Armour Plate

[Page]

How do you/ can you test plate to know if it is actual armour or just a mild steel reproduction?

[Adrian Barrell]

You would have to have a hardness test carried out. This essentially consists of pressing a point or ball into the surface and measuring the force required. The problem is that different types of armour have widely differing surface hardness levels so you would need to have a known level to compare it to to be absolutely sure.

 

Of course if it came out as harder than mild steel, you would at least know it wasn't ms and therefore must be armour!

[TooTallMike]

If there's a hidden area you can drill, try and make a hole in it. The armour on the body of one of our halftrack melted even titanium-tipped drill bits!

 

- Mike

[Adrian Barrell]

That would be, if on a White halftrack, face hardened armour. You can just about drill it from the soft, inside face. Shermans are homogenous armour and you can drill it quite easily with HSS bits. In fact, it was noted at the time that pre-1943 US armour was a little bit too soft. Armour, yes but not hard.

 

As I said, there is armour and there is armour!

[TooTallMike]

That would be, if on a White halftrack, face hardened armour. You can just about drill it from the soft, inside face. Shermans are homogenous armour and you can drill it quite easily with HSS bits. In fact, it was noted at the time that pre-1943 US armour was a little bit too soft. Armour, yes but not hard.

 

As I said, there is armour and there is armour!

It's an International, but probably the same principle. I didn't know that about the Shermans. Interesting.

- Mike

[Adrian Barrell]

Internationals are homogenous but 5/16" against the Whites 1/4". Obviously better quality than the Shermans! The other point is, the higher the manganese content, the more likely it is to work harden.