which way around the tracks?

[andrew honychurch]

Time for a silly question! Is there a correct way around to fit the tracks on my T16? I can see that they are different front to back but does it make any difference and why?

Also, need a radiator cap for the T16, anyone got one spare please?

thx

Andrew

[Ron Pier]

Andrew this question was asked a long time ago. When the answer was delivered I ran to the shed to make sure mine were on the correct way round......and the are. They will work the other way round of course, and someone posted a picture of a carrier in service with one track arse about face.

Ron (Poole)

[andrew honychurch]

so looking at your photo the tapered chevron points forward. which I suppose would be obvious. no mention of it in my TM at all. . thanks

[andrew honychurch]

thanks Michael, plenty for me to read up there! It seems looking at my own old photos, this was the way they were around! I assume therefore they were correct after all. I just wanted to make sure, as sometimes when I look at them , I cannot see a difference, must be my age.

[Bob Moseley (RIP)]

Hi Michael - thank you for referring my research on track orientation. I feel comfortable with my findings although a very knowledegable gentleman mate of mine disputes my findings and we have had many vigorous discussions on the subject. Anyway research is only there to guide readers to make up their own minds.

Bob

[Lynn Eades]

Your research is somewhat mis-leading.
The Aust. book for Carriers, M.G., 2 pdr, and 3" mortar, says short side to the front.(on the ground) HOWEVER, the same paragraph also states that the NZ carrier tracks are fitted the opposite way.
The Canadian book, UC-F1 Describes fitting as("top run over the guide roller") Double lug to the front. (short side forward at the top)This is the opposite, to the Australian way of fitting the track.
It might be a good idea for Andrew to refer to a T16 manual.
My research indicates that you have a 50 percent chance of being correct. ( that is unless there is a third way to fit them)
Who knows if one way increases track life, or possibly better traction.
I remain open minded and polite. ( I might need an instrument cluster done in the future)

The Brit.Carrier manual (Chilwell No.63/63) describes fitting as per the Candian book; Double lug to the front over the return roller.
So to sum up. Canada, U.K. and N.Z fitted track the opposite way to Australia.
Time for David to give us details on the T 16.

[Bob Moseley (RIP)]

Hi all - I am not sure how much of my research paper was revealed in the above post, but here is the text only again.

Lynn, as a professional researcher, I have always remained neutral on a subject relying only on the available evidence, refer bibliography. In that respect I cannot see how my research can be misleading. It is up to the reader to weigh up the evidence and then come to their own conclusion. It would be interesting to see the reasons why NZ Carriers had their tracks fitted opposite to the Oz ones. Maybe your slopes run the opposite ways to our slopes.

Australian Bren Gun Carrier Tracks – Which Orientation?
(by Bob Moseley – Ph:0421 038 661)

Restoration of any historic item invariably leads to differing viewpoints, whether they be about paint colours, tyres, numerous other items or in this case the orientation of Carrier tracks. During my involvement with the restoration of the National Military Vehicle Museum, Port Adelaide, LP2A Carrier, Hull No. 2340, discussions arose regarding the correct way to fit the track. These discussions quickly extended to other Carrier owners. It appeared, prima facie, that the answer was simply to follow the instruction manuals, but as it turned out, which manual/s? Following a close study of several manuals a number of anomalies between them came to light and after, in excess of 64 years from when the first manual was written, it appears errors in the writing of subsequent manuals may have led to incorrect interpretations from then on.

Research Texts

The primary information sources along with their relevant texts are as follows.

Mechanization Pamphlet No.6 - Carriers Machine Gun - LP No.1
Description, Maintenance, and Operation 1940

Tracks should normally be fitted so that the “tails” or shorter sides of the links are to the rear on the ground or bottom run.

Carriers, Machine Gun L.P., Nos.2 & 2A – Description, Operation and Maintenance Mechanization Pamphlet No. 7 1941

Tracks should be fitted so that the “tails” or shorter sides of the links are to the rear on the section of track in contact with the ground.

