I'm trying to make a trapdoor casting work. drilled hole in door hinge with #49 cobalt drill bit then cut shank off to use as hinge pin. Neighbor tigged it in place worked ok for a minute then broke.I have 1/16 welding rod, would that make a good pin? If not I need a recommendation that would work better.please!

Welding rod should work. I keep a supply of O-1 drill rod stock in lots of sizes to use for things like that, as well as HSS drills. What may have happened to your first pin, heat from welding over-hardened it, making it brittle.

Yes, go with the drill rod. Welding rod is soft. But that really shouldn't matter; not like you are opening it 50 times a day. Or a lifetime.

yes It got brittle and I won't be opening it a lot, but I want it to last. Going on a 52 win sporter I have been working on for ever , going to hide extra magazine in there with 5 cartridges ,(" HOPE, MAYBE) will look around and see what else I have, would shank of common drill bit work?sorry John I re-read your answer and you answered about the drill bit. Getting to old for this stuff.

Don't over think it.
If you can get any remains of the old overhardened pin out of the #49 size hole, just use a pin of most any steel that fits firmly in the hole.
Trim to length and either soft solder in place or use a dab of LocTite to hold it in the hinge portion.
It only has to sit in place and turn with the door open and close. There's no pressure from the end(s) to push it out of it's spot in the hinge.

Another old drill bit shank will work fine. A shank from a broken HS drill bit,,usually plenty of those available as scrap.
Heat/anneal them blue first and they cut pretty easy.

Drill rod,,Welding rod,,misc pins and parts from disassembled guns and other mechanisms,,
Lots of common items around most shops to make a simple pin out of that isn't expected to perform NASA spec duties.

thanks for the replies. started to j-b weld it . like the idea of not using heat. have heard black max is good. again thanks for the replies and kind advise.