Makeshift Horn for Railcar Coupler Anvil

[carlson]

I bought a piece of 2" x 18" long hot rolled mild steel rod to use create a horn for my railcar coupler anvil.  The attached picture was an earlier picture before I finished up the stand.

The bigger hole in the coupler is approx 1 3/4".  The length the hole passes through the coupler is 8".

Being hot rolled my understanding is that the rod will likely be a bit over 2" OD.

So I'm looking for suggestions on what the best way of getting a horn shaped and mounted in the coupler.

I'm mainly going to use the thick portion for working on hooks and things like that.  The cone portion for bottle openers and opening up curves that got closed up to much.

 

1.)  Shaping the horn.

I imagine a day with an angle grinder and a stack of grinding wheels and flap disk might create the cone section.  I'd be losing material that way though.

I might be able to get some help from one of the professional smiths and a power hammer at our forge meetings.   I wouldn't be losing material that way.

This is a cheap-o project (other than time) but just to throw it out there how long would it take someone in a machine shot with a metal lathe to kick something like that out and would it be prohibitively expensive?

 

2.)  Reducing portion passing through coupler.

Again always have the grinding wheel options.

To reduce on a power hammer do you have to have a sizing block to stop the hammer at the desired size?  Does this sort of operation lend itself to having an end product that would slide into a set size hole or am I asking for a level of precision thats unrealistic.

 

3.)  Mounting to coupler.

Should I just forget about grinding down the pass through portion and just strap it down beside the railroad coupler?

Leave it loose-ish just slid into the hole?

Use some sort of caulk.  I seem to recall posts about Brian Brazeal's thick plate anvils getting mounted using some sort of silicon caulk.  I would imagine epoxy would be too brittle.

Have an inch or so extra out the other end, heat up, and peen over like a big honkin rivet?

 

Thanks in advance for your help.

 

I can get better pictures of everything when I get home tonight.

[ThomasPowers]

 

Talk with a local VoTech machining program and see if they have any way of doing a project.  The last one I used required a donation to their end of the semester party fund that was very reasonable indeed!

[Frosty]

Thomas beat me to it. . . AGAIN. As a "possible" refinement suggestion. 18" is WAY longer than good for a horn, especially starting at 2" dia. 8-10" is longer than necessary but not crazy long. Just because you have 18" doesn't mean you have to use it. The drop is useful for other things in your shop or may be appreciated at the Votech class.

Ask the Votech to turn the cone on one end W/ shoulder, turn the other to fit the coupler snugly and thread it for a lock nut.

Frosty The Lucky.

[Charles R. Stevens]

The other option is to forge it down by hand, good experiance, but an aufly lot of work. Drawing out the point, the trew pin, setting the shoulder and pinch a slot for a wedge are all a learning experiance, especialy in heavy stock. The things you learn trying not to work yourself to death on heavy stock is great experiance for working small stock fast and effeciantly.

[Michael]

Nice coupler by the way! Excellent substitute for an anvil.  I looked into acquiring one of these back when I got started and the restoration railroad enthusiasts were aghast at the idea of using such a precious bit of necessary equipment to pound on.

[ThomasPowers]

I once used a broken one sourced for free; no problem with the Rail enthusiasts  and a decent improv anvil.

[carlson]

Nice coupler by the way! Excellent substitute for an anvil.  I looked into acquiring one of these back when I got started and the restoration railroad enthusiasts were aghast at the idea of using such a precious bit of necessary equipment to pound on.

Well if a restoration railroad enthusiast were to allegedly find an anvil half buried by the side of a railroad track I would theoretically definitely be willing to swap.

Then I could try to come up with an even dumber idea on what to do with this lump of steel. 

[carlson]

Better pictures

 

 

 

 

Edited April 6, 2015 by carlson
Multiple copies of pics

[Frosty]

Charles: I think once the tenon is swaged to fit the hole he should just pein it over. Just think how tight it'd be once it cooled.

Frosty The Lucky.

[carlson]

Thomas and Frosty

I think given the 8 inches through the body of the coupler + maybe an inch of overhanging material on the working end leaves me 9 inches of material I need to shape. 

If I go the machining route I the length won't change. How would you suggest breaking down the remainder. 

Meaning how much of an end should I leave in the back to peen. What kind of slope/taper should I have.

how small should the tip be for working small objects like bottle openers and hooks without being a hazard to get impaled on. 

Thanks for your help. Sorry for the flood of questions.

[carlson]

Charles: I think once the tenon is swaged to fit the hole he should just pein it over. Just think how tight it'd be once it cooled.

Frosty The Lucky.

I seems to me expansion would be most drastic along the length of the bar but do you think it would be an issue in pushing the tenon through the hole.

Do you know if this part is cast and whether there's a potential of cracking it if it cools to tight. 

[Frosty]

I was mostly just joking about peining it like a tenon though it'd work fie. Were I doing it I'd trim it so there's maybe 1/2-3/4" protruding, chamfer and weld it. 9" isn't so long for a horn, I was thinking the knuckle was narrower for some reason and the pics you posted show the relation clearly.

Frosty The Lucky.

