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Ask Dale
Ask Dale is a regular column featured in Woodturning Design. Listed below are the questions and Dale's answers from Issue 19.
I was attending a woodturning show and noticed several pieces of work which had colored stone inlaid in the cracks or knots. The pieces were quite interesting, and I would like to know more about the process.
This process has been around for a number of years and the technique is quite simple. Crushed stone and powdered stone are put into the cracks, and then saturated with thin cyanoacrylate glue (CA or superglue). The glue hardens quickly and the area is then sanded down until it is smooth and flush with the wood. The stone selected for inlay needs to be colorful and soft enough to be sanded with common power sanding tools. Crushed and powdered stone are available from several commercial sources or you can crush your own from material available at rock shops. The hardness of a stone is measured by the Moh’s scale and will range from 1 to 10. The softest (“1”) will be talc and the hardest (“10”) will be diamond. The preferred hardness range is 3 to 4, and will include minerals such as malachite (green), azurite (blue), chrysicola (blue-green), and sponge coral (red). Turquoise is harder (5 to 6) but is very popular.
Another popular choice for inlay is a synthetic product called Inlace. It is also used by woodturners for decorative filling of gaps, checks, or knots in burls or distressed wood. Inlace comes in solid colors, clear or mixed colors, or can be mixed with synthetic stones. Metal flakes can also be added to the product. This material can also be combined with real stones that have been crushed, but be sure to choose soft stones with a hardness of 3 to 6, with 3 to 4 preferable.
Once the inlay is completed and sanded down flush with the surface, sand the turning through the usual grits—100, 150, 220, and 320. Apply the desired finish, such as lacquer or a Danish oil finish.
Being a relatively new turner, it’s not surprising that I am baffled by some of the tools I see. Recently I was watching a demo at a local wood supply store and noticed that the demonstrator was using a rather odd tool. It looked like the end of a very large common nail (spike) and worked like magic on beads and the like. What is it and are there any secrets to making it work properly? Can it be used on faceplate work too?

The tool you saw being used is a pyramid point tool, historically made from a triangular file (see Diagram A). It was ground from a three-square file to a three-sided pyramid and used straight from the grinding wheel. The teeth on the file were ground back 2" or 3", and the corners rounded and smoothed on an oilstone, so it could slide easily on the tool rest. Only the three cutting edges were used. Point tools were used extensively on ivory and bone and cut par excellence. Point tools also work on not-so-hard materials, because the function is exactly the same as a skew, but with none of the common problems. The point tool is not a scraper and shouldn’t be used as one. As soon as it is tilted and one of its three cutting edges contacts the work, a shearing cut is started and a very controllable cut can be made.
The point tool has been used for years by Allan Batty and Bill Jones, professional turners from England. In recent years, point tools have been commercially manufactured from 1/4"- and 3/8"-diameter round stock, usually high-speed steel (HSS). A 1/4"-diameter point tool is a good choice with which to start, while a 3/8"-diameter point tool is good for making larger beads. Blade length is about 6" and the tool is available handled or unhandled.

Making the bead:
  • Make a pencil mark on either side of the bead position on the cylinder. Present the tool positioned with one of the triangular surfaces facing up, and make a small entry cut on each of the lines you have marked.
  • Keeping the tool horizontal, gently push it into one of the V-cuts. Roll the tool toward the center of the bead, at the same time lowering the tool handle. Stop when you reach the top or center of the bead.
  • Repeat this process on the other side of the bead.
  • It may take several cuts to achieve the shape and depth of cuts between the beads.
The point tool is designed for between-centers work, and should not be used on faceplate work.  The exception would be if you were using it to make decorative beads on the outside of a bowl.

diagram a
I know some turners use hot melt glue to attach small blanks to faceplates and such. However, I’m a bit gun-shy and a bit leery to attempt it. Are there limitations to this technique and can I use my wife’s hot melt craft glue?
Hot melt glue is popular for crafts and repairs since it sets quickly and may make less mess than other adhesives, but careless use can result in painful burns because melted glue can stick to the skin. Be sure to wear work gloves with no holes. I recommend that hot melt glues be used only for short-term solutions where little bonding strength is required, particularly shear (sideways) strength. I would not use hot melt to glue a bowl to a metal faceplate, because the heat from the headstock can transfer through the faceplate and soften the hot melt glue, causing the wood blank to come off the faceplate and possibly create a serious accident.

