Thread: Two questions from a newbie

Kind of a noob at bladesmithing, just bought my first HT oven a few months ago and haven't done any major bragging rights projects since then cause I want to build a twin grinder before I get serious about anything. But I have never had a problem grinding down to .05" prior to HT and I have USUALLY been okay down to .04" but under .04" thick, I lose too many in the quench. Two batches in a row, I lost 3 for 3, pushing the limit to see what I could get away with. If you are a metric kinda guy stay at about 1.25mm or thicker pre-HT is my rec.

My first razors were major Gold Dollar regrinds and stock removal razors I made out of vintage through-hardened files. (modern imported files seem to be all case hardened, no good for grinding out a razor.) Didn't take long to realize that the more grinding I could do on annealed steel and the less I had left to do on hardened steel, the less time wasted and the fewer belts or wheels worn out. My first "barbecue grill" razors were from a couple of those old files and the process went a lot quicker. Now I got a bunch of O1 and 1095 pieces waiting to be turned into razors and stock removal, sure. That's how I roll. But everything gets almost down to final grind before HT and edges will be in the .04" to .05" range.

I have heard of guys going even thinner but I know my limitations. I don't have the expertise for that.

After quench, you can thin the blade as much as you want before honing, as long as it doesn't get too flexy. The thinner the better, up to a point. It is good to leave a "backbone" in the blade just above where the bevel will start, for a little more rigidity, but if it is too close to the edge it gets incorporated into the bevel and you have a wide contact area which will in extreme cases make honing more difficult and time consuming. A super narrow bevel is a joy to hone if you know to use a very light touch. A backbone allows you to go just a teensy bit thinner and still have a razor that will still stand up to normal use and pressure.

The razor can be a LOT thinner than any knife you have ever made. And so, you need to be very careful when finishing with power tools. Talking about the body of the blade, not just the edge. Thin steel overheats really quick, really suddenly, and the Blue Stain of Death will shock you with how suddenly it can appear on steel this thin. Once you are at final thickness you can forget about annealing and requenching. Color change = dead razor. R.I.P.

No fancy thermostatically controlled HT oven? No proper forge, either? Plenty of razors have been made in fire pits or barbecue grills, with a piece of pipe taped to a hair dryer for draft, and a magnet and eyeball for judging temp. Failure rate will not be so bad once you have done a few razors. Anneal, grind, normalize, maybe grind some more, HT and quench, temper in a toaster oven and bobs yer uncle.

I hate wedges, but they are probably a lot easier for a beginner. You might try a quarter hollow. I wouldn't try a full hollow. In fact I have never tried one yet.

Good luck, and have fun!

Thanks to everyone for all the help. I got two rough ground and heat treated today. I’ll try to get some pics up later on.

Everything went well in the quench. I was pretty nervous but no cracks and no warps.

I figured since I was trying something new I might as well try my hand at bringing out a hamon. I haven’t etched them yet but the edge skates a file and the spine is still soft so hopefully I get something.