Thread: Free hand grinding or a jig

Originally Posted by auscab

Why is it so crucial to have it within 5mm ? like the Carbatec info says 160 to 165 mm in the first paragraph here
https://www.carbatec.com.au/document...structions.pdf

The geometry of these swing leg gouge holding jigs produce swept back gouge grinds with convex edge profiles and this requires a precise relationship to the centre height of the grinding wheel.

Trying to compensate for base-slide heights that vary too much from the recommended height, by for example changing the slide position then adjusting the leg position to re-establish the required bevel angle, can give you some very unusual and usually unwanted results.

Likewise, the recommended tool projection from the holder is part of the design geometry... stick with what is recommended, at least to begin with.

If you do go with the Carbatec system I, and I'm sure there will be others here on this forum, would like to hear how you go with it.

Originally Posted by NeilS

The geometry of these swing leg gouge holding jigs produce swept back gouge grinds with convex edge profiles and this requires a precise relationship to the centre height of the grinding wheel.

Trying to compensate for base-slide heights that vary too much from the recommended height, by for example changing the slide position then adjusting the leg position to re-establish the required bevel angle, can give you some very unusual and usually unwanted results.

Likewise, the recommended tool projection from the holder is part of the design geometry... stick with what is recommended, at least to begin with.

If you do go with the Carbatec system I, and I'm sure there will be others here on this forum, would like to hear how you go with it.

Sounds good Neil . One thing I wasn't really imagining was the convex grind as well as the angles. Its going to be nice to try it out . I ordered the Carbatec set today . I will have to work out a way of mounting part of it to my mini lathe bed grinder and report back .

Rob

Plenty of replies on jigs and and rigs. From my perspective, once you learn free hand you'll probably toss all jigs and use a very simple set up that is free of clutter. Unfortunately grinders run at such high speeds that it's unsettling and makes learners rush so most don't stick with trying to learn free hand. If you did, it'll probably take a few weeks to a few months to get it right, depending on how much time you invest. And a few extra mm off the tools...

Originally Posted by The Spin Doctor

And a few extra mm off the tools...

That’s the part that scares me, given the cost of decent gouges.

Originally Posted by The Spin Doctor

...trying to learn free hand. If you did, it'll probably take a few weeks to a few months to get it right ...

While experienced turners can pick up an irregularly ground bowl gouge and immediately adjust to and effectively use it, the issue for new turners is that they are still learning to turn and irregular and variable gouge profiles are a handicap to grasping and improving their tool technique. Consistent gouge profiles eliminates at least one variable and enhances the novice's progression to competence.

Glenn Lucas told me that he sharpens all of the bowl gouges himself to be used by the students in his classes. By knowing exactly which profile is being used he can quickly see where and why any of the students are having trouble.

Like me, Glenn began turning before jigs became available, so we acquired the necessary skills to freehand sharpen, but he teaches all of his students how to use sharpening jigs having found that a consistent profile avoids roadblocks in their progress.

In the following video he covers the four main commercial jigs (Tru-Grind, Vari-Grind, Tormek and Sorby Pro-Edge), plus (understandably) some promotion of his signature tools and jig setting charts.

Glenn Lucas Woodturning signature tools - YouTube

My grinder now sits on top of a shipping container in the factory and has done for the past 10+ years since moving to our current factory. Prior to that it was in a dark corner of the old factory and only ever cam out for Working with Wood Shows, exhibitions or domos.

However in my 35 or so years of woodturning and carving, I can honestly say my grinder was never used with any special sharpening jigs other than six I was given to evaluate prior to doing a video on sharpening in about 1993. Oh and a Carba Tec wet grinder.

I never kept any of the jigs or wet grinder and can honestly say I really wasn't all that impressed with any of them either. I guess for a novice they would be a help getting bevels right and reasonably even, showroom grinds on gouges, etc.

However in all instances they took longer to set up than it took to grind a few gouges free hand and the bevels were no better than I got with freehand grinding. The one thing I did do was to dispose of the original tool rests on my $20 El-cheapo grinder from Kmart (late 1970s) In their place put a couple of home made, 50mm deep x 100mm (approx) wide tool rest on the grinder which could be adjusted to almost infinite angles for students to grind skew chisels, flat chisels, plane blades, etc freehand, without mucking them up too much.

