Reproduction UC Track availability?

[ron]

Alex just one more, this track sat in a shed for 53 years befor I got it

[ron]

Hi Ian and thanks for posting that information regarding the track tests,they should make for very interesting reading, thanks mate Ron

[RichardT10829]

Ron, are those shots of Australian pattern track or Can/Brit ? i have had a look at a couple of links in my pile and i cant see any maker marks or proof stamps, i will give them a clean up and see if i can find some.

[cantankrs]

Wayne has kindly sent thru some pics.

The tapered block things beside the guide horns are core prints to receive sand cores to form the recess on the outsides of the horns.

Hi Alex,
Main track link section is alloy, centre section is bronze and the pins are steel.
Wayne

Alex

[cantankrs]

Had a think about Wayne's pics. I've never cast metal apart from lead in my life but I'm intending giving it a go so I've gathered and read a fair bit about it. I mentioned the horn core prints earlier and I've circled in yellow all the visible core prints in this pic. Core prints are corresponding depressions in the sand in which a baked sand core is placed. The core is longer than the void it needs to bridge or fit so that it gets held in place by its extremities. All the horizontal bits of steel rod in this case will be replaced with sand cores the same length and diameter after the pattern is removed and before the drag and cope are fitted back together. Thus sand against sand becomes the mold, but any cavity receives metal from the pour.

The pink oval is the area of the feed runners (the horizontal bars). The vertical rounded top parts may be risers or feeders - I'm not sure which - perhaps they're both. Comparison of these pattern vs Ron's actual track link pics shows where the runners were cut off the track during finishing.

But the interesting part is the two vertical pins. This track link shape is known as an odd side pattern. The pattern is one piece so I'm thinking it must have been placed pins downward into a complimentary shape (can't think of the name) that defined the parting surface. The top half was rammed up in a flask and screed off and then the whole carefully turned over on the moulding board and this other mystery shape removed and parting powder sprinkled over the parting surface and then the other half of the flask fitted onto the first and then this second side of the pattern was rammed up.

Regards

Alex

[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

[RichardT10829]

Yep you got my pulse racing if there is anything i can do to assist let me know

[matt_mcleod]

Hello gents,
Thankyou for the public and private messages of welcome and support for our investigation.

I had a look at a couple of carriers yesterday, both for the tracks and to help a friend draw up the front armour plates for reproduction (if anyone is interested in these drawings I will send copies when they are finished).

I also re-measured a couple of brand new links to clarify the pin bores. My measurements would indicate the bore in the link is nominally 0.5mm greater in diameter than the maximum pin diameter.

ie (according to Nigel Watson's text) the new pin diameter is allowed to vary between:
Max 0.437" (11.10mm)
Min 0.432" (10.97mm)

My measurement of a link bore (taken three times) averaged out to 11.6mm. If anyone has a link lying around and can take a measurement to confirm this as a suitable target diameter for the bores - that would be great.

On the topic on pins, I had a discussion with our patternmaker who has contacts at Ajax Fasteners here in Australia. We will ask them for a quote, and have also sent a pin drawing to China.

We have had a number of discussions regarding pin materials and pin retention and would be interested in some feedback from the forum. As was mentioned above, I understand the pins were case hardened along "most" of their length. This would have been done for wear resistance, but still allowing the softer end to be peened over.

Frankly, heat treating pins adds another sub-contract operation which means more cost. We have considered using a high carbon steel like 1040 in an attempt to maintain some surface hardness without adding another manufacturing operation. With the expected use of restored carriers in mind (ie they are not in war service) we propose this will provide a cost-effective alternative.

With respect to pin retention, there are a number of options. The NOS track I inspected today used a small collar on the straight end and appeared to be simply peened over with a hammer. Nigel's book shows factory tracks having a domed, riveted head. There is also mention of "welded caps". Service track sections are joined with split pins. Aussie tracks use lead plugs.

