draft Marking out and measuring tools Item Name Use Advantages Disadvantages for measuring up to 300 mm in length

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1 Marking ou and measuring Chaper 2 Tools and equipmen Marking ou and measuring 34 Recognise and be able o selec he correc ools and equipmen when marking ou and measuring. Undersand he ools uses, advanages and disadvanages. Marking ou and measuring is a criical par of manufacuring and is usually subjec o a number of qualiy conrol checks. If componens are marked ou and measured wrongly before being cu ou, here is no chance of hem fiing ogeher when hey are assembled. Always ake marking ou measuremens from a daum as indicaed in Figure 2.1. A daum edge is a fla face or sraigh edge from which all measuremens are aken. This prevens cumulaive errors being made. If you are using imber, choose he face side carefully, before marking i wih a small symbol for idenificaion purposes, as shown in Figure 2.2. Then selec a face edge ha is a righ angles o he face side. Take all your measuremens from his side and/or edge. Daum B Daum A Figure 2.1: Daum edges face side Marking ou and measuring ools These are he ools used for marking ou and measuring ha you need o know abou: rules squares gauges scribers. punches emplaes micromeers Rules There are wo basic ypes of rule: seel rule and seel ape. Boh sar a zero and have millimere graduaions. face edge Figure 2.2: Face edges Iem Name Use Advanages Disadvanages seel rule for measuring up o 300 mm in lengh rigid form which means i will no bend and flex ends can ge worn, so he measuremens are no accurae measuring ape for making longer measuremens up o 5 m longer, so more versaile can become wised and break ends can break off, making hem useless Table 2.1: The uses of rules

2 Chaper 2 Tools and equipmen Squares There are a number of squares: ry square mire square engineer s square. Boh he ry square and engineer s square are used o mark lines a 90 o an edge. A ry square is used on imber and an engineer s square is used on meals. Boh can be used for marking ou plasics. You can also use ry squares and engineer s squares o check ha a cu or an edge has been made a righ angles o anoher. Hold he sock par of he square ighly agains he edge ha you have jus cu. If you can see ligh beween he wo edges hen he cu is no square. A mire square is used for marking ou 45 or 135 angles on wood and plasic. Take grea care when using any form of square for marking ou or checking, and ensure ha i is being held firmly and ighly agains he surfaces or edges of he maerial. Iem Name and use ry square marking ou or checking righ angles on wood or plasic engineer s square marking ou or checking righ angles on meal or plasic Srech Aciviy A ry square will usually have a brass face on he inside of he sock. Describe why here is a brass face on he sock raher han i being lef as wood. 35 mire square marking ou or checking angles of 45 or 135 Table 2.2: The uses of squares

3 Marking ou and measuring Gauges There are hree basic ypes of gauge: marking gauge cuing gauge. morise gauge 36 Suppor Aciviy Describe he difference beween a marking gauge and a cuing gauge. Apply I! In Uni 1: Make aciviy you should describe he use of marking ou ools. Keep a phoographic record of he sages of your manufacure in he secion on Qualiy of manufacure. Show all he relevan processes in deail, including he measuring and marking ou sages. Be careful no o confuse scribers and cenre punches. You hi a cenre punch wih a hammer; if you do his o a scriber, you will blun or break is ip. However, if you ry o use a punch for marking ou, i will no be as accurae. A marking gauge is used for marking lines parallel o he face edge and side on wood. I consiss of a sock ha slides up and down he sem, allowing various measuremens o be se. The gauge should be se using a seel rule ha has a zero end. The spur (sharp poin) is pushed ino he wood as he gauge is pushed or pulled along he lengh of he imber. I is imporan o hold he sock ighly agains he edge of he imber o ensure ha you mark a parallel line. A cuing gauge is used for cuing across he grain. I is used in he same way as a marking gauge, bu has a blade insead of a spur. The blade cus he fibres across he grain, making i easier and neaer o cu wih a saw. A morise gauge has wo pins; one pin is fixed and he oher is adjusable. I is used for marking wo parallel lines where a morise and enon join is o be cu. The process of marking ou is exacly he same as wih he wo oher gauges. Figure 2.3: Morise gauge Scribers A scriber is used o scrach he surface of meal and plasic lighly. If you are using a scriber on meal, i is a good idea o apply a coa of engineer s blue. This is a spiri-based liquid ha is applied o a meal surface. When he scriber is dragged across he engineer s blue i leaves a clean line, which can be easily seen. Figure 2.4: A scriber

