Hi RevDoc,
Seems to be a labor of love!
Had a quick look at your translation and will revert for a more leisurely read later. My gunmaking French is not very fluent, so I’m in no position to play the professor.....
A couple of points – “barrel makers” is probably a more accurate translation of “Canoniers”
I would prefer “twists” for spires, rather than “turns”
The family name is Malherbe de Goffontaine and not Goffontaine or Malherbe Goffontaine. The “de” usually indicates a minor nobility/landowning background way back in the past. (Most French/Belgian surnames derive from localities; Goffontaine is a village very close to Liege.)
The translation is a bit off in places, e.g. Ils soudent cinq centimètres de spires à la fois puis réchauffent les spires suivantes is translated as “They weld five centimeters of turns at a time and then turns the heat below.” This should be “They weld five centimetres of turns at a time and then reheat the following twists/turns.”

On the words you asked about, I've no context but fwiw
Effet de moire - I suggest that an accent is missing from the e of moiré ; it is a term frequently used in textiles, a wavy effect, usually seen on silk.
Vilebrequin - A Google search shows that it is associated with crankshaft steel, seems like a process?
Corroie – is this a typo? In car engine terms Courroie is a fanbelt or any flexible loop used for transferring power.
derochment la trancha?? Possibly another typo? Tranche is a slice and derocher is probably based on roche = rock. With a “c” inserted Decrocher is the verb to “unhook” e.g. to pick up a phone is to decrocher

Rs
K.
See that Larry B beat me to it!

Last edited by Kerryman; 05/12/09 08:45 AM.