Case hardening points

[DC]

I'll give it a shot

[Greybuff]

You would be better off using canola oil, it's not as toxic and gives a faster quench. You want the oil at about 100 degrees if you live in a cold climate or your steel can crack(ask me how I know). If you haven't done any forging or welding on the 'points' you only need to heat it up to a non critical temp  (a magnet won't be attracted to it at that temp) one time, and then get it into the oil as fast as you can. Once you've done that, clean em off and put in a preheated (450 degrees) oven for 30min and then into the oil again as fast as you can get it there. This should give you a chisel hard point, provided the steel is heat treatable. Not all steel will harden. If it won't harden than you can contact me and somewhere I have a formula for a solution that will case harden mild steel.......good luck.
Paul

[DC]

It didn't work. I fact I think it's softer. Nails must be very low carbon. I think all I did by heating it was take out any work hardening that the nail had in it.

[Josh B]

That sucks!  Works like a champ on cold rolled steel.  I didn't think it got much milder than that stuff.  Sorry about that.  I didn't mean to waste your time.  Josh

[DC]

Not a waste, I learned it won't work I may try a few more things like brine, maybe with ice in it. Maybe a Slurpy would work.

[Urufu_Shinjiro]

Maybe I could drive a concrete nail though a small washer and then build up brass using the washer as a shoulder, hmmmm

That could work, or you just reminded me I read somewhere on here about just using threaded rod, tightening two or three brass nuts against each other and just grind that into a bullet point.

[DC]

I would then be looking for hardenable screws. I'm not sure if that would be any easier.

[DC]

A few prototypes made from masonry nails, 10 cents each. Bottom two are a washer driven on and then attempted buildup of brazing. I haven't picked up an oxy-acetylene torch for over thirty years so they may improve a bit. I couldn't build up any amount of brass. Top one is a couple of nuts driven on and then brazed. A lot easier to do. I chucked them up in a drill and rounded them on a bench grinder. I have a chunk of mild steel I tested them on. I tried to drive them into it with a hammer. A duplex nail just rounded over and made no mark. These masonry ones stayed sharp and punched a dimple like a centre punch. Now to decide if they are worth the effort. I'm sure with a bit of practice I could turn out a dozen in less than an hour.

[penderbender]

I like the looks of that top one! Cheers- Brendan

[bronco611]

why go through all that trouble? just buy some case hardened bolts that are the same diameter as the nails and completely threaded, then buy a handful of hardened nuts that fit the bolt. add nuts to get the desired weight one nut over expected weight. and grind to a point being careful to not heat it .dip in water to cool while grinding, these should hold up just fine.

[DC]

Sounds good but I haven't seen any case hardened bolts (I'll keep my eyes open though) and if the hardening is just surface by the time you put a point on it you would have ground through the hardening and just have a mild steel point. By point I'm talking about the last 1/8" or so. Of course it all depends on the depth of the hardening. The nuts wouldn't have to be hardened. I'm using aluminum now and it show no sign of deforming.
And it's no trouble, this is just a back burner project that I putter away on while I'm waiting for bows to rehydrate or dehydrate.

Thanks for the input

[jeffp51]

I use brass nuts counter tightened on threaded rod, and then ground down to a point on my belt sander or bench grinder--  3 8-32 nuts and about 3" of rod give me a tip of 125 grain.  they hold up really well i the targets I shoot.  the arrows always break first.

[bjrogg]

Those are looking good DC. I'm sure you'll pick up the brazing in a hurry. I'm thinking grade 8 bolts would be hard enough. I not sure how small they make em. I know you can get 1/4". Your concrete nails look good to me. Bjrogg

[willie]

I'm thinking grade 8 bolts would be hard enough

or at least have enough carbon to be rehardened if not hard enough already.

please post if you locate a supplier of any size smaller than 1/4

there are also various hard self drilling specialty screws for sheet metal and lighter plate applications that you might be able to run into thicker brass or aluminum with a pilot hole.

[Urufu_Shinjiro]

I like all three of those DC.