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Advisory Panel
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12-01-2016 02:16 PM
# ADS
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Advisory Panel
Ours didn't get out into general circulation. Parts for the most part weren't released. Apparently Blake Stevens bought all the parts LB had as scrap and then when Diemaco put the FNs into war reserve, he sold them all his spares at individual value. Still, those didn't make the street. Now they all went to the smelter so there go your buttplates. The odd one shows up on CGN but that's it.
Tri walls of FN C1/C2 and C1 SMG spares went to numrich and sarco.
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Advisory Panel
That's right, they did. I remember now that lots of stuff seemed to be available a bit ago. Wonder if any is left?
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Legacy Member
Regarding the "S" on the Oz Body Locking Catch:
WPN D 253 Para 45:
....During an unknown period of time, phosphated Locking Catch springs may have been fitted to the L1A1 and L2A1 Rifles. If the spring has been phosphated, its life has been reduced.The faulty spring is easily identifiable as it has a black phosphate coating.The serviceable spring has a bright, cold rolled finish. Weapons that have been inspected for this fault are to have the letter "S" (3mm high letter) stamped on the locking catch lever( prior to the reconditioning of the weapon) to denote the weapon has been inspected, as shown in Fig. 14.
Comment: The life of the "black" spring was "reduced" because, in order to successfully phosphate it, first it had to be grit-blasted, creating in the process, instant stress risers in the spring wire.
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Thank You to Bruce_in_Oz For This Useful Post:
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Contributing Member
Thanks for the info Bruce, another question answered. Very few go unanswered on Milsurps thanks to our knowledgeable membership..
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Legacy Member
When I worked at certain weapons manufacturers post Military Service.
One of the many 'Products' we made, obviously had springs in/on them.
It is absolutely correct, that when shot blasting springs. They become very brittle & have the potential to fracture quite quickly.
This was over come by a process called 'De-Embritlling. Where springs after blasting & phosphating. Were put in an oven for 30 mins afterwards at a specified temperature.
It was not too hot, or the springs would have lost their Temper (Springiness)
This overcame the springs previous condition of being Brittle. & all springs worked very well, in the whole range of products that we manufactured.
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Legacy Member
Similarly, all "stressed" parts that are "hard-chromed" are baked at a moderate temperature for the same reason.
During the plating process, Hydrogen migrates from the acid bath into the steel. its presence plays merry hell with the "skin" of the steel substrate, i.e., Hydrogen Embrittlement. Baking the components at a relatively low temperature for several hours cooks the Hydrogen out.
The trick with Phosphating is that the process doesn't work very well unless the surface of the metal (steel) has been "activated". The quickest and most effective way to do this is to "blast" it with an abrasive grit; the harder the surface, the harder / "sharper" the grit required. Basically this "micro-deforms" the surface and shuffles molecules around. That is also why the best Phosphating is achieved when the article is fresh out of the blasting box, with "distressed" surface molecules, and goes straight into the "bath".
This may be why one traditional spring finish was "blacking", by the same "blazing off" of a quench oil, as was done to many small Lee Enfield parts.
"Micro-deforming" a spring with a good grit-blast is a sure way to form tiny little "pits" that become stress risers. Blasting with a hard steel shot as opposed to garnet grit, will certainly create a lot less potential for these stress risers to occur.
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Thank You to Bruce_in_Oz For This Useful Post:
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Advisory Panel
Originally Posted by
tankhunter
when shot blasting springs. They become very brittle & have the potential to fracture quite quickly.
That was something that was u nknown to us many years ago when we did bead blasting and blue or parkerize. I wonder how many failures have resulted from our past work?
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De-embrittling...... That's a word and process I haven't heard of for many years
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Thank You to Peter Laidler For This Useful Post: