Timeless Wood Turnings, Roughing Out Bowls

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Roughing Out Bowls

I like to rough out green (wet) wood to the basic shape I want then allow it to air dry or season. I find it is a good way to get what I'm after. It gives me some days of roughing out which makes a mess everywhere and some days of refining and finishing.

These demonstrations are geared more towards woodturners and use a vernacular that is understood in the art of woodturning. (Explanations are in italics and parenthesis). I get a lot of questions as to how I take a large log and make a bowl from it. I regret that as of yet I do not have a video but the pictures tell a pretty good story. This wood was sealed as soon as it was cut down, in April and is fairly heavy with moisture.

Both of these demonstrations create a Natural Edge (the bark left on and exposed) in each piece. The first piece is done with a Faceplate orientation (the grain running perpendicular to the lathe). The second piece is with a Spindle orientation (the grain is running parallel with the lathe).

Click on images for full size	End Grain-Natural Edge Roughing Out a Side Grain Deep Bowl
	This Chilean Mesquite log was about 12" wide and about 13" in length. The Spindle capacity of the Lathe I'm using is 14" so there isn't much clearance. I wanted to use the whole log and wasn't worried about the inclusion of the Pith (the very center of the growth rings, not always the center of the log). This log presented a couple of options for me. A flat topped hollow form like a sideways D with a dome on top, a wider natural edge bowl with a nice flat circular rim or a taller necked bowl. I ended up going for the taller bowl because the unusually flat top side here would result in a nice circular rim without much divergence.
	In preparing the Blank (wood cut to be turned) I first found the center of it using Dividing Calipers. This was a visual center according to where I wanted the rim to be and the length of the blank. Next I used a Bandsaw and cut off the corners. I wasn't equipped to make rounded cuts with an unstable Blank and safety dictated straight ones. Also here I used a wide flat Chisel and Mallet to remove the bark and get down to solid wood for the Spur Drive (drives the wood using spurs and mounted in the lathe) and the Tail Center (ball bearing cone supporting piece from tailstock of lathe). Pounding the Spur Drive into the Blank helps set the spurs or teeth into the wood. Always use a wooden Mallet for this job.
	In this demonstration I am using a JET, 14" x 42" VS PRO Wood Lathe which has a swiveling Headstock (the drive side of the lathe). This is not my personal Lathe, it belongs to a shop I am using and since I don't know who used it before me I checked the center alignment of the Headstock and Tailstock (idling side of the lathe, captures pieces between centers). This is a good practice for any Lathe in which the Headstock is allowed to swivel or slide. Ensure the Headstock and Tailstock are tightened down prior to checking alignment. Use a straight Spur Drive and Tail Center.
	Here the Blank is mounted between Centers. It would not clear a full hand rotation so I had to use the flat Chisel and pare away the offending parts in five different areas. This is where the circular cutting on the Bandsaw would have been nice but was easily overcome. Always rotate a piece by hand to see if it will clear a full rotation prior to starting the Lathe. The Banjo (mounts on lathe bed and holds tool rest) had to be positioned all the way against the Headstock to clear the blank. The Tool Rest (T shaped post mounted in banjo that supports tools) barely cleared the widest part of the Blank. I mounted it so the top, on the left, would be level which made it a little more eccentric.
	Using the slowest speed available on this Lathe, 450 RPM, I pre-started it by hand rotating it so the Spur Drive wouldn't spin out. Even though this lathe weighs 356 pounds, the eccentric Blank wobbled and walked the Lathe all around! My goal here was to get it to round and eliminate the heavy vibration. I also needed to get the Banjo to clear the blank before I could move the Tool Rest over as I had reached the end of it.
	Clearance from center to the top of the Banjo is 5" or a is 10" diameter. Here you can see the Banjo is under the Blank. The fresh cuts are on the right and almost ready to move the Banjo over again to work on what will be the bottom of the bowl. You can also see the end of the step cuts or ridges I use when turning. Leaving these ridges gives a quick place to pick up a cut when Riding A Bevel (placing the tool's bevel against the wood to control depth of cut). The vibration went away about 3 cuts into this portion.
	The Blank is now mostly rounded and not vibrating at all. I kept the speed at 450 due to the size of the Blank. Constant attention to the Tailstock was required. With the vibration, the Spur Drive kept digging deeper. Without adjusting the pressure from the other end the Spur Drive would have spun out possibly requiring a new mounting technique.
	About 9" in diameter at this time and rough shaped. The bowl did not look right with tall sides so a gentle curve just under the rim will give the eye something to fill the space with. I will refine this in final shaping after it is dried, following the golden thirds principal. The Tenon has been formed at what will be the bottom, for remounting in a Chuck (self centering, scrolling, 4 jaw chuck). In shaping the outside, cuts were made from the right to the left or Downhill so that the grain was supporting each cut. This eliminates Tearout (wood fibers being ripped out instead of cut cleanly) which can be a problem with Green wood.
	Here the bowl has been turned around and remounted by the tenon that was cut on the foot or base. I defined where I wanted the Natural Edges to be on the rim and began the hollowing. I did use the Tailstock to support it as I initially cut through the bark. I cut in about 3" and widened each cut by about 3/8", again leaving steps or ridges. Again, I find the ridges make it faster to pick the cut up again when I'm ready to go deeper.
	About halfway down into the bowl here. I'm concentrating on leaving a clean surface so I don't have to worry about cleaning it up once dried. Even though this is a rough turning and I already plan to return the bowl, I may prefer to leave the inside or outside alone at that time. Leaving a clean surface means less work later. Every few minutes I stopped and tightened the Chuck. As with the outside, the green wood was soft and needed just a hair of tightening.
	The final depth of the rough turning is reached here. The inner circle there is where the wood was already drying. I reached my depth first, intentionally, and brought the rest of the bowl into a thickness that agreed with the depth. You may not be able to see in this photo but the sides are fairly smooth and what appear to be ridges is wet verses dry wood.
	This is the final rough shape. I used two gouges in the roughing of this bowl. Mostly my 5/8" Ellsworth gouge and secondly a 3/8" bowl gouge that has a grind which allows me to get at the flat bottoms. I used the Grinder about 10 times during this whole process to touch up the tips of the tools and keep them sharp. If this were dry or seasoned wood it would have been four or five times that. In a few months of Arizona's dry climate it should be ready for final turning. Mesquite does not move much as it dries so I shouldn't lose too much getting it back to round and sanding it out..