If it is necessary to use hot melt to glue a bowl to a faceplate, fasten a waste block to the faceplate with screws, and then make a wood-to-wood contact with the hot melt as the adhesive. Both surfaces need to be clean and dry to give a decent bond. However, there are easier, quicker, and more secure ways to accomplish this, and personally, I never use hot melt glue for this purpose.
The other turners in my woodturning club have suggested that I buy a chuck for my lathe. However, I am at a loss to decide what type I should buy—should it be a small scroll-type chuck or should I go for the larger 4-jawed one? If I buy the 4-jawed one, should I get the largest available or go for the smaller one?

Then there’s the question about jaws. There are so many different types and it’s difficult to know which ones are best. Could you provide a brief review of the different types of chucks and describe the most common sets of jaws and what they can be/are used for?
There are many different chucks on the market, but the choice depends on several factors. First, on what brand or type of lathe will the chuck be used? Second, what type of work is normally turned on the lathe? It would make no sense to recommend a heavy-duty 4-jawed scroll chuck to be used on an inexpensive, light-duty lathe with light bearings. The weight of the chuck would likely ruin the lathe in no time. Therefore, the type of lathe dictates largely what type or size of chuck is suitable.

The standard for general woodturning use are the 4-jawed scroll chucks. A number of quality chucks are in the marketplace and I will list a few of the most well-known ones in the American market. Vicmarc has a 3-1/2" or 5-1/2" diameter chuck. Vicmarc also has a new heavy-duty 6" chuck, the VL150, which can be used as a key chuck for regular jaw adjustments, or simply flip a switch to change to a scroll chuck which will allow rapid jaw opening or closing. Oneway has several models available from 3-1/2", 4", and 5-1/2" diameter. Technatool makes two chucks, a 3-1/2" and 4" diameter.

The market also has jaw choices, either serrated or smooth on the interior face. The smooth jaws will hold well and not leave marks on the spigot, while the serrated jaws will leave marks which can be turned off later. The serrated jaws have more grip on the workpiece, perhaps making the work a little more secure in the jaws, but my choice for most work is smooth jaws.

All the chucks have various types of jaws (such as pin jaws, soft jaws, long-nosed jaws, etc.) available, but initially I would purchase the basic chuck with the standard set of jaws. For example, Vicmarc has ten sets of accessory jaws available, Oneway has twelve sets available, and Nova has eight sets available, not including five different sizes of bowl jaws. This seems to be an overwhelming number, but I find the standard jaws will accomplish most of the work.

The mechanisms for tightening or loosening the jaws may be a T-handle or an operating key for one-hand adjusting of the jaws. I would recommend the small (3-1/2") chucks for work 8" to 12" in diameter, but this chuck will handle work up to 16" in diameter if accessory jaws are used. The larger chucks, such as the 5-1/2" Vicmarc, would be recommended for lathes with a 16" to 24" capacity. Keep in mind that the chuck should be used with wood that is round, well balanced, and being turned at safe and appropriate speeds. Whether used to clamp down on a spigot or expanded into a dovetail, the work must be properly prepared to fit the chuck and allow a firm grip on the wood.

In conclusion, there are some inexpensive, low-quality chucks on the market, but you usually get what you pay for. The chucks mentioned above are well made and should last a lifetime with a little care and maintenance, such as cleaning and lubricating. Carefully study woodturning tool catalogs for detailed information on each type of jaw, and purchase according to your needs.
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