Hawaiian bowls, or ‘umeke lā’au, could look easy to create. But with elegant curves and a semi-enclosed form (the partitions slope inward towards the rim), they symbolize a good “reach” aim for turners seeking to develop their software and design abilities. ‘Umeke are the right marriage of pure kind and wooden determine, and this text describes my typical workflow for crafting them.

Apart from adjusting for measurement and depth, the strategies for making many ‘umeke are comparable. A kū’oho, proven within the opening picture, is a good starting bowl. An iconic kind, it’s wider than it’s it tall. This traditional bowl has an accessible form and presents fewer software-dealing with and sanding challenges than deeper ‘umeke.

Choosing and Cutting the Log

The majority of ‘umeke are turned endgrain. Hawaiian woods, with their deeply coloured heartwoods and lighter sapwoods, have the right distinction for creating sapwood “islands” on the bowl sides. Many non-Hawaiian woods don’t have this distinction, although walnut does and could be a superb selection. It can be not obligatory to have contrasting sapwood and heartwood; different woods, corresponding to ash, with distinct progress markings, are additionally appropriate. The markings can create patterns that simulate the impact of a sapwood island.

Examine the tip of the log. If the heartwood is irregular or oval-formed, measure the narrowest heartwood cross part. Add about 20 % to this measurement to find out how lengthy to chop the log. As an instance, if the heartwood circumscribes an 8″- (20cm-) diameter circle, add 1-5/8″ (41mm) to that and lower the log to a size of 9-5/8″ (24cm). This will produce a clean lengthy sufficient to create a form with good proportions, to permit a little further size for making changes to the rim and backside, and to kind a tenon for mounting the bowl in a scroll chuck.

Finding the center between heartwood and sapwood for a turning blank
Choosing the turning facilities inside the heartwood at each ends of the log is essential to ending up with sapwood on the bowl’s aspect.

The instance proven on this article is made out of milo. As with many bowls turned from moist wooden, it’s good observe to tough it out and let it season earlier than ultimate turning.

Marking Centers

Measuring out turning blank axis with a template
The writer makes use of a circle template simply smaller than the heartwood space to find the axis factors.

Keep in thoughts when marking the facilities that you simply ideally need the roughed-out cylinder to have a heartwood heart surrounded by equal quantities of sapwood. To mark the facilities on the log, I exploit a circle template that’s a little smaller than the heartwood and heart it inside the heartwood on every finish of the log. Note the scale and form of the heartwood. Frequently, it’s bigger and/or asymmetrical on one finish of the log. The finish with the bigger heartwood diameter ought to change into the highest of the bowl, as this orientation will guarantee all sapwood is faraway from the rim space and, by the turning course of, the sapwood islands will probably be positioned towards the widest a part of the bowl. At the rim, it’s simple to show away the sapwood since kū’oho have a pretty shallow slope and the sapwood and heartwood sections are thinly separated.

While marking the highest heart is essential for correctly finding the sapwood islands, the underside heart placement is much less essential as a result of the huge backside curve assures a sharp intersection between sapwood and heartwood.

If the log form itself is asymmetrical, you will need to account for that when deciding the place to mark and mount the facilities. In this case, the log has a bulge on one aspect, so I modify the highest heart very barely towards the bulge. I could make larger changes on the backside of the bowl to keep away from eradicating an excessive amount of sapwood. If there may be a concave part, mark and mount the middle away from the concave aspect of the log.

The sapwood sample ought to begin under the rim and stay pretty centered on the widest a part of the bowl. Sapwood patterns that run off the rim and/or splash too far down the curve will compete with the pure kind and have a adverse influence. Marking facilities with a giant crosshairs makes it simpler to see the facilities whereas mounting and helps gauge modifications if changes must be made to the turning axis.

Roughing and Shaping

Making adjustments to bowl blank axis at the start of turning
Turning the clean principally spherical however not absolutely true offers precious insights into the position of heartwood and sapwood. Make essential changes to the axis factors now, earlier than turning an excessive amount of wooden away.

Mount the log between facilities with the highest of the bowl on the headstock aspect. For this sized bowl, I exploit a 1-1/4″ (32mm), 4 prong drive heart and a heavy-obligation stay heart with a level and cup. Start by roughing the log to a cylinder, however don’t utterly true it up but. As you go, decide whether or not the heartwood will stay centered. Also, sight down the size of the clean and guarantee a good stability between the sapwood and heartwood on the widest half. To obtain this final result, it could be vital to regulate the turning facilities.

