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TRANSCRIPT
SEPTEMBER 2013 Technical Guide
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TECHNICAL GUIDEGUIDE
Keep this Technical Guide by your side.
It’s packed full of technical hints and tips!
Order online at cooksongold.comcall 0845 100 1122 or visit our Trade Counters
FAQs
Cleaning
& Finishing
Start Soldering
Table of comparative weights
Unit conversion
Metal gauge conversion chart
Ring sizing
Cooksongold Cheat Sheet
1598 Student Tech Guide 2013 A5_AW.indd 1 30/08/2013 09:33
ERE AT COOKSONGOLD, we don’t just provide you with everything for the jewellery maker (and, of course, the jewellery making student!) delivered next day.
Our years of experience in the industry also make us an invaluable source of hints, tips and useful advice whether you’re a student taking their fi rst steps in jewellery making or coming to the end of your course.
Either way, you’ll fi nd our Technical Guide a constant and essential companion in helping you make sure you get things right both in your student days and beyond.
H
FAQs:FAQs:FAQs:FAQs:FAQs:Why do I have to use di� erent tweezers when using pickle and soldering?If you use ferrous metal tweezers in pickle the copper oxides in the pickle will become suspended in the solution. This can cause your pieces to be contaminated and the silver to be plated with copper.
To stop this from happening make sure you use either brass or plastic tweezers to remove your pieces from the pickle. The same reaction happens if you leave the binding wire on, so be careful to remove it before pickling.
Why do youanneal? Annealing is doneby heating themetal, making itsoft so you canshape it further.You must annealin betweenforming metalto make sure youdon’t crack the metal as you work with it.
Should I be using a mask whileI polish? Use a mask and protective goggles to protect your eyes.
What can I use to protect my fi ngers while polishing? Use fi nger tape, wrap it around your fi ngers fi rmly but make sure you’ve still got plenty of movement. This will protect your fi ngers but allow you to polish.
What does pickle do? It removes oxides and dirt from the surface of precious metal after soldering.
Why do you have to use di� erent grades of emery paper? Different grades of emery paper remove scratches from the surface. You’ll need to work down through the grades from coarse to fi ne. Once you’ve reached the fi nest, the surface will be ready for polishing.
Why do you have to use di� erent grades of fi les? What’s the di� erence?This is a way of removing excess metal more quickly than using emery paper. Cut 00 (very coarse), Cut 2 (medium) and Cut 4 (fi ne). Different shapes can be useful for different sections of fi les. Triangular fi les in section are useful when fi ling ‘tight’ corners/angles; sharp edges allow the fi le to fi t into corners when fi ling. Half round fi les are used for fi ling curved surfaces and are especially useful for fi ling internal curves.
How can I prolong the life of my fi les? Make sure you fi le away from yourself. Using a backwards/forwards motion will blunt the fi le. Keep fi les clean using a fi le brush and store in a dry place.
What’s a vernier gauge?This is used to get a precise measurement of a thickness of metal. It can be used to get internal or external dimensions.
What are the benefi ts of the di� erent solders?Hard solder is best for the majority of soldering as it has the closest colour match to silver. To do multiple joints you should go down through the grades from hard through medium to easy and extra easy as they have lower melting points as you go down the
grades. Also easy solder can be used for fi ne joins that need to keep heat to a minimum.
How do I change a saw blade? Make sure you put the saw blade in so that the teeth face downwards. Check the tension before sawing. If it’s too loose, the blade will snap and not saw smoothly.
How can I create a polished fi nish on a hard to reach area? Use a burnisher. We offer a range of sizes, curved or straight, to reach different parts of your piece.
What’s the di� erence between the rawhide mallet and a metal hammer?It causes less damage to the work piece and is less noisy. A metal hammer will move and stretch the metal further than a rawhide so use a metal hammer if you want to fl atten out the end of a wire.
I’m having trouble deciding how much silver sheet to buy for a bangle. How do I go about sizing?We would suggest a thickness of 0.9mm to 1mm for a standard bangle and then decide how wide to go. Consider whether you want a really chunky piece or something more slender. As for the length, close your hand as tightly as possible and measure the distance across it and this will give you the diameter you need. Standard bangles are generally 80mm in diameter so you would need to multiply this by Pi (3.14) to get the circumference and the length needed which in this case would be about 250mm.