Here are the pros and cons of each (from a manufacturing perspective):
[1] Collar/peened: Pros - cheap and easy, Cons - lots of labour, assumes 1040 high carbon steel can be peened in this manner (we'd have to make a sample pin and try it)
[2] Domed/riveted head: Pros - very strong, Cons - needs special tooling to achieve, would have to sub contract and ship big heavy link sections around
[3] Welded Caps (using a collar as per [1] and TIG welding the collar to the end of the pin): Pros - strong, relatively cheap, Cons - can't think of any
[4] Split pins: Pros - easy to assemble/disassemble, could be assembled by end user, pack tighter in crate for cheaper shipping, Cons - Retention relies on a small split pin
[5] Lead plugs: Pros - can't think of any, Cons - another part, another material, more cost, questionable whether we can reproduce the dimensions and achieve acceptable pin retention.

On the topic of strength using split pins, I don't believe this is valid option. When turning the carrier, the track is curved and hence the forces generating the turn are transferred to the washer and therefore the small split pin is loaded in shear. This would be acceptable for joining service link sections, but I would consider this poor engineering practice if used to join all the links.

My preference is for [3] Welded caps, but interested in the feedback from members. If this was selected and if the repro track manufacturing goes ahead, I would propose service link sections would be pre-assembled and stacked in a custom-built crate for shipping. End users would then assemble the service link sections with split pins as per original supply.

Anyway, enough for today. Would appreciate any thoughts, feedback or comments.

Regards,
Matt McLeod

[cantankrs]

Hi Matt,

Well done giving replacement track this detailed investigation!

I would like to offer a few comments, set out below.

Originally Posted by matt_mcleod

...to help a friend draw up the front armour plates for reproduction (if anyone is interested in these drawings I will send copies when they are finished).

From memory I think RichardT10829 and also Martyn have done a lot of work in respect of armour drawings for English/Canadian Carriers. If that's news then search MLU or you might wish to PM Richard to compare notes.

Originally Posted by matt_mcleod

[5] Lead plugs: Pros - can't think of any, Cons - another part, another material, more cost, questionable whether we can reproduce the dimensions and achieve acceptable pin retention.

I've seen NOS lead plugs and while they're another part, the ones I've seen were simply a cylindrical slug of lead. Deforming them into the end of the track seems to be the effort required for assembly. I do admit however that I'm not familiar with what shape the track link takes that accepts the lead plug. I don't know if it's as cast or machined.

Originally Posted by matt_mcleod

On the topic of strength using split pins, I don't believe this is valid option. When turning the carrier, the track is curved and hence the forces generating the turn are transferred to the washer and therefore the small split pin is loaded in shear. This would be acceptable for joining service link sections, but I would consider this poor engineering practice if used to join all the links.

I've reread this and see your point about using it only for joining such as a master link in a drive chain. But my observation, if I understand its function correctly, is that the interlocking of the track links defines the total sideways movement of adjacent track links, so if the pin is long enough (and not seized in either track link) then the washer or retainer should not receive load that would shear the pin. The question to ask seems to be is there a history of these pins being sheared during operation?

Regards

Alex

[Lynn Eades]

The lead plug is easy. I cant really remember which calibre, but some of the guys use cast lead bullets, which are easy to make(.45 cal?).
Re retention with a split pin, it worked in service, and I concur with Alex, that infact there is virtually nill end load on the pin in normal use.
A thought, that sits in the back of my mind is that anyone wanting repo track, would want it to look original.
The track pins I have, have different heads, some appear to be made like a rivet (The pin being held, and a head formed by hitting it) some look like they are rolled( the head appears to be formed by rolling the material back on its self, and you can see in under the head from the pin end, around the pin circumference)
I believe you are headed in the right direction, with your welded head option.
If your run of English/Canadian track is a success, do you intend to do the Aust. pattern track?
I have just looked at an Australian manual, and it states the track links are made of malleable iron.
The track displacement is 5/8" not 3/8" as I previously stated.

[ron]

Hi Lyn. 38 wad cutter bullets are perfect if cast in pure lead, regards Ron

[Lynn Eades]

I should have known you'd be the man.

