Several years ago I bought a starter lathe and a cheap set of turning tools, under the (misguided) assumption that for something as basic as cutting a spinning piece of wood there wasn’t any difference between high end and bottom of the barrel. With time, I’ve come to understand that mistake, and slowly I find myself acquiring more items of better quality so that I can be certain my screw-ups are due to my own poor technique (which I can improve on) rather than limitations of my tools.
Regardless of the quality of the turning tools, there will come a point where they need to be sharpened. The set I first bought needed a full sharpening procedure right from the start as their factory grinds left much to be desired, in some cases not even reaching the edge of the tool. I am fairly adept at sharpening flat tools, but my first attempts to sharpen on an old, underpowered 5” narrow wheel bench grinder were dismal failures. That gave me an excuse to upgrade to a standard 8” Ryobi bench grinder, and I managed to bring the tools into something resembling a proper cutting edge, though my freehand technique needed lots of practice. I did find the stock rests on the grinder to be a bit small and hard to adjust, and the one on the left side had a trough, ostensibly for drill bits, that made it useless for anything else. As I acquired better turning tools, I hesitated to try and sharpen what were already very good grind profiles on the grinder and instead spent far more time and effort using diamond files to touch up the edges.
I recently needed to sharpen some garden tools on the grinder and needed to use the left side, but the rest was so limiting that I gave up and began looking for aftermarket rests. That was when I came across the Oneway Wolverine lathe tool sharpening jig. I had seen it before when I was looking for ways to better sharpen the lathe tools, but had decided then that it was a touch too expensive for me and I would eventually make my own jig if I didn’t get the freehand technique down. What sold me on it this time wasn’t so much the lathe tool jig, but the included flat rest accessory. It was large, solid, and easily adjustable, perfect for addressing the limitations I had found with the stock grinder rests. And it “included” a turning tool jig…. While I was at it, I also bought the Vari-grind 2 and skew jig attachments in order to have a complete set.
The concept of the jig is very straightforward. Two mounting blocks are rigidly attached underneath and in alignment with the grinder wheels, one under each. A section of square steel tube fits in the block with attachments at one end (a V pocket for the turning tools, a riser and adjustable angle flat plate for the flat rest). Using a simple lever actuated cam lock located within the mounting block, the square tube can be locked at any point along it’s length so that the attachments can be placed exactly where required. Since the square tubes are identical in profile, changing from one to the other wheel is as simple as releasing the cam lock, sliding the tube out, sliding it into the other base, and then locking it in the desired position. The only difficulty with this is that a means needs to be provided to ensure that the grinder and the bases remain in alignment with each other. I did this, as per their directions, by using a scrap of ¾” plywood and mounting both the grinder and the bases to it
I had thought that aligning would be best done by using a square to reference off the front edge of the board and give parallel guides, but then found that the base casting of the grinder wasn’t uniform enough to make this approach feasible. Instead, I mounted the grinder as close to parallel with the front of the board by trying to keep about a 1/8” gap between the edge of the grinder wheels and the edge of the board, then used clamps to secure the mounting blocks while I visually aligned the longer V pocket tube at it’s max extension with each wheel in turn. It wasn’t 100% precise, but certainly within the tolerance stack of the complete system. One item of note – when screwing the mounting blocks to the board with #8 x 1” construction screws, for which the mounting holes are pre-countersunk, the outer shields of the grinding wheels were in the way. I got around this by using a long ¼” drive wobble extension with a suitable socket at the end to hold the screwdriver bit, much easier than disassembling the grinder to gain the required access.
To test it out, I clamped the baseboard to a worktable and grabbed a spindle gouge that needed sharpening after a combination of a poor initial grind and multiple attempts to correct it freehand. The profile was non-uniform to start with, which made my freehand attempts to fix it even harder than it should have been, and the result was an odd profile with a very uneven bevel – making the tool nearly impossible to use properly.
Starting the sharpening process was as simple as selecting the desired wheel (I had heard that the stock wheels on the Ryobi grinder were not the best for this use as they tend to grind hot, but not having another wheel on hand I opted for the finer of the two stock wheels), installing the V pocket arm, dropping the base of the tool into the pocket, and adjusting the length until it was sitting at the desired bevel angle. Given that I didn’t have a clean bevel to start with, I simply set what looked like a reasonable starting point based on what was already there.
Next the tool is removed, the grinder turned on, and the tool replaced, slowly and rather gently allowing the blade to come in contact with the wheel. Once contact is made, a simple twisting motion on the gouge is all that is needed to get the job done… but it is a little harder to do than it sounds. Not much, but it’s worth practicing the first few times with something other than your best tool to get the hang of it. The key thing I found to be useful was to apply very light downward pressure with the base of my palm on the tool shaft to keep it well seated in the V-pocket and concentrate on keeping the contact point on the center of the wheel while I twisted. In focusing on doing this, while also trying to reshape the edge into the desired profile, I ended up staying just a touch too long on the corners and overheating them despite frequent cooling dips.. which gave me an opportunity to practice a bit more. After a few more tries I had the hang of it, and the next few gauges I sharpened took me about 3 minutes each – with much of that time spent waiting for the grinder wheels to come to a stop between gauges so I could check and set the initial position of the jig for each new tool. After a quck touch up with a diamond file to remove the slight burr on the non-ground side, all of the gauges were better than they had ever been in my ownership.
After grinding and deburring:
With the gouges done, I turned to the skews. A few turns of a clamping handwheel attaches the skew guide to the V-pocket (and it can also be left on for regular use of the V-pocket), and it’s ready for use by dropping the skew into one of the offset V-pockets. The setup technique is roughly the same as for gouges, e.g. put the tool against the wheel and adjust the length until the bevel is as desired. When grinding, however, a different technique is used. Rathar than keeping the contact point in the center of the wheel and twisting the handle, for a skew the blade needs to be aligned parallel to the wheel, then lowered to touch and gently slid side to side across the width of the wheel, keeping the blade parallel. Again, it takes a bit of practice to get the hang of it, but once done a few times it’s fairly easy.
I did not need to sharpen any of my bowl gauges, so the vari-grind 2 attachment has not yet been tried out… but I’m expecting it will be the same process of a couple of practice runs before getting comfortable with it.
All in all I’m very satisfied with the jig. It’s well made, easy and quick to use, and with the included flat rest actually improves the general capability of the grinder rather than limits it as some jigs have a way of doing to the tools they are mounted on. Yes, it’s a touch on the expensive side relative to low-end turning tools, and with enough practice at freehand sharpening functionally equivalent results can possibly be obtained, but for now my higher end tools won’t be going anywhere near a grinder without the jig.