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Gouges, Part 2  
Spindle Roughing Gouge

By far the best way to learn to use a gouge is to enlist the help of an experienced turner, someone who can guide you along, keep you out of trouble, and, not least, true up a blank so that you begin on a smooth surface.  The helper can also check the grind on your gouges; very few come from the store ready to use.  

Because this may not be convenient or possible, I’m going to try to explain how to use gouges as if you have no prior knowledge of them and are working alone.  In case I’m not successful, keep the lathe RPM fairly low and wear a face shield.  

I think the logical place to start is with the spindle roughing gouge (SRG).  You can do a lot with it, and it’s fairly forgiving and easy to use.  It is used primarily for turning spindle stock from square to round, or truing up a section of a limb.

Let’s get started.  Mount a piece of practice wood about 10” long on the lathe between centers.  This can be a section of the trunk of a small tree or a limb as long as it’s fairly straight and free of sizable knots.  Don’t use a piece larger in diameter than about 3”.  If the bark is still on the piece, be aware that pieces of it may fly off.  That’s why you need the face shield.  

Another option is to split a short length of a “2x4” down the middle and practice on it.  Just don’t use treated lumber, ever, as turning stock because of the nasty stuff it contains.

Set the tool rest about 1/2” away from the piece, parallel to the ways of the lathe.  Set the height so the cutting edge will be at center height when the tool is tilted about 10º.  

Rotate the piece by hand to see that it clears the rest, check to see that the lathe is set to about 800 RPM, and then stand to the side and start the lathe.  If everything seems in order, turn the lathe Off and prepare to make a few shavings.  

The bevel of a SRG is ground straight across.  The corners at the ends of the bevel are well forward, and the tool can be positioned so that a corner could possibly contact the spinning wood.  Do not let this happen.  Keep the corners well clear of the wood.  

With the lathe still Off, position the tool on the rest as shown in the following photo and drawing.  That is, at about a 20º angle to the axis of the lathe with the handle tilted about 10º.  This should put the bevel in contact with the wood, which you can verify visually.  If your test piece still has the bark on it with its uneven surface, the situation will be confused a bit, but you can get close enough.

Rotate the lathe by hand and you should get a small shaving.  If you don’t, adjust the orientation of the tool until you do. Only a very small adjustment should be required.  Once you get a shaving, or some cutting action if you’re working against either bark or the corners of square stock, note the orientation of the tool.  This is where it should be when you present it to the wood with the lathe running.

The photo at right was taken during an actual cut. The cutting action occurs slightly to the left of the centerline of the tool, which gives a shearing cut. Also, the shaving is fairly narrow.  The motion was stopped by using an electronic flash.

If the workpiece is out of round, not centered perfectly, or if it is square, you must not push the tool against the wood. If you do, the tool will move in as the low point of the piece travels under the cutting edge, and a heavy cut will occur when the next high point comes by. Once a shallow cut is established, simply move the tool along the tool rest parallel to the piece and the high points will be reduced.  In due course, they will be removed as the piece becomes round and runs true.

Your turn.   Start the lathe. Orient the tool on the rest as you determined it should be, then move it forward to engage the wood and establish the cut.  Slide it sideways to continue the cut down the side of the workpiece.  Go a short distance and then stop.

Turn the lathe Off and check the depth of the cut.  It should be only 1/8 to 1/4”.  Is the cut deeper where you stopped than where you started?  If it is, you may not be rubbing the bevel, or more likely, you just need to guide the cut as it progresses.

How to guide the cut.  You steer the tool by moving the handle either left or right a small amount, changing the angle the tool makes with the axis of the lathe.  Moving the handle to the left will cause the cutting edge to gradually climb out of the cut as the tool advances.  Moving the handle to the right increases the depth of the cut.

After your initial success, keep on successing.  Practice, practice, practice.  Concentrate on making the cut with a smooth, fluid motion along the piece.  For fun and as a test of your ability to guide the cut, form a series of waves in the surface, just because you can.  

Make the same cut in the opposite direction.  To do this, just switch the angle of the tool so that the opposite wing contacts the wood.  Also rotate the body so the flute will face to the left, as opposed to facing to the right as it did before.  With the lathe Off, place the bevel in contact with the wood and note the orientation of the tool.  Then start the lathe and proceed to make a cut.    

Approaching the work straight on.  So far I’ve recommended that the body of the tool be placed at about a 20º angle to the axis of the lathe, but you are not limited to this.  As long as you keep the bevel rubbing, the tool will work over a wide range of angles, even when the body is at right angles to the workpiece.  

However, when you approach the workpiece straight on, the cut will no longer be a shearing cut, and the surface left by the tool will probably not be as good. Also, you can get into trouble by taking a cut that is too wide, where you may lift a shaving almost a half inch in width. For experienced turners this may be acceptable, but until you get that experience, the safest practice is to keep the tool at an angle to the work.  

Rotate the tool.   A SRG brings a lot of cutting edge to the task, and only a fraction of it is used at any one time.  By rotating the tool, you can use a different part of the edge, to spread the wear around and postpone the trip to the grinder.  However, keep the corners of the bevel well away from the wood at all times.

A major precaution.  No doubt you have heard that a SRG should (or must) not be used to rough out the outer profile of a bowl.  Here’s why.  

The wood fibers in a spindle are oriented parallel to its long axis.  For the most part, the wood is removed by cutting or pulling the fibers apart at right angles to their length.  This is the weak direction in the wood.  The sideways connection of one fiber to another is not very strong.

However, a traditional bowl (not an end-grain bowl) has two regions where the wood fibers are oriented perpendicular to the surface and where the wood can be removed only by cutting the fibers straight across.  This is the stronger direction in the wood, and the difference in strength is substantial.  End grain is much harder to cut.

The trunk of a small tree may also have significant areas of end grain where limbs were growing from the trunk.  These areas, of course, are the knots.  The same holds true for a limb with a protruding branch. These must be approached with caution, which is why I suggested that your practice piece be “free of sizable knots.”  

The other part of the story has to do with the construction of a SRG. The gouges are forged from flat stock instead of being milled from a round piece, and they have a tang that inserts into the handle.  The junction between the tang and the body of the tool is the weak link. It is not as strong as the round shank of a bowl gouge.  

Now the stage is set.  If you’re truing up a bowl blank with a SRG, twice each revolution the cutting edge will encounter the end grain. Further, suppose you’re taking a heavy cut with the tool more or less straight on to the surface, and to make matters worse, the blank is not true. Corners left by a chainsaw stick out and impact the tool with great force, perhaps multiple times per revolution.

In such a case, the tool may break, and it will break where the tang enters the handle.  

This is a bit hard to imagine, but apparently it happens.  To date, I’ve met only one turner who has been a witness to such an event.  The cause:  heavy-handed turning on the outside of an out-of-round bowl blank – with a spindle roughing gouge.  

Up next:  The basic cut with a bowl gouge.