Turning Hawaiian bowl blank with a bowl gouge
With the wooden’s pure options aligned as he needs them, the writer completes the tough-turning.

At this level, the piece is just not but a clean cylinder however must be utterly rounded on the rim, the place it’s simple to see whether or not the heartwood is centered. With uneven heartwood on the rim, you may by accident flip away all of the sapwood whereas attempting to realize the rounded kū’oho kind. If the rim heartwood is centered however the sapwood/heartwood stability is off down the size of the bowl, it could solely be essential to make changes on the tailstock finish. If the heartwood is just not properly balanced on the rim, the mounting factors at each ends could must be adjusted. Once the clean is in its ultimate mounting axis, set up the rim diameter and reveal the sapwood sample splashes, which is able to affect the ultimate kind.

Turning Hawaiian bowl blank with a spindle-roughing gouge
He works first with a giant bowl gouge, then with a spindle-roughing gouge.

Because the clean is just not but absolutely trued, I start roughing the cylinder with a 5/8″ (16mm) bowl gouge. This limits the software contact and helps to reduce the software bounce that may occur with a roughing gouge. Turn the pace as excessive because the unbalanced clean will safely permit. It shouldn’t be shimmying round, however a little bit of vibration is suitable. Make peeling cuts to true the tailstock finish and tough in a tenon and shoulder on the underside for remounting. A bowl gouge with a deep V-formed flute works properly at gradual speeds to step lower by the off-heart mass and kind a coarse cylinder. When the clean is healthier balanced, examine the tailstock tightness and enhance the pace. I exploit a giant spindle-roughing gouge to true up the cylinder.

Carving out rim in Hawaiian bowl
At the headstock finish, the writer makes use of a bowl gouge to outline the rim diameter and true a part of the endgrain face.

Lay the roughing gouge on its aspect with the deal with low to cut back the rim space with peeling cuts. As the shavings peel away, search for indicators of penetration into the darker heartwood. Once the heartwood begins to point out within the rim space, it’s time to change to the bowl gouge and lower the rim by truing the tip of the clean.

Turning exterior of Hawaiian bowl with a spindle roughing gouge
A spindle-roughing gouge is used to proceed shaping the bowl’s exterior profile.

Once the rim is established, it turns into obvious what must be turned away on the widest a part of the kū’oho, and I can mix the rim into the higher curve of the vessel. I even have a good indication of how the underside curve have to be adjusted to reach on the completed kind.

Smoothing exterior curves on Hawaiian bowl turning

I do the ultimate mixing of curves utilizing the roughing gouge on its aspect, taking feather-gentle uphill (climbing) cuts. The uphill path resists the tendency for slicing grooves into the wooden.

Previewing the final shape of turned Hawaiian bowl
It pays to look at your progress on the shape with out the toolrest obscuring your view. This traditional Hawaiian kind options sides that slope inward towards the rim.

Before committing to the ultimate kind, pull the toolrest away and think about all the form. If you look at the shape with the toolrest bisecting the form, the shape tends to look barely longer and leaner than it truly is.

Hollowing

Hollowing Hawaiian bowl using a coring setup
The writer makes use of a coring setup to take away a  cone-formed block of wooden effectively. You may additionally accomplish the hollowing utilizing typical endgrain hollowing strategies.

With the bowl mounted in a scroll chuck and supported by the tailstock, I start hollowing by coring, which is an environment friendly approach to take away wooden and create room for software entry. Of course, conventional endgrain hollowing strategies of drilling, then utilizing gouges or hollowing instruments could possibly be used as properly.

After I’ve cored a cone-formed block, there may be nonetheless a lot of wooden to take away, and I desire the massive, deep-fluted, V-formed bowl gouge for this process. This versatile gouge doesn’t clog, presents numerous methods it may be offered to the wooden, and readily adjusts to various slicing necessities. I get clear cuts and exact steering by compound curves utilizing bowl gouges for endgrain hollowing.

Determining proper thickness for Hawaiian bowl
Reduce the partitions to your required thickness for drying. A sidegrain bowl would name for a thicker-sided tough turning than what this endgrain bowl requires.