Click on images for full size	Side Grain Deep Bowl Top of page Roughing Out an End Grain Natural Edge Bowl
	This Blank was sliced off from the side of the Blank above. As you can see by the Tape Measure it is about 11 1/2" at it's widest point. I could have used the same orientation as above, cut it from top to bottom as we're looking at it here and ended up with a couple of nice vases. I chose a different path! I used a set of Dividers to determine the center of the Blank, then adjusted away from the smaller lobe to help balance the piece. The Pith in this piece is well off center and won't be an issue.
	Using the adjusted center, I attached a Faceplate (used for mounting blanks to a spindle) to what will be the top of this piece. Note that I am using all screw holes available. The screws are mounted into end grain here and I wanted all the support I could get. This will be a Spindle orientation with the wood fibers running parallel to the Lathe bed. This is also called an End Grain Bowl.
	The Blank is mounted to the Lathe and the Tailstock is brought up for support. There is just enough room for the Banjo in between the Blank and the Tailstock. Because the top and bottom of the Blank are not in the same plane or not coplanar, I expected to have more wobbling than normal.
	The wobbling was minimal and is gone at this point with enough material being removed. As in the last bowl, I do not plan to go faster than the minimum speed on this Lathe, 450 RPM. The cutting direction is from the outside in or downhill. Again, this uses the remaining wood fibers to support the cut. Cutting uphill can lift fibers up, leaving a rough surface.
	As I cut in, I'm beginning to play with a shape I have in mind. I'm going for a rounded bottom with a reverse curve towards the outer lip. This time I'm leaving a Natural Edge on the outside of the lip instead of the top. On the top of the Blank you can see some bark hanging there. That is torn wood as opposed to a clean cut. That means it's time to resharpen!
	The final rough shaping cut has been made on the outside. The tenon for remounting in a Chuck is also done. This branch inclusion, the dark spot, appeared from what looked like a tiny nublet in the previous photo. Very interesting grain almost like a burl.
	The Blank has been wiped with a sealer to keep it from drying too fast and remounted in the Chuck. I had the room to make this bowl taller but the flow of the curve looked better with a shallower form. Just because you have more wood doesn't mean you need to use it!
	Ready to start cleaning up the face and then bring up the Tailstock. If you look back at the progression of photos you will see where the bark has been flying off. An issue I'll have to deal with later!
	Hairy cuts!!! This side of the Blank was like night and day. You can tell by the chips and dust on the Lathe as opposed to nice long curlings as before. I had already resharpened my tools twice at this point. The wood was not happy!
	Deeper shaping of the inside and the wood was happy again with nice wet curls coming off the gouge! The bark wasn't happy though. I was using a freshly sharpened fine point gouge and the bark still lifted. I may end up removing all of the bark because it doesn't look right. I think the bark problem was because this tree was cut in Spring when moisture was traveling up the trunk and the bark was swelled. The best time to harvest trees for turning purposes is in the winter when moisture is out of the wood.
	The final rough shape. The support cone in the center has been removed. The flow from outer edge coming inward dips nicely into a bowl. The dark spot is the branch inclusion which I flooded with CA glue for support. The uneven bark is already an eyesore to me. The rough edges of the bark can be clean up but I'm not going to spend 20 hours gluing bark back on like a jigsaw puzzle! Looks like it will become a Bare Edged Natural Bowl!
	Side Grain Deep Bowl End Grain Natural Edge Top of page