Blog

Notes from the workshop.

Short, useful writing on elastomer materials, aerospace specifications, manufacturing processes and the quality practices behind them.

Semi-automated bagging and heat-sealing machine sealing polythene bags of moulded elastomer O-rings in a rubber components workshop

Featured · Quality

Packaging is part of the specification: bagging rubber parts to BS 3F 69:1979

Why the bag a seal arrives in matters as much as the compound it is moulded from, what BS 3F 69:1979 asks of polythene packaging for aircraft parts, and how a semi-automated bagging line keeps identity attached to every part.

3 Aug 2026 · 7 min read

Aerospace

Selecting aerospace O-rings: specifications, materials and sizing

How AMS-R-25988, AMS-P-5315 and AMS 7276 differ in service, and the sizing and groove decisions that decide whether an aerospace O-ring seals for its design life.

28 Jul 2026 · 9 min

Colour-coded elastomer O-rings arranged on a workshop bench

Materials

Choosing the right elastomer: a designer's short guide

A pragmatic tour through NBR, EPDM, silicone, FKM and FFKM — and the questions worth asking before you pick.

15 Jun 2026 · 7 min

Precision metrology instruments and moulded rubber sealing components on a granite inspection bench

Quality

AS9100D: what the certificate on our wall actually means

Aerospace quality is more than a badge. Here is what an AS9100D audit looks at, and why every customer benefits.

28 May 2026 · 6 min

Detail of a jet engine assembly showing seals in the fuel and lubrication path

Aerospace

AMS-R-25988 and MIL-DTL-25988 demystified

The specs that keep appearing on airframe drawings — what they cover, and how to source to them.

14 May 2026 · 6 min

Hot rubber component being lifted from a compression moulding press

Manufacturing

Compression, transfer or injection moulding: choosing the right process

The three main rubber moulding processes, and where each earns its keep.

30 Apr 2026 · 7 min

Cross-section of a bonded rubber-to-metal component on a workshop bench

Manufacturing

Rubber-to-metal bonding: how it works, and where it fails

Primers, adhesives, surface prep and the reasons bonded assemblies sometimes debond in service.

16 Apr 2026 · 6 min

Satellite being prepared in a clean assembly hall

Aerospace

Low-outgassing elastomers for space applications

TML, CVCM and RML — the numbers that decide whether a compound is fit for vacuum service.

2 Apr 2026 · 6 min

Engineering drawing, calipers and a moulded rubber sample on a workshop desk

Design

Seal design: five pitfalls we see on incoming drawings

The small drawing decisions that lead to seals leaking in service — and how to avoid them.

19 Mar 2026 · 6 min

CMM probe measuring a moulded component on a granite surface plate

Quality

First-article inspection: what to expect from a new supplier

FAIR, AS9102 and the paperwork that accompanies a first production run.

5 Mar 2026 · 6 min

Coated elastomer shaft seals on a stainless steel bench

Manufacturing

Coatings, primers and surface treatments for elastomer components

PTFE coatings, low-friction treatments, adhesive systems — and why they usually earn their cost.

19 Feb 2026 · 6 min

Raw compound ingredients and rubber test sheets on a laboratory bench

Materials

REACH, RoHS and elastomer compliance: a supplier's view

What the material declarations on your incoming inspection actually need to contain.

5 Feb 2026 · 5 min