4 Chaper 2 Tools and equipmen Punches Cenre punches are used o make an inden in he surface where holes are o be drilled in meal, as shown in Figure 2.5. They provide a saring poin for he drill and sop i skidding over he surface. Do punches are used for marking he cenres where dividers are o be used. They are similar o a cenre punch, excep ha he ips are ground o a 60 raher han a 90 poin. Quick noes Scribers are used o scrach he surfaces of meal and plasic. Punches are used o inden meal surfaces. Do no mix hese up. Srech Aciviy 37 Figure 2.5: A cenre punch, and he punch in use Templaes A emplae is used when a number of idenical shapes or paerns need o be marked ou. You can make a emplae from any hin maerial, such as plywood or aluminium, ha is easy o draw around. Micromeers A micromeer is a specialised insrumen used o ake very accurae measuremens. The himble, which roaes as he micromeer is ighened, has 50 equal divisions around is diameer, giving an accuracy of 0.01 mm. A reading is aken by adding all he visible whole numbers o he neares 0.5 mm. The reading from he himble, which will be beween 0 and 0.49 mm, is added o he main reading o ge he exac measuremen. Alhough he micromeer provides a very accurae measuremen, i can be difficul o learn how o read i. Figure 2.6: A micromeer Scribers and punches are made from a grade of seel known as ool seel or highcarbon seel. Invesigae why his is. Which properies of high-carbon seel make i suiable o be used in his way? Name he ool and describe is use. (2 marks, 2003) Basic answers (0 marks) Simply no able o recall he fac ha he ool shown is a micromeer or ha he ool is used for measuring or aking accurae measuremens. Good answers (1 2 marks) Tool is correcly idenified and named as a micromeer and i is correcly described as being used for measuring or aking accurae measuremens. Figure 2.7: The reading on his micromeer is = mm

5 Wasing Wasing 38 Recognise and be able o selec he correc ools when removing wase maerial during he manufacure of producs. Wasing ools A wasing process is one ha produces wase or unusable maerial by eiher cuing bis ou or cuing bis off. These are he ools used for wasing ha you need o know abou: saws planes chisels files drills abrading ools. Undersand he ools uses, advanages and disadvanages. Build Beer Answers Name he ool and describe is use. (2 marks) Saws Saws are used o cu maerial ha is no needed away from maerial which is. Saw blades have alernae eeh ben ou or se in opposie direcions. This is so ha when hey cu, hey make a gap, called he kerf. The kerf mus be wider han he saw blade so ha he blade canno ge suck. When using a saw, you should always cu o he wase side of he marked line so ha you leave a small amoun for finishing by eiher sanding or filing. Whaever you are cuing, i is imporan o keep as many eeh in conac wih he piece being cu as possible. You should choose he correc saw for he ype of maerial you are using. Table 2.3 on he nex page shows he mos common ypes of saws used in school workshops. Basic answers (0 marks) No able o recall he fac ha he ool shown is a enon saw or ha he ool is used for making sraigh cus in wood, or cuing enon joins and shoulders. Good answers (1 2 marks) Tool is correcly idenified and named as a enon saw and/or i is correcly described as being used for making sraigh cus in wood, or cuing enon joins and shoulders.

6 Chaper 2 Tools and equipmen Saw Name Use Advanages Disadvanages coping saw cu curves in wood and plasics has a hin, replaceable blade held in a frame wih he eeh poining backwards, owards he handle blade can be roaed easily o cu complex shapes and curves blade can be removed from he frame so ha pockes or windows can be cu ou blades easily broken due o heir size difficul o conrol when making sraigh cus blades can be pu in he wrong way round 39 enon saw he saw mos commonly used for cuing wood in he school workshop good generalpurpose woodworking saw deph of cu limied o deph of he blade mm long wih eeh/mm doveail saw adjusable hacksaw can be used o cu all general joins; specifically used o cu shoulder of enon in enon and morise joins used for small, accurae work such as doveail joins shorer han a enon saw wih eeh/mm has replaceable blade held in a frame blade can be angled o cu difficul shapes or if he frame ges in he way of he piece being cu blade can vary in lengh from 250 mm o 300 mm fine, accurae cu smaller eeh make i ideal for finer work can be used o make sraigh cus in plasic and meal blade can be removed from frame o cu windows or pockes ou only appropriae for fine work no robus enough for general purpose work blades can snap or wis easily blades can be pu back in he wrong way round eeh face forwards and blades have eeh/mm can be used for fine work or rough cuing ou Table 2.3: The mos common ypes of workshop saws Suppor Aciviy Try cuing a square hole in a piece of plywood. Firs drill some holes in he wood so ha you can pass he coping saw blade hrough i. Srech Aciviy Try o work ou why i is beer o have he eeh of he blade facing backwards owards he handle.