I tough-form the within of the bowl by forming “steps” to approximate the within curve. I lower from the middle out whereas sighting down the surface form to offer me an concept of how a lot wooden I must take away. I can simply take away half of″ (13mm) of depth in a single go if I start every step lower with a clean entry. The heavy slicing load, together with the bevel stress exerted towards the headstock, tends to maintain the gouge engaged within the lower and dampen vibration. With this lower, I take away extra materials from the rim right down to the widest a part of the within, then change to a 3/8″ (10mm) bowl gouge to refine the within form and outline the wall thickness.

Carving interior of Hawaiian bowl
The writer first cuts from proper to left, then superb-tunes the floor with an inward push lower.

The smaller bowl gouge is my favourite software for slicing in areas delicate to vibration and chatter. It cuts with little or no pressure in opposition to the bowl wall and responds shortly to modifications in slicing angle and stress. I wish to sight alongside the surface form whereas slicing to information me in gauging wall thickness. Then I lower with the flute dealing with up, from rim inward. I shave the wall down from rim to the widest a part of the curve.

I regularly examine the wall thickness to confirm that I’ve a good line and do a ultimate cleanup on the curve utilizing gentle cuts or shear-scraping. The wall thickness is now a little over 3/8″, and I’ve left a little further thickness on the widest half to permit for mixing into the underside curve. Milo is a secure wooden and, since this piece is turned endgrain, 3/8″ is thick sufficient for drying and end-turning later.

Checking interior cut depth on Hawaiian bowl turning
A easy gauge set to the specified inside depth, utilized with the lathe off, signifies how a lot materials nonetheless must be eliminated.

Next, I take a depth gauge and set it to my desired inside bowl depth. I depart the underside thicker than the wall, someplace round 5/8″ or barely extra if I’ve punky areas across the pith to restore. Using the bowl gouge, I excavate the underside part, alternating between step cuts that peel from heart out and again once more to the middle.

Close up of a bowl gouge ground with a short bevel
A bowl gouge with a very brief bevel floor practically straight throughout is helpful for making supported backside cuts.

I now have completed the higher curve going from the rim to the widest half and have established the depth of the bowl. At this level, it’s simpler to see how I need to lower the underside to mix it with the higher curve. The backside curve tends to be probably the most problematic space due to the transition from endgrain to facegrain. It must be lower from the middle of the underside by the transitional space to mix in with the higher curve. For this lower, I exploit a half of″ bowl gouge floor virtually straight throughout with a flat and pretty brief bevel. This gouge maintains good bevel contact throughout flat cuts throughout the underside. I begin with a push lower from heart to left, up and thru the transitional space, and slowly roll the software into a pull lower to proceed into the higher curve. I do the ultimate cleanup and mixing with an armbrace software fitted with a teardrop-formed scraping cutter.

Making cleanup cuts in Hawaiian bowl with bowl gouge
A gouge with swept-again wings and a longer bevel wouldn’t preserve bevel contact throughout these cuts.

The wooden remains to be moist, so I set the bowl apart to season for a few weeks in a heat space away from transferring air. In drier areas or with completely different woods, the partitions could should be thicker for profitable drying. If you might be turning a sidegrain ‘umeke, there will probably be a lot of warping, so the tough-turned wall must be thicker.

Finish-turn the Outside

Soaking bowl bottom with lacquer to stabilize wood
Since the bowl is turned endgrain, the log’s unstable pith stays within the backside. The writer soaks the softer, crumbly fibers with thinned lacquer to stiffen the world.

After the bowl has dried, I see there are cracks and a crumbly space on the pith that have to be repaired earlier than I can end-flip. It’s simpler to deal with this kind of restore when it’s nonetheless attainable to mount the bowl on the lathe. Since I’ll be utilizing a vacuum chuck for end slicing the surface backside of the bowl, it’s vital to seal any cracks or punky wooden. I soak the questionable space with lacquer sanding sealer thinned with an equal a part of acetone, which is able to penetrate the wooden and harden the comfortable fibers. This combination received’t depart a plastic residue that may intrude with sanding and ending and can forestall the attainable staining from cyanoacrylate (CA) glue.

Filling gaps in Hawaiian bowl turning with scrap wedges
He then glues in wedges to fill the gaps.

I put together wedges to fill the crack and faucet them in firmly sufficient to compress the comfortable fibers within the crumbly space surrounding the crack. Soft fibers which might be nonetheless damp from the lacquer sanding combination will stick collectively and stiffen the world. I take away the wedges, scrub wooden mud into the crack, and apply skinny CA glue and extra wooden mud earlier than tapping the wedges again into place. This often does a first rate job of filling any deep voids and will depart the underside in a position to take a ending lower.