What can I use to hold my work in place while I solder? Third hands are great for using the reverse action tweezers as you can get precision holding metal in place but you won’t get burnt while you solder.
Third hand
Tweezers
Annealing is done
don’t crack the metal as you work with it.
or super duper!
Regular...
2 3Order online at cooksongold.com, call 0845 100 1122 or visit our Trade Counters
Pickling
Mau
ro C
ateb
a silver stripAnnealing
Mau
ro C
ateb
Usegoggles
andgloves
1598 Student Tech Guide 2013 A5_AW.indd 2-3 30/08/2013 09:33
Cleaningand fi nishing
What if I can’t get into the area with wet and dry? Use abrasive tape/crocus cord. This is like wet and dry string and can be used to thread into holes and other hard to reach areas such as settings. It’s currently only available in fi ne with different thicknesses - 2.38mm (998 168), 1.02mm (998 170) and 0.38mm (998 210).
Radial Abrasive discs. We sell a great value set (999 1967) containing 6 pieces of 3 grades or 2 of each grade when made up. These are great for cleaning details without being too harsh with the bristles allowing the discs to get into the
grooves and fi ne details of a piece.
Polishingmops for apendant motor. Madeof calico/cotton and felt, on page 534 you’ll fi nd the different shapes we have available. Always use a different mop for each compound. Start with a general compound (999 2093) small bar. This is good for most metals. Then rouge (998 189) small bar for fi nal stage polishing.
Ultrasonic. This is to removethe polishing compound ateach stage and at the end ofpolishing. Use an ultrasoniccleaner like 997 1306.This can be used withsea clean (999 AKJ1)for more effectivecleaning.
How does anUltrasonic work?This piece of equipment uses ultrasonic waves. The vibration generated creates tiny bubbles that lift the dirt gently away from the piece. This is useful for getting the polishing compound out of awkward areas. Do not put porous items in the tank.
What if I can’tget into a small area after polishing?We sell a product called polishing thread (999 CBA) which is like a string that can be used in a similar way to fl oss to get into holes and around settings.
Once all the scratches have been removed there are several options:
Polishing pads (998 027B) are used to remove
tarnish. Abrasive pads
(975 125) can be used dry or with
water. These are fl exible rubber pads used for sanding,
pre bonded with aluminium oxide abrasives. Sanding pads (999 SS01) are similar to wet and dry. If you rinse them after each use they should last much longer compared with wet and dry.
This is to ensure that all the scratches are removed or reduced at each grade. Have you tried the wet and dry sticks? (999 FAJ is ahalf round).
Thesesticks aregreat for moreprecise work and thehalf round is ideal for inside rings.
Pumice canbe used oncethe piece hasbeen rinsedafter being in the pickle. (998 224). It is not really essential but is a good start to the cleaning and fi nishing process. It can be used with a nail brush to scrub the item quite vigorously (if the piece is not too delicate of course). A toothbrush can also be used to get into harder to reach areas. The green scouring pads used for dishes are great to use with pumice as they are really fl exible.
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Wet and Dry. Good practice is to go through the grades from 240 (975 020),320 (975 030),400 (975 500),600 (975 060),800 (975 070),1000 (975 080),to 1200 (975 090).
removed there are several options:
Pendant Motor. An essential piece of kit! Use with various attachments for cleaning-up. From sander rolls and abrasive discs to polishing mops, this tool offers an even and effi cient fi nish.
Rubber burrs. These can be used alongside or instead of wet and dry. The different shapes available are: Blue (coarse) - hard yet fl exible. Grey (medium) - suitable for trimming
castings. Brown (fi ne) - creates a matt fi nish. Green (extra fi ne) - for high lustre polishing.
Duo polishing cloth(998 026), one fornatural shine, one for super shine. Can be used for removing fi nger prints and general cleaning. It will also remove tarnish.
away from the piece. This is useful for getting the polishing compound out of awkward areas. Do not put porous items in the tank.
What if I can’t
Again, good for mostmetals. Then blueDialux for fi nepolishing (999 217).Then grey Dialuxfor superfi nefi nishing (998 218).
