Reproduction UC Track availability?

[Philliphastings]

Some years ago an associate showed me some steel moulds for Australian track which he had squirrelled away. from memory they were steel and box shaped with an upper and lower half which bore the impression of a single track link at a time.

I know very little about metal casting other than lead so were these the masters for making the sand moulds or something?

I recall a lot of discussion about having track links re made but the owner wasn't interested unless there was a quick buck to be made. Perhaps these days he could be persuaded to do something.

Cheers

Phill

[cantankrs]

Originally Posted by Philliphastings

Some years ago an associate showed me some steel moulds for Australian track which he had squirrelled away. from memory they were steel and box shaped with an upper and lower half which bore the impression of a single track link at a time.

Hi Phill,

Interesting info. Since Wayne's pics show aluminium patterns that already have the little markings (mentioned and/or displayed by Ron and others earlier in this thread) cast into them, it indicates that they were cast from a pattern higher up the evolutionary tree so-to-speak. Presumably even aluminium patterns would be worn away from repeated use (ramming molding sand against them) then they would need to be replaced once certain tolerances were exceeded. So it's likely that they were poured using aluminium into a metal mold of a higher melting point - in this case steel or possibly cast iron. Since the marking plates wouldn't have been screwed to a (female) mold it indicates that the mold you describe was cast from a master pattern even higher up the chain.

During the war in aircraft plants, the hammers and dies bolted into Drop Hammers (for stamping aluminium alloy sheet obviously) were poured from lead for one and an alloy of lead and something else - tin or zinc that bore a tradename I can't think of at present. The reason for the two was that one had a slightly lower melting point and could be poured into the other to create the reverse shape without damaging it. It was a relatively quick method and reasonably easy metals to work. It lasted long enough and then melt the stuff down again and pour out a new hammer and die.

Perhaps Wayne could send thru some pics of the other bits he mentioned?

Regards

Alex

[matt_mcleod]

Hello gents,
Please permit me a brief introduction in my first post. I am a chartered mechanical engineer in Australia and hold a financial interest in an engineering shop in Ballarat, Victoria. We complete engineering and machine shop jobbing for automotive, transport, agriculture and manufacturing businesses. We have a keen interest in keeping old machines running, and personally, my interest is in Australian cars from the 50's.

A colleague who is restoring his own Universal Carrier alerted me to this thread just after it started. My business has contacts in metallurgy, pattern making and NC machining so we decided to invest a few hours to see whether it might be economical to manufacture repro UC track. I also spent 12 years working for Caterpillar so I have a reasonable knowledge of the engineering of tracked machines.

We secured one unused link and contacted our pattern maker. His birthdate pre-dates Universal Carriers and his knowledge is encyclopedic so I greatly respect his professional opinion. We have a copy of Nigel Watson's UC reference text describing the use of manganese steels, cast steels and malleable cast irons. Our pattern maker assures me these materials were used because they were the best technology available at the time. Based on the low utilization of restored carriers (ie who would do 100 miles in one year in their carrier?), his suggestion is a tweaked 500/7 ductile iron, which will suit the job and is relatively cheap. I don't believe there is any good technical reason for attempting to replicate the original material as this will only increase the price.

His iron foundry work is completed in China as he has not located a foundry in Australia able to compete. Our pattern maker has his own business manufacturing brake components for automotive and earthmoving equipment, and has assured us of a first class casting. With his own business and reputation on the line, I have to believe him. The pattern is quite complex, as has been discussed in detail above, and accounting for shrinkage with the given material is where the skill of our Chinese friends will come into play. We are investigating a sample run and trying to keep this as cheap as possible.

We are attempting to determine an ex-works price from our workshop in Australia for assembled field service track sections to suit a single machine (obviously to make manual handling the link sections safer when they arrive at its destination). Tooling costs have already been supplied from China, and are in the vicinity of US$2500, so this is not a cheap proposition. I have piece prices from one supplier (pre-drilled for the pins) ex works in China so I need to work out shipping and duties over the next couple of days.

I do need some help from the forum, however. The track pins, according to Mr Watson, are hardened along most of their length to permit the free end to be peened. I have one pin, but the end was ground off to free it from a track. What is the free length of a new pin, from one end to another? I have estimated 10" under the domed head to the plain end, based on the track link being 9.5" wide and allowing for peening or split pinning. Any thoughts from the forum?

Anyway, we have plenty still to do to determine a price, but would be interested in comments from the forum members. Obviously the more interest, the cheaper the parts will be, as we would amortize the tooling, shipping and duties over the entire run. I'm thinking about enough links and pins to supply new track assemblies for 20 machines, on the assumption there are at least 20 guys somewhere around the world who want (need?) new tracks for their carriers.

Oh, and these would be English pattern links. I understand the Aussie links were different due to a wider bogie wheel.

Here is a link to our website, you can see our equipment and local engineering and machine shop pricing, plus links to our contact details and LinkedIn profiles.

Regards,
Matt McLeod

[Lynn Eades]

The Aussie track uses a shorter straight plain pin. At the inner end, the hole is smaller. This allows the pin to be punched out, whilst being retained. The other end has a recess with a groove in it. This end is lead plugged. Punching the lead plug in, expands the plug into the groove, thus retaining the pin. The lead is soft enough to fail, when the pin is punched from the inner end.
With English or Canadian track(essentially the same specs) the pins are as per your description. The track sections are assembled into 21 link sections, and joined with pins, that are located with a washer, and split pin I have a number of these pins, and can supply a sample if you wish.
Be aware that the track has quite a tolerance between the links, and requires this side clearence, to allow the track to displace sideways, allowing the machine to turn. The double bogie assembly moves 3/8" each way from centre. I would estimate that the track would need to achieve this over about 16 links (the number of links between the front bogie, and the 2nd bogie wheel)

[matt_mcleod]

Hi Mr Eades,
Many thanks for the extra detail. Yes, I was aware you steer a UC via the bogie, not like an earthmoving machine which is turned via track speed differential.

We'll work on the assumption that the sample link we used for the pattern will give us the correct clearances to permit the UC to turn, but will verify with samples, if the project goes ahead.

I'd appreciate a sample, but some measurements with a vernier caliper would suffice if you can help. Otherwise, I'd be he happy to purchase a pin/washer/split pin from you to ensure we have accurate basis for any reproduction. Let me know what works best for you.

Thanks again,
Matt.

[Lynn Eades]

The nominal length of the pin, from the shoulder under the head is 250mm (of 22 pins, they vary from 248mm to 253mm.
Shoulder to centre of split pin hole is 246mm to 247mm.
I have one pin wth a change of colour at the 241mm mark.
The diameters vary around 0.4375" (7/16")
Some are marked "L" (maybe Leys U.K.) others are marked "V.P 1943",one is "N 2/3, and others are plain.
Some are black, while others are bright steel.
Anything else just ask.
Oh, and Matt, Red, Lynn, or Bluebell will do fine.
,

[Philliphastings]

Hello Matt and welcome to the forum. What you are proposing is indeed exciting news for non Australian Carrier restorers...

Cheers

Phill