Woodshops: Difference between revisions
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* Wood glues (e.g. Titebond) have water in them. When you press two pieces of wood together, the glue fills the tiny wood gaps and wraps around fibers. As the water leaves the glue, the glue hardens. | * Wood glues (e.g. Titebond) have water in them. When you press two pieces of wood together, the glue fills the tiny wood gaps and wraps around fibers. As the water leaves the glue, the glue hardens. | ||
* Epoxy uses a resin and a hardener. The resin flows around the wood fibers, and the hardener links the resin together as it evaporates. Note that this process can generate a lot of heat and it must be done in a well-ventilated area. (You cannot do this at Maker Nexus.) | * Epoxy uses a resin and a hardener. The resin flows around the wood fibers, and the hardener links the resin together as it evaporates. Note that this process can generate a lot of heat and it must be done in a well-ventilated area. (You cannot do this at Maker Nexus.) | ||
* Cyanoacrylate glue (CA glue, super glue) works by | |||
* Cyanoacrylate glue (CA glue, super glue) works by flowing around fibers in the wood. As the glue interacts with ambient moisture, the glue polymerizes forming a hard substance. You have a very short amount of time to let the glue flow on the wood surface and when you press another piece of wood together it hardens and holds the opposite sides together. You can use an accelerator which is basically water in a solvent and it creates a stronger bond: the sprayed accelerator flows into the cracks of the wood and then the CA glue immediately hardens on contact. Baking soda is an accelerator for CA glue. | |||
=== Gluing endgrain === | === Gluing endgrain === | ||
Revision as of 22:13, 28 February 2025
- This page is about general woodworking tools and tips. For the wood shop at the Maker Nexus makerspace in Sunnyvale, CA, see MN Woodshop.
What is a woodshop?
A woodshop is a space for tools to process wood and soft materials. People bring in materials like plywood, solid lumber, plastics, and foam, and then they use hand and power tools to cut, assemble, and shape the tools.
Products you can make are anything from turned pens or small coasters, to boxes, to furniture and architecture:
- Blades are used to chip away at materials to cut them apart. Common tools that have blades: saws, coarse files, planers, drills, CNC routers.
- Abrasives are used to grind materials until they are smooth. Common tools that have abrasives: sandpaper, smooth files, rough paper.
- Fasteners are used to hold materials together. Permanent fasteners will deform or hook into materials. Temporary fasteners can be loosened for removal. Common fasteners: nails, screws, hooks, clamps, locks, pin nails, staples.
- Aligners are parts that keep the position of two pieces of material. Common aligners: dowels, tenons, screws, posts, biscuits, dominoes.
- Adhesives are used to bond materials together. Common adhesives: wood glue, cyanoacrylate (aka CA glue, super glue), tape.
- Finishes protect the surface and change the appearance for design or durability purposes. Common finishes: stains, paint, urethanes, hard waxes.
But what about lasers? See: Laser Cutters, MN Laser Cutters
Safety considerations
In general
- Safety is our most important priority. You cannot rush safety; woodworking just takes time. Always look at the machines and the work area. Don't distract people when they are actively cutting. Don't run or walk fast through the shop. Watch your back when turning around while holding materials. If something doesn't feel right, stop. If you need help, ask someone or a staff member.
- Do not walk away from an active cut. If a machine is running, stay with it. If you are done, turn it off, wait for it to stop moving, and then you can look away or walk away. If you need to adjust something while the machine is running, consider turning it off.
Hazards from cutting
Moving blades and rotating bits are connected to very powerful machinery, and almost all of these machines do not have a way to detect that something has gone wrong and shut themselves off. (The one exception is the SawStop.) So as an operator you must be very careful:
- No loose clothing near the blade/bit. NO GLOVES! Most of us wear short sleeve shirts and no jewelry from the elbows down. If a loose thread or a corner of your clothing gets caught then you may be pulled into the machine. Nobody likes splinters or sharp wood edges, but being mindful of rough edges reduces the chance of being poked or cut.
