Making a track punch

[Lew Skelton]

So, I sourced an old cut in half suspension rod ( because they are super hard) borrowed a track punch from Alex and set to on the lathe at work during lunchtime. Here is the progress so far. Going to button weld the head on then cut the sides off the head and grind to shape.

[Robin Craig]

For what track is the punch for?

The upper one which I am taking as the one you are copying looks familiar to me.

R

[Lew Skelton]

The punch is for an LP carrier, I'm copying a punch from an FV432 that is very similar to wartime production carrier punches.

[carrierbarry]

Will you sell them if they are a success ?

Barry

[Lew Skelton]

All I've managed in the last couple of days has been to cut the rod to length and start shaping the head, I may get a bit of grinder time in thismorning. Will post some progress hopefully later today.

[Lynn Eades]

Lew, are you aware that there is also a short punch?
I thought the the LP2 style was only from octagonal stock (no big end)
Nice work!

[Lew Skelton]

Nil progress on the punch. I took the carrier out for a lap of the block then took the jeep out to the beach. I havn't seen a short punch Lynn but had noticed this one will easily go all the way thru the track plus some!

Any pictures of an LP punch in the album there Lynn?

[Lynn Eades]

Lew, Sorry, no. Hopefully someone else can post pics.

[Jim Baker]

Hi Lew,

Here is a photo of the two track punches.

[Lew Skelton]

All done, cheers for the info re LP punches Jim and Lynn. I ended up linishing the head to shape after welding it on. Oh well what to make next?

[Lew Skelton]

Here is another angle

[Tony Smith]

Would the Short Punch be for upset forming the lead plugs, rather than actually driving the track pins? It's not clear in the pic, but it looks to be a slightly larger diameter than the long punch.

[Jim Baker]

The short punch is pretty much the same diameter as the long one, I use it to start moving the pin out then use the long one. I don't know what sort of steel is used in the long one but it bends fairly easily.

[eddy8men]

I have a few 432 track punches but prefer to use an old short pin and a broken piece of track.
the broken piece of track holds the pin in place while you apply a little variable pressure with a sledge hammer.
works everytime

rick

[kevin powles]

Originally Posted by eddy8men

I have a few 432 track punches but prefer to use an old short pin and a broken piece of track.
the broken piece of track holds the pin in place while you apply a little variable pressure with a sledge hammer.
works everytime

rick

Rick, sounds like you back working on the carrier.

[eddy8men]

the engine's being rebuilt as we speak

[Lynn Eades]

I think as Jim says, The short one is a lot stronger, and does the job of "destabalising" the pin from its working position (from there on in normal usage) it would be an easy job to chase out with the long one. fifty or sixty years of rust was never in the equation.
I do think Jim's short punch is a little on the short side (shorter than mine as I recall) (I haven't seen it for a while though)

[Jim Baker]

My short punch has had a lot of work over the years, the long one not so much. I didn't want to break it so once I got a pin moving I would use another track pin to drive it out. Are other peoples long punches made of soft material? As lynn said adding 50-60 odd years of rust alters the equation and tends to bend the long punch

[Ben]

I bought and use a modern cvrt/432 track pin punch, it needs about 0.5mm turning off the diameter on the lathe but it's easy to do.

Works well but I've not tried hitting stuck pins, I suspect it would bend. It's almost identical to the original item.

[Stew Robertson]

Is the short punch not for knocking the heads off the pins and the long ones for driving the pins out
Just a question

[Marc van Aalderen]

Hi Stew,

How are you doing?

I think the short one is for forming the lead end-plugs, as Tony Smith already mentioned in post #12. The little tip is to short to even touch the pin. There must be another tool to hold on the opposite side while you deform the lead plugs that keep the pins in place?

Cheers,

[Tony Smith]

Aust (and NZ) Local Pattern track is different to UK and CDN track in that the track pins fit into a blind hole (not exactly, there is a small hole at the hull end of the pin bore, but it is much smaller than the pin dia.) and are retained by a lead plug on the outer end of the pin. The pins are plain rods with no heads or drillings for split pins. The lead plug is the same dia as at track pin, but is retained by deforming the lead into a groove in the bore.

To remove the pin, you punch the end of the pin through the small hole. You must provide enough force to both dislodge the weathered pin, and also to shear the rib of lead that has flowed into the groove.