7 Wasing 40 Planes Planes are used o smooh wood fla and o reduce o size. A jack plane is longer and heavier han a smoohing plane, which is used for finishing and planing end grain because i is easier o handle han a jack plane. A block plane is he smalles plane and is generally used for removing sharp edges and for puing a small bevel along an edge. Plane Name Use Advanages Disadvanages jack plane smoohs and flaens wood o size long and heavy so ideal for creaing a fla surface easily jammed if no correcly se heavy smoohing plane finishing a surface and for use on end grain ideal for use on end grain due o is lengh easily jammed if no correcly se Table 2.4: Common workshop planes block plane removes sharp edges and makes a bevelled edge can be used in one hand easy o creae small bevels easily jammed if no correcly se no effecive on large fla surfaces Planing end grain Wase wood Planing a narrow edge Apply I! If necessary in Uni 1: Make aciviy, use a plane in he direcion of he grain. When planing end grain, use a piece of scrap wood o preven spliing, or plane ino he cenre from boh sides. Figure 2.8 shows how o do his. Planing wih he grain Bench sop Figure 2.8: Planing

8 Chaper 2 Tools and equipmen Chisels Wood Four basic wood chisels are used in he school workshop: he firmer chisel is a general-purpose chisel, which has a square edge a bevel-edge chisel has a bevelled blade ha allows i o ge ino corners and is especially useful for cuing doveails morise chisels have much deeper blades and are used wih a malle for cuing morise joins gouges have curved blades and are used for carving. Firmer chisel Figure 2.9: Chisels Bevel-edge chisel Morise chisel Gouge Meal Cold chisels can be used o cu shee meal, eiher by shearing across i or by chopping down on i verically. They have a hardened and empered cuing edge while he oher end is lef sof o absorb he impac from he hammer blows. Differen profiles are available, allowing access o corners or for producing grooves in he workpiece. Abrading ools Abrading ools remove very small paricles of wase, such as hose produced by filing. Abrading ools include rasps, which are used on wood, and surforms. Surforms have replaceable blades. They are formed and operae a bi like a cheese graer. Abrasive papers are also available for wood, meal and plasics. Glasspaper, someimes called sandpaper, is used on wood and is made from glass paricles suck o a hick paper shee. The paper is graded according o how much gri here is per uni area. Emery cloh is used on meals and plasics and i is graded in he same way as glasspaper. Any form of abrasive paper is bes used wrapped around a cork block. This ensures ha an even pressure is applied over he work. Suppor Aciviy Lis hree healh and safey risks associaed wih using a firmer chisel in he school workshop. Quick noes Each wasing ool is used for a very paricular use. For example: planes smooh and finish wood chisels carve and cu meal or wood abrading ools remove small paricles of wase. Srech Aciviy Use he inerne o find ou how sandpaper is made. 41 Abrading ool Name Use Advanages Disadvanages rasp quick removal of wase wood can be used like a file o creae exernal curves good on fla edges and surfaces clogs up easily surform fas removal of sof maerial can be used on fla or 3D surfaces blades can break easily Table 2.5: Common workshop abrading ools