- You can use gloves to move materials and tools, just take them off before turning on a machine. If a machine grabs a bit of a glove, it will rip it off your hand. This is what emergency departments call a "de-gloving event." It is horrible, so do NOT wear gloves when using a machine.
- The SawStop does have a brake that will drop the table saw blade if your skin makes contact with the blade. This has saved countless people from deep cuts or worse. However, do not rely on the brake. Even if the blade drops, you will still likely get a cut or materials can get snagged and still harm you.
- Always wear eye protection. The blades and bits throw chips faster than you can react, and they are small and sharp. Choose glasses that wrap around the side of your eyes. Many of us have oversized ones that fit over reading glasses.
- Only one person on a machine. One person is usually better than two. Woodworking involves subtle movements to move materials around and machines are very loud.
Hazards from dust
- Consider wearing a mask or respirator. Sawdust stays airborne for a long time and it is an irritant. Prolonged exposure to sawdust can create serious health concerns. An N95 or N100 mask is great to keep the particles out. Many of us use masks with replaceable filters because they are more comfortable to wear and have a better seal.
- Use dust collection. Whenever possible, use the dust collectors attached to the machines or a ShopVac. A downdraft table also helps to capture particles. After you are done with a machine or sanding on a table, use broom to push dust into pans and place in garbage cans.
- Clean around the machines. Dust is also slippery. The floors should be relatively dust-free to prevent slipping when walking or turning.
Hazards from fumes
- Do not cut materials that could give off fumes. When in doubt, ask a staff member and try to ventilate the shop. Some materials with paints or plastics can heat up and release hazardous gasses, so be mindful of what you cut. That said, everything gives off some amount of fumes such as cutting MDF, using glue, or applying finishes.
Hazards from nails and screws
- Do not leave sharp fasteners on the floor or tables. It's easy to step on or grab a nail or end of a wood screw. Put the fasteners back in their bins or bags, or sweep them into garbage cans.
Hazards from falling materials
- Use support arms or support stands. You only have two hands and when you cut materials the two halves often pivot away in opposite directions. In the case of a miter saw this means the cut ends of the materials can fall away and pinch the blade: this will throw the wood back at you. Extend support arms or use a stand.
Hazards from kickback
- Wood pinching on a spinning blade can throw wood back at you or someone else. It happens faster than you can react. Always keep pressure and control on your material and watch for any opportunity to have the wood pinch the blade or turn oddly into the blade. Even if you push wood through the table saw cleanly, the wood may relax beyond the blade and curve inward. Always know how to stop the machine or keep control of the material.
- Use the Riving Knife. This is a key safety device to avoid kickback. You should never use the table saw without the riving knife in place.
- Don't stand in the path of small thin material. When cutting on the table saw you may be ripping a small strip off one side. Stay to the left of the saw blade and allow a small gap so that if kickback happens then the small piece will shoot past your hip.
- Use a miter gauge or crosscut sled for material that is wider than it is long. A miter gauge or sled rides in a track that prevents the material from turning left/right. Holding your material to the miter gauge or sled lets you safely push it through a table saw blade.
- Clamp non-square material. Anything at an angle should be clamped to a sled or a miter gauge. This goes for round poles. And this is for the table saw, miter saw, and band saw. The blade will grab a round side and spin it harder than you can hold onto it.
- See also: Table saw accidents
Materials
Wood
Of course, wood! Check out the Wood Database for tons of information about different woods. Identification, strength, finishes, etc.
Solid wood
These are going to be your general lumber. Basically a tree that's cut into boards that you can reduce to the sizes you need.
Lumber yards are your best bet for quality and selection, but a local hardware store will stock some things you can use.
People love the feel of "real wood" and it has advantages like being shaped and sanded. You can think of it as a solid material---it's really more like a bundle of straws stuck together with natural glues. However, wood will expand sideways because the wood cells are great at holding moisture. (It was a tree, after all.)
