Hi Everyone,
Just to renew this thread , my experience last week on bluing Challenger 2 tracks from brand new 2019 Version 6 tank.
Firstly as siegfried said above the product to use is Birchwood Casey-Aluminium Black .
The Heng Long tracks are totally non ferrous, the only reason a magnet sticks to the tracks slightly when placed over several links is the attraction to the steel track pins!!
I used 2 bottles, 1 for each track with some left over. Use fresh bottle for each track.
This is NOT a quick job as described above on the tracks for a M1 or C2 as opposed to the WW 2 tracks most people in this thread did above due to the shape of the track plates!
METHOD
I cleaned off tracks with rubbing alcohol and let dry.
Wear gloves and glasses, this is acidic!!!... but looks like windex.
Pour 1 bottle into a small bowl with circular bottom shape to get sufficient depth of liquid.
Hold tracks open like a necklace in an open loop and slowly pass bottom of loop thru the liquid, working your way around slowly, I did it several times.
I also used a brush with 1 hand on INSIDE of track as I passed it thru the liquid to force it into the square holes where the rubber track pads would go on the more expensive tracks with this feature.
I found this necessary (using brush) after my first attempt as despite tracks being completely submerged a number of these square areas were still metal colour as liquid did not touch them!! (due surface tension of liquid forming a bubble even though this was not visually apparent!!)
MODERN TRACKS- the other problem area on these tracks which was not apparent until removing from liquid and then immersing and washing in water after 2 to 3 min to nuetralize the acid was this-
Due to the surface tension of the liquid MANY of the small holes between the “track blocks” on each track link was also untouched and still metal colour.
I had to use a small brush to put a blob of liquid over each hole then work it into holes with wooden toothpicks moving back and forth in the holes. This took a long damn time!!
Once done all that rinsed off thoroughly and let dry in hot sun ( summer here in Australia)
Next step- I told you this wasnt a quick 20 min job!!
It took me several hours total!!
Rub off the inside and outside flat surfaces thoroughly to get off the loose oxide powder with a dry microfibre type cloth.
Then get a dry toothbrush and holding each link gap open between each track link brush a few times to remove powder build up in there too.
Then wash off all oxide dust , dry again and you are done !!
The results look Excellent!!
But I am worried that any running on pavers or concrete will scratch off the black oxide revealing the bright shiny metal underneath which may look ok on WW 2 tracks but not on modern ones that have rubber track block shape squares!!
I don't want to spray on a sealer coat as this will scratch off too anyway and then when needing to re blue with a brush over the scratches on the outer blocks there will be a layer of sealer paint over everything contaminating the surface.
Hope this helps anyone wanting to blue their new tracks!! Cheers All!!
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