Welding for another reason

[easygo]

I bought a set of old ring chains and modified them to fit my tractor. I bent the rings to match the curvature of my tires and added extra teeth to make it a smoother ride. All that work turned out real well except that the new "teeth" I added to the rings are wearing very quick. They are just run of the mill mild steel and the original teeth are clearly some far more wear resistant material. My idea is to add a harder surface to the new teeth by welding a bead on the very top and then dousing with a some water, to try to harden the weld but not the entire tooth. Is this going to work? I know I can buy hard facing rods but they are expensive and I have a bunch of 6013 that I never use.

ps: The chains are way too heavy duty for my tractor but they sure work well for yarding out firewood. I will post pictures in the next day or two as the chains are behind a bunch of other stuff for Summer storage.

 

[Shield Arc]

Another approach is to use a torch to heat the work area to a cherry red in dim light and then dunk the heated part in oil. (An open gallon of motor oil is fine.) Polish a few spots to reveal clean metal and reheat slowly until you see the bright steel areas turn to a light straw color.

 

[mrmikey]

.....welding a bead on the very top and then dousing with a some water

Won't work, you can't appreciably harden mild steel by quenching it, not enough carbon.
Best solution since you already have the corks added is to hardface them. Hardface rods aren't cheap but you do get quite a bit of coverage from them. Just remember, use the lowest heat that'll will give you good fusion with the base metal as you don't want to dilute the hardface rod, it isn't going to look pretty
I find the Stoody 31 to be one of the better hardface rod, good for abrasion (which is your major concern) as well as impact. It's what I use on buckets and such with good results, probably in your case 5/32" would be a better choice or if you're not used to a larger size 1/8"....Mike

 

[LD1]

Another option is to get some 7014 rod and use it like a hardface rod. It isnt going to be as hard/wear resistant as hardface rod, but a 70 series rod will probabally be harder and more wear resistant than trying to heat/quench mild steel. And the 7014 lays on like butter very similar to 6013 and just as cheap

 

[Shield Arc]

Don't disregard heat quenching so easily! I do it to chisels, center punches, and chipping hammers.
I know a lot of people who like to use used motor oil, they say it adds more sulfur.

 

[20 20]

Don't disregard heat quenching so easily! I do it to chisels, center punches, and chipping hammers.
I know a lot of people who like to use used motor oil, they say it adds more sulfur.

I'll 2nd or is it 3rd this

 

[easygo]

Thanks for the ideas. I only have a stick welder so heating with a torch is not an option. The other problem is that after my modification the chain became a unit. I mean I welded links on the big rings that connect them laterally as well so they can't "wonder around" on the tire. So. Since the chains weigh around 60-70lbs per side I have no option of heating and then picking up the unwieldy mess and plunging it into water or oil. I have a total of 28 lugs to heat treat or just simply build up with a bead of weld. I guess if I can't do a satisfactory job I will just have to bight the bullet and get some hard facing rod. I have to produce a total of about 60-65" of welds. I have not forgot the picture just had no time yet.

 

[Gary Fowler]

If you dont want to invest in hard surfacing rods, just do a weld metal build up on the worn area with whatever rod you have on hand. When it wears off, build it up again. Depending on how fast the wear cycle is, this base metal build up might last a long time.

 

[dstig1]

Chisels, punches and hammers are made of hardenable steels, not mild steel. Steel is hardened by carbide precipitation which requires excess carbon. Mild steel just doesn't have enough carbon content to harden much if at all.

 

[Shield Arc]

Chisels, punches and hammers are made of hardenable steels, not mild steel. Steel is hardened by carbide precipitation which requires excess carbon. Mild steel just doesn't have enough carbon content to harden much if at all.

You are correct:thumbsup:, I stand corrected!

Scroll down to "Mild and low carbon steel".

Then on down to "Case hardening".
Carbon steel - Wikipedia, the free encyclopedia

 

[Gary Fowler]

Even though mild steel cant be hardened doesnt mean that welding rods wont harden when applied. I once had a machinist ask me to run a "hot bead" around a coupling that was on a piece of cold rold steel for deep penetration as he was going to machine it out flat and remove the surface weld. I ran a hot bead using 3/32 6010 at about 150 amps and gave it back to him. A few minutes later he came back and wanted to know what I had done as the weld was breaking his cobalt cutting tools it was so hard. I had to take a rosebud and heat the whole piece up to about 1250F and let it cool slowly to anneal the weld metal enough for him to machine it. I guess the high amps and the quick quenching of the weld metal on the solid rod did some sort of hardening on it. I do find that a high amp 6010 rod is much harder than running low amperage for some reason. There is no addition of carbon to it, but it does harden.

 

[easygo]

If I do end up buying hard surfacing rods, are they easy to restart? I only have to put down 1.5-2" long beads at the time and then restart on the next "tooth" . Also. Roughly how many inches of weld can I get out of one rod? I know it depends on the "travel speed" but any rough estimate? Is it similar to 60xx or 70xx rods that I could try how much hard surfacing rod I would have to have to do this project?

 

[LD1]

I have never had any trouble with re-starting. But if you do, it will most likely be like 7018 where they glaze over. If they do, I'd have a separate peice of steel laying there (ungrounded) that you can tap/scratch the rod on before each restart.

As to the lengh you get out of each rod, that depends on how long you hold/build up. But IMO, they weld like any other rod, you can go fast for a light buildup, or take you time (consuming more rod) for more build-up.

In your case, I'd go about at a normal pace, try not to burn too deep into the base metal (and dilute the hard material as you or someone else already mention), and then if you want more, do a second pass.

Either way, once you buy a box, you will get a really good feel for then within a rod or two. But nothing is out of the ordinary. They are like running any other rod IMO.

 

[Gary Fowler]

You want to run them pretty cold to prevent dilution of the weld metal for maximum hardness. With a 1/8" x14" rod, I would think that you could get at least 9 or 10" of weld metal as you would just drag it and pretty much let the rod burn inch for inch. Brain55 has done lots of hardfacing so his advice might be pertinent for you.

 

[easygo]

Thanks for the great advice. I will follow the guidelines and will look into prices since it sounds like I would not need more then 8-10 electrodes. It might be worth coughing up some extra $. Also. Are these hard surfacing electrodes supposed to be kept like 7018 or it doesn't matter so much?

 

[Jesse masterson]

I'm not saying this works cause I never tried it but I read an article on net about someone who mixes a cup of Calgon dishwashing liquid and dip the steel in it something about the bubble action. It harder steel all through it from a hardness of 35 to a hardness of 48