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http://www.youtube.com/watch?v=M-F-7uApykM
1ALAN MASON
Diploma level 1Know how to produce
components from moulds.Unit no CC1013K
2ALAN MASON
• Aim(s) of the lesson• For students to successfully complete unit CC1013K • Know how to produce components from moulds.
• Learning objectives• All students will be able to identify different types of
fibrous tools.• Students will be able to recognise and name associated
trade tools required for making flood moulds.• All students will have an understanding of different
materials associated with fibrous plastering.• Students will take part in a discussion regarding health
& safety
ALAN MASON 3
Fibrous Work• Fibrous plasterwork is the ornamental,
decorative side of plastering• The tools you will be using are very different of
those used in traditional plastering• The plaster used is pure gypsum• Fibrous plasterwork is made in workshops and
transported to site• You will need the ability to imagine work in
reverse• Maths and geometry skills and the ability to
measure accurately• Fibrous work requires patience and delicate
handsALAN MASON 4
Basic operations
• Moulding process – forming of a reverse shape of an item in solid or flexible material
• Casting – producing the finished product from a mould
• Casts – can be produced both in casting plaster (hemi-hydrate class A ) and sand and cement (ordinary Portland) from flood moulds.
ALAN MASON 5
Tools required for fibrous plasterwork
Joint rule
Splash brush Busk Small tool 6ALAN MASON
bowl for bench work Scissors
Tools required for fibrous plasterwork
7ALAN MASON
Joint rule
Scissors
bowl for bench work
Splash brush BuskSmall tool
Tools for making running mouldsCoping sawSurform/Rasp FilesWood chisel Tin Snips Square Panel or cross pein hammerClaw hammerTenon SawDrawing Compass,
8ALAN MASON
Tools for making running mouldsCoping sawSurform/Rasp FilesWood chisel Tin Snips Square Panel or cross pein hammerClaw hammerTenon SawDrawing Compass,
9ALAN MASON
Equipment for casting mouldings• Fibrous plasterwork
needs a range of different items of equipment.
• Buckets• Bowls
ALAN MASON 10
These should be made of heavy duty plastic because they will take a lot ofwear. Used for mixing larger amounts of plaster, carrying water and rubbish.
These are usually made from plastic or rubber, for easy cleaning after use.They are used for mixing up small quantities of plaster and for holding water.
Fibrous Bench• Benches• These should be made to last,
with a strong timber frame, usually about 3m long and 1m wide, and will have a topping of plaster, which makes it easier to repair holes and damage to the face of the bench,
• Some benches are covered with hard-wearing laminate (like a kitchen worktop)
• The bench must have a true, straight running rule of timber or metal on each side for running out mouldings.
ALAN MASON 11
ALAN MASON 12
Plaster used for fibrous workThis is called casting plaster the correct name is
Hemi – hydrate plaster (Class A as specified in BS 1191)
During manufacture three quarters of the water is driven off using heat.
When mixing the water is added back into the natural gypsum and is cast as you wish into a mould.
Dextrene: when made into a solution and added to the water in which plaster/render (cement casting) is to be mixed it will both harden and retard.
ALAN MASON 13
Why does casting plaster become warm?
• As the plaster sets it becomes warm therefore making a chemical reaction
• This releases the heat generated during manufacture, the plaster then cools and then sets
• Casting plaster is manufactured at different strengths according to the work carried out.
• The hardness of plasters can be found in the manufacturers information
ALAN MASON 14
Fine casting plaster is used for most casting needs, running mouldings and producing plaster casts. It is also the plaster that is used in fixing and mitring.It is the most used of all fibrous plasters.
• Fine Casting plaster is probably the most common general purpose plaster. It is a "beta" plaster versatile and economical its used in numerous industries. It is light in weight and easily carved once set.. Plaster/water ratio: 1.3kg/Litre.
•Bag size 25Kg.
• Price: £6.73
ALAN MASON 15
• Fine Plus Casting Plaster is a general purpose beta plaster that has better working characteristics than fine casting. Plaster/water ratio: 1.3kg/Litre.
Made in the UKBag size:- 25Kg.
• Price: £7.06
ALAN MASON 16
•Super fine plaster is a much finer material and is used for detail work, i.e.•mouldings, etc. that have delicate shapes and lines. It is also used with fine plaster when casting. •For example, the face of the cast would be in super fine (‘firstings’), and then the fine would be used to back up the casts (‘seconds’).
