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Fred Oliver
06-24-2008, 11:30 AM
I say to myself, "Duh! Why didn't you do that sooner?"

Every single time!

So how do you know when it's time to grind?

I notice on the videos Raffan feels the edge of the tool every time he picks one up. It seems to be a habit, and I'm not sure what it means to him. It doesn't mean much to me, as I'm not really able to tell much about the edge of a gouge by feeling it.

I usually go to the grinder when I notice that I'm getting sawdust instead of chips, when the gouge seems hard to move through the cut, or when I'm getting a rough surface.

Since I suck at grinding, probably grind too much, hate the multi-faceted bevels, hate to waste tool steel, and ALWAYS wonder why I didn't refresh the edge sooner, I'm probably not grinding often enough.

And that's, I'm sure, a false economy, considering the cost of sandpaper and the time, energy, effort and fingerpads wasted.

So how do you know when to grind?

Paul Heely
06-24-2008, 11:41 AM
I sharpen when the tools does not cut like I want it to. I don't know how else to explain it. I've found that with time I've become more aware of how the tool is cutting and can tell that the cutting action has degraded to the point that I need to sharpen. I sharpen my gouges using a jig so I get a nice consistent grind and really don't grind much metal at all to touch up the edge.

--
Paul

Steve Schlumpf
06-24-2008, 12:08 PM
Fred, I use the Wolverine system with a jig for my gouges and the easiest way to explain when I sharpen is when I start to apply pressure during the cut. Normally (with a sharp gouge) all I do is guide the tool. Soon as I start to push the gouge - its time to sharpen.

Harvey M. Taylor
06-24-2008, 12:19 PM
I bought the Tormeck wet grinder with the right jig, spacer and projection gauge and all those problems went away. I could sharpen the Irish grind blindfolded if I had too. Sure it is kinda expensive, but who said woodturning came cheap?

Richard Madison
06-24-2008, 12:37 PM
Fred,
The tendency in the beginning is to grind TOO much. To resharpen a tool use a very light touch. You need remove probably no more than .001" to produce a fresh, sharp edge. The touch will come to you in time, as well as the feel for when to sharpen. Sometimes when one is focused on the workpiece, there is a time lag before you hear your brain say "Oops, we need a fresh edge on this tool".

Reed Gray
06-24-2008, 12:51 PM
I have gotten into the habit of feeling the edge of my gouges each time before I use them. For me, I use scrapers for all my roughing, and the gouges for clean up. If I do a shear cut, I will use the scrapers as well. I do have a number of gouges that I sharpen all at once. Some times I can't remember which gouge I was using, so I have to test it to see. Maybe some times I will remember to put the dull ones off to the side rather than back in the pile.

Tool steel makes a difference in how long they stay sharp. For plain HSS, I would rough it out, then sharpen for the final cut. This is for both the inside, and the outside of the bowl, even if the bowl is only 6 inches in diameter. With the harder steel, specifically the Thompson gouges, I can finish cut several large bowls before the edge needs to be resharpened. If I was roughing out a large bowl with the Thompson gouges, I would still touch up the blade before making the finish cut.

Think of it this way, one minute on a bowl (10 inches plus at 800 rpm or so) is about 2,000 feet of shavings. That is a lot of wood to go over the edge of your tool.

robo hippy

robert hainstock
06-24-2008, 1:43 PM
It is certainly a subjective thing, and I think Steve S solution is as good as any. The only tool I was ever sure of when to sharpen, Is a chainsaw. When the tanks is empty, sharpen it. :eek::):)
Bob

Judy Kingery
06-24-2008, 2:27 PM
Fred, I second Reed's suggestion - I do the same thing, feel the edge of my gouges before I use them. And I tend to sharpen several at a time so if one dulls, I'll reach for the next one during a session. Best to you, Jude

Mitchell Cholewinski
06-25-2008, 12:24 AM
Harvey
I use the Tormek and the projection jig same as you. It works wonderful if you use it right but enter the human factor and even this excellent system can be used wrong. I always sharpen the sides of gouges first and then got in a bad habit of rolling from one side to the other several times, to sharpen the point. Pretty soon the point got too rounded. The tool was sharp as the dickens but would start to cut fine then violently fly back to the left and create gouges etc. The problem that developed was the point was too round. You need to keep the point in a very v type shape. Do this and the problem disappears and you have the finest cutting tool available. I use the grinder also with the Wolverine jig but this doesn't compare to the Tormek with the projection jig. With my gouges sharpened like this I can finally use the sides of the gouge to do scraping cuts that are unbelievable. They give skew type results. If any of you guys are having trouble with your gouges violently flying back to left as you cut, try this your gonna like it. Mitch

Jim Becker
06-25-2008, 7:38 AM
You do get a feel over time, but if you are getting itchy about the cut, it's already been too long. You need to go more often during those finishing cuts, too, than you do when doing general turning. On spalted pieces, for example, about 30 seconds of shear cuts requires a trip back to the grinder. David Ellsworth lines up about 8 identical gouges for that all sharpened up and goes through them one at a time for just a few seconds of turning before abandoning the tool for a sharp edge...and no sanding afterward. I only have three, but have done essentially the same thing to keep on turning longer between grinder steps.