Article: Glenn Lucas Demonstrates For CMW September 27, 2014
October 07, 2014 10:49, submitted by Tina Collison (author: Bob Gunther)
Glenn Lucas Demonstrates for CMW September 27, 2014
Glenn grew up on a farm in the foothills of Mount Leinster, CO Carlow, Ireland. He developed a love of working with wood at an early age. At 16 he became passionate about woodturning. He realized quickly that there was a demand for his well designed and handcrafted pieces.
When Glenn finished school in 1993 he began an apprenticeship as a cabinet maker (Carlow, Dublin, Germany) where he learned many new skills. In 1996 Glenn set up his own business as a woodturner and undertook a 2 year business course with the Crafts Council of Ireland in Kilkenny and Carlingford CO, Louth. Since then the demand for his work has grown steadily.
Glenn returned with his family to CO Carlow, Ireland in 2005 where he built his home and studio. From there he runs a business that produces approximately 1,500 fine crafted bowls annually. In addition, Glenn frequently receives invitations to participate in national and international exhibitions promoting the best of Irish craftsmanship.
Glenn makes all of his salad bowls from locally sourced native hardwoods, especially beech. Each piece is dried slowly in a kiln to ensure that it is suitable for use in the home. This process takes up to eight weeks. It is skillfully hand-turned to produce the purest of forms and finished with natural oils to protect the wood and maintain the richness of the grain. Lovers of craftsmanship and food around the world enjoy and treasure Glenn's pieces. He last demonstrated and taught a class for CMW in 2011.
Glenn began his demo with a slide presentation depicting details of his shop and the obtaining of wood for turning. Due to winter storms in his area of Ireland there has been an abundance of wood. Local tree men know what Glenn wants and they earmark those pieces for him. Most of what is harvested is Beech and Ash. Cutting and preparing blanks was shown. Glenn sprays silicone on his band saw table and the blade to prevent gum buildup from the wet wood. He uses a faceplate that has 3 pointed prongs and not faceplate screws. The prongs are compressed into the blanks by bringing the tailstock up. A Oneway coring system is used to decrease wasted wood and increase production. His rough turned blanks are placed in his kilns for about 8 weeks. Before drying end seal is used. He does not use Anchor seal. He uses a glue/water preparation. When turning, Glenn wears a 3M Versa Flow respirator. Finishing is done with Danish oil or Walnut oil. For shipping the bowls are wrapped in butcher paper and not in bubble wrap. His salad bowls are open in design. This shape permits efficiency in wood use and rapid production.
Glenn began the turning portion of his demo turning a 12 inch dinner plate using 8/4 cherry. The thickness of the blank was reduced on the lathe to about 6/4 inches. The piece had been kiln dried. His plate and platter blanks are gotten from the center slabs of a log on either side of the pith or above or below it. Selection of blanks from these areas prevents or minimizes warping during the drying process. Glenn uses 3 grinds for most of his bowl turning. All are done with the Oneway Vari-grind jig. They are color coded. Red is used for rough shaping of wet or dry bowls and for refining the shape. This grind has a 55 degree bevel and swept back sides the length of the tool's diameter which is 5/8 inch. Green is a ½ inch bar bowl gouge that is used for refining the shape and for finishing cuts. The bevel is 45 degrees. Again, the swept back sides are as long as the diameter. The third grind is the blue coded one. It has a bevel that can be 55-65 degrees. It is a 5/8 inch bar stock and is a bottom bowl gouge. It is used for finishing cuts on the interior bottom of the bowl.
Glenn began turning the plate from the headstock side and rounded off the edge. The piece was mounted on a 6 inch Oneway faceplate. He then cleaned up the edge of the piece. A red line was drawn down the center of the bowl gouge flute. This is used as a guide and safety aid when turning. When cutting the tool is rotated so that the red line cannot be seen. This prevents catches. Wood was then removed from the flat tailstock side of the piece which will be the base of the platter. This was removed in increments and then the entire surface was smoothed. When making a plate the base is about 70 percent of the outside diameter.
The outer shape of the plate bottom was formed. An ogee design was used. A push cut was used to refine the surface. To maintain the same continuous ogee shape the depth of the finishing cut needs to be constant. The edge of the rim was then rounded. The center of the bottom was then turned. It should be either flat or slightly concave. Then a recess for the chuck was made. Calipers were used to scribe the recessed area. Only ONE leg of the calipers is held against the wood - not both. A square end scraper was used to cut the recess beginning at the smaller diameter and moving outward to the final diameter. Glenn uses dovetail jaws so that the recess is slightly undercut. This is done with a skew. The undercut is important because its angle must very closely match the angle of the jaws. A small decorative bead was then made around the recess using the skew. Glenn would then sand the bottom and coat it with Mahoney Walnut Oil. His sanding is done with the oil on the sandpaper at a low lathe speed.
