new carrier track pins
 

Last for sale was about 2 years back and were salvaged from an assembled track.

I have three tracks soaking in molasses and water to remove the rust. I am trying to prepair for pullign them out in a few months to see what condition they are in.

I expect to need to replace a few pins, but they could all be bad.

I am thinking to take one of my few NOS repair pins to a machine shop to get more made.

Has anyone else already gone through this? If it was successful, could you recommend a contact?

If I go to get enough pins to simply replace the pin in every link I guess I am looking at 250-300 pins.

If I go this route, is anyone else in the same situation? Not buying a few pins, but around 150-300?

Just a show of hands if you are at all interested. Obviously, final price may change your mind.

if someone had a shop make them up before, what kind of price did you end up paying?

I haven't done it but think it's worth while. Rather than machining I'd go with lengths of 7/16" rod with a washer welded to one side. Same on the other unless you want to do the whole track with cotter pin/washers.

I think this may be an option to give more life to worn out track. The holes in the track links wear to oval which you can't do much with, but the links themselves wear and 'notch' on the bearing surfaces so replacing them with as new diameter pins will gain you back a good number of links.

Wouldn't be too hard to make up a little jig to go in a press to form the heads on some 7/16" rod, they're not flared out all that much. Do 5 at a time or something like that. The trouble here in NZ is getting 7/16" rod in anything more than mild.

I'm using lead plug track, so it's just plain pins. Otherwise it'd be fun to have a go at making some headed pins :)

Track Pin making
 

Back in the day, steel companies over here imported 7/16" "centreless" ground rod. I think this was a medium tensile steel and I guess you would still get this State side. As Alex has eluded to , it would be far more cost effective to form the head by the rivet making method, ie. heating the end whacking with a former. We made rivets for the M3 Stuart Tank in an old railways rivet making machine, which all you had to do was cut the rod to length, heat the end, drop it in the holder, and pull the lever, and "wamo" , you had a rivet , so making a track pin is the same principle, just using a longer shaft. Cheers Andrew.

I have LOTS of these to make... I need to find one of the many old track pin threads to get the exact steel, but from memory it was a chromoly type steel.


DO NOT USE STAINLESS


If you are forming the heads you will need to make a precision jig for the pin to prevent swelling at the formed end.

I am currently making rivet snaps for people at the moment, so perhaps I need to make a tool for the pin ends too :)

I don't like the idea of the entire track length being pinned using split pins (cotter pins to the Colonials)

I have an idea of forming a second threaded button which can be wound onto the pin once fitted with suitable compound to fix it in place.

In our small "Suffolk Syndicate" this will be my project for the builds we have ahead this year.

The pins were heat treated, but the heads were soft. Yes 7/16" (0.437???)

That being the case Lynn, get the steel, form the ends etc then send them off for heat treatment to harden. :) place near me can do that no probs.

Richard... would it make sense to join forces to get a shit-load of them made up?

I wish I could have all the pins reened at both ends, but can live with the washers and split pins on the inside and not really visable.

Sounds like adding a washer and welding the washer on may make it harder to knock one out for shortening a link or fixing a break in the field.

I am thinking all the longer ones with the hole drilled.

I would be up for 300.

I have a good machine shop nearby, but have not run this project by them. I am wary that their solution would be expensive....

Jim

Molasses rust removal - suggest you inspect the pins before leaving them immerse too long. I had an experiment going which was full strength molasses, and the acids removed visible portions of the surface. The tell-tale was a black slurry in the bottom of the container.

A number of years ago I had one of my new pins tested for composition, with the results posted here (can't find the post). I will look through my notes to see if I can find it. One option for worn track is to use 12mm dia. material (.472") to replace the 7/16 dia. (.437") of the original pins, giving new life to old, worn track. As Bruce says, the hole wear into an oval shape, so you would have to make sure that the holes were large enough to accept .035" larger pins. The pins were case hardened to 55-56 RC.(that's 560 to 575 Brinell for you non colonial types).
Just found my post!
This may help. I found some info from when I was researching reproducing track pins. The following is the result from composition testing on the Canadian track pins.

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

Prior analysis by Marc v.A. and Stephen D.

Jim,

Never put split pins on the inside of the track! If one breaks you will not notice until the track pin goes awol and your track falls apart! For this reason you ONLY put the split pins on the outside so the sound on your hull will alarm you there is a track pin on the loose.

Cheers,