RIKON Power Tools 70-300 - Manual (Page 15)

15
Checks & Cracks
Green wood will check and crack. For best results, leave logs in as long lengths as you can handle.
As the material starts to dry, surface cracks will develop on the ends of the log. Cut off two to three
inches and you should find good, sound wood. Also cut the log in half along the pith to avoid having
it in the finished piece. Most checks radiate from the pith. As you turn bowls from green wood, make
sure you maintain a consistent wall thickness throughout the piece. Leaving a piece thick in some
areas and thin in others will cause the wood to dry unevenly and promote checks and cracks.
Distortion
Distortion is a problem associated with turning green wood. It will vary from one type of wood to the
next. Typically, fruitwoods tend to distort more than others. It also varies with the time of year the tree
was cut and how the logs are stored.
Tools for Bowl Turning
The deep fluted bowl gouge is the most essential and versatile tool for most bowl and faceplate style
turning. The bowl gouge is heavier and easier to control than other types of gouges. It also allows
removal of wood much faster and with less vibration than other gouges. Most average sized bowl
work can be accomplished with a 3/8" or 1/2" bowl gouge. A 1/4" bowl gouge is best suited for smaller
bowls and light finishing cuts.
Larger 3/4" and 1" bowl gouges are only used for extremely large pieces. Large domed scrapers can
also be used to help clean up the interior surfaces of bowls. A light touch with the scraper slightly
tilted will eliminate some of the ridges left by a bowl gouge.
To Shape Outside of Bowl
1. Odd shaped burls, crotches and other irregular shaped blanks require special preparation before
mounting in a chuck, or onto a faceplate. Remove the bark, if there is any, from what appears to be
the center of the top of workpiece.
2. Drive spur center into the top of workpiece with a wood mallet.
3. Slip spur center into headstock taper and bring the tailstock, with a live center into position. Lock
tailstock to bed and advance spindle in order to seat the cup center into workpiece, see Figure 19.
Tighten quill lock.
4. Position tool support just below the centerline and about 1/4" from the workpiece. Note: For larger
outboard turning, an optional outboard turning stand is used to place the tool support.
5. Turn workpiece by hand to ensure proper clearance.
6. Start lathe at lowest speed and bring it up to the maximum safe speed for the size of work to be
turned, see Figure 7 on page 10. If the machine starts to vibrate, lower the speed until vibration stops.
7. Rough out the outside of the bowl with the 1/2" deep fluted bowl gouge, holding the tool firmly
against your hip. For best control, use your whole body to move the gouge through the workpiece.
8. As the bowl takes shape, work on the bottom (tailstock end) to accommodate attaching a face