Thread: Bowl Gouge sharpening problem

You're either using the wrong angle on the jig or the wrong length of tool projecting from the jig. (Or both)

For that gouge profile you should either use a basic rest and simply "roll" the tool along it's axis to get a conventional "square end" grind (what I think they call a european grind now?) or use a steeper angle on the jig to get more of a lady-finger profile.

I don't mean the bevel angle at the tip - that's alright. I mean the angle the tool is held in the jig; you should be managing something looking more like this pic from off the Tormek site.

they are bad.

try doign it by hand.

its surprising how accurate you can get if you know how.

slowly rotate the tool as you push it up the wheel.

What you are doing is starting with the tool flutes upright then sweeping either left or right this causes the centre to get ground more than the sides.

Start with the flutes pointed to either 10 o clock or 2 o clock and sweep to the opposite side what this does is give you an even grind over the whole tool. then you do the same the other way, you should only need to do this 2 times any more and you are wasting steel.

Thanks for the replies. I'll have to have another go at it tomorrow...hopefully

I find the best way to sort out jig settings is to use a tool of the same diameter and with a profile that you want to copy. You may have one, if not beg, borrow or steal one.

With the grinder NOT RUNNING play around with the settings until you can get the tool profile to follow the wheel.

Then and only then start up the grinder and grind the new tool.

When you have worked this out and are happy with the shape, record the settings for future reference.

One point to remember is that with the tool in the jig you still need to watch the shape and grind where it needed to make/keep the fingernail profile.

Putting black texta on the bevel makes it easy to see where you are grinding.

I had a dream the other night. I had invented a machine that I could walk up to, poke a gouge in a hole, and on removing it had had a perfect fingernail on a very sharp gouge.

Dream on guys, it don't exist.

Using a jig is still a hand/eye cordination skill.

Hope this helps.

the jigs exist but they are probably harder to use than free hand. i use a slow speed grinder with a fixed toolrest set at bevel angle i want . took time but easy when you have it . cheers bob

Thanks again for the tips. I remembered that I have a Tormek jig (so to speak) for sharpening scrapers. This is exactly like a tool rest that I have seen used for freehand grinding.

I will set that at 45° and do a freehand grind on the Tormek wheel...worth a try...got to be better than the result I'm getting at the moment.

As said above, the jig only determines the grinding angles, and the degree of difference in angle between the tip and the wings for a fingernail grind.

YOU have to control the SHAPE of the profile, by controlling how much you grind where.

Further, the shape of the flute on bowl gouges has a great influence. Typically the P&N gouges I use have a fairly "U" shaped flute, which is very prone to the problem you describe, and I grind aggressively in the "high" areas to compensate. Some other brands, like the Glaser, have more of a "V" shape (parabolic) which is less problematic.

regards

I had a bit of a win in my fight with the bowl gouges. I took all the advice on board and it was all helpfull. As a few have said I still must control the shape...the jig and the grinding wheel are good for a quick sharpen up and a guide.

So I ground the gouge into the shape I thought it should be using my standard bench grinder, then used my tormek to "Fine tune" the shape and I believe I am close to it being right.

Only thing now is to do a tiny bit of work on it tomorrow and try it out on a lump of timber.

I foolishly thought I had one of those machines that Tim mentioned...place the gouge in the jig...place the jig on the grinder...turn the grinder on and a couple of swivels of the jig and HEY PRESTO...NOT SO....I have learnt a valuable lesson in sharpening.

Again thanks for the help.

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