Need help with the Crown Deep Hollowing Tool

Tim

It does however cut endgrain well. Bob

To me, it looks very similar to the Oneway Termite. They have some good instructions that come with the termite and a great way to sharpen it if you have a router table. As far as usage, Oneway recommends that the open side should be pointing sideways rather than up or down. As you bring the tool toward the inside edge of the bowl, it will rub on the surface but not cut. Then very gradually turn the too so the opening points a little upwards. Do this gradually until you start to get the cutting action. NEVER go into a turning bowl with the opening facing upwards. Real bad things can happen.

This and the larger version are my favorites and I use them more than most of the others put together for hollowing large amounts of material, and then switch to shear scraping for final smooth finish cuts.

The best place to put the tool is dependent on several things: whether you're near the middle of the bowl or several inches out, whether you're working on the bottom of the bowl, a more vertical side area, or underside of a closed form. Usually if you're too high or too low the cap or the angle of the grind will prevent the edge from seeing any wood at all unless you rotate about the axis of the handle, OR rotate the tool by lowering your hand and raising the tip so you can shear off the wood above 9:00.

In my experience it cuts best without catches when the cap is set correctly with a small gap. I usually have a hole barely large enough for the tool to fit in, so the tool rest is always below CL exposing most of the hole, which is more comfortable for my shoulders.

I suspect one trouble point, or learning point, is to realize you don't need or want the cutting edge to be on the front tip, you often, maybe mostly, want it to be skewed to the left or right depending if you're cutting to the left or right, and you have to account in your mind for the tight radius of the tool as opposed to the larger radius of the surface you're cutting...you are usually cutting against one side or the other of your tool's groove.

As I work the area near the top and under the top of a closed form, I get more extreme with the tool handle, dropping my hand and cutting above 9:00 up towards 10:00 or 10:30 at times on the upper inside top of a large closed form, also with the tool rotated to take a skewing shearing cut, but close to the CL is usually the best place.

I think the reason this works well is if your hand comes up, lowering the tool tip, it moves away from the wood. Below the centerline as your hand moves up it will dig in. On the other hand, below the centerline too far the tool shape prevents the edge from seeing any wood at all, so you can creep up on it from below to find that "sweet spot" safely.

The cap limits how far above the CL you can go with the tool and still get any wood too, so the worst is when you have a big gap and come up so far and dig in, then the force pulls your hand up and you get a bad catch.

I find the best technique is to cut one groove and then work the radius of that groove either from inside out or from the outside in, but slicing away layers one after the other, sometimes smoothing the action, reducing catches, by rotating the axis of the handle just a bit. Of course, if you are changing from inside-out to outside in tool path, or vice versa, you will have to stop and put the gap on the opposite side of the tool.

The best way to make cap adjustments is buy a belleville or spherical washer that holds the two pieces gently before you fully torque the screw, adjust the gap with the washer only slightly compressed, then torque it down when you're ready. This difficulty in setting the tip is the only valid complaint I've heard about the tool, and it's a shame they don't supply belleville washers with the rig.

(Other complaints I think are less valid are more "personal preference" and not really wanting or needing the aggressive cut or enjoying the feel of it, or not willing to take the time to learn how to use it well.)

The tool is best presented to the wood with the cutting edge angled so as to take a shearing cut, but is extremely sensitive to the correct gap between the edge and the cap. Sometimes, like when you're way above the center line on a concave surface, the edge is already taking a shearing cut without having to rotate it CW or CCW

Angling the tip correctly takes practice, and depends a LOT on the curvature of the thing you're cutting. I find the place where it switches from easiest going outside-in from 'inside-out' is when you're about 4-6 inches from the CL, 6-8 inches from the tool rest, and the angle of the surface you're cutting is roughly 45-90 degrees from the plane of your faceplate. 0-45 and 90-180 degrees from the faceplate, it's usually easier starting from the CL and working out.

One trick, if you're having trouble and don't want to adjust the gap so much, you can reduce the "effective" gap just by rotating the handle axis in your hand, tilting the left edge of the tool down.

Once there's some volume in the hollow space, go to the bottom of your hole, cut a groove by rotating CW, pushing your hand down (edge moves up into the wood) then PULL the tool toward you and cut into the upper edge of the groove you just cut. This requires the cut gap to be adjusted toward the left & inside edge. You can hog out a lot of material real fast that way.

Don't know if the terminology is clear or not. At these times I wish we could come up with a clear and consistent vocabulary to describe the different curvatures, angles and directions of movement.