Engineered lumber
These are mostly your plywoods and sheet materials. Most are trees that have been peeled into thin layers, then assembled into panels with glue. Plywood usually has grain placed at 90-degree angles on every other layer, which gives it strength and also means it doesn't change shape that much with weather. There are many types of plywood: cheaply-made big layers that have voids ("holes") and knots, better quality that have less voids or that use MDF cores, or higher end which have smooth void-free sheets and clean veneers.
There are boards made from long flat wood chips: oriented strand board (OSB). It's like plywood, but more glue and less strong. It's better as siding panels.
And there is medium density fiberboard (MDF). This is basically sawdust with glue. It's perfect for making templates or creating complex shapes. It is very heavy (because it's mostly glue) and weak when bending.
Bamboo panels are a little like MDF: bamboo is oriented with ends out and glue fills the gaps. It is very heavy, easy to shape like MDF, and looks nice on the sides and top.
Glues
Most popular glues come from processed oil and they form an incredibly strong bond with wood fibers. Here is a good [explanation video].
- Wood glues (e.g. Titebond) have water in them. When you press two pieces of wood together, the glue fills the tiny wood gaps and wraps around fibers. As the water leaves the glue, the glue hardens.
- Epoxy uses a resin and a hardener. The resin flows around the wood fibers, and the hardener links the resin together as it evaporates. Note that this process can generate a lot of heat and it must be done in a well-ventilated area. (You cannot do this at Maker Nexus.)
- Cyanoacrylate glue (CA glue, super glue) works by flowing around fibers in the wood. As the glue interacts with ambient moisture, the glue polymerizes forming a hard substance. You have a very short amount of time to let the glue flow on the wood surface and when you press another piece of wood together it hardens and holds the opposite sides together. You can use an accelerator which is basically water in a solvent and it creates a stronger bond: the sprayed accelerator flows into the cracks of the wood and then the CA glue immediately hardens on contact. Baking soda is an accelerator for CA glue.
Gluing endgrain
Remember that solid wood ends are like the edges of a bundle of straws: the surface is actually very uneven and those open ends want to soak up glue (or finish!).
Putting glue on the end grain is said to create a weak joint because the glue doesn't have a lot of sheer strength. But, this video shows how strong the glue itself is:See the short, very interesting test video.
Some local knowledge from our members.
Finishes
- Odie's Oil
- Wipe on, dry, wipe off. 2 coats usually good. Generally easy to apply.
- For larger endgrain slabs, recommendation is to use thin coat and allow 1-2 days per coat to dry completely.
- Cookie slabs can retain a lot of moisture and that will interfere with the hardening process.
- Tung oil finishes
Supplies
Also see the general Supply Sources page.
Tools
Bench Vise
- How to pick a vise? A fun video with serious information
Wood Lathe
- Using a skew. Nice video explaining skew angles and when to use each.
Wood Chisels
- Sharpening: The grind on DeWalt chisels is very rough out of the box. The edge isn't durable because it is very jagged. To get a good edge on them you need to carefully flatten the surface of the bevel of the chisel with a rough sharpening stone before moving on to finer grits. Sandpaper is not the right tool for the job.
Tips
Basic Tips
Wood Inlay
- How to create dramatic inlays with epoxy
- $15,000 Kitchen Island. Good tips on the overall process of a wood countertop, including epoxy inlay.
Edge Treatment
- Making Edge-Grain Patterned Plywood. The link drops you to the finished piece, the whole video shows how he did it.
Sanding
- So, you think you know how to sand, eh?. Learn to sand correctly.
- Drum sander tips
Table Saw
- General intro to table saw safety
- Blade Height - what is the right height for your cut?
- Tablesaw set up - excellent tips on safety that you might not know about.
- Kickback and how to avoid it. Work safely!
- A different kind of kickback!
- Three different blades - why to use each
- Jointer, Planer, Drum sander - what do they each do and why?
- Half laps on the tablesaw without a dado set
Router
Drilling
- Forstner bits and how to use them
Turning
Misc
- An analysis of Parallel clamps
- Tips on precision work with our tools