9 Wasing 42 hand file half round file square file handle fla file safe edge Figure 2.10: Files ferrule ang round file riangular or hree square file lengh warding file Files Two basic filing processes are used in he workshop: cross-filing draw-filing. Cross-filing removes wase rapidly. You should use he whole lengh of he file wih a downwards force. The file only cus forwards. I should be lifed off a he end of he sroke and no dragged back across he workpiece. Draw-filing removes marks in he work lef as a resul of cross-filing. This mehod gives a much beer surface finish, and a smooher file should always be used for draw-filing. An even finer finish can be obained by wrapping a piece of emery cloh or we and dry paper around he file and repeaing he acion. Files are made from high-carbon seel. The main body is hardened and empered and has rows of eeh. The ang of he file is lef sof and fis ino he handle. General work is carried ou wih a fla file. One of he long edges has eeh; he oher is plain and is known as a safe edge. The safe edge prevens cuing ino he face of a square corner. Files wih differen profiles are available for a range of applicaions. There are also oher, more specialis forms of file. File Name Use Advanages Disadvanages fla file removes wase on large, fla surfaces quickly can be used o creae exernal curves has a safe edge on one side o preven cuing ino edge when filing a corner brile and easily broken if dropped eeh clog when filing sof maerial such as brass and aluminium (called pinning) round file creaes curves and filles increases in diameer along he lengh so can be used on differensized holes small cross-secion makes i weak and easily broken hree square file cus ino corners less han 90 useful beween angles of 60 and 90 canno file angles smaller han 60 Table 2.6: Common workshop files

10 Chaper 2 Tools and equipmen Drills Twis drills, he mos common ype of drill used in school workshops, can creae holes in mos maerials. There are many oher forms of drill, each wih is own specific use and applicaion. The mos common ypes used in school workshops are shown below. 43 Drill Name Use Advanages Disadvanages wis drill wis or flue carries wase maerial away in he form of swarf smaller sizes can be used in a hand drill available in sizes from 0.5 mm diameer o over 25 mm small drills prone o breaking if no used correcly fla bi counersink bi hole saw used o drill a hole all he way hrough, bu will break hrough, splinering wood on underside creaes depression for head of a counersunk screw so ha i sis flush wih surface of maerial used on hin maerials or o make large hole up o 150 mm in diameer used in elecric drill fas removal of wase wih an elecric drill can be used o creae range of counersunk hole sizes widely used by plumbers and elecricians o make holes for pipes and ducing can be used on hick and hin secions of wood and plasic will spli wood on underside when drill breaks hrough if no suppored by anoher piece of wood will chaer if used a oo high a speed have endency o burn if used a oo high a speed only come in se sizes Table 2.7: Common workshop drills and bis Name he ool shown here. (1 mark, 2007) How sudens answered The overwhelming majoriy of sudens scored very well on his quesion. Drill, drill bi and wis drill were all good answers for 1 mark. 85% go 1 mark

11 Exam Zone examzone Know Zone Chaper 2 Tools and equipmen 44 You mus use ools and equipmen correcly when carrying ou any manufacuring processes in he workshop. Using he correc ool for he job will help you o measure and mark ou successfully and accuraely. Careful ool selecion when carrying ou a wasing process will help you o remove maerial safely and appropriaely. You should know he following abou he lised ools and iems: Tool Appearance Uses Processes Advanages and disadvanages Rules Squares Gauges Scribers Punches Templaes Micromeers he following abou he lised wasing ools: Wasing ool Appearance Uses Processes Advanages and disadvanages Saws Planes Chisels Files Drills Abrading ools Muliple-choice quesions Which of he following is no a ype of gauge? A marking B measuring C morise D cuing Which ype of saw is shown below? A coping saw B doveail saw C jigsaw D adjusable hacksaw

12 Maximise your marks A suden needs o mark ou 10 idenical copies of he shape. Exam Zone The shape is marked ou ono an acrylic shee using a emplae and a marking-ou ool. 45 (i) Name one marking-ou ool ha can be used o mark around he emplae (1 mark, 2007) Suden answer Examiner conens Build a beer answer Ruler (0 marks) Scriber (1 mark) This shows a basic lack of undersanding of wha he quesion is asking for, and he suden has no grasped he concep ha a emplae is being used and i needs o be marked around. The scriber is he mos appropriae ool o be used since is sharp poin will make a visible scrach in he surface of he acrylic. A sraighforward response is required, naming he correc ool. The mos common response seen. Overall commen: This is a very sraighforward quesion. I relies on your abiliy o learn and recall facual knowledge. Here you are being asked o apply your knowledge and undersanding o an unfamiliar siuaion. I was very surprising o see ha only 30% of sudens scored he 1 mark available for his quesion. Pracice exam quesions 1. Complee he able below which shows some ools by filling in he missing names and uses. Tool Name Use ape plane marking ou wo parallel lines on wood making very accurae measuremens