - 0.6 ±0.003 15 - 25 ±0.13 0.6 - 1.0 ±0.003 25 - 50 ±0.25 1.0 - 2.0 ±0.010 50 - 75 ±0.37 2.0 - 3.0 ±0.015 75 - 100 ±0.50 3.0 - 4.0 ±0.020 100 - 125 ±0.60 4.0 - 5.0 ±0.025 125 - 250 ±1.00 5.0 - 10.0 ±0.040 Flatness Generally held to ±0.13mm (0.005") per 25mm (1.00") square. Straightness Generally held to ±0.1mm (0.004") max per linear 25mm (1.00"). Squareness and Angularity ±0.5 degree Note: Angular tolerances are affected by irregular geometries. When tolerancing, use of a central feature as a datum may allow detail to be cast that would otherwise carry too large a tolerance. Where a mechanical interface feature is required on a surface, it helps to use the centre of the feature as a datum. Wall Sections Constant section thin walls are preferred but large changes of section can be accommodated through critical analysis of the component design and special tooling design features. Size (cubed) Suggested Wall Thickness up to 10mm (0.4") 0.2mm - 1.0mm (0.008" - 0.04") 25mm (1.0") 0.5mm - 1.5mm (0.02" - 0.06") 75mm (3.0") 1.0mm - 3.0mm (0.04" - 0.12") 100mm (4.0") 1.5mm - 3.0mm (0.06" - 0.12") above 100mm (4.0") 2.0mm (0.08") upwards Cast example of 1mm (0.040") wall thickness throughout Cast example of thick and thin wall sections Cast example incorporating ribs to improve flatness and rigidity Wall thickness and flatness over large surfaces are better controlled if through-holes and ribs are incorporated in the design. Wall Section Tolerances mm inch Section Tolerance Section Tolerance up to 0.5 ±0.10 up to 0.020 ±0.004 0.5 - 1.0 ±0.15 0.020 - 0.040 ±0.006 1.0 - 2.0 ±0.20 0.040 - 0.080 ±0.008 2.0 - 4.0 ±0.25 0.080 - 0.160 ±0.010 4.0 - 8.0 ±0.30 0.160 - 0.320 ±0.012 Cast example incorporating holes to improve flatness and reduce weight Sylatech Design Guide DOWNLOAD THE DESIGN GUIDE Get in touch! Our sales team will be happy to discuss your requirements. CONTACT US TODAY QUICK LINKS About Us Contact Us Terms & Conditions STAY INFORMED By submitting my information I consent to the use of my personal information in accordance with the Privacy Statement and acknowledge that I have read and accepted this. CONTACT US Sylatech Limited, Kirkdale Road, Kirkbymoorside, North Yorkshire, YO62 6PX Phone: +44 (0) 1751 432 355 Email: engineer@sylatech.com © Copyright 2021 Ace Digital Design | All Rights Reserved | Articles Twitter LinkedIn Facebook Instagram