Building furniture or shelving generally requires some specialised tools, and joinery or welding skills. However if you like an industrial look to your furniture, you can construct simple pieces using pre-threaded pipes and fittings.
You can find threaded pipe in varying diameters and lengths at your local hardware store, along with many common fittings such as elbows, tees and flanges. You don't need any special tools or skills to put them together (just, you know, hands to thread the fittings on to the pipes) but you may need a bit of planning to create a sturdy piece.
You can add wood into the mix to make shelving, table tops, and pretty much anything else you can think of.
Things do get a little tricky when trying to create complex shapes. For threaded pipes you can use a union like this to get you out of most tough spots when trying to create a "closed" shape. You can also use non-threaded pipes and Kee Klamps for simpler assembly. Some stores will cut pipes to a custom size and thread them for you as well.
While I haven't found this method of building to be cheaper than using just wood, it is an easy way to build many different types of furniture (and the pipes can always be reassembled as something else in the future.) Here are a few examples of wood-and-pipe projects.
I used gas pipes to create the shelving units in the wardrobe of my last house. While the industrial look definitely fits my aesthetic, I also liked that the shelves were much sturdier than the builder-grade wire shelving units you often see in a wardrobe, but still provided openness between the shelves, instead of a built-in wood unit that would have made the room seem smaller. You can see more pictures and specifics on building shelving with threaded pipe here.
This bench by HomeMade Modern uses pipe pieces in a more modern way than simply attaching pipes and flanges as straight legs. The video shows a bit more about the assembly of the piece, along with how pipe clamps can be used to secure the wood to the pipes.
This dining table required a little work to assemble the boards for the top of the table, but the base was relatively simple. You can learn more about how this table was made here.
There are an infinite number of ways you can configure furniture, storage, and decorative pieces using wood and pipe, and while the look might not be for everyone, it's a fairly simple way to create quick, sturdy furniture.
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