Mounting turned Hawaiian bowl to the lathe once it's dry
Remount the bowl to the tailstock after drying.

After the glue has dried, I mount the kū’oho in a scroll chuck and flippantly tighten the jaws (solely tight sufficient to examine whether or not the vessel is operating true). With the piece turning slowly, I see there may be a very minor warp on the rim, nevertheless it runs true on the foot so there is no such thing as a must shim or re-true the tenon. To guarantee a strong mount within the chuck, I tighten the jaws whereas urgent the tenon shoulder in opposition to the chuck jaws, utilizing a board between the bowl rim and the tailstock to use pressure.

Close-up of Hawaiian bowl mounted to lathe tailstock
Use tailstock stress to make sure the tenon shoulders seat correctly on the chuck jaws.

To end-flip the surface, I begin with the three/8″ bowl gouge. The bowl is barely out of spherical, so I run the lathe at a reasonably excessive pace and sweep shear cuts throughout the rim space to whisk off excessive spots till it’s near operating true. This is the world that’s most vulnerable to vibration from heavy bevel stress, so this lower requires a mild hand.

Using scraper to finish cuts along Hawaiian bowl exterior
A shear-scraping lower refines the bowl’s elegant traces.

I can now proceed shear-slicing additional down the bowl to the widest half. I exploit a push lower with the flute as much as true up and get a clear lower throughout the endgrain within the space from the widest half to the foot. Light shear cuts and shear-scraping handle smoothing and refining the curves. It is useful to be snug sufficient with software dealing with that you may watch the form reasonably than the software; elegant curves will make this bowl come alive, however the kind presents no refuge for clumsy execution.

I sand the surface utilizing a 5″ (13cm) disk sander and 180-grit abrasive to finalize the surface form.

Finish-turn the Inside

With the lathe operating at a medium-excessive pace, I exploit the three/8″ bowl gouge on the within of the bowl. After rigorously truing up the rim space with the gouge deal with low to current a excessive shear lower, I can begin taking down the excessive spots which might be out of spherical. I repeat this lower till I can use a comparatively shallow lower to complete truing up the wall and make a steady lower. I return to slicing with the flute dealing with up and the bevel rubbing, and make very superb cuts from the rim to the widest a part of the curve.

Aiding interior cuts on Hawaiian bowl with an armrest
The writer makes use of an armbrace software with a teardrop-formed scraper to refine the within partitions.

To end-flip the underside curve, I as soon as once more use the half of″ brief-bevel bowl gouge. I push-lower from the middle outward, by the underside and endgrain to the sidegrain transition space, finishing the curve by rolling the software into a pull lower to mix into the higher curve. I depart the very heart of the underside a little proud, so I can later sand by the restore space with out creating a divot or risking tearout. Final cleanup is finished by flippantly scraping with a teardrop scraper.

Sanding

Sander with an extension installed for deep bowl interiors
Many Hawaiian bowl types are taller than they’re huge, so a sanding pad on a lengthy extension turns out to be useful.

Many ‘umeke that I make are deep vessels with restricted entry for powersanding on the within. I’ve a number of sanding extensions that permit a deep attain and may make the most of toolrest help. One of those extensions is fitted with a 125-degree angle head and a pair of″ (5cm) inflexible backing pad. This setup may be very efficient for smoothing ripples and curves in a deep bowl. I begin with 80-grit abrasive,9 which is aggressive however does a good job 9of cleansing up any type of bruising or compressed fibers and is much less more likely to generate sufficient warmth to trigger checking within the endgrain. I then change to a softer backing pad and sand the within to 320 grit.

Final Thoughts

I mount the bowl onto a vacuum chuck to complete the underside and foot, which is a easy concave space on which the bowl will relaxation. If you don’t have a vacuum chuck, you may additionally do that utilizing a jam chuck with tailstock help.

After turning the underside and mixing the foot into the decrease curve, I can now end-sand the surface of the bowl to 320 grit.

If extra repairs are wanted within the areas affected by the pith’s cracking, I set up pewa (butterfly inlays) earlier than making use of a hand-rubbed oil end.

Pat Kramer’s part-Hawaiian heritage informs his work as a woodturner and sculptor, whose work contains each conventional Hawaiian and up to date bowls. His present focus is on the sculptural prospects of woodturning with up to date natural types. Pat displays his work in a number of galleries.



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