This depiction is the reverse view of Figure 2 with Figure 2 being the universal image contained in all the source manuals.

Fig.1 “Tails” to the Rear

Carriers, Machine Gun L.P., Nos.2 & 2A – Workshop Repair and Maintenance Mechanization Pamphlet No. 7A 1941

Tracks should be fitted so that the “tails” or shorter sides of the links are to the front, in relation to the vehicle, on that section of track in contact with the ground.

Depiction ex. Manual.



Fig.2 “Tails” to the Front
Carrier M.G. (Aust.) Instruction Book
(Notified in G.O.’s dated 31st July 1943)

Tracks are fitted so that the “tails” or shorter sides of the links are to the front on the section of track in contact with the ground.(See Figure 2)

Workshop Manual Carriers M.G., 2 pdr. And 3” Mortar (Aust.)
(Undated but appears to be the complimentary volume to the 1943 Instruction Book)

Tracks should be fitted so that the “tails” or shorter sides of the links are to the front, in relation to the vehicle, on that section of track in contact with the ground. (See Figure 2)

Track Assembly

The 1943 Instruction Book describes the assembly of the links to form the track.

1. The “tail” or shorter side of the link meshes with the front or longer side of the next link,……….
Front of Vehicle

Fig.3 Front of Vehicle

It can be seen in Figure 3 that to correctly fit the track assembly description, i.e. shorter side of the link meshes with the front or longer side, the “tails” must be to the rear for the longer side to be to the front.

The Mechanics of a Chain

The 1941 Mechanization Pamphlet describes the track as …links joined together into an endless chain by hardened steel hinge pins.

In simplistic terms a chain can be described as a series of individual links held together with pins. The joined links then provide access spaces for the teeth of a drive sprocket to propel the track. Now imagine a length of link chain. When the two ends are pulled apart the chain is straightened but when the ends are pushed together the chain buckles. Therefore a chain can only operate on a “pulling” force unless the following applies.

When a link chain is employed to operate a piece of machinery two or more sprockets are employed. The primary sprocket is the chain drive sprocket that pulls the chain around itself thus enabling the chain to “pull” the secondary sprocket/s that operates the piece of machinery. However in many instances both the primary and secondary sprockets are fixed to shafts to allow the machinery to be operated both in forward and reverse directions. The application and location of the driving force of the sprocket is dependant on whether forward or reverse motion is required. (See Figure 4)

Fig.4

Reverse drive force is applied at this point

Forward drive force is applied at this point

As a machine is normally required to operate in a forward direction the chain must be designed and oriented in such a way that the chain operates with maximum efficiency and with the least stress.



Fig.5 Direction of Track in Forward Motion with “Tails” to the Front and Rear

In Figure 5 with the “tails” to the front it can be seen that the links, on being engaged by the drive sprocket, are being both pulled and pushed. The pulling force is being exerted on front edge of the link pin whilst the pushing force is being exerted on the rear edge of the same pin. These opposing forces are also being transmitted into the two holes the pin sits in. However with the “tails” to the rear only a pulling force is applied to the link pin and holes. This in turn would result in less wear in the track components. The other result would be that the maximum energy is utilised as opposed to a loss of energy in overcoming the opposing pull/push forces.

The source manuals further describe a link as follows.

The sole of each link has a ridge or bar running the full width of the link to enable it to grip the ground.

With reference to Figure 6 where the “tails” are depicted to the rear, it can be seen that the first point of contact of the link on the ground is the longer edge of the link. In this orientation the “tails” also resemble two wedges that would bite into the ground prior to and clearing a pathway for the ridge or bar.

A close study of Figure 6 also shows small raised lugs adjacent to the sprocket teeth holes. These lugs would be the contact point between the sprocket tooth and the link and would provide both strength and wear protection at that point of contact. If the “tails” were to the front these lugs would not be utilised.
Fig.6 Track link detail
Figure 6 is the track fitted to Carrier 2340 that has “41” cast into its links denoting a 1941 manufacture.

