Material:Wood

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Wood

Stack of wood.JPG
Synonyms: timber (unprocessed), lumber (boards etc.);
DE: Holz, Massivholz
On Site? a few scraps of varying kinds & sizes
Location: wood workshop
Suggested Tools: saws, router, wood drill bits, laser cutter,
CNC router, pyrography burner, planes,
rasps, files, sanders, sandpaper, ...
Contains: mainly cellulose and lignin
Similar (More or Less): engineered woods

Much like "plastic" and "metal", "wood" is a pretty broad term encompassing numerous different materials. Although they share many characteristics and can generally be shaped with the same tools, features like stability, grain and surface finish vary greatly between different kinds of wood.

Besides natural woods from different tree species that this page focuses on, there are engineered woods (DE: Holzwerkstoffe) with artificially enhanced advantages. Veneers can give such engineered woods the surface look of massive wood at first glance, and cut faces can be made more attractive by gluing on edge banding.

We usually have some scraps and reclaimed wood in store but you should expect to have to bring your own if you need large amounts or a specific variety.

Structure

Wood is an anisotropic material, i.e. its structure changes throughout a piece and with different directions. The reason for that is the grain (DE: Maserung), caused by the (more or less) parallel orientation of fibers in a growing tree.

There are also changes in density with growth rings (in non-tropical wood - denser wood being produced late in the year) and very dense knots where a branch used to sit.

"Reading" wood grain is an important skill to practice in the wood workshop, whether simply recognizing end grain that is bad for gluing and screwing or [analyzing the less obvious orientation of side grain for cutting operations.

Varieties

The list of woody plant species goes on for a while - here we collect some that have been used for woodworking in our community.

Wood is often separated into softwoods and hardwoods.

Hardwoods

Wood from broad-leaved trees (DE: Laubbäume) - harder due to (more or less) slower growth, therefore also more expensive than softwoods. Fast-growing trees like willows, poplars or birches produce much softer "hardwood" than others.

Softwoods

Wood from coniferous trees (DE: Nadelbäume) - fast growth, therefore commonly available at low prices with the downside of reduced strength and a much coarser grain. Again, not all softwoods are equally soft!

  • spruce (DE: Fichte) or fir (DE: Tanne) - often undistinguished and labeled "FI/TA" at the store
    • common construction beams

Marking

Pencils work great on wood, often used together with a square to obtain right angles. Most woods are also easily scratched by a pricking awl.

Shaping

The most common cutting tools for wood are handheld or powered saws. Using a router or woodworking chisels expands your threedimensional options.

We are also working on establishing CNC techniques such as CNC routing and laser cutting.

Sawing

As wood is fibrous, ripping it apart with the teeth of a blade can cause unsightly tearout/chipout/Ausriss. The splinters will always occur on the side where your blade exits the workpiece. There are a few precautions you can take against this effect though:

  • zero clearance boards
    • e.g. as insert on a table saw or little plastic square on a jigsaw
    • leave no room for the wood to "escape" the blade
  • adhesive tape along the cut line
    • please let us know which ones work well!
  • working from the proper side of your workpiece in case the other one won't be seen anyway

Holes and Recesses

Use wood drill bits for round holes and recesses (Vertiefungen) and a router or chisels for custom shapes, e.g. mortises.

With hole saws or a jigsaw you can cut holes, but not recesses.

Chamfering

"Breaking" sharp edges by cutting a chamfer (Fase) can have a great aesthetic effect and may improve your product's handling.

Common tools for chamfering (Anfasen) include planes, rasps or files, chisels and coarse sandpaper. A router with an appropriate bit or a bow sander help you achieve edges that are rounded over.

Steam Bending

Wood can be forced into a curved shape under exposure to heat and moisture (steam!), but this is something we do not have experimented with so far. Especially beech and birch are suitable for bending. [1]

Bent Lamination

Thin strips of wood are pretty flexible along their grain direction and can be brought into many interesting shapes like spirals or the belly of a boat if you glue them together in the desired position - you'll basically end up with custom plywood!

Gluing

Wood is commonly glued with wood glue but other adhesives may be needed when trying to glue other materials to wood.

Finishing

Sanding

Common grit sizes for sanding wood are 80, 120, 150 and 220. Check out this sanding basics video tutorial.

You may want to consider raising the grain before the last sanding pass if you are going to apply a water-based stain in the end.

Polishing

Very fine sandpaper grits and special polishing pads can make wood extremely smooth.

Planing

Some woodworkers don't use sandpaper at all but produce silky smooth surfaces with nothing but hand planes!

Oiling/Waxing

To preserve or refresh the shine of a polished piece of wood, oil or wax can be rubbed into the surface. We do not have a lot of experience with these finishes yet.

Burning

You can try adding dark accents to your workpiece with a pyrography burner, laser cutter, hot air or even open flames! Do leave some actual wood behind, not just charcoal ;-)

Intense burning can also be used to shape wood or seal its surface against harmful environment conditions.

Sourcing

Wood

Paint and Chemicals for Wood

  • hardware stores (see above)
  • Baufix in HD-Rohrbach Süd

Further Reading

  • The Wood Database with information on pretty much every species you can imagine
    • e.g. hardness, shrinkage, identification, project suitability
  • DE: Holzarten-ABC vom Fachverband deutscher Holzhändler
    • Materialkunde so gut wie aller Holzarten, mit Verarbeitungshinweisen, Austauschhölzern u. v. m.