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Transcript of butt joint
Carpentry and masonry
Carpentry and masonry
The butt joint is the most basic and simple joint.
Made with only two pieces of timber that are butted together at the ends.
The weakest joint that is used in woodwork but it is also the easiest to make.
It is only used in basic woodwork projects.
How to Make Butt Joints
Step1: The butt joint is very simple to make and you start by measuring out the lengths you want your timber to be and then using a try square mark a straight line across the timber where you are going to cut it.
Step2: Now cut your timber at the line you have marked and repeat steps 1 and 2 on your next piece of timber
You can either use a hand saw such as a tenon saw to cut your timber or you can use a drop saw. If you are securing the joint together with pieces of dowel drill the holes accurately now before you begin step 4.
Step3: Secure your first piece of timber in a vice or to the side of a bench with clamps but keep the top flush with the rest of the bench.
Step4: Apply some glue to the top of the secured timber and then place your next piece of timber directly over your first piece making sure to line up the edges. Now clamp up the joint or hammer in some nails or add some screws.
Step5: Now check to see if you're joint is square and leave it to dry. If you are putting nails or screws in the joint check it is square before you use them. Step6 Optional: You can strengthen your butt joint by securing a square or triangular block of wood to the inside of the joint which also helps to prevent movement.
tenon sawdrop saw
IMAGES OF BUTT JOINTS
Most simple joint
Can be strengthen relatively easily
Weak due to small gluing area
Reinforcing Butt Joints
Dowel reinforced butt jointHoles are often drilled with the assistance of a dowelling jig which aids in accurate hole placement accuracy is paramount in this technique to ensure members line up perfectly in the completed joint. The holes are drilled such that there are corresponding holes in each member into which short dowels are inserted with some glue. The joint is brought together and clamped until the glue has dried.
The biscuit is an oval shaped piece of specially dried and compressed wood, usually beech, which is installed in matching mortises in both members of the joint in a similar fashion to a loose or floating tenon.
A biscuit reinforced butt joint
The screwed butt joint uses one or more screws inserted after the joint has been brought together. The screws are usually inserted into an edge on the long grain side of one member and extend through the joint into the end grain of the adjacent member. For this reason, long screws are required (usually 3 times the thickness of the member) to ensure good traction. These joints may also be glued although it is not necessary.Screwed butt joint
Butt joint with pocket hole screwsThis is a variation of the screwed butt joint in which the screws are inserted into pocket holes drilled in the rear face of one of the joint members.
Glue Blocks and BracesGlue blocks are commonly used inside plywood and MDF assemblies, like cabinets, dressers, armoires, etc. They can also be used on solid wood projects, as long as the glue blocks grain runs parallel to the grain of the assembly.
Nails and ScrewsAn easy way to strengthen carcass assemblies is to add nailsor screws, to hold the joints together while the glue dries.
Screws driven into the holes pull the parts together and secure them firmly. Pocket screwed butt joints are quick to assemble and require no glue, so theres no squeeze-out or messy drips to clean up afterwards.Pocket Screws