The overall result of the above arguments may appear subtle and minimal, but over a period of time these factors would affect the wear and eventual breakdown of the tracks. Bear in mind the tracks were made of “malleable cast iron” with the non-lubricated joining pins and pin holes being subjected to enormous friction and stresses.

What is the Answer?

The most important issue to consider is that the only correct benchmarks must be those detailed in the original design specifications utilised by the construction workshops that built the Carriers. Once the Carriers were released to the military they were immediately subjected to whatever the military workshop manuals and procedures stated and not what was originally designed.

The “tails” to the rear theory is supported by the following facts:

1. Written references in the LP1 and Pamphlet 7 manuals.

2. The Carrier images and those relating to tracks depicted in these manuals to support the instructions. (Figures 7 & 7a)

3. The fact that these images were never changed in the subsequent manuals. If it was felt necessary to amend the written text, then that amendment should also have been carried through to changing the images. The old adage of “a picture says a thousand words” is very true. More notice is likely to be taken of an image than the written word and hence an incorrect image
Fig.7 & 7a

would be very damaging when used to support an amendment.

4. Photographs of Carriers during the testing phase at their time of completion by the construction workshops. These photographs originate from South Australia in 1941 (Figure 8 and West Australia in 1943 Figure 8a) and are owned by the military test driver from that time.

Fig.8 South Australia 1941 – Carrier 174 Fig.8a West Australia 1943 – Carrier 5086

Conclusion

Track failure was common and just possibly this may have been caused by the incorrect refitting of tracks through following the possibly incorrect instructions in the later manuals. Given the wartime situation and the military ideology not to question but to follow orders, the situation perpetuated until the Carriers were phased out, and then it didn’t matter anymore.

As stated in the opening, restoration always leads to differing viewpoints. The restorer must determine what point in the history of the vehicle is being represented, i.e. its time of manufacture or some time during its service history. Care should also be taken upon which documentation to rely especially with the dates of writing. For example with the Museum Carrier 2340 that was manufactured in 1941, the only relevant manual should be Pamphlet 7 as it was promulgated 1st June 1941 whereas its companion Workshop Manual was promulgated on 31st December 1941 at which time all 1941 Carriers had been built.

Bibliography

Mechanization Pamphlet No.6 - Carriers Machine Gun - LP No.1
Description, Maintenance, and Operation 1940
(Notified in A.A.O’s dated 30th November 1940)

Carriers, Machine Gun - L.P., Nos.2 & 2A – Description, Operation and Maintenance Mechanization Pamphlet No. 7 1941
(Notified in A.A.O’s dated 1st June 1941)

Carriers, Machine Gun - L.P., Nos.2 & 2A – Workshop Repair and Maintenance
Mechanization Pamphlet No. 7A 1941
(Notified in A.A.O’s dated 31st December 1941)

Carrier M.G. (Aust.) Instruction Book
(Notified in G.O.’s dated 31st July 1943)

Workshop Manual Carriers - M.G., 2 pdr. And 3” Mortar (Aust.)
(Undated but appears to be the complimentary volume to the 1943 Instruction Book)

Australian Military Equipment Profiles – Vol.2 Local Pattern Carriers 1939-1945 by Michael K. Cecil – Published 1992

Several sparring partners

[eddy8men]

andrew have you got an instruction manual for the t16, i would assume the correct way to fit the tracks is described in it, if you haven't got one yet you might aswell bite the bullet and buy one as you can't do user maintenance without it

rick

[tankbarrell]

It doesn't specify in the TM but the photos show spud trailing at the front in normal British practice.

[Euan McDonald]

It would seem to me that Aussie track could be fitted in reverse to gain extra grip to allow us to drive upside down as we are from the lucky country down under.