Brass Brush. This is a quick and easy way to brighten up the metal. Use with a detergent such as a grease-removing washing up liquid. The brush must be used with soap especially on silver to help prevent the brass leaving yellow marks.
there are a couple of options for cleaning:
After soldering and pickling
1598 Student Tech Guide 2013 A5_AW.indd 4-5 30/08/2013 09:34
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Boraxdish (for mixing the borax). If you’re new to soldering, it will
take a little while to get the consistency right. Just add a little water and grind the cone in the dish. It should achieve the consistency of single cream. Then apply the fl ux to the join and over a little of the surrounding area (999 AAI).
Flux Brush. This is not a special brush. This particular brush is just less likely to leave behind bristles which can contaminate the join as the fl ux is brushed on (bristles are bad because they can contaminate the join as they burn).
Torch. Again, if you’re new to soldering, we recommend a hand torch. You can also get the gas from us. Or, if you’re a student starting out in a more professional capacity, the Sievert Torch Kit is a good starting torch (999 AKZ1) and the gas can be bought fromDIY stores.
Soldering block. This is to solder on. Don’t use normal bricks as they will absorb the heat away from the piecepreventing the pieceto be solderedfrom gettinghot enough.
Pickle. You’llneed this once thepiece has been soldered:1. Because the fl ux will have left sections of the piece covered in a glassy hard substance which would be diffi cult to get off otherwise and 2. Because the piece is likely to be ‘fi re stained’. When you heat metal to a high enough temperature, the
copper in the metal will react with the oxygen in the air and
oxidise. This turns the metal black. There’s a high content of copper in 925 sterling silver. The acid pickle will strip away the black surface
Start Soldering
There are two general techniques used to apply solid solder:
What you will need:
1: PreplacementSmall pieces of solder are placed at the joint seam prior to heating. Heat is then applied until the solder fl ows into the joint.
2: FeedingThe fl uxed joint is heated to temperature and the tip of the solder wire is fed into the joint and should melt on contact.
Using both these techniques, the part of the joint at which the molten solder is required should be heated more strongly than the remainder ensuring the solder will fl ow towards the hottest section. Continued fl ame impingement on the molten solder may result in the vaporisation of lower melting point constituents. Higher temperatures may then be required to complete the joint. The time and temperature required to complete a joint must be kept to a minimum.
Firestain occurs when the copper contained in silver alloys is oxidised during annealing or soldering.Light fi restaining can usually be polished out, or may respond to pickling in a bathof 10% sulphuric acid or another proprietary pickle. However, silver plating may be the only answer to heavy fi restain.
If a protective atmosphere is NOT available to carry out annealing operations, the following steps canbe taken.Avoid prolonged heating wherever possible. Ensure that a large enough fl ame is usedto get soldering and annealing jobscompleted in the minimum amount oftime. The entire workpiece can be coatedwith a fl ux which will form a glassy coaton the metal, protecting it from theatmosphere. Use a large, bushy fl amewhen annealing, allowing the job to becompleted quickly and providing a slightly reducing atmosphere.
but may leave something called fi restain which looks like a shadow on the surface and is essentially a stain. The only way to get rid of this is to either fi le it out – using wet and dry or the new radial discs. Our kit (999 1967) has 2 of each grade which can be used with the pendant motor.
Pickle unit (999 AFD). This is the cheapest we stock. A glass container can also be used in a warm water bath. The pickle should be used warm to speed up the process. When the item comes out of the pickle it will be white in appearance.
6
Chain link soldering
It can then be rinsed and cleaned with pumice (998 224) then wet and dry through the grades. Then it can be polished etc. It can also be fi nished with a brass brush (999 173) which will brighten up the metal after the wetand dry.
Sheet annealing
Usegoggles
andgloves
Solder. If you are soldering non precious metal, use the easysolder then go up to medium etc. for each separate soldering jobon the same piece (thepiece needs to be cleanedbetween each soldering).
Borax. This is a natural mineralwith the least toxic fl ux whichabsorbs oxygen to create abetter environment for thesolder to fl ow in. (998 098).
1598 Student Tech Guide 2013 A5_AW.indd 6-7 30/08/2013 09:34
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Table ofcomparativeweights
Table ofTable ofTable of Unitconversion
Multiply the known unit by the fi gure to the right of the measurement you desire. For instance, how many grains are in 3 carats?
