Sharpening a roughing gouge

[Prashun Patel]

For years, I have used a v-arm and a bench grinder to sharpen my spindle roughing gouge.

I recently read that the v-arm shouldn't be used this way because it traps the tool and can kick back. Bah! Has never happened to me in 7 years.

A DAY after I read that it happened to me. Thank goodness this was a CBN wheel, because I might have shattered a friable wheel.

Now I am scared to sharpen my roughing gouge this way.

How do YOU do it?
The only way I can think to do it is to set the v-arm loosely. This will provide a pivot point, but will allow the arm to slip in the event that the wheel catches the edge.

[Dave Fritz]

I use a Robo Rest and rotate the tool by hand. I like to soften the corners rather than have a straight end. Glad you were ok. That can be scary.

[Roger Chandler]

+ 1 on dave’s suggestion.....I don’t have a Robo rest, but use the rest that came with my Wolverine jig.

[Robert Henrickson]

+ 1 on dave’s suggestion.....I don’t have a Robo rest, but use the rest that came with my Wolverine jig.

Likewise -- I rest the gouge on a Wolverine platform set at the desired angle.

[Reed Gray]

I took one look at the V Arm thing and said 'On H... No!' Just didn't look right. I have always sharpened them on a platform, which is how I sharpen all of my tools, but I am kind of different....

robo hippy

[Jeffrey J Smith]

By the way, since Reed didn’t point it out, the RoboRest excells here with accurately repeatable settings quickly set in 5 degree increments for platform angles. Mine is the version for the Wolverine base. I woudn’t ever want to have to sharpen without it, and very reasonably priced for a tool that will outlast the turner.

[Mike Peace]

Always use a platform, now a Robo Rest. I had a minor catch with the wolverine arm with AO wheel years ago and said never again.

[William C Rogers]

'
i use to do it with the Woleverine, but now use the Robo Rest.

[JohnC Lucas]

A whole lot of it depends on the angle you grind your roughing gouge to. I grind mine to 45 degrees which is way more acute than most people. With that grind it is pretty safe to use the V arm although I also use the Roborest to sharpen mine. When you grind a roughing gouge in the V arm that has a really blunt angle like many come from the factory you get to close to the center line of the wheel and it can grab the tool and pull it down tearing up the wheel. Sharpening on the platform eliminates this problem. The same is true for sharpening a scraper. Never use the V arm, the platform is much safer.

[Reed Gray]

Hmm, I always thought most SRG's were sharpened to 45 or less degrees.... so, part 2 of this thread would be what angle do you use/prefer? I guess also, there are a number who put a tiny bit of sweep to the nose profile rather than leaving it square/straight across. Most don't go as far as the Continental style more common to the old school bodgers.

robo hippy

[Michael Mills]

Mine is really low tech. I took a piece of angle iron and ground off one side except for a small lip (about 1/8 to fit over the rest on the grinder).
On top I tack welded two short sections (maybe 2" long at the most) of 3/4 angle iron upside down making a V in the middle.
Place in the V and just rotate the tool.
I use a small spring clip to hold it to the grinder rest.

[Dennis Ford]

I use a platform and grind to 45 deg or a little less with the edge straight across.

[JohnC Lucas]

For roughing a large number of turnings like spindle duplication I will regrind mine to about 55 or 60. It holds an edge many times longer and you never chip the edge. I use 45 degrees for my hand mirrors because I can rough the handle and then do a lot final shaping with the same tool and it leaves a finish clean enough so I can just touch up the spindles with the skew and I'm done. Doesn't hold an edge as long but it only takes seconds to sharpen and takes me longer to switch out the spindles. A lot of roughing gouges come from the factory with really blunt grinds. Don't know if that's what they use in those countries or they just figure you will regrind it to your specs.

[Prashun Patel]

I am appalled at myself for doing it the wrong way all these years. Thank you for the info. Will use the rest. That’s already how I sharpen scrapers.

[John K Jordan]

Hmm, I always thought most SRG's were sharpened to 45 or less degrees.... so, part 2 of this thread would be what angle do you use/prefer? I guess also, there are a number who put a tiny bit of sweep to the nose profile rather than leaving it square/straight across. Most don't go as far as the Continental style more common to the old school bodgers.
robo hippy

I'll check my angles when get back to my shop but I'm pretty sure they are 45-deg or less. I sharpen my two Thompson SRGs (deep "U" flutes) straight across so I can use the flats on the sides like a skew chisel. I sharpen a forged continental SRG with a slight radius on the nose since I like how it handles - kind of like a big contental spindle gouge. The others (Sorby, etc) are straight across.

[Dennis Ford]

It seems important to me to note that any type of tool is capable of grabbing the grinding wheel when supported a distance away from the wheel AND ground at a blunt angle. Also that any tool can be ground safely with a jig if ground at a acute angle.
If the grinding angle is above 65 deg, be very careful when the tool is not supported near the grinding wheel.

[Prashun Patel]

Circling back to this. Thank you all. I have my new rest installed and have become comfortable and quick sharpening the roughing gouge (and skew and parting tool) without the v-arm - using only the rest. My skew and parting tools never gave me problems because the cutting edges are very acute.

I suppose the roughing gouge got closer and closer to 90 over time. This is now very obvious to me because each time I reset the v-arm, I was setting it to hit the nose (think microbevel ala flat blade sharpening). While that was always fast, I see now that it makes the angle more and more vertical over time (in my case years), which created the problem.

[John K Jordan]

I finally measured the bevel angles on my roughing gouges. I measured six and they are all between 36-deg and 42-deg.

JKJ

[Gordon Stump]

It happened and scared the crap out of me. The bolts holding the grinder motor were a little loose and angle engaged the wheel too low. The gouge chipped as well as the wheel. I changed the angle and now give it a light touch. I am still spooked.