The majority of residential furniture is made from wood. Most places there are usually many local or regional hardwoods to choose from with aesthetic and structural property variety. While you can find wood properties on the web or in books, being able to handle and machine and sand and finish and weigh several is by far the best way to learn about them. Knowing the unique properties of several is critical when choosing which one(s) to use for your furniture or other wood projects.
Making a set of sample blocks is a good way to learn those unique properties. You end up with a useful reference set to look back on and also show potential future clients.
The samples here are 5 inches wide, 8 inches long, and minimally 3/4" nominal thick. Approximately .28 bd. ft. each. Thicker boards present more surface area on the sides and end, so choose 6/4 or 8/4 wood if you can. Nothing critical about these dimensions except it is easy to find hardwood boards that are 5" wide or greater. Make them from whatever hardwood species are available locally/regionally. The top face has a 1/8" wide and 1/8" deep groove down the middle in both directions to create a separation between the 4 corner sections. Continue the groove down the sides and ends. The groove also comes in handy when finishing each corner as you can stick a cardboard shield in them to protect the neighboring corners from brush or overspray. A small bevel or small roundover cut on the sides will ease the square edges and make a smooth transition from top to side and end surfaces.
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| Unfinished 4/4 Block |
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| 8/4 Nominal Block |
Now you have four corners that each can have a unique finish applied. It is invaluable to see the difference in how end grain and side grain can look with each finish. The quarter sawn grain view of red or white oak or white ash is considerably different than the face grain. Flecks and medullary rays add visual interest, and the parallel growth ring lines can reinforce and contribute to the visual aesthetics of a rectilinear design. Many hardwoods have similar aesthetic difference between their face grain and quarter sawn grain. In fact for the woods listed above a sample block composed of 1/2 face grain and 1/2 quarter sawn wood glued side by side helps see and appreciate the difference between the two views of the wood grain.
The back face of the blocks is a great place for labels to record the stains and finishes used on each respective corner. Typically 3 corners have a stain or dye or bleaching treatment on them with a clear topcoat. The 4th corner is left natural with only a clear finish applied. Sand all blocks progressively up to 360 or 400 grit, making sure to remove all tool marks. Follow with 0000 Steel wool. A good visual test is to see if you can see reflections of overhead lights with no obvious scratches in the sanded surface.
Once ready for finish it is worth having a postal or kitchen scale in the shop so each block can be weighed. Record the weight on the back of each block. Why? Weight is a property of wood. Wood weight varies considerably between species and can vary a little between different trees of the same species. How dry the wood is also affects its weight. Despite that knowing the relative weight of each available wood species comes in handy when choosing the wood to use for a project. Making a portable table or desk? Choose one of the lighter weight woods. The identically sized blocks make for easy weight comparison. Knowing the weight and volume of a sample block you can extrapolate to calculate the expected final weight of a project design. I've known many students who simplified/scaled down their designs or at least changed which wood they planned to use once they calculated approximately how much their proposed design would weigh.
Making the blocks also presents an opportunity to learn the table saw, and a crosscut saw, as well as one or two ways to make the grooves (router table and a 1/8" end mill, or table saw set 1/8" high), and chamfering or rounding over edges. Throw in learning about sanding and sandpaper grits. As all blocks are the same length this is a good time to demonstrate using a stop block clamped to the compound miter saw or radial arm saw fence. When every student has a set of blocks that are the same dimensions it speeds up getting the centered slots cut. Once a tool is set up for a cut all students can use it. The sanding and finish application of these blocks can happen over time. It is a good project for students to work on when they are waiting on supplies or machine availability for their other projects.
In addition to hardwoods, a block made from 18mm Baltic Birch plywood with veneer applied makes a nice addition to the reference set. Students get to know about veneers and how to apply and trim them flush. Some edge trim can also be added on the long sides so students can learn how to apply it, and see the difference between a veneered edge verses a smooth sanded plywood edge. Perhaps apply a 1/8" thick piece of matching hardwood trim to one long side, with edge veneer to the other.
Other materials might be used to make furniture or furniture parts. Steel, Aluminum, and Acrylic samples are opportunities to learn how to clean and sand and finish the metals, and polish the cut edges of the acrylic piece to where you can see as easily through the edges as you can through the face. Add a lesson on acrylics with a demonstration on how to bend it, polish the edges, and solvent weld pieces together. Some students may choose to peen a texture into the steel. Prime and paint or powder coat the steel after cleaning it. The Aluminum can be sanded then polished to a mirror finish, then coated with wax to keep it that way. These samples can be 2" x 5" x 1/4" thick. Cut from 2" wide flat stock. Think of one more and a set of 4 will fit in the same area as the 5" x 8" wood blocks.
These samples are themselves an end project. A step they'll need and appreciate they have when it comes time to choose and finish materials for their more complex projects. More blocks could be test samples for other techniques the students might want to use on future projects. V-Carve inlaying of contrasting wood into a board is one. Resin fill of carved patterns is another. Laser etching on wood, carved texture variations, and 3D surface creation are just a few of the possible opportunities for useful samples to add to the set.
Other educational projects:
Making Projects vs Making Samples.
Tool Names and Their Functions.
Calculating actual project costs.
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