The model of a man’s signet ring has been made out of silver and weighs 7.9 grammes. Looking at the table along the Sterling Silver horizontal line and then matching this with the intersection of the 18ct Yellow Gold HB gives the number 1.50.
Known x # from chart = Answer 3 x 3.0865 = 9.2595
7.90 grammes x 1.50 =11.85 grammes in Yellow HB Gold
Carats to grains x 3.0865 to grams x 0.2 to milligrams x 200
Grains to carats x 0.324 to grams x 0.0648 to milligrams x 64.799 to oz, avoir x 0.002286 to oz, troy x 0.00208 to pennyweight x 0.04167
Grams to carats x 5 to grains x 15.4324 to oz, avoir x 0.03527 to oz, troy x 0.03215 to pennyweight x 0.64301
Kilograms to oz, avoir x 35.274 to oz, troy x 32.1507 to pennyweight x 643.015 to lb, avoir x 2.2046 to lb, troy x 2.6792
Oz, to grains x 437.5Avoirdupois to grams x 28.3495 to oz, troy x 0.91146 to pennyweight x 18.2291 to lb, troy x 0.07595
Oz, to grains x 480Troy to grams x 31.1035 to oz, avoir x 1.0971 to pennyweight x 20 to lb, avoir x 0.06857
Pennyweights to grains x 24 to grams x 1.5551 to oz, avoir x 0.05486
Lbs, to grains x 7000Avoirdupois to grams x 453.59 to kilograms x 0.4536 to oz, troy x 14.5833
Lbs, to grains x 480Troy to grams x 31.1035 to oz, avoir x 1.0971 to pennyweight x 20 to lb, avoir x 0.06857
Feet to centimetres x 30.48 to metres x 0.3048
Metres to feet x 3.2808 to inches x 29.37 to yards x 1.0936
Millimetres to feet x 0.00328 to inches x 0.03937 to centimetres x 2.54 to metres x 0.0254
Cubic cm to cubic inches x 0.061 to US Fl. oz. x 0.0338
Cubic inches to cubic cm x 16.387 to litres x 0.01639 to US Fl. oz. x 0.554
US gallons to litres x 3.785 to cubic inches x 231 to cubic feet x 0.1337
Litres to US gallons x 0.2642 to US quarts x 1.0567
Useful information for every year of your course:To use the table below, simply take the unit fi gure of the metal to which comparison is required and then follow the line to the right or left of this fi gure that is the relative weight unit for the chosen metal. Typically, a Silver model may be made for subsequent casting using the cuttlefi sh method producing a casting in 18ct Yellow Gold HB.
For example...For example...
Pu
reP
lati
nu
m
Fin
eG
old
22
ct D
S
18ct
MW
18ct
HB
14ct
AY
GW
Pal
lad
ium
9ct
DF
Ste
rlin
gS
ilv
er
Co
pp
er
Bra
ss(9
0/1
0)
Wa
x
Pure 1.00 0.90 0.83 0.75 0.72 0.60 0.54 0.52 0.48 0.42 0.40 0.05PlatinumFine 1.11 1.00 0.92 0.84 0.80 0.67 0.60 0.58 0.53 0.47 0.45 0.05Gold22ct DS 1.21 1.08 1.00 0.91 0.87 0.73 0.66 0.63 0.58 0.51 0.49 0.06
18ct MW 1.33 1.19 1.10 1.00 0.96 0.80 0.72 0.69 0.64 0.56 0.54 0.06
18ct HB 1.39 1.25 1.15 1.05 1.00 0.84 0.75 0.72 0.66 0.58 0.56 0.06
14ct AY 1.65 1.48 1.37 1.25 1.19 1.00 0.90 0.86 0.79 0.69 0.67 0.08
GW 1.84 1.65 1.52 1.39 1.32 1.11 1.00 0.96 0.88 0.77 0.75 0.09Palladium9ct DF 1.92 1.72 1.59 1.45 1.38 1.16 1.04 1.00 0.92 0.80 0.78 0.09
Sterling 2.09 1.87 1.73 1.57 1.50 1.26 1.14 1.09 1.00 0.87 0.84 0.10SilverCopper 2.39 2.14 1.98 1.80 1.72 1.44 1.29 1.24 1.14 1.00 0.97 0.11
