Cheesy Toolmaking Improvement - but Effective

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D_W

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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).




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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.
 
Also, an interesting coincidence that derek was talking about using a (6"?) version of these discs to keep his wife's knives in shape. Presumably without them spinning?

probably just a coincidence that they showed up on ebay and not related to cookie crawlers saying "matches something else this guy read". I had concern about the smaller lapping machines with longer chisels as I'm guessing I'm not done making parers.

If anything, the odd request out of nowhere usually involves parers and "can you make it with a london pattern handle" or seaton chest chisels (the latter only because nobody really offers them at retail).

If the wheel is small, it can accidentally grind a step further up the back

Throwing $33 at one of these maybe once or twice per year may sound stupid, but figure each set of chisels consumes a ceramic belt ($6-$7) and probably $60 in steel and wood for handles, it's just a welcome to wear things out by actually making something rather than imagining that they could wear out and thus avoiding doing anything.

There is no perceptible difference between the quality of this disc and a diamond hone, though - and the plate s flat and can be affixed to anything else that's flat. It's not flimsy or warpy a I expected it might be. It's a lot of real estate for $33 with shipping and for anyone thinking of maybe doing something like this to grind primary bevels, there are versions at least as coarse as 80 grit, and then finer from here.
 
One last separate thought about this--

If you buy vintage tools and have thought about flat rotary stones like the makita grinder, or wished there was something like it, If you can keep the speed down like this drill can (to avoid diamonds from being vaporized by sparking from the steel, though I guess you could find CBN versions of this), this is a seriously good option to do initial back flattening of old chisels and plane irons. it is what the makita would be.

it's also suitable for creating a setup for machine planer blades (at relatively low speed), which I'll be trialing it on later today, and on a hard card scraper, I can confirm that it eliminates the need for a file (freshened the edge on one of the AEB-L scrapers last night).

building some kind of cheeseball fixture with UHMW plastic feet supporting the disc would not be hard if my drill in one hand and item being ground in the other sounds too risky. You can apply kerosene or WD40 to this thing and keep the speed below "slinging it" level without too much trouble.
 
I got a Worksharp as a present about a half dozen years ago. I tried some of tge diamond discs Dave referenced, on it. They worked, by life was not that great. I didn’t spend much time trying to refine it, as freehand sharpening was much quicker.
 
I got a Worksharp as a present about a half dozen years ago. I tried some of tge diamond discs Dave referenced, on it. They worked, by life was not that great. I didn’t spend much time trying to refine it, as freehand sharpening was much quicker.

My thought with the machine in general was too fast and too small diameter.

I'm good with the idea that this thing is basically turbo glorified sandpaper and will settle into slowness and probably just end up getting thrown out. My bar is the "buck a chisel" thing for initial flattening because my sandpaper use is probably half of that and it's a miserable process.

I never got tempted by the work sharp - but there was that and the lap sharp, which was a higher quality version of something similar. The work sharp looked like something that would've had potential if it was just a better tool in general, but if it was, it would've also cost $1000.

this disc itself, even if it slows down, is too aggressive in my opinion for secondary bevel sharpening. It's kind of like a big disc with honing compound on when you want to strop just a little refinement (btdt).

...i just check aliexpress and there are tons of vendors selling these discs, with (pricey) options up to 20" in diameter.

I ordered two more in other grits to try - they end up being about $28 each.

I forgot earlier that my initial thought with the 80 disc is that it might be slightly faster, but there will be deep grooves left behind by it. which is true.

I ordered one, anyway, to see if it has merit worn in a finer state once its worn.

For anyone else reading, the merits here are mostly for toolmaking - not suggestion much experimentation with this if you're sharpening things aside from the potential for something like the 8" squares ore 8" discs. The surface itself is a 1mm machined steel platen and for lapidary purposes, there would be a master platen that it attaches to. Too thin to be used without attaching it to something.
 
You need a viceroy sharpedge to mount your diamond disk to 🙂
No idea on its speed though.
 

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