Mounting a Blank - Canadian Woodworking Magazine

Turning For Beginners 

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Mounting a Blank



There are a number of ways to mount a turning blank on a lathe. I'll show you three of the most common. The one you choose will depend on what you’re turning. I have purposely left out lathe chucks, because the instructions that come with most chucks are thorough and easy to follow.
 
Turning Between Centers
This technique is also called 'spindle turning'. Begin my marking and punching a small hole in the center of both ends of the blank. Remove the spur center from the lathe and line it up with the punch mark on one end. Use a wooden mallet or soft metal hammer (brass or copper) to drive the spur in until it is firmly seated in the blank. Extend the tailstock spindle about 1". Now mount the spur center with the blank and move the tailstock in place, lining up the tail center with the second punch mark. Lock the tailstock in place and adjust it to exert moderate pressure on the blank. Don’t force the tailstock spindle hard against the blank. Extending the tailstock spindle as little as possible will help reduce vibration. However, some situations require the tailstock center to extend more than usual. It’s good practice to check the tension on the tailstock regularly as you are turning; I check it about every couple of minutes, or any time I make an adjustment to the setup.

Using Faceplates
You can screw a faceplate directly to your blank if it is deep enough. Use the longest and thickest screws that will leave at least ¾" of material between the end of the screws and the bottom of the finished piece. Alternatively, you can use a "false faceplate", a piece of scrap wood that’s screwed to the faceplate with your blank glued to it. I keep several false faceplates on hand, and use hot melt glue for quick mounting of small pieces. It gives a fair bond but will not survive aggressive turning. Cyanoacrylate glue (instant glue) works extremely well on small to medium sized pieces. (approx. 6” diameter or less). It bonds quickly and holds well on long grain but can pose some problems on end grain. Epoxy is a good choice for larger pieces and for problem pieces, such as end grain. It also gives a very reliable bond in a fairly short period of time. The "paper method" gives a reliable bond. Apply wood glue to the false faceplate and to the bottom of the blank. Clamp the two together with a piece of paper between them and allow to dry overnight. Use standard writing paper, printer paper, or paper bag. Do not use heavier paper, like card stock, as it will separate too easily. Once turning is complete, a sharp blow to the false faceplate separates it from the finished piece. There will be some remaining residue that will need to be sanded off.


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Shop-made Faceplates
I often use a shop made faceplate when mounting turnings up to 16" diameter. It’s handy and simple to make. Start with a circular blank of dense hardwood (I use hard maple) approximately 6" diameter and 1" thick. Bore a hole in the center about ⅛" deep, the same diameter as the drive spindle on your lathe. Bore a second hole, ⅛" smaller in the center of the first hole, all the way through the blank. Place the larger hole over the spindle thread and force thread the blank on to the spindle until it’s seated (a little wax helps here). True up the edge and face of the blank and use it as you would a regular faceplate.


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In the next article I will cover the construction of a lathe steady rest, a useful jig that will come in handy as your turning skills progress.



J.P. RAPATTONI
JP Rapattoni