Crystacast Plaster is a "top of the range" product by nature of its extreme hardness and density. Used
anywhere that high surface harness is needed.• Fibrous plasters also come in
degrees of strength. • For example, if you are
producing mouldings that are liable to get damaged, you want a good hard plaster.
• Similarly, if you have a cast that may need a bit of work to get it out of the mould, then a slightly harder plaster is needed.
• A reverse mould that will have a lot of casts taken from it may need a hard face, so again it is sensible to choose a harder grade of plaster.
• Manufacturer’s technical literature will provide information on the hardness of plasters
ALAN MASON 17
Plaster/water ratio: 3.57kg/litre
Pack size:- 25kg.Price: £17.82
Rugby Portland• The original "general
purpose" product, Rugby Portland is used in various applications, for concrete, mortar and render.
• It is consistent in quality and performance.
• For general use in concrete, mortar, render or screeds
• Compatible with lime and plasticising admixtures
ALAN MASON 18
Questions• Q. Casting plaster is applied to flood moulds using a :• A. • Q. What type of cement is used for casting from flood moulds is: • A. • Q. Casting is also called a:• A. • Q. Small tools can be used to:• A. • Q. Dextrene is used as:• A.• Q. What is on each side of a casting bench:• A. • Q. Manufacturer’s technical literature will provide information on
the ..................... of plasters.
ALAN MASON 19
Questions• Q. Casting plaster is applied to flood moulds using a :• A. Splash brush• Q. What type of cement is used for casting from flood moulds: • A. Ordinary Portland • Q. Casting is also called a:• A. Class A plaster • Q. Small tools can be used to:• A. CLEAN UP CASTS• Q. Dextrene is used as:• A. A hardener• Q. What is on each side of a casting bench:• A. Straight running rule of timber.• Q. Manufacturer’s technical literature will provide information on
the ..................... of plasters.
ALAN MASON 20
HARDNESS
Hessian/canvas• Jute Scrim
The narrowest of the woven jute products ideal for panel mouldings etc as well as general plastering…
• Canvas 6" (15cm)Canvas, 6 inch/150cm wide Jute open weave. Roll length:- 200mtrs…
• Canvas 12" (30cm)Canvas, jute open weave. 12"/30cm wide. Roll length:- 200mtr…
• Canvas 18" (50cm)Canvas, 18 inch/50cm wide Jute open weave. Roll length:- 200mtrs.…
ALAN MASON 21
ALAN MASON 22
Reinforcement
• Plasterers Jute Scrim for use in construction of Ornate Plaster ware to help prevent cracking out, may also be used to reinforce plaster based mould support cases. Available in several widths 3 inch (75mm), 6 inch (150mm) , 12 inch (300mm) and 36 inch (900mm) nominal sizes. Hessian. Canvas. Jute
ALAN MASON 23
Methylated Spirit /Shellac Flakes
• Shellac Flakes• Shellac Flakes are
dissolved in industrial alcohol or good quality methylated spirit to make up shellac sealer. Starting point formula is 350gm per litre of spirit.
• Metylated Spirit 5ltr• Methylated Spirit used
for thinning shellac
ALAN MASON 24
Shellac flakes• Shellac is a painter’s knotting or button polish• Plasterers mix it with meths to thin it down• Shellac is an all-natural resin secreted by the female
lac bug to form a cocoon, on trees in the forests of India and Thailand
• Shellac is used to seal the surface of the mould and prevents water from other coats been dried out
• Apply 3 thin coats to the plaster surface to give a polish
• Shellac is also used on bench surfaces
ALAN MASON 25
Lac (Laccifer Lacca) are scale insects (insects that attach themselves in great numbers to plants and trees) which drain
the sap from the bark of their host tree, allowing them to secrete lac resin which is scraped off and manufactured into
shellac. Around 300,000 insects are used to produce 1kg of lac resin
ALAN MASON 26
Size• Because casting plaster has a setting time of about 15
minutes, for most casting jobs it would be too quick, so to slow it down we use size.
• Traditionally plasterers use painter’s glue size that is put into water to dissolve with a handful of lime.
• The lime is to stop the glue size becoming too stiff, because size needs to be in a liquid form.
• The liquid material is boiled in a bucket, allowed to cool and then tested for strength to see how long it will stop the plaster from setting.
• Glue size is used in casting as a retarder.
ALAN MASON 27
Alum
• This is an accelerator used in casting.
• Why do you think you would use this?
