Firefly tank

[David Herbert]

Thanks for posting those pictures Bob. As you see they have broken the track under the sprocket and run it off backwards, much easier.

As you say the jack they are using in the photo is made by Simplex and is actually a standard multi purpose jack of the day. I got mine from a non military autojumble here in the UK. They very quickly realised that the use of chains was a bit ackward and supplied adaptors that hooked into the track and the jack but that scheme didn't last long either.

Next came specially designed track jacks (also made by Simplex) that were used in handed pairs and were designed to be a universal tool for all WW2 US tracked vehicles. In theory they would also pull the end connectors which would have been a great help but they were not really up to that job on Shermans once the track had been in sevice for a year or so and gone a bit rusty. They were long enough that you could hook onto links that were either side of a damaged link, take the tension with the jacks, replace the link and remove the jacks, all without un tensioning the track.

Don't forget that the manual that you are quoting from is the first attempt at a TM on Sherman and was written before any real experience had been gained in service. Later editions are a bit more realistic.

David

[Bruce Parker (RIP)]

Originally Posted by tankbarrell

That's a D68735 50 round .50 cal box. Sometimes seen in white, other times OD, both correct.

It makes sense if the white ones were from vehicles such as Fox but is that confirmed?

Fox ones are indeed white, but they are also unique to Fox. They were never meant to be used on the outside as they fed the M2 mounted through the turret mantlet.

[tankbarrell]

Originally Posted by Bruce Parker

Fox ones are indeed white, but they are also unique to Fox. They were never meant to be used on the outside as they fed the M2 mounted through the turret mantlet.

Indeed, but that is not the box in Jacks picture.

[Lynn Eades]

With reference to Motto's and David's posts about "live track", I don't have too much knowledge about tank tracks, and I agree they are "live" tracks, but not because of the way they are made, but because a tank track or "live" track "soaks up" what it travels over,(the bottom rollers move up over objects, and allow smooth passage over them) as opposed to a bulldozer that climbs up on to an object and when it passes its balance point it flops down the other side This is not a "live" track because it has a fixed track frame with fixed bottom rollers.

[David Herbert]

Sorry, Lynn, but you are wrong.

What you describe is a tracked vehicle with suspension. Live track is most definately the track itself. Instead of each link being completely free to hinge to its neighbour (it just lies there as if dead) it is hinged with rubber bushes so that each link not only pulls the next one but also tries to even out the angles at the pins. When working on this type of track it very much has a life of its own and stores up a lot of energy when folded over onto itself which can result in it suddenly flipping over as it tries to resume its built in curve.

Just to be really pedantic "bottom rollers" is the term used in construction plant. In tanks and similar military vehicles they are known as "road wheels" if they are big ones as on Cromwell probably because they are really too big to look like rollers. On Shermans and even Churchills the manuals call them "bogie wheels". In tanks that have small rollers to carry the top run of the track the terms "top roller" and "support roller" are normal. You will certainly find variations on what I have just written but my point is that "bottom roller" is not a term used officialy with tanks.

I hope that I havn't offended

David

[Lynn Eades]

No David, not offended. I just had an adjustment made to my data storage system.
BTW this reply has been severely altered, after a quick circuit of google.

[Bruce Parker (RIP)]

Originally Posted by tankbarrell

Indeed, but that is not the box in Jacks picture.

I know that!!! Just filling in the details, kind of big picture thing...

[tankbarrell]

I knew you knew that Bruce......

[Bob Cohoon]

I was reading the comments about "live" track and found exactly how it`s done in the M4 manual. Apparently the track blocks consist of two steel tubes with steel end plates attached to them. the rubber block is molded around that. The connecting pins have rubber "doughnuts" ( description in manual), or sleeves , vulcanised to them and are pressed in , into the tubes in the block assemblies.The connecting pins have grooves in them at their ends ,and the pins are pressed in so that these grooves are 90 degrees to the track surface. When the block assemblies are connected to each other with the main track connectors/ guide horns, they are locked in place with a wedge which has a 7 1/2 degree angle on each end of it and this engages the grooves in the pins. the two 7 1/2 degree angles then force a 15 degree angle between each block assembly.This is why the track wants not to lay flat when loose, but wants to curl up slightly, if the pin rubbers are still in good shape. Sometimes the pin rubbers will shear and this results in a loose pin and what the book calls a "dead" block, which usually requires replacing asap, as it can affect the action of the track. I think even later types of track, like M48 tank track, uses this idea

[Robert Bergeron]

Guys,

The Shermans in the picture are so new there are no machine guns mounted on any of them. No co-ax, bow or crew commander MG.No towing cables , Jerry cans , antennae , no nothing . Looks they were just dumped or driven on the side of a road somewere in England to be seviced , equiped and readied for action.

That there be no markings is not suprising as more important stuff needs to be done first like loading the MG's and radio equipment .

Nice , colour and stenciled markings is the stuff you do when in garrison not when you are about to embark on history's most important flotilla or Armada to date .

On the LCT's we see embarcation markings in chalk . It did the job.

The silly stars our allies insisted on us painting on the sides of our Shermans were just so nice to the Jerry's as aiming marks. Just like the nice standing MG mounts on US Jeeps. Better targets , soon jettisoned pieces of bad and ill conceived in garrison equipment.

I see a barrel of grease and a wooden box in front of the first one . Would that box contain a Browning MG ?

My two cents as an amateur history buff and modern military man.



Cheers . Salute a veteran and thank him today and every day of the year.

Robert