Transcript WORKING WITH MATERIALS - University of KwaZulu
WORKING WITH MATERIALS
JOINING WOOD
FLAT FRAMED JOINTS
Basis for doors, window frames, sides of cupboards and picture frames be mindful of twisting when assembling members Tee joints and cross joints Butt joints – simplest- relatively weak joint – small glueing area mitre joints- picture frame – allows flow of moulding around corner - 45º nail/staple
FLAT FRAMED JOINTS
Halving joints – corner ,tee and cross halving. Removal of half thickness of material-tenon saw and firmer chisel.
Bridle joints – corner and tee joints added strength Dowel joints-circular sectioned hardwood – made from beech- need to be accurate –usually two dowels at each joint, the end are chamfered for easy insertion.
FLAT FRAMED JOINTS
Mortise and tenon – relatively strong joint- tee, through or stopped joint – used in high class furniture making Made using a tenon saw and mortise chisel. Marking is done with a mortise gauge
BOX JOINTS
Kitchen furniture, bedroom furniture, bookshelves, jewellery boxes, cupboard drawers – box shape.
Often made from manufactured board.
Why? Wide solid wood often shrinks and warps. Limit to available sizes Chipboard-little mechanical strength Blockboard-little stronger and requires edging just like chipboard
BOX JOINTS
BUTT JOINTS – not very strong therefore reinforced using dovetail nailing/glue blocks and/or screws LAP JOINTS – corner rebate joints – stronger and neater than but joints – less exposed end grain.
DOVETAIL JOINTS p31 notes
Strongest box corner joints – attractive properties of a large glueing area and assembly Can only be assembled/pulled apart in one direction – joint at right angles
COMB JOINTS(FINGER) Just like dovetails but easier to make- has a large glueing area and is attractive.
DOWEL JOINTS- added strength HOUSING JOINT – shelves and partitions
EDGING AND JOINTING
Edging is done to make manufactured boards more attractive and prevent the absorption of moisture. Wood as well as melamine edging can be used BUTT jointed Tongue and groove Loose tongue and groove Dowelled
WOODSCREWS
TEMPORARY fixing method because they can be removed when necessary – generally strong and neat.
Types of screws– countersunk, round head, raised countersunk, twinfast screws Screw driver slots-cross, pozidriv, phillips or supadriv Caps cups and mirror screws – hide or to enhance looks NB. Hints for screwing on P 33
KNOCK DOWN JOINTS
Usually used for flat pack furniture Corner blocks- used for light construction Frame connectors –used in assembling flat pack furniture legs
NAILS
Permanent method of joining wood Types of nails – round wire, oval wire, masonary and panel pins See sizes on P34 of notes NB. Hints for nailing P34
FINISHING
Final stage Sand paper French polish Oil Polyurethane varnish Paint END