My Bren MKI

[Woodsy]

I also understand that the carriers built by GM NZ were NOT built from "armour" plate steel and were essentially "trials" or training vehicles.

Yes, they were made in mild steel for NZ training only, allowing the properly armoured ones to be used overseas.

[Surpmil]

I know someone with quite a stock of CMP trucks and parts, if anyone wants a ready-made collection.

I was going to ask about the Pyrenes as well. Might well be true about turning into an even worse poison gas. Carburetor cleaner turns into phosgene if heated. The tiniest whiff will muck you up permanently.

[Peter Laidler]

Maybe a chemist forumer can elaborate on the fire extinguisher/carbon tetrachloride filling myth - if it is indeed a myth. I have been using CTC as a chemical cleaner for more years than I can remember and certainly nothing else can beat it for separating cemented lens quickly. Alas, you can't get it now so I still distil what I have left to purify it. But suffice iut to say, I am still alive.........

[Surpmil]

I consulted the oracle: Carbon tetrachloride - Wikipedia, the free encyclopedia

The old Pyrene extinguisher gets honourable mention: seems 'Carbon-Tet' becomes phosgene when heated, so I guess that tells us what is in carb cleaner.

[tankhunter]

As a slight aside from what Peter has written on the Subject of Phosgene.

Back in the day, before Deact's were available to us. I was asked to manufacture a replica Vickers Watercooled MG. To make the more complicated earlier variant with the fluted waterjacket. I obtained an old corrugated steel dustbin. Which had strengthening flutes all the way around the main body. I'm SURE you can picture these in your minds eye?

Well, I duly cut out a section to enable Me to make the jacket of the correct diameter.
The problem cam when I began to seam weld it into cylindrical form!.....
The fumes given off from the plating on the outside I believe were Toxic in the extreme!
Even though I was welding outside, the first intake of 'normal' breathing. Made Me stop IMEDIATELY!.....JESUS! it was just like someone had thrust a Knitting needle into my lungs! I didn't try THAT again! & got a specialist welder who used breathing to complete the seam weld. And also weld in a cap at either end.

So, be aware, be VERY Aware of heat & differing metals. It never entered my head on this topic. As I assumed (NEVER Assume ANYTHING!) that I would manage as I was working out in the open!....................

[stencollector]

As a slight aside from what Peter has written on the Subject of Phosgene.........an old corrugated steel dustbin........The fumes given off from the plating on the outside I believe were Toxic in the extreme!

Galvanised metal is very dangerous to weld.......ranks right up there with the Carbon Tet.

Speaking of Carbon Tet, I have a bit of a collection of those old extinguishers. The DND marked ones are the basis of my collection, and they can be found with DND army, DND, and a host of other variations. I even have British made ones that are DND embossed. Some still have the carbon tet in them, but I have no intent of ever using them on a fire. I'll normally have a normal dry chem extinguisher buried away in my old milsurp vehicles...the brass ones are just for display. They can be filled with water to work, but that is not a good idea in this climate as they will freeze and split in the winter.

[Korn]

The chlorinated brake cleaner is what is should be avoided. The phosgene gas forms when welding a part cleaned with the brake cleaner, the argon used for shielding gas combines with the heated brake cleaner. Like it was stated above, even a small amount of exposure can be very bad. We use acetone to clean parts to be welded at work.

[tankhunter]

[QUOTE=stencollector;286559]Galvanised metal is very dangerous to weld.......ranks right up there with the Carbon Tet.

Yep, I found out the HARD Way!.....................