[cantankrs]

Mostly off-topic story. But related to imported foundry work. My Dad used to work for a firm down in Perth that in the late 60's imported single cylinder stationary diesel engines similar to a Lister design that were made in India. They proved to be OK engines, certainly the mk2 with the better crank/bearings was very good. My Dad actually bought one 20 years ago second hand cos he admired them for their price. They were beautifully finished on the outside, but still had casting sand in places inside! So the workshop fellas in Perth had to strip every one and clean them out thoroughly and reassemble them before sale.

Regards

Alex

[Perry Kitson]

I had a couple of Canadian UC track pins tested for composition a number of years ago, here is what I found,

Ni 2.31%
Mn 1.53%
Cr .31%
Fe 95.06%

case hardened 56-58 Rc.

Hope this helps.

Perry

[cantankrs]

Hi Kerry,

Is there something wrong with my adding cos I get a 0.79% shortfall from your figures. Can you check?

Regards

Alex

[Lynn Eades]

My guess is there is a bit of carbon in there somewhere....as well as a bit of mud from the Thames, and a bit of sheepshit

[cantankrs]

Originally Posted by Lynn Eades

My guess is there is a bit of carbon in there somewhere....as well as a bit of mud from the Thames, and a bit of sheepshit

Alex

[cantankrs]

Here's a link to an old thread re digitising a track link.

Regards

Alex

[cantankrs]

Here's another link to an old thread discussing track and with some neat pics.

Regards

Alex

[David Ellery]

Last saturday I helped out a member of our club down the line in soughting unused LP2 track which he had purchased. Most of the track is NZ manufactured I presumed by Mason & Porter (now Masport) the remainder I took to be from A&G Price from Thames south of Auckland until I looked back over this thread and saw on page 2 the pics from Ron. The track I was soughting has the same markings as Rons so obviously has come across the tasman which historically is rare since at the time Australia was pushed in trying to supply themselves let alone send it to NZ. I was impressed in the finished product of the Aussie track compared to the other, very clean and sharp detailing. Had to share this as it took a while to stop the drooling after handling such tight unused track.

[cantankrs]

Very interesting David, also I hadn't known the Mason & Porter connection.

Regards

Alex

[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.

[ron]

Thanks for posting the information regarding the casting of new track,I found it to be very interesting,its now up to the guys who need new track to get together and poole their resources,its no good just dreaming about it,when I needed new rubber on some of my carrier wheels I had a mould made, you have to do it no one is going to do it for you, and if they do you will certainly pay for it, I am lucky I have a good supply of N O S track enough to take care of my requierments, So now you guys who want track for your Aust carriers,its now come on Aussie, come on time, in other words put your money where your mouth is and get off your backsides, this is not intended as a shot at any one , just a wake up call the fact is its never going to get any cheaper in the future, good luck Ron

[cantankrs]

Hi Dreadnought1, Welcome to the MLU forum!

Some more pics of the SEW Freo patterns would be appreciated by all I'm sure.

Making the cast iron malleable rather than just recasting gray iron is about the only thing to add.

The following from http://www.keytometals.com/Articles/Art96.htm covers it very well. I've quoted the generic contents as far as possible. Visit the link above for more detail.

...Charge materials (foundry returns, steel scrap, ferroalloys, and, except in cupola melting, carbon) are carefully selected, and the melting operation is well controlled to produce metal having the desired composition and properties. Minor corrections in composition and pouring temperature are made in the second stage of duplex melting, but most of the process control is done in the primary melting furnace...

... In general, the technology of molding and pouring malleable iron is similar to that used to produce gray iron. Heat treating is done in high-production controlled-atmosphere continuous furnaces or batch-type furnaces, again depending on production requirements.

After solidification and cooling, the metal is in a white iron state, and gates, sprues, and feeders can be easily removed from the castings by impact. This operation, called spruing, is generally performed manually with a hammer... ...After spruing, the castings proceed to heat treatment, while gates and risers are returned to the melting department for reprocessing.

Regards

Alex