How to rejuvenate a colour contrast penetrant

In the '60s a British military aircraft engines manufacturer subcontracted some business to a French manufacturer.

In these old times some military engines casings were made of magnesium alloys castings.

To avoid any discrepancy in control a colour contrast penetrant, so-called "Bristol-type", had been standardised in the Bristol (UK) plant - hence the name! - and in the French plant.

Penetrant Testing: a badly-designed drying oven

A short "Oldies but Goodies" story, again about a faulty design. It dates back to the early seventies … yes, an old story! A story for veterans, right.

A well-known French manufacturer of valves for car, truck, even ship engines had bought a complete penetrant testing line. The valves were inspected using a water-washable fluorescent penetrant and a dry developer, listed in the QPL (Qualified Products List) of the American Military Specification MIL-I-25135 C (ASG)(*) which was in force at that time.

Diving in fluorescent penetrant for special effects (FX)

Once again, a "veteran's" story! But as always (at least, we hope so!) the lesson taken from a TRUE story may be useful to others in similar situations - though we think this one will never occur again !!

On a Friday, ca 4 pm, the end of a week in this company which manufactures parts for aircraft. In the penetrant line area, everything is idle, inspectors are filling in the last forms of the week. A half-hour later, time for the week-end!

The auditor and the units

The following story is true - as all the examples we give are!

Do our American friends have a feeling against SI units (units used in the Système International, the International System of units)? (*)

We could think so, when we read the American specifications ... and when we see how sometimes they "understand" the powers of 10. They are prone to use a capital M for "micro" (10^-6) when in the SI a capital M comes for "mega" (10⁶). That means a trillion times (10¹²) less or more!!!