Brass 2.47 2.22 2.05 1.86 1.78 1.49 1.35 1.29 1.18 1.03 1.00 0.11(90/10)Wax 21.30 19.30 17.80 16.20 15.50 13.00 11.70 11.20 10.30 9.00 8.70 1.00
1598 Student Tech Guide 2013 A5_AW.indd 8-9 30/08/2013 09:34
Metal gauge conversion chart
0.001 0.025 -0.0012 0.03 -0.0016 0.04 -0.002 0.05 -0.0024 0.06 -0.0028 0.07 -0.0032 0.08 -0.0036 0.09 -0.004 0.10 -0.0044 0.11 -0.0048 0.12 -0.005 0.12 -0.0052 0.13 -0.006 0.15 -0.0065 0.17 -0.0068 0.17 -0.007 0.18 -0.0076 0.19 -0.008 0.20 -0.0084 0.21 -0.0085 0.22 10.009 0.23 -0.0092 0.23 -0.0095 0.24 20.010 0.25 -0.0105 0.27 30.0108 0.27 -0.011 0.28 -0.0116 0.30 -0.012 0.31 40.0124 0.32 -0.013 0.33 -0.0136 0.35 -0.014 0.36 50.0148 0.38 -0.015 0.38 -0.016 0.41 60.0164 0.42 -0.017 0.43 -0.018 0.46 -0.0185 0.47 -0.019 0.48 70.020 0.51 -0.0215 0.55 80.022 0.56 -0.024 0.61 9
0.025 0.64 -0.027 0.69 -0.028 0.71 100.030 0.76 -0.032 0.81 110.033 0.84 -0.035 0.89 120.036 0.91 -0.038 0.97 130.039 0.99 -0.040 1.02 -0.042 1.07 -0.043 1.09 140.046 1.17 -0.048 1.22 150.049 1.24 -0.051 1.30 160.055 1.40 170.056 1.42 -0.058 1.47 -0.059 1.50 180.060 1.52 -0.062 1.58 190.064 1.63 -0.065 1.65 200.067 1.70 -0.069 1.75 210.072 1.83 -0.073 1.85 220.074 1.88 -0.077 1.96 230.080 2.03 -0.082 2.08 240.083 2.11 -0.086 2.18 -0.090 2.29 250.091 2.31 -0.092 2.34 -0.095 2.41 -0.0966 2.44 -0.100 2.54 260.102 2.59 -0.104 2.64 -0.109 2.77 -0.110 2.79 -0.112 2.85 270.116 2.95 -0.120 3.05 -0.121 3.07 -0.124 3.15 280.128 3.25 -0.134 3.40 -
Nearest metric BirminghamInch equivalent metal gauge
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Ring sizing
A 12.1 0.48 37.5 38 12.1 0.48A½ 12.3 0.48 38.4 39 12.4 0.49B 12.5 0.49 39.0B½ 12.7 0.50 39.6 40 12.7 0.50C 12.9 0.51 40.2C½ 41 13.1 0.51 40.8D 13.2 0.52 41.4 42 13.4 0.53D½ 13.4 0.53 42.0E 13.6 0.54 42.6 43 13.7 0.54E½ 13.8 0.54 43.2 44 14.0 0.55F 14.0 0.55 43.8F½ 14.2 0.56 44.4 45 14.3 0.56G 14.4 0.57 45.0G½ 14.6 0.58 45.6 46 14.6 0.58H 14.8 0.58 46.2 47 15.0 0.59H½ 15.0 0.59 46.8I 15.2 0.60 47.4 48 15.3 0.60I½ 15.4 0.61 48.0 49 15.6 0.61J 15.6 0.61 48.6J½ 15.8 0.62 49.2 50 15.9 0.63K 16.0 0.63 49.8K½ 16.2 0.64 50.4 51 16.2 0.64L 16.4 0.65 51.0 52 16.6 0.65L½ 16.6 0.65 51.6M 16.8 0.66 52.2 53 16.9 0.66M½ 17.0 0.67 52.8N 17.2 0.68 53.5 54 17.2 0.68
N½ 17.4 0.68 54.1 55 17.5 0.69O 17.6 0.69 54.7O½ 17.8 0.70 55.4 56 17.8 0.70P 18.0 0.71 56.0 57 18.1 0.71P½ 18.2 0.72 56.7Q 18.4 0.72 57.3 58 18.5 0.73Q½ 18.6 0.73 57.9R 18.8 0.74 5 59 18.8 0.74R½ 19.0 0.75 59.2 60 19.1 0.75S 19.2 0.75 59.9S½ 19.4 0.76 60.5 61 19.4 0.76T 19.5 0.77 61.1 62 19.7 0.78T½ 19.7 0.78 61.8U 19.9 0.79 62.4 63 20.1 0.79U½ 20.1 0.79 63.0V 20.3 0.80 63.7 64 20.4 0.80V½ 20.5 0.81 64.3 65 20.7 0.81W 20.7 0.82 64.9W½ 20.9 0.82 65.5 66 21.0 0.83X 21.1 0.83 66.1X½ 21.3 0.84 66.7 67 21.3 0.84 66.7Y 21.5 0.85 67.3 68 21.6 0.85Y½ 21.7 0.85 67.9Z 21.9 0.86 68.5 69 22.0 0.86Z½ 22.1 0.87Z+1 22.3 0.88Z+2 22.7 0.89Z+3 23.1 0.91
Bri
tish
Eu
ro
mm
ins
mm
Bri
tish
Eu
ro
mm
ins
mm
Finger Internal Internal size dia. circum.
