The lathe is an invaluable tool as it holds the potential to make many furniture and related project parts.
1. This lathe lesson was designed to teach proper use of many lathe tools and the outside caliper.
2. It teaches how to lay out, measure, and produce an exact duplicate of a design they have drawn up.
3. It teaches the value of accurate dimensioning of turned parts so when done the parts will fit perfectly together.
Knowing these things is extremely important. Students may eventually want to make 4 identical table legs, or several matching spindle sections for a shelf unit. Both spindle (between centers) and face plate mounted projects are covered. Examples of past projects done on the lathe are shown during class to inspire and present the level of design and production students are expected to meet or exceed.
The project requirements are to design and then make a small lamp base or candle stand to assemble from a faceplate turned part and a spindle (between centers) turned part.
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| Face Plate Turning |
Templates made from chipboard (thin cardboard) that are the negative profile of the project design are a good way to transfer the design transitions to the lathe project. They are also useful to verify that what you have turned matches what you have designed. Diameters at each transition of the turning can be written on the template for reference. The cardboard from cereal and other food boxes is a good cheap source for template material. 3mm birch plywood might be used for a more durable template. If you have access to a laser cutter it can be used to cut out a very precise template. Printing out the shape on paper, or drawing it out on paper, gluing it to the chipboard, then cutting it out with scissors or a utility/x-acto knife is the low tech way to make one. Using plywood the scroll saw is the recommended tool to cut it out with.
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| Simple Spindle Project Template |
A few tricks are also demonstrated or shown, such as gluing boards together with paper (newsprint works great!) between them to make them easy to split after turning. Glue the faceplate project board to a piece of plywood with newsprint between, then screw through the metal faceplate into the plywood and not the project block. Once turned and finished it is relatively easy to split the plywood off the turned piece. All that is left is to sand off the bottom paper/glue remnants and apply some finish. Two wall mount half conical sconces shades split from one turning is one example. Half round or quarter round moldings for the edges of a table or desk project is another example. In the example below, start with paper glued between all 4 outer sections and the square core. Cap the end by screwing on a plywood disk with screws into the red area(s). Turn a cylinder. Remove (split off) the outer sections from the core. The inner red area can be removed by guiding the curves at an angle
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| Round Corner Sections From The Lathe |
Smaller curved sections can be a simpler 4 corner glue up. The inner red area can be removed with a ball end bit half exposed on the router table. The method used depends on the size of the inner cove and the sizes of available cove/ball end bits for the router table.  |
| Simpler 4-corner glue-up. |
Spindle turnings of wood projects that will eventually be split should be mounted on a faceplate on the live center end, and have a plywood plate screwed into each of the parts on both ends so they won't split apart while being turned. The turned post of a lamp base might be split so a cove can be cut down the center for the power cord before gluing them back together. You could also cut the cove on two halves before gluing them up to turn. Just plug the ends with a short dowel which can be easily drilled out after turning. You can make 4 corner table legs from one large turning using this trick. These suggestions are just a fraction of what is possible (and have been done in the past) using a lathe.
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| Spindle Turning. Grooves for live enter teeth. |
The orientation of wood grain when mounted on the lathe is also important to consider. Tall or long objects should have the wood grain running up and down the height/length. Short projects might look better with grain flat against the faceplate. You could glue up small segments to make a solid block before turning. Make segments of different color woods and then make patterns by stacking them in creative ways. A large bowl shape might be easiest to turn if glued up from 4 (or more) blocks that pinwheel together. To avoid tear out on flat grain projects it is best to bandsaw cut the project block into a rough cylinder before mounting it on the lathe. Insert a strip of dark wood into one corner of a light wood block that will be an interesting profile turned table leg. The dark corner will emphasize that interesting profile, and can be the inside or outside corner of the leg when mounted.
Blocks glued up from different species of wood can make for beautiful turned projects or parts, while giving them the skills needed and ideas when they use the lathe for furniture parts.
Why bother with faceplate mounted turnings? One example would be turning a flange for a center post to slip into under a table top. A larger flange could be the base of the same table. A whole round small pedestal/tea table top with an interesting edge profile perhaps? A large shallow dish that eventually a seat bucket for a chair may be cut from, or an entire seat pan for a stool? Turning the headstock end of the lathe around and using a free-standing tool rest allows turning large diameter table tops or wagon (spoked) wheel rims. These are furniture related faceplate mounted projects that students have created in the past.
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| A table center leg top flange |
A simple finish for lathe projects is French (Friction) Polish. A mixture of equal parts Shellac, de-natured alcohol, and boiled linseed oil can be applied to projects still on the lathe and spinning. Apply with a rag and the friction heat created is what dries the finish. Three or more coats can be applied in short time and are recommended. Keep the lid on the bottle between applying to prevent the alcohol in it from evaporating. Don't set the bottle on the lathe table where vibration may knock it to the floor. Set it on the floor where it won't be kicked if no other place is available. Lastly, don't forget the metal lathes. Metal parts for furniture have been made on the metal lathes in the past. Tapered aluminum or steel legs. Chamfers and threads cut in the ends of solid rod stretchers for tables or seating. Etc.. A top finial in brass or aluminum for the halo of a wood turned lamp might be a good project to design and make using a metal lathe. Finial Ideas Finials for the top of shelf posts or turned metal feet for the bottom are parts that have been made on the metal lathe by students in the past. As access to the metals lathes is limited, fabrication of the top finial can start with a 3D printed version. Let students use the metal lathe one after the other throughout the semester and eventually all plastic finials will be replaced by brass or aluminum versions.
A recommended assignment for this project is to have students submit a 3D rendering of their design with a dimensioned section view on the same page. Do this before they start turning wood. Skipping this step I've had students turn a random thing then measure it to make a drawing. Iterative contemplation of a design explored using the capabilities of 3D CAD software to visualize always produces better turned results than finding a shape as you turn it. Even Sketchup can be used to quickly spin a profile line around a center line into a lathe turnable 3D image to examine. The goal is to make a project that matches the design drawing in shape and dimensions.
Some related educational projects:
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