ALAN MASON 28
Grease/release agent/Raw Linseed Oil• Raw Linseed Oil• Raw Linseed Oil 500ml
Bottle. Has many uses and works well as a releasing agent on fibreglass or sealed plaster moulds.
• (Tallow)Used to prevent the plaster from sticking to the bench, and also helps with the running of the mould along the bench.
• Made from animal Fat
ALAN MASON 29
Grease or release agent• Traditionally made up of tallow (form of animal
fat) mixed with cheap engine oil or meths. The ingredients are melted together and allowed to cool. This is applied by brush to grease up moulds and helps to release the cast.
• Neat tallow can be used when working with difficult reverse moulds
• Tallow is used when mould running on the bench to allow easy movement MOULDS
• Raw Linseed Oil is also applied to reverse moulds to help remove casts
ALAN MASON 30
Laths• These are thin strips of sawn,
rough timber that are usually about 3 m long and as straight as possible.
• They are 3 mm thick and 25 mm wide, and are used for reinforcement and for fixing the casts.
• Because they are likely to be very dry, they are best kept soaked in a long water trough to stop the water from the plaster being sucked out and also to stop the laths from twisting when they become wet.
• This movement could twist the cast and lead to possible cracking of the face.
• Bearers in moulds are made from (wood) lath.
ALAN MASON 31
2ND SET of Questions• Q. What is the reinforcement is used in plaster casts:• A. • Q. What is canvas made of:• A. • Q. What material is used for thinning shellac:• A.• Q. What is the name of the bug from which shellac is produced:• A. • Q. Glue size is used in casting as a:• A. • Q. Alum is used in casting as:• A. • Q. What is raw linseed oil used as:• A. • Q. What will tallow prevent and what is it made of:• A. • Q. Bearers in moulds are made from ............ lath.
ALAN MASON 32
2ND SET Questions• Q. What is the reinforcement is used in plaster casts:• A. Canvas (hessian)• Q. What is canvas made of:• A. Fibre• Q. What material is used for thinning shellac:• A. Metylated Spirit• Q. What is the name of the bug from which shellac is produced:• A. Lac bug (Laccifer Lacca)• Q. Glue size is used in casting as a:• A. Retarder.• Q. Alum is used in casting as:• A. An accelerator • Q. What is raw linseed oil used as:• A. releasing agent (allowing casts to be removed)• Q. What will tallow prevent and what is it made of:• A. Plaster sticking to the bench/ animal Fat • Q. Bearers in moulds are made from ............ lath.
ALAN MASON 33
WOOD
RUBBER MOULDS
• http://www.youtube.com/watch?v=MJ9lgZ3V90o
ALAN MASON 34
Material for moulding techniques• Re-meltable Vinyl Mould
Rubber, often known as Vinamold or Gelflex .
• This material is used where the mould is not required for long service and so can be reused many times.
• It's main disadvantages are:- The pattern or "plug" that is to be moulded has to be able to stand the temperature (130 oC) of the rubber. (porous objects tend to blow bubbles).
• Also it requires a temperature controlled melting pot
ALAN MASON 35
Remeltable Vinyl Rubber
Polyvinyl chloride (PVC)• This is a material made from vinyl resins known to
fibrous plasterers as ‘rubber’, and also called hot melt compound or HMC.
• It comes in different types of flexible grades, and each grade is a different colour to make it easier to see the difference.
• It is melted down in a machine at temperatures ranging from 120 to 170°C.
• The main problem with PVC is its high temperature, as this can affect some models: air may be released from a model which has not been fully sealed, and these air bubbles will form holes in the rubber that will produce bumps on the casts from the mould.
• There are two types of rubber moulding HOT & COLD
ALAN MASON 36
Advantages (HMC)
• Does not lose its flexibility• Less likely to tear• Can be remelted and reused• No mixing of different materials is required• Convenient for one off casts
ALAN MASON 37
Disadvantages (HMC)
• Expensive melting equipment is required• Materials are dangerous when hot extreme
temperatures• Toxic fumes• Your are not guaranteed a good standard of
pour every time
ALAN MASON 38
A mould being poured with cold pour
ALAN MASON 39
Cold pour moulding compound
• A Flexible silicone rubber.• Stored in sealed metal containers called blast
storage bin• Its shelf life is about 6 months• Cold pour consists of 2 chemical materials
that have to be weighed , measured and mixed. One is liquid form and acts as a catalyst so the correct hardening and setting process takes place
ALAN MASON 40
The advantages of cold pour are:• The mould does not lose its flexibility• The mould will not easily tear• No expensive equipment is needed and can be
used on site• Almost a perfect pour every time if the
preparation is done correctly• Will reproduce far better details from originals
than PVC• Many more casts can be made from cold pour
than PVC before it
ALAN MASON 41
The disadvantages of cold pour are:• Expensive to use because it cannot be cut up
and reused• You must be able to weigh the materials
accurately and measure out• Carefully to get the right mix• Requires special storage because they are
potentially dangerous chemicals.
