Citroën technical note: adoption of VF10 brake fluid (1 December 1955)

In this document

This "Méth. Tech." (technical methods) sheet is addressed by Magès to Mr. Malleret, with copies to Messrs. Cadiou, Clerc, Ingueneau and Pompon p. 129. It bears the handwritten date "1-12-55" and concerns the "TT" vehicle p. 129.

The request

Following "Mr. Clerc's note No. 20" and a "Test No. 222905 from the Central Lab", the note requests that the brake control fluid for all vehicles, except the DS, should henceforth be Citroën-manufactured VF10 fluid, and that purchases of "ready-made" fluid from outside sources should be stopped p. 129.

The economic calculation

The document details the customer price (1955 base) of a litre of VF10 manufactured by Citroën:

Compared to a price of 348 Fr for fluid purchased from outside, the announced saving is 134 Fr per litre, i.e. 38.6% p. 129. A second table, entitled "Savings expected per litre" (the word "car" having been crossed out and corrected to "litre"), only provides information for the "Total" box at 134 Fr, with the other columns (material input, finished weights, time, cutting tools...) remaining as dashes p. 129.

The bottom of the form indicates the file "43-4 (14)", the manager "Daumain" and a reference "Pr. A No. 669-TT" dated 1-12-55 p. 129.

Context

The VF10 brake fluid, known in Citroën's history, has the particularity of being incompatible with the high-pressure hydraulic circuit LHS and then LHM of the DS, which explains in a general way, for any reader familiar with the brand, the systematic exclusion of this model in this type of note — an exclusion that the document itself confirms in its own text, without the need to add any further technical explanation.

The 1950s were, at Citroën as elsewhere in the French automotive industry, a period of rationalisation of production costs, with the internalisation of the manufacture of parts previously purchased from outside being a common practice to reduce cost prices. This note is part of Magès's schedule recalled by his autobiographical notes: having joined Citroën in August 1925, he was then, in 1955, deputy manager at the Super-Control after having worked in the design office (draft letter to Mr. Sarre) — one year after the test of the 15-Six H and a few months before the presentation of the DS on 6 October 1955.

Archivist's perspective

This document illustrates a lesser-known aspect of Magès's work: beyond the invention of the hydropneumatic suspension, he also intervened, as a technical manager, on very concrete industrial rationalisation issues, here the choice of a brake fluid p. 129.

The precision of the date — "1-12-55" — allows this note to be situated in the production schedule of the year 1955, less than two months after the presentation of the DS on 6 October 1955, which explains the particular attention paid to the exception of this model.

This piece belongs to the same file as the Folder "Theoretical study – hydropneumatic suspension 1943/44" and the Summary of folder 41-59, which gather the technical developments linked to the DS; it bears witness to the diversity of subjects treated in Magès's archives, between breakthrough invention and daily industrial management.