I've made somewhere in the neighborhood of 150 chisels now. I show a lot of tools, but I don't talk too much about process because who really cares. I am bonkers about being competitive with consistency and making a chisel that will outlast anything commercially offered in regular work and sharpen as easy as anything of similar hardness.
Which means water hardening steel. You can minimize warp with water hardening steel, but you can't eliminate it reasonably and chase high hardness.
One of the things that I dread is that in the process of making the chisels, everything is done mostly flat, the bolsters are forge welded on and then heat treat is after that. On more modern chisels (not seaton type) the bevels are ground on freehand with hands on the chisels so you can get a sense of where the temperatures are. In manufacturing, you'd push this relationship some - grind temperature vs. tempering, but I don't like that. It takes probably five minutes more on a chisel to grind bevels almost all the way down in great volume with the right grinder (a belt grinder).
But the post heat treat bottom truing is a huge pain. The belt grinder platen will get things close, but there's a tiny belly bias in all directions. It takes something like 10 minutes of hand flattening on a sandpaper lap and then working up through, and I've been thinking about getting a potters table to modify the disc and put abrasive on. But I just don't really feel like committing to that.
When looking at current diamond prices based re: the "which diamond hone" thread, ebay served me a 10 inch diamond disc. These are popular in 6 inch sizes (too small for this, especially with parers, and 8 inch, but I haven't until recently seen one in ten inch size....
....$33 shipped for a 320 grit very good quality electroplate disc, 10 inches in diameter.
There's another too with the hand lapping - once you get coordinated, there's going to be a problem with heat. More than there is with a power grinder. I've drawn temper on chisels before and blistered my fingertips.
Initially, I thought I'll wait until an idea comes to mind to rig up some stationary lower speed rotary table, but the figured before doing that - I've got some long-ago purchased leather wheel thing (that sucks) that had a drill arbor...
......which perfectly matches the diameter of the hole in the diamond plate. And another from the past, an 8" MDF disc, which who knows what I intended - probably some delusion about using the thing on the lathe for glazing chisel (too fast, too hot).
We'll see how long this lasts, but the setup doesn't allow you to apply a lot of force (good, the hone will last longer, and I can make up for the light pressure with increased speed). The speed control on the drill is good, so you can keep the speed relatively low, but far faster than you could dream of doing by hand, and the flatness is "go right to india stone" after done, and almost no heat.
And no need to occupy space with some big contraption.
the heat becomes an even bigger issue with the seaton style chisels as they're only about .06" thick at the ends, and I really don't have interest in making them fat for heat treatment and then grinding all of the thickness off after the bottoms are done. That's dumb.
A second trial with this thing on an overhard chinese HSS iron, and something that would take a very long time to do by hand was into uniform flatness within about two minutes.
I'd be more than happy to pay a dollar a chisel in tooling costs to use this instead of being stingy with PSA roll.
This is sort of a dumb cheesy fix, but it was effortless more or less instead of just jumping immediately into trying to create some large "super accurate" stationary setup like a potter's wheel. It would also work and last a long time to grind primary bevels, but I've got no interest in using it for that.
it also cuts a very fast primary on a knife , which may be useful in grinding knives (grind knife, establish bevel to check to see where it's uneven and then final grinding work brings it into uniformity in size from end to end), but the crystolon in the IM 313 does that just as well and is a little bit more accurate.
Which means water hardening steel. You can minimize warp with water hardening steel, but you can't eliminate it reasonably and chase high hardness.
One of the things that I dread is that in the process of making the chisels, everything is done mostly flat, the bolsters are forge welded on and then heat treat is after that. On more modern chisels (not seaton type) the bevels are ground on freehand with hands on the chisels so you can get a sense of where the temperatures are. In manufacturing, you'd push this relationship some - grind temperature vs. tempering, but I don't like that. It takes probably five minutes more on a chisel to grind bevels almost all the way down in great volume with the right grinder (a belt grinder).
But the post heat treat bottom truing is a huge pain. The belt grinder platen will get things close, but there's a tiny belly bias in all directions. It takes something like 10 minutes of hand flattening on a sandpaper lap and then working up through, and I've been thinking about getting a potters table to modify the disc and put abrasive on. But I just don't really feel like committing to that.
When looking at current diamond prices based re: the "which diamond hone" thread, ebay served me a 10 inch diamond disc. These are popular in 6 inch sizes (too small for this, especially with parers, and 8 inch, but I haven't until recently seen one in ten inch size....
....$33 shipped for a 320 grit very good quality electroplate disc, 10 inches in diameter.
There's another too with the hand lapping - once you get coordinated, there's going to be a problem with heat. More than there is with a power grinder. I've drawn temper on chisels before and blistered my fingertips.
Initially, I thought I'll wait until an idea comes to mind to rig up some stationary lower speed rotary table, but the figured before doing that - I've got some long-ago purchased leather wheel thing (that sucks) that had a drill arbor...
......which perfectly matches the diameter of the hole in the diamond plate. And another from the past, an 8" MDF disc, which who knows what I intended - probably some delusion about using the thing on the lathe for glazing chisel (too fast, too hot).
We'll see how long this lasts, but the setup doesn't allow you to apply a lot of force (good, the hone will last longer, and I can make up for the light pressure with increased speed). The speed control on the drill is good, so you can keep the speed relatively low, but far faster than you could dream of doing by hand, and the flatness is "go right to india stone" after done, and almost no heat.
And no need to occupy space with some big contraption.
the heat becomes an even bigger issue with the seaton style chisels as they're only about .06" thick at the ends, and I really don't have interest in making them fat for heat treatment and then grinding all of the thickness off after the bottoms are done. That's dumb.
A second trial with this thing on an overhard chinese HSS iron, and something that would take a very long time to do by hand was into uniform flatness within about two minutes.
I'd be more than happy to pay a dollar a chisel in tooling costs to use this instead of being stingy with PSA roll.
This is sort of a dumb cheesy fix, but it was effortless more or less instead of just jumping immediately into trying to create some large "super accurate" stationary setup like a potter's wheel. It would also work and last a long time to grind primary bevels, but I've got no interest in using it for that.
it also cuts a very fast primary on a knife , which may be useful in grinding knives (grind knife, establish bevel to check to see where it's uneven and then final grinding work brings it into uniformity in size from end to end), but the crystolon in the IM 313 does that just as well and is a little bit more accurate.