As for me, I ground pretty much everything freehand and the big tool-rests were used as hand-rests to allow for more comfort and accurate grinding of gouges, etc. Most of my students used the same method of sharpening on a grinder and many had made and used similar oversized tool rests.

I never saw the benefit of wasting 5 minutes or more setting up and sharpening with a jig, as that would be 4 1/2 minutes of lost turning time. Done right I could be on and off the grinder in 15-20 seconds with a newly sharpened tool. Work for a few hours with a couple of quick touch-ups on a slip stone or bench stone with often no need to grind again for another day or more until the concave of the bevel had become almost flat with stoning.

It is something I could do and still can (if needed) although I won't be getting up on top of the shipping container to do it. I always found sharpening tools freehand satisfying and a bit like the dance (flowing body movements) you do when using the tools on the lathe. No dance.... You're not doing it right.

25 years ago most turners would have said freehand jigs and sharpening systems were a waste of time. However I've noticed over the last 10 or so years some of the most vocal opponents to jigs and sharpening systems would appear to have taken them to their hearts I believe that one of the most vocal about time wasting now uses a Tormec and has all but lost the ability to free-hand a clean smooth grind on a gouge.

OK it's just my opinion and it basically goes to the old saying.

When asked: "Can you show me the tricks of the trade?"
The answer is: "Yeah, LEARN THE TRADE!"

As for the Sharpening video. I took a preview of it to 4 working with wood shows and had it running throughout the show and got no interest in it so shelved it.
Tried to run 1 day tool sharpening course one per term for 5 years, in all that time it only ran once when 20 signup. For all the others there was no-one interested.... Not one person.

Cheers

Originally Posted by ubeaut

Tried to run 1 day tool sharpening course one per term for 5 years, in all that time it only ran once when 20 signup. For all the others there was no-one interested.... Not one person.

That sums it up, Neil.

The other issue is, even if there was enough interest in taking sharpening courses, there are few now who can teach and pass on freehand sharpening as a skill. Those who can still competently freehand sharpen (usually those who were turning 25-30yrs ago) are a dwindling bunch, or no longer with us, so there are few that can teach that now.

Soon to become yet another lost art... : ~(

"I never saw the benefit of wasting 5 minutes or more setting up and sharpening with a jig, as that would be 4 1/2 minutes of lost turning time. Done right I could be on and off the grinder in 15-20 seconds with a newly sharpened tool. Work for a few hours with a couple of quick touch-ups on a slip stone or bench stone with often no need to grind again for another day or more until the concave of the bevel had become almost flat with stoning."


No one says that!!! What sacrilege!! Use a honing stone to touch up a turning chisel. You heretic!! All I can say is Amen bruh!!!! Listen to this man, he is a prophet

I use a Sheppach Tiger wet sharpener.
I personally feel that the slower rpms make it easier to use.

Originally Posted by woodhog

I use a Sheppach Tiger wet sharpener.
I personally feel that the slower rpms make it easier to use.

I agree with the slow grinding makes it easier . Take it slow and easy and accuracy jumps right up . For a long time I've felt 2850 rpm bench grinders are roaring away much to fast for delicate shaping of some tool steel jobs .
I made a special chisel for cabinet work years ago . A bolting Iron. There was a bit of involved shaping with it after the basic shape was sorted . I ended up finishing it with an old hand cranked bench grinder . Slow and easy . Holding the chisel in left hand while cranking with the right hand . It gave me very accurate results . That is also how I have been free hand touching up turning chisels at the lathe for years . I sort out angles on the 2850 al oxide + the linisher next to it , and use the crank grinder which is fitted to the top of my wood turning chisel cabinet to re sharpen after that till it needs grinding again .

This is the Bolting Iron I made .

A Bolting iron

I use it when fitting locks in tight spots quiet a bit . It takes a belting and hasn't failed which surprises me now because welding HSS on other tools has failed for me so fast sometimes . It just falls apart. This tool holds its edge and stays together .

Originally Posted by NeilS

That sums it up, Neil.

The other issue is, even if there was enough interest in taking sharpening courses, there are few now who can teach and pass on freehand sharpening as a skill. Those who can still competently freehand sharpen (usually those who were turning 25-30yrs ago) are a dwindling bunch, or no longer with us, so there are few that can teach that now.

Soon to become yet another lost art... : ~(

Wow!! Do I feel old now LOL