electromagnetic induction is what causes the fan to turn

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Since 15 December 2010

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JOINING WOOD

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TYPES OF JOINTS

Butt Dovetails Housed

Lap Rebate Tenon andmortise

Tongue and

groove

Strengthening

joints

Tips and

Tricks

When joining wood always use sharptools. Square all ends, edges and faces

before making a joint. Mark carefully

and always cut on the waste side of the

lines. (See: Mark and measure)

Choose the simplest joint suitable to the

work piece.

Butt joints back to top

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Butt joints are the easiest of all to make.Wood is butted face to edge or end to edge

and nailed, screwed or dowelled together.

End to edge joints can be joined withcorrugated fasteners.

Strength can be added by glueing the

joining faces. These joints are notrecommended for hardwood unless pilotholes and screws or dowels are used to

hold them together.

When nailing or srewing but joints use

corner or mitre clamps to hold the two pieces in place.

End to edge butt joint.



Lap or halved joints back to top

Halved joints or lap joints are mostlyused to assemble light frames which are

going to be covered with hardboard or plywood. Half the thickness of each piece

of wood to be joined is cut away with a

tenon saw and the joint is glued andscrewed or nailed. Halved lap joints are

also used to join long lengths of timber as

for fencing.

Tee half joint

Mitre joints back to top



Mitre joints are always cut to 45° in amitre box so that they will form a 90°

corner when joined. As no end wood is

ever seen these are very neat joints but

they are weak. Normally used for pictureframes where they are nailed with panel

pins. When used for other purposes theymust be strengthened with glue blocks,

angle braces or loose tongues. Mitre joints

should always be glued.

When nailing a mitre joint always start thenail with one part of the mitre above theother. The nails will pull the mitre intosquare.



Rebate joints back to top

Rebate joints are suitable for joining topand bottom ends of furniture. Stopped

rebate joints hide the joint. Glue and skewnail, or screw the joint together.

Stopped rebate joint

Housed joints back to top

Housed joints are mostly used for shelves.The stopped house joint hides the actual

joining. Use skew nails or screws to fasten



the boards together.

Stopped housed joint

Tongue and groove joints back to top

L

oose tongued joints are used to join planks edge to edge to form a larger board

like a table top in which case they are

always glued only.

Bare faced tongue and groove or Loose



tongue and groove joints can be used to

join chair rails to chair legs. Note the glue blocks for extra strength.

Tenon and mortise joints back to top



Tenon and mortise joints are very strong

joints mostly used in furniture making and

for heavy doors and gates. They are not

easy joints to make. The secret in makinga good tenon joint lies in careful andaccurate marking (See: Mark and

measure).The tenon¶s width should not beless than a third of the thickness of thewood especially if wood of the same

thickness is joined. The shoulders may be

of any width and may also be offset whenthe mortise is made in rebated wood.Make the mortise before rebating the

wood. If the top of the mortised wood is to

be in line with the edge of the tenoned

wood a haunched tenon can be made withthe haunch cut back to be in line with theshoulders.

Haunched tenon joint



Beveled haunched tenon

Marking and making mortise and tenon

joints.

1. Mark the depth of the tenon on both edges and faces of one of the pieces of wood.

2. Set the pins of the mortise gaugeto the width of the tenon and setthe block to the width of one



shoulder. Mark the tenon on the

edges and end of the wood.

3. Using the same settings of themortise gauge mark the mortise on

one side of the other piece of

wood.

4. Set the marking gauge to thecentre of the mortise and mark a

centre line.

5. When making a blind tenon drillholes (with a diameter slightly

smaller than the width of the

tenon) closely together along the

centre line at a depth slightly morethan the length of the tenon to

create an escape route for excessair and glue. A 1 mm (or smaller)hole can be drilled from the side

into the base of the mortise for thesame purpose. This hole can easilyand unobtrusively be filled with

wood filler or beeswax if

necessary. When making a

through tenon it is best to mark thetenon on both sides of the woodand to drill from both sides or to

watch and ³back drill´ to avoid

splintering the wood.

6. Remove excess wood with a sharp

chisel, always working from thecentre to the edges of the mortise.

Keep edges of the tenon andmortise as sharp as possible.

7. Place the wood from which thetenon has to be cut at a 45° anglein a vice and with a tenon saw

start cutting the tenon cheeks at

the highest point on the waste sideof the marking. When the depthline of the tenon is reached, turn

the wood around and finish cuttingfrom the other side. Then cut the

shoulders and lastly the haunch.

Remove excess wood with a sharpchisel till the tenon fits tightly inthe mortise.



8. Glue the two parts together.

9. A dowel or screw inserted from

the side may be used to strengthenthe join.

10. A through mortise can bestrengthened by inserting small

wedges in the opposite end of thewood to hold the tenon in place.

Marking a mortise

Bridle joints or open mortise and tenon

joints are used in furniture makingespecially to join the legs to the cross

pieces. Marked in the same way as mortise



and tenon joints the only difference is that

the mortise is cut into the wood from theend.

Dovetail joints back to top

Dovetail joints are very strong and neat

joints used primarily to make drawers and

boxes. It needs a lot of practice to make agood dovetail joint.



Marking for dovetail joints.

1. Square the ends of the wood to bedovetailed.

2. Set the sliding bevel to a suitable

pitch of between 1 in 6 for heavy

work and 1 in 8 for smaller andmore detailed work. Avoid sharp

angles as the points of tails break easily.

3. Scribe the tails on the end and faceof the wood and mark the ³waste´

pieces.

4. Clamp the wood in a vice and cuton the waste side with a tenon

saw.

5. Lay the two pieces over each other

and transfer the markings through

the cuts with a tenon saw.

6. Remove the waste between tails

and pins with a chisel.

Lapped dovetails are mostly used for



drawer fronts as they give a very neat,

strong joint with only one side showingend wood. Marking is the same as for opendovetails but the cutting out between the

pins needs a fair amount of chiseling.

Special dovetailing bits are available for

routers, which are ideal for this job.

Running dovetails

A very nice joint to use for fixing drawer sides to fronts but don't attempt it without

a router.

Strengthening joints back to top

Dowels aremostly used to

strengthen butt,mitre and rebated joints but are alsoused to join wood

when making or repairing small tables,chairs and doors. When joining wood to be

rebated or grooved, drill the holes for dowels first. The diameter of a dowel

should not be more than a third of the



width of the narrowest wood to be joined.

Cut the necessary length from dowel sticksand lightly chamfer the ends. Good dowelsticks have a ³V´ groove along the length

to allow excess glue and air to escape. If

your dowels do not have this groove you

can run one in by using a marking or mortise gauge. Alternatively you canallow a little space at the end of the hole in

which the dowel is inserted to allow for the extra glue and air but this will weaken

the joint.

When using dowels to join cross pieces tosmall legs, stagger the dowels for

maximum length and strength.

Glue blocks. Small pieces of quadrant or a length of quadrant run the entire length of the joint

make excellent glue blocks and give a neat

finish especially on the inside of drawersand boxes.

Angle braces are always glued and

screwed or nailed



Tips and tricks back to top

Tips and tricks When screwing into end wooddrill a hole and insert a dowel.

Then screw into the dowelthrough the end wood.

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A wood joint is the intersection where two pieces of wood are joined together.Moldings such as window and door casing, baseboards, crown molding andcabinets all have wood joints.

Read more: What Are Wood Joints? | eHow.com http://www.ehow.com/facts_5838122_wood- joints_.html#ixzz19oOP6GHR

electromagnetic induction is what causes the fan to turn

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