Upload
sandytree
View
21
Download
0
Embed Size (px)
Citation preview
Adhesives, Mechanical Fixings, Sawing Drilling and Sanding
A Brief Guide To S<cking, Cu?ng, Drilling and Sanding Stuff
Adhesives
• Superglue / cyanoacrylate • Epoxy resin • UHU • Plas<c Weld / Dichloromethane • Tensol 12 and 70 • Contact Adhesive • Spray Mount
Adhesive guidelines
• Not all adhesives are suitable for all materials • Some adhesives come in 2 parts • Some adhesives will require PPE • Spray mount should be used in a spray booth • Some specialist adhesives use UV light to cure • Although adhesives can be looked on as unreliable, modern technology has improved them.
Superglue
• Low viscosity • Bonds a wide range of materials • Rela<vely easy to use • Easily bonds skin! • Large quan<<es can create fumes • Can be fragile, especially when cold • Can dissolve some foam materials
PVA (wood glue)
• Used usually for woods and cards • Can be used for other wood based
products such as MDF and cork • Safe to use with foams • Cheap • Easy to clean up excess • Strong • Long cure <me • Best used in conjunc<on with clamps
during cure <me • Not suitable for non porous material such
as plas<cs
Epoxy Resin
• Two part adhesive • Strong bond strength • Come in variety of strengths and cure <mes • Some<mes come in syringe or tubes • Can react with some foam materials • Usually cures clear • Can be stringy when in use • Care must be taken when using it
UHU
• Strong bond strength • Good for cards, papers and some woods • Stringy when used, care needed! • Cure <me can be long • Difficult to wipe off excess • Cheap
Plas<c Weld
• Very low viscosity (water like) • Ideal for bonding plas<cs • Use by applying with brush • Care must be used • Cheap • Can produce gas bubbles when curing • Fast cure <me
Tensol 12 and 70
• Extremely high bond strength • Thick consistency • Clear in appearance • Tensol 70 is 2 part with low gassing proper<es • Both types thought to have carcinogenic proper<es • Bond plas<cs only • PPE must be used • Must be used in well ven<lated areas
Contact Adhesive
• Thick consistency • Stringy when used, care needed • Very strong bond • Instant grab, posi<oning needs to be right first <me • Use in well ven<lated areas • Use appropriate PPE • Not suitable for foams • Will bond a wide range of materials
Spray Mount
• Ideal for cards and papers • Easy to apply on to material • Can be expensive • Medium bond strength • Difficult to apply in small, concentrated areas • Must be used in well ven<lated areas (spray booth) • Instant grab • Fast cure <me • Unsuitable for foam
Mechanical Fixings
• Which fixing is best can alter widely depending on material and purpose
• Thought needs to be given to how many fixings, how far apart and what materials are being fixed together
• Some fixings are more permanent
Screws
• Usually used for wood • Can vary in material type; -‐ BZP, brass, black japaned, stainless steel • Head/drive can be different; -‐ Pozi-‐drive, Phillips, Slot, Torx, Security fi?ngs • Various widths and lengths
Nuts and Bolts • Similar to woodscrews but finer thread • Many different thread pitches, imperial types include UNF, UNC, BA, Whitworth, BSF, metric types include fine and corse pitches • Material can vary, brass, s/s, BZP • Different head types and drives • Countersunk • Buaon head • Cheesehead • Hex head • Torx drive • Security fi?ng • Allen bolt • Grub screws • Machine screws have either pozi-‐drive, slot or phillips drive
Rivets
• Two sheets of material are drilled with a hole the same diameter as the rivet’s shank • The two sheets are pressed together and the rivet passed through the hole • The rivet is then pressed, hammered or squashed between a dolly and a hammer to
squash the shank so that it cannot pass back through the hole • Rivets can be used hot or cold • Old technique, not usually used these days
‘Pop’ Rivets
• Two sheets of material are drilled with a hole the same diameter as the wider part of the rivet
• The rivet is pushed into the hole • A rivet gun is used on the thinner end • The rivet gun pulls the thin stem which is connected to the wider end internally • As the gun pulls the stem, it squashes the wider part, trapping the sheets between it and the head of the rivet • More popular than tradi<onal rivets
Pins and Nails
• Used to fix woods together • Different material types • Heads can be flat or domed • Different lengths • Some<mes a pilot hole can be used • Some<mes used with glues
Sawing
• Sawing materials can be done using a wide range of hand, power and machine saws
• Blades can be circular, bands, flat or reciproca<ng
• Different blade types for different materials • Saws need to be used with great care
Hand saws
• Wood/carpenters saw • Tenon saw • Piercing/coping saws
• Also (not shown) are; • Hacksaws • Junior Hacksaws • Micro saws • Masonary saws
Bandsaws
• Con<nuous blade in a band • Can be used to cut wide range of materials • Ogen used for speed and accuracy • Extrac<on is needed when in use • Goggles and ear defenders needed in machine shop • Various sizes and power ra<ngs
Drilling
• Many different methods of drilling a hole • Many different types of drill bit • Speeds need to be checked • Some drill bits aren’t suitable for some materials
• Some drill bits can be used in powered equipment, others cannot
Cordless drills
• Baaery powered • Keyless chuck system • Choice of speeds • Hammer ac<on • Torque se?ngs • Variable speed on trigger • Direc<on of chuck is reversible
Pillar drills
• 4 Main parts; Head, Pillar, Bed/Table and Foot • Variable speeds • Depth gauge • Moveable bed/table • Higher power than cordless drills • Usually perpendicular • Use in conjunc<on with drill vices
Drill Bit Types
Twist bit, Auger, High Helix metal bit, SDS bit, Spade bit, Masonary bit, TiN coated twist bit, HSS twist bit, another spade bit, Step drill and countersink bit
Forstener Bits
• Used in either cordless or pillar drills
• Only for woods • Used for larger (20mm+) size
holes • Creates flat boaomed blind
holes
Hole Saws
• Used for larger holes • Not for drilling blind holes • Used in conjunc<on with
mandrel • Not suitable for drilling deep
holes • Poor swarf clearence • Used only for woods
Sacrificial Boards
• Sacrificial boards are used when drilling clean holes in materials
• Used to avoid drilling bed of the machine or table
• Support material as drill bit breaks through, avoiding ‘breakout’
• Par<cularly useful when drilling acrylic and other briale materials
Drill Vices
• Used when drilling smaller pieces of materials
• Safer to use than holding materials by hand
• Come in many different types and sizes
Sanding Methods
• Different types of sanding from paper to power tools to machines
• Can be used to achieve beaer finish on material, provide a key or to remove imperfec<ons prior to spraying
Sand paper
• Different grades and types available • Come in sheet, roll and pad form • Can be held by hand but; • Best stuck to a board to create a sanding s<ck • Used on a wide range of materials
Wet and Dry Paper
• Used for achieving higher surface finish quality
• Grades between 200 – 2500 grit paper • Used with water to avoid clogging • Used usually with plas<cs for a polished edge finish • Some<mes used on varnished or lacquered woods between coats
Sanding sponges
• Used by hand • Creates smooth finish over curved
surfaces • Available in different grits • Wear out quickly • Not suitable for achieving sharp
edges • Used on woods and plas<cs
Linishers
• Powered machine • Care needed when using • Used with woods and plas<cs • Extrac<on needed • PPE (goggles and ear defenders needed) • Removes material very quickly • Different grit belts and pads
Disc Sander
• Powered machine • Extrac<on needed • PPE (goggles and ear defenders
needed) • Removes material quickly • Only use the ‘down’ side • Different grits available • Beds can be angled • Protractors available for mitres