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PROCEDURE Before using the lathe, I make the hole for the candle about 1" deep. It is the only part of the object that is not turned and I want it to look as finished as the rest of the piece. I use a slot mortiser with a router bit; the result is cleaner than the cut from a drill bit. The hole is not parallel to the edge of the wood, but angled and aimed at the center of the wood at the bottom. This is easy to accomplish on a mortiser simply by angling the block of wood before clamping it down. To achieve the correct angle on a drillpress, I would draw the line of the axis on the side of the candlestick blank and shim the blank until that line was vertical (2). If it is not drilled at the correct angle, the candle will end up tilted (3). Next I turn a small piece to act as a plug for the hole. It needs to be at least 1-1/2" long so that it can be removed when the turning is completed. It is also important that the plug is a true cylinder and that it slides all the way to the bottom of the hole without any slop, because I want to clamp the plug against the bottom of the hole. I once made a plug that was more of a wedge. Initially it worked fine, but as the top of the candlestick got reduced down to its final dimension and the piece was just about done, the plug caused the wood to split. Not convinced that that was the problem, I did it again with the same result. Sometimes you only have to make a mistake once to learn a lesson, but sometimes repeating it several times helps to convince you to do things differently. In turning, I’ve found that when pain is involved, I try to learn my lesson the first time, but everyone is different, so pick what works best for you. I don’t use any special chucks or fixtures for any of the work that I do, and this project is no different. Using a safe center (cup center) in the drive end, as opposed to a spur center, is a very safety-conscious plan, one that I live by for all between-center turning. In the tailstock I also use a live center that ends with a cup center. The best supplier for both of these is Oneway Manufacturing. Robust Tools has come out with the most accommodating toolrests to date. They allow you to have your hand fully under the tool and to use your index finger as a guide, a need that has gone unaddressed for many years. Although they designed it for their own lathes (which I haven’t tried), it is an excellent after-market item for any lathe. In my article on “The Rolling Pin” [Woodwork #55, August 2007], there is detailed information about centers and tools that I use for spindle turning. One of the biggest differences between multi-axis turning and straight turning is that a lot of multi-axis turning requires an interrupted cut, when the tool is only in contact with wood for part of each rotation. The best way to deal with that is to understand where the pressure on the tool needs to be applied. It is not by forcing the tool against the wood or by riding the bevel. You should exert pressure down on the tool onto the toolrest rather than onto the wood (4), and touch the bevel rather than ride it. It’s a problematic cycle: pushing the tool against the wood will result in a very uneven cut because the wood will constantly be pushing the tool back toward you and you will be countering by pushing the tool toward the wood. This effect would continue until the wood was round, but since some parts of off-center turning will never be round, proper technique is essential. Vibration is an additional factor. Turning a piece that is out of balance usually requires slowing the lathe speed. The proper speed depends on how out-of-balance the wood is, whether the lathe is bolted securely to the floor, and how substantial the lathe is in the first place. A variable speed lathe is really useful because it allows you to turn the wood as fast as possible without vibration. Additionally, tool vibration occurs because the toolrest has to be further away from the work than is usually desirable. A detail gouge will tend to vibrate if it is extended 1-1/2" beyond the toolrest, causing a chattered cut, which, while interesting, may not be what you’re looking for. The tool that I use primarily for turning this candlestick is the 5/8" bowl gouge, ground to a 30° angle (5). I do the final clean up of the entire form with a 1/2" detail gouge. When the form is close to the final shape, I angle the toolrest to allow very little tool extension, thereby avoiding vibration. | |||||||
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