We're in the process of doing a little light truck overhaul work on a couple of former Southern Railway heavyweight passenger cars. In the process of "getting our ducks in a row" we've printed off the truck drawings from our aperture card file and found several truck components show being made from wrought iron??? Specifically, we're finding equalizers and swing hanger cross bars made from the stuff. I'm used to these items being forged steel and have some idea how to handle a reclamation project on that kind of material. We've never had to deal with the wrought iron and were wondering if anybody else has and/or has any suggestions on how to handle reclaim work on these parts? Is there a welding process or are they essentially throw away items?

These cars are not subject to being Amtrak approved, at least not on their current trucks, so doing the work to their standards is not an issue for us. However we like to keep the cars in a condition where they could safely make a freight move and not cause anybody any problems or cause me any sleepless nights! Any suggestions/advice would be greatly appreciated.

What do you want to know about wrought iron? Are you just cleaning painting or will you need to do machining ot forging? Forging wrought is different from forging mild steel in that you have to work at a much higher temp & keep it hot. Wrought iron has little to no carbon but can & usually does have other garbage in it. Wrought is a pretty inconsistent product & that is just from the way it is made. The better - more refined wrought has been worked to get all the silica & other garbage forged out of the material. Wrought is very easy to forge weld compared to modern steels & many parts onold equipment that look machined or cast were infact forge welded from many pieces of wrought iron. Most anvils were made of 5 pieces of wrought, forge welded together with a hard tool steel plate forge welded to the top.
Sorry, I used to be a blacksmith so I have a little insite on wrought iron.

Dave Huffman

Over time these components develop wear. Usually the equalizer feet where they contact the top of the equalizer seat, or the sides rub against the equalizer seats or pedestal legs or other places. If it were a steel part it could be welded up and heat treated provided it was not worn in excess of certain limits and the hardness of the part could be maintained. So what we're trying to determine is if there is a similar process for the wrought iron. I can't imagine that this is the first time this has come up, but who knows...

Probably the best way to repair that wear would be to have a blacksmith forge weld more wrought iron where the wear is & then machine or grind to spec. Electric welding wrought iron can be a real crap shoot as there is so much variation in the base metal. Wrought iron is a very different beast than carbon steel.

Dave Huffman

Here is a link to a picture on the RPCA website that gives a good idea of the type of wear we would be concerned with.

http://www.rpca.com/defect2-27.jpg

These equalizers are quite heavy and have to be moved by fork truck or crane.

Are your drawings dated close to the last overhaul date for your trucks, many RR drawings were updated with different materials and/ or are your parts still wrought iron??? I would suggest someone do a spark test and/or a chemical analysis on the material in question. Out of date paperwork, as well as newer paperwork that does not apply because your car or locomotive never received that update has lead more than one restoration group down the wrong path for repair procedures.

Mike Tillger

Whichever it is - wrought or steel - isn't going to be an esoteric alloy, just a common variety. Wrought is not hard to build up, but you may need to try a variety of fillers to see what it likes. I've had a lot of success using a MIG setup with nonferrous wire, such as aluminum bronze. If the wear is just as shallow as the photos show, probably the ability of the parts to accomodate the mechanical stress is within margin since these things were very overbuilt, so making them fit better is the challenge here. Run some calculations to be belt and suspenders if you like.

Spark test will tell if the metal is towards the steelish or ironic end of the spectrum. This will help you settle on a narrower range of filler metals to experiement with.

Best wishes and try not to overthink this.

dave

Would machining and addition of a wear plate work? Just a thought... you're more readily knowledgeable on what's "legal" per AAR practice than I. Otherwise, looks like some major preheating is going to be a requirement to do a proper build up repair by brazing or welding.

Let us know what you come up with. Would be interested to know how you dealt with the problem.

Best,
Mike

Being as wrought iron is very low in carbon I would go with a low carbon welding rod. Wrought iron will hardly cut with a torch because there is no or little carbon to burn which is what happens with a cutting torch.

DBH