The piece was removed from the headstock and the faceplate removed. The chuck with the dovetail jaws was placed on the spindle and the piece was placed in the jaws. The face surface of the piece was leveled starting at the center. Hollowing was begun at the center and worked outward. Each cut was started with the flute at right angles to the wood. This prevents the tool from skating across the wood surface. If the flute is angled to the left it will skate to the left. If it is angled to the right, it will skate to the right. Before hollowing too much away the rim area is turned. This keeps the piece stable and helps prevent vibrations. A small bead was then made around the rim with a skew. A V-cut is made and then the bead is formed.
The interior of the plate was then hollowed beginning at the center. Wall thickness was measured using calipers. Glenn wants the bottom to be about ¼ inch thick. To get a finishing cut across the bottom he used a 45 degree bevel gouge (green). An alternative to achieve this surface finish is to use a round nosed negative rake scraper (1 3/8 inch x 3/8 inch / 33 degree bevel). The burr on the scraper has to be on the upside of the scraper. This completed the morning session.
The afternoon topic was to make a salad bowl using wet wood. The blank was a 4 inch thick, 12 inch diameter piece of Sycamore. When Glenn gets a log he cuts the first 4-5 inches off. This goes in the firewood pile! He does not use wood that has cracks or checks. The blank was placed on a faceplate and then on the headstock spindle. When Glenn places the faceplate on the spindle, it is not locked. This prevents damage to the spindle threads. A tailstock cup center was used for support. Glenn began by taking off the corners of the blank. A line was scribed in the center of the edge of the piece. Another line was scribed 2 inches in from the outside diameter. A third line was scribed showing the diameter of the base. The area between the edge line and the line two inches in from the edge was turned away. The tenon diameter was then drawn. All the bowl turning cuts are from the base to the top (like sharpening a pencil). The tenon was then formed and the outside of the bowl competed. The shape of the tenon to fit the dovetail jaws was made with a specifically ground cutter to the proper angle.
At this point the blank would be cored out but this was not done in the demo. Glenn showed some finishing cuts that would be done on a dry piece. A push cut was done that would be used to round a dry blank. The red gouge was used as described earlier. Then the green gouge with the 45 degree bevel was used to get a finished cut. Cuts were made from the base to the rim. There are three levels of cuts that produce three levels of surface quality. The push cut (best), the shear cut and the shear scrape.
The piece was removed from the faceplate, reversed and placed on the chuck so that hollowing could be done. The center of the tool rest was set at the edge of the bowl. The face was leveled off and the sharp edge removed. The red gouge was used to begin hollowing from the center outward in increments. Then deeper cuts were made. If one wants to keep the piece secure in the chuck, all the cuts should be done with the tool tip pointed at the chuck. When working deeper into the bowl, lighter cuts should be taken because more and more end grain is being dealt with as one gets to the bottom areas. Wall thickness was checked.
Glenn keeps the upper wall thickness a little over 1 inch/10 inch bowl and in the lower, base areas less than 1 inch - about 3/4 inch. To get to the deep portions of the bowl the tool rest should be moved so that it enters the bowl from the opposite side of the interior of the piece. This lets the gouge do its job with much less extending off the tool rest and thus less vibration. The gouge handle moves in a 90 degree arch when cutting the interior from the rim to the bottom.
At this point Glenn pretended that the bowl was dry and needed to be finished. First the rim was turned using the green gouge (45 degree bevel). The sharp corners were removed. Then the interior surface was finished down to near the bottom. To do the deeper areas the blue gouge (55 degree bevel) was used. This has shorted side wings.
Next, Glenn turned to sanding with the piece dry. He uses a power sander with a speed of 2800 rpms. He buys 6 inch discs and cuts them with a punch (i.e. leather punch) into 2 inch and 3 inch discs - 2 of each from each 6 inch disc. Lathe speed is set at about 500 rpm. When sanding Glenn does not look at the sanding pad but watches the dust leave the wood surface on the upper surface of the bowl as it turns. Outside surfaces are sanded with 150-180-220 and 320 grit pads. On the interior the lathe is stopped and the two areas of end grain are first sanded and then the entire surface with the lathe turning. Less sanding is needed in the deeper areas.
For finishing Glenn uses 2 finishes - Danish oil or Mineral oil. He does not use wax on a bowl. When he uses Danish oil he uses three coats. He applies the oil by hand in a circular motion then immediately wipes it off and lets the piece dry overnight. The next day the bowl is lightly sanded with fine paper with the lathe in reverse then the oil application is repeated as above. The third day it is again sanded and the oil repeated which completes the finish process.
To turn the base a jam chuck is used and then a vacuum chuck for the final finish at the bottom. If using an oil finish one needs to be aware that it is possible to get a ring formation in the interior of the vessel if a vacuum system is used.
This completed a fast paced, interesting and enjoyable demonstration. A DVD will be available in the club library in December 2014.
Submitted by Bob Gunther