Hi,

I'm working on a Royal Marines Centaur tank for a campaign and had a question regarding British tank treads.

I think I've read somewhere that steel used in construction of British tanks and ships contained a large % of magnesium, which if I remember from high school chem class rusts to a dull grey. I usually paint tank treads a medium brown to represent light oxidization. But on the Centaur do you think I would be better off painting them a dull grey instead?

Again I might be 100% off base here, the information I'm working from is entirely from memory so there's a good chance I'm remembering it wrong.

Thanks for your advice

Jeff

Well, you're kinda wrong, I'm afraid, on several counts.

Some tracks (British or otherwise) did include some small amounts of magnesium in the alloy. They also included a higher amount of molybdenum and vanadium. Depending upon exactly which tracks you're loking at and exactly which alloy they used, these tracks didn't so much "rust" grey, but formed a quick grey surface coating and then didn't rust further (the Valentine at CFB Borden has these tracks and shows no sign of corrosion after nearly 70 years in the open.) I will grant that, technically, that initial grey layer is a form of corrosion, but much like the dull surface on a piece of aluminum, it then protects the metal beneith from further corrosion.

Armour does _not_ include any significant amount of magnesium and rusts red/orange like any other non-stainless steel.

Tracks, unless left unused, quickly burnish to a brushed metal appearance after only a couple of minutes running across any surface. If running on roads, the tips of the tracks in contact are quite bright and over open ground, even in damp soil, the entire working face of the track is also quite bright. On the back side of the track the areas contaced by the road whees (even rubber tired ones), the sprockets and things like the guide teeth and track pins are all quite bright. The only place where some rust might accumulate is the untouched portions of the back surface and, even then, if the tank has been operating in sand or deep loam, the material that builds up behind the contact surface and then just flows around there will burnish rust off those surfaces quickly as well.

If you take a look at a local bulldozer, pretty much the entire inner & outer surfaces of the track are burnished bright all the time. If left for a day or so there is a film of bright orange rust that goes away quickly when the vehicle is used again.

I have pictures of Rams at Meaford & Borden during the war and in the sandy soil up there the T54 Sherman track they use are bunished quite bright all over.

Now, brown dirt can pack itself into crevasses of the tracks so brown is appropriate there, and mudddy tracks will ahve brown mud over the metal, but the metal track surface of any tank in regular use should really be burnished steel rather than any kind of rust colour.

HTH

Paul

Thanks, just the clarification I was looking for.

Cheers

Jeff

The metal used in track alloys is manganese, not magnesium. Sound similar, very different metals.

Manganese alloy track would rust, but the rust was darker, almost violet. Humbrol 173 track colour was the closest match I've seen, lightened naturally to depict dirt and dust. The artist's pigment umber has some manganese in it.

It depends upon the specific alloy. Most tank track does have manganese, and does rust pretty normally, but the alloy in the Valentine tracks at Borden has no traces of rust whatsoever. I was really surprised, to be sure, but there it is.

Paul