[dreadnought1]

Having followed this thread for some time,I have decided to enter the debate.

The remanufacture of new track is entirely possible and can be done relatively cheaply provided you know how the process works.The following applys to Aust made track but can be applied to British track as well.

Over 20 years ago the West Australian Government State Engineering works was closed and a huge collection of machinery was sold off.As the works made carriers during WW2,the pattern store contained the majority of the patterns required to cast track.This store was supposed to be saved for historical reasons but the bean counters got in ahead of every one else and the contents of the pattern store were burnt.

I was able to save several complete sets of patterns,the central core print posted by Wayne(this is an incomplete unit which i gave him) is an example.

Background - The SEW had installed in an annexe to the main machine shop
six large cupola furnaces 8ft in dia x 25 ft or so in height.This enabled 20-40 tons of malliable cast iron to be available from any of the cupolas for a production run pour.

Cope and Drag-founding term for moulds , First operation -manufacture of cores -Cast iron moulds in pairs into which a green sand and molassis?
mixture was forced in then stove dried.This gives a lumpy strip of hard foundry sand which is then inserted into the hollow section of the track moulds where the track pins go.

The lower moulding box has a aluminium plate with four track openings which allow the central core to pass through.The box is of softwood construction and has a plaster of paris matrix which supports the central core.This matrix is painted with shellac to slow down moisture penetration.

The central core(See Waynes photos) is made up of four track units cast in aluminium-over size to allow for contraction when pouring cast iron.The track unit patterns are affixed to a bronze frame which forms the risers (channel for molten metal)
On side A the track grip is formed along with half of the support tube for the track pins.You will note the bars sticking out of the support tubes-this is to accomadate the core print which casts the holes.

Side B sticks up and when rammed with sand forms the inner part of the track horns and inner part of the track.Two separate insert cores slip into a squre recess formed when side B is rammed and these form the outer face of the track horns.The completed unit of mold A and B are separated,the pin cores are inserted in the appropriate hollows within the moulds.All taperd plugs are removed from the face of one of the moulds-allows metal to be poured into the centre , the halves are dusted with a release agent , the cope and drag is closed and sent to the foundy ready for the main metal pour.

OK folks,that how it is done , to do your own you need a pin core box,an outer horn core box,a base mould,a centre core mould and last but not least a coke fired cupola funace and lots of cast iron scrap.

I will post some photos of the surviving patterns in due course .

Cheers.