Finger Internal Internal size dia. circum.
10
1598 Student Tech Guide 2013 A5_AW.indd 10-11 30/08/2013 09:34
Cooksongold Cheat Sheet
Saw blades • Different grades for different metals of
varying thicknesses depending on the intricacy of the piercing.
• Starting out, use 2/0 or 3/0 blades. Remember: the higher the number, the fi ner the blade, with the fi nest suitable for delicate work or thin metal. Generally, three ‘teeth’ of the saw should be the same as the thickness of the material.
• For best results, use no tension or force and simply allow the blade to glide smoothly. Using a little beeswax can help.
• And don’t forget: practice makes perfect when it comes to not breaking saw blades every few minutes!
Files • Files come in various forms: standard
(great for general shaping and tidying), needle (small fi les for more detailed work and tidying up) and escapement (tiny fi les for delicate work, often used by horologists).
• The different sizes also come in varying grades, from 00 (coarse) to 4 (fi ne). Cut 2 is a great all-purpose starter fi le.
• Use the fi le with a wooden handle, in a smooth forward motion, then lift the fi le and repeat - pulling the fi le towards you can blunt the fi le.
• To keep the fi le clean and unclogged, use a fi le brush with water and washing up liquid.
Solder • Silver solder can be used on silver and
base metals, such as brass and copper; other precious metals, like gold and platinum, have their own solders.
• Most students start with strips of silver solder which also comes in wire and paste form.
• Strip and wire need to be used with a fl ux which allows the solder to fl ow, whereas paste comes prepared with fl ux and is ready to use.
• Silver solder comes in hard, medium, easy and extra easy. Hard solder is the thickest and has the highest melting point. By using this fi rst you can then follow with medium and easy for further soldering, so the previous solder won’t melt.
Finishing • Emery paper: use dry.
• Wet & Dry paper.
Low number: Coarse.High number: Fine.
For best results, work through grade by grade, though you can skip one or two.
Can be used on wooden sticks, similar to using a fi le, or on a fl at even surface.
After going through the grades, the metal is ready for fi nal fi nish, e.g., polishing.
E KNOW THAT starting out in jewellery making can be a steep learning curve, so here
at Cooksongold we’ve put together our own special cheat sheet with all the basic things that you (and we!) sometimes need a little help remembering, like which solder is which and what grade of fi le to use. And don’t forget, we’re always happy to help, so just pop in and ask!
W
00
0
1
2
3
4
Files
Grade 4
Grade 3
Grade 2
Grade 1
1/0
2/0
3/0
4/0
5/0
6/0
8/0
Sawblades
240
320
400
600
800
1000
1200
Wet & Dry
150
180
240
500
1200
2000
Emery
CoarseFine
01
MM
CM
08
02
09
150
310
160
411
170
512
180
714
20
06
1319
01
03
05
07
02
04
06
08
16th
s10
ths
INC
HE
S
Positio
nal
When you are fi nished with this magazine please pass it on to a friend or neighbour, or recycle it. Thanx ;-)
1598 Student Tech Guide 2013 A5_AW.indd 12 30/08/2013 09:34