While I still think this short pin would be ideal to use for compressing the lead plug, I also agree that it is probably a better tool to use for the force required to achieve the initial movement in removing a tight pin and plug than the long punch.

So to clarify that we're on the right track (pardon the pun), are both the short and long punches small enough to fit in the small hole at the end of the pin bore, or are they the same dia as a track pin?

[Tony Smith]

Now having written that, I see in Lew's pics of the finished product that the track he's using has track pins with heads! Is this UK track, or do NZ LP2A carriers use different design track to Aussie ones?

[Lauren Child]

While I have used one of these type pins as a track pin punch I don't think thats what it's meant for. The real track pin punches are rather more robust and don't bend like the one in the first post has.

I believe these pins are actually meant to hold CVR(T) track together and aligned while popping another pin in.

[Richard Farrant]

Originally Posted by Lauren Child

I believe these pins are actually meant to hold CVR(T) track together and aligned while popping another pin in.

Lauren,
You are correct in that they were only to align, when CVR(T) pins were removed it was with an extractor that screwed on to the pin. Knocking them out would have damaged the thread.
Sorry, nothing to do with Carriers, but just to clarify.

[Lauren Child]

Here's a pic of some actual track punches next to the type you've got. The heads are round and are flatter (though slightly domed) so the force is applied straight on to the end of the pin. Between the angle of the hit and the material it's made of it seems much less prone to bending. The holder keeps your fingers out of the way while walloping.

If you've got some of the hard material left I'd make one like this.

[Lynn Eades]

Hi Guys, This thread is Lew's thread about making a track pin punch.
It is a little complicated as he has made a punch for British or Canadian track pins.
As has already been explained, his carrier in an LP2 (LP2A?, sorry Lew, I forget) and the construction of the track is different from those above mentioned.
Lews track pins are (or should be) held in with a lead plug (already mentioned) on one side, and they do not fall out the other side because the exit from the link has too small a hole. The main purpose of that hole is to allow the removal of the pin, with a punch that fits through that hole.
The manufacturers specs for British track pins are between 0.432" and 0.437" in dia. (nom.7/16") (near enough to 11mm) I believe that all "normal" (Brit, Can. Aust.)carrier track pins are this dia.
A track pin punch for British and Canadian carriers only needs to be a little less in diameter.
As different, the Australian and New Zealand carrier track pin punch (333/2) can only be quite small in diameter to fit through the hole, and my one happens to be about 0.310" (about 7.8mm) My "starter" punch (333/1)(short one) is the same dia. These punches are soft, and mine is somewhat bent out of shape.
What needs to be taken into consideration is that when the carriers were in regular use, the track links and pins never wore or rusted like they have in post military service, and the pins were much easier to remove than we may experience
I haven't read the detail, but I believe the starter punch, Aust. Carrier part number 333/1, is the punch that did the hard work of "upsetting" the track pin from its place of work, in the links (including breaking out the lead plug) The first 1/4 to 1/2 inch of travel causing the most resistance, in "normal" conditions.
The long punch, part number 333/2 has to be long to chase out the pin, but did not have to be very strong.
My 333/1 starter punch is about 15/16" (24mm) long from the end to the start of the radius. It is made from octagonal stock that is 19mm (3/4") across the flats.
Just to cause confusion, I have a large diameter (and seemingly stronger punch of the same style) that would be for use with Brit/Can. style pinned and headed type track pins. It bears no part number.
Maybe it is local production or was for use with the Vickers MkVIa track which fits Australian carrier wheels, but was of the track pin type located with formed heads.
Lew, I can bring them with me,when I visit.

[Lew Skelton]

Well, we have basically covered off on all types of punch and there uses. Cheers for the discussion and pictures, I'm sure regardless of what type of carrier/CVRT or FV we have all picked up on something due to the collective wisdom from forum members, cheers!
As a side topic my electronic dizzy conversion is all but done, will chuck up a post in a few days.

Lew

[Rob Beale]

There was a holdup in the production of track in NZ due to other work at the foundry in Auckland. So a batch or two of track was ordered from the USA (as well as track from Australia).

I believe it is the US produced track that has riveted pins and the wider spaced track horns as with all LP carrier track while the Aussie track is likely to be the lead plugged style same as NZ made track.

Rob

[Lynn Eades]

But not all Aussie track is lead plugged (now that you point it out) because Aussie would have had a stock of Brit made track for the Vickers light tanks (MkVIa) which I believe was of the type with heads on the pins.