Grinding Angles

M

michdad

Joined
Apr 24, 2007
Messages
1,091
I am learning to grind, and have a quick question about angles. Is there a standard angle(s) that knife blades need to be ground to, to enable a knifemaker to properly heat treat/finish a piece of steel and get a nice result? :confused::o:confused:
 
Nope. Angle varies with the thickness of the steel, type of grind (flat, hollow, convex) and how high you want the grind from edge to spine.
 
I am just starting to learn the art (head ache?) of grinding blades. The first project I have in mind is a "Chisle shaped Chopper" in a matching set of 3 blade lengths....9, 12, and 18 inches. I am starting with a 4x36 belt sander, a few pieces of O-1 and A-2 for blades, and a few blocks of 1018 for dies and learning to grind. Would I be wise to grind die angles to what my Lansky bladeholder is angled for?
 
I freehand and to me that's the best way to learn. Start with a 45 degree on one side (for a chisel grind, all the way to the opposite edge). Then start decreasing the angle from the edge to the spine (spine gets closer to the belt). As you do this, the bevel on the blade will rise up towards the spine. Go slowly and evenly. Keep the heat down by quenching in a bucket of water by your grinder often. If you are beveling both sides, go to a 45 on one side to within about a 1/32" of the center of the steel thickness. Then move to the other side and do the same (leave 1/16" on the center line). Now, as you grind edge up, you can keep that edge off the belt and start moving the bevel up the side of the flat. Change from side to side after a few passes and check frequently to keep them even. As your grind gets higher to the spine, you will get a good flat. When you get close to the height you want to the spine you want, keep that angle and start removing the steel along that same line to get it to a full flat from top of grind to the edge. Leave about a dime thickness on the edge prior to heat treating. After heat treat, grind lightly to thin out the edge to the desired thickness (I usually go to about about 1/64"). You can exchange grinding at some point to using files if you want to, this helps to slow down the process and get the flats nice and even (file from ricasso to the tip). Best thing you can do is find a knife maker near you that would be willing to show you a few things or get some books / videos off of eBay or Amazon.
 
Hi Mich - I agree with everything Erik said above, the bit about seeing a local maker being one of the most important imho.

I freehand grind and have never tried to do it with with preset angles (although I considered it when I started out). If you end up making more than the three knives you want to do now, you'll want to learn freehand as well. There are so many styles and shapes of knives that you'd end up spending more time fabricating blocks than making knives.

I wanted to add that I started with a 4x36 and I have to say it's painful to grind a 1/8" thick, 4" long blade on one. I say go ahead and try it out, but an 18" knife will take days except maybe if you're doing a scandi grind. If you're taking your grind up more than 1/4", it'll be very slow going on knives that big. I'd personally start out with something a bit smaller and I'd do it with a file.
 
Thanks for the advice guys. Acrid, Your comments about size and grinding blocks, I am already starting to learn that the hard way! What looked simple on paper turned out to be much harder in reality. I do have steel cut to length (1/4 thick!) and guess I'll just have "suffer" as I venture into the world of knife grinding. Guess I am going to get alot of practice huh?!
 
You must log in or register to reply here.
Back
Top