[ThomasPowers]

Those knuckles are powerful tough! Think of their use case----a railroad car filled with ton's of stuff gets pulled through one of those *and* transmits the force on down the line to other cars!  As the part that is cooling is the tenon it won't be exerting radial force but the take up in length and I think is would draw the end of a mild steel rod into the hole before cracking.

Traditionally in peening rivets you leave 1.5 times the diameter; if you will not be making a "nice" domed head you can probably get away with less.

I'm getting ready to rivet on a head for another stake anvil and one thing Pep Gomez suggested was to cool the tip of the tenon to use as a hammering stage to swell the shaft of the tenon inside the mortise and then heat the end with a torch and finish off hammering it down.

[JNewman]

This part is not a coupler.  As Frosty and Thomas have mentioned this is a knuckle.  The coupler is the piece that the knuckle is mounted to.  These are a very tough grade of cast steel.  If you can break that by hand I would be seriously impressed.  I have made a pattern  and coreboxes for a knuckle and a couple of body coreboxes for couplers.

Forging the bar down to fit the hole in the knuckle would not be that tough a job with a power hammer with a kiss block but lacking a matching swage I would just forge an octagon that  OD of the peaks of the octagon are the same size as the ID of the hole. 

 

 

 

[LastRonin]

Just an idea... but what about leaving only about 6" sticking out the one end, shape that into your cone/horn and shape the 4" sticking out the other end into another useful shape... squared off to give you the edges your knuckle doesn't have maybe... or even drill and drift a hardy hole in the end sticking out so you can use bottom tools...

[Charles R. Stevens]

If you forge it down and rivit it, give it a big couple of hits with a large sledge, it will upset the shaft some, but after riviting the end, the rod shrinks both ways, so the riivit head and the horn boss will be tight as well.

to draw it down, you first draw down to square, and point the end then draw it out, you will end up with 2-3x the vs the width. So a 2 inch wide horn 4-6" in just fine, draw it down to a fine point. Bicks that fit the track plate holes will be the ticket for smaller stuff, if you can score a 3/4" slice of heavy rail cut of the head, forge the flange to a double horned bick and stick it in one of the holes. So now you have a stuby 2" bick and a fine pointy 3/4 bick about a foot long. The head makes a nice axe...

oh, and even tho its not nesisary, if you heat the bick after you have it forged you can stick in the hole and bend it so when you spin it 180 and rivit it the horn will be level (not at all nesisary)

[carlson]

Ask the Votech to turn the cone on one end W/ shoulder, turn the other to fit the coupler snugly and thread it for a lock nut.

Frosty The Lucky.

Frosty

Is either of these transitions at the back of the horn section what you were referring to when you say shoulder?

Also if I'm able to get it machined would I want to find a bolt before hand or just provide some spec for the threaded end. 

Thanks

[carlson]

I was mostly just joking about peining it like a tenon though it'd work fie. Were I doing it I'd trim it so there's maybe 1/2-3/4" protruding, chamfer and weld it. 9" isn't so long for a horn, I was thinking the knuckle was narrower for some reason and the pics you posted show the relation clearly.

Frosty The Lucky.

Would a mig welder be capable of performing this weld. My brother-in-law does welding for a living and fun. 

Would you weld the cone side as well?

[Frosty]

Shouldered pretty much as drawn though I'd try to have the shoulder match the hole as closely as possible to prevent stress points.

I use my mig for light stuff, sheet or tacking up to 1/4. I'd fire up my Lincoln ranger 9 and run it like it was 1" thick steel. I'm thinking your Brother in law would have to have a pretty serious mig welder but I know of quite a few that'd do the job.

I'd preheat the horn to 400-450f before welding not because it needs preheating but because it'll shrink as it cools for a super tight fit across the knuckle, not in the hole. If the shoulder didn't match pretty closely and have a good flat face to take the tension, things might go south. That's conservative thinking not having any experience with the things or job.  Anywho, the weld has to withstand the tension too and there will be a LOT.

Remember, I've never done this, it's just in my "how I'd do it first time" book of tricks. YMMV!

Frosty The Lucky.

[Charles R. Stevens]

Forging will give gou a longer bick, even if you just forge it roughfly and have the machine shop true it up

[JNewman]

I second the preheat for any welding.  Knuckles and couplers are alloy steel not mild so should be preheated.

[carlson]

My brother-in-law says he can do the 9" portion of 1 3/4" at his work. I'm still going to explore the VoTech angle. May end up with a hybrid machining/forging approach. 

I appreciate any tips/tricks I can get...theoretical or otherwise. 

[Charles R. Stevens]

Forging a blank to be machined is classic late 19th, early 20th century smith work.

[BIGGUNDOCTOR]

I like the turn, and thread approach. You are using mild steel which isn't that tough, so more than likely it will get damaged. Being threaded you can remove it to repair, or replace. Also it would allow you to make several different shapes to install into that hole. Plus if you make a holder so that you can flip it onto its side the hardies will have more utility.

 

Time wise, it wouldn't take long at all on my Monarch lathe with the taper attachment, but then again most people don't have a 18.5" x 54" lathe that weighs 5,200# as a home lathe, and that is my small lathe...

[Jim Kehler]

I've repaired a fair number of couplers, we used FCAW (flux core gas shield) with a 9018 equivalent wire. The couplers were quenched and tempered after the welding and grinding was  done.