ALAN MASON 42
ALAN MASON 43
Discussion of advantages and disadvantages
ALAN MASON 44
Making a flood mould• Flood moulds are flexible and ideal for small
repeated casts• One gauge casting is used when casting small
items.• They are made of material known as
rubber(vinyl resins)• They are also called hot melt compound or HMC• It comes in different grades and colours• It is melted down in temperatures of 120 to 170
degrees C
ALAN MASON 45
Method of taking a cast from a flood mould
• Set up you equipment and materials• Ensure your mould is clean otherwise this will
create imperfections on the cast.• Remember casting plaster sets within 15
minutes you need to be organised• Cut your canvas to size allowing an over lap to
turn inwards • Cut the laths to size and soak in a trough• Set up 2 buckets of water one for mixing, one
for washing out46ALAN MASON
Firstings
• Put clean water into a mixing bowl• Add the casting plaster let a few handful just soak in
the mix with you hands• Using a splash brush apply a thin coat painted to the
surface of the mould• Next splash the plaster on again using the brush
covering any traces of the mould ensuring the face is covered
• This mix is called the FIRSTINGS• Clean the mould edge, never use sharp instruments
47ALAN MASON
SecondsThe firstings will become shiny, when first applied, then it
will become matt when it is beginning to setMix the Seconds apply a thin coat over the cast then put
on the canvas reinforcement lay on the laths and cover them with canvas also.
These laths are classed as bearers to support the cast and are made of wood.
The reinforcement in plaster casts is placed in the second coat.
Brush them over with casting plaster and ensure the laths and canvas are not proud of the mould. This allows the mould to sit flat on the surface it is to be mounted on.
48ALAN MASON
• Next splash on the remaining of the mix to cover the canvas and laths using the splash brush this gives an even and lighter cast
• When casting in plaster the two coats are named firstings and seconds
• Clean around the edges of the mould and leave to set.
• Clean your tools and area• Once set and the cast has become hot then
cold you can now release the cast from the flexible mould
49ALAN MASON
Skull
• A rubber mould can be made of this skull and used many times before being re-melted.
• Make the skull in our workshop.
• This flood mould is a small item and can be cast in one gauge.
50ALAN MASON
Cement casting• There are three methods for
casting in Portland cement: • 1 Pressed semi-dry casting method
in a rigid reverse piece mould.• 2 Wet casting method in a rigid
reverse piece mould.• 3 Wet casting method in a flexible
mould. • The advantage with the semi-dry
technique is, that it is far and away the fastest, as a cast takes 20 to 30 minutes.
• When a cement cast is consolidated this means, it has been made more dense.
• It is recommended to use ordinary Portland cement (OPC) for this purpose
Cast decorations in plaster, gypsum or cement on facades
51ALAN MASON
Cement casting Wet casting1. Making of a negative casting
flood mould in, rubber. 2. The most common type of flood
mould is open backed, only with decorations on the three sides - plus possibly top and bottom.
3. The casting mass, Portland Cement, is poured into the casting mould. Steel reinforcement and Irons or other systems for mounting are fastened in the wet and soft material.
4 . A wet cast demands a day in the mould to harden.
5. After the hardening the cast element is removed carefully from the casting mould and at this stage, Cement casts are cured by immersion in water.
Wet casting with Portland Cement in flexible reverse moulds:
3RD Set of Questions• Q. The reinforcement in plaster casts is placed in which section of the
procedure:• A. • Q. What are the names of the two coats of plaster when casting: • A. • Q. The laths, classed as bearers to support the cast and are made of:• A. • Q. There are two types of material used for flood moulds:• A. • Q. Flood moulds are used because they are:• A. • Q. Flood moulds are used to cast: • A. • Q. One gauge casting means:• A.
ALAN MASON 53
3RD Set of Questions• Q. The reinforcement in plaster casts is placed in which section of the
procedure:• A. The second coat. • Q. What are the names of the two coats of plaster when casting: • A. Firstings and seconds• Q. The laths, classed as bearers to support the cast and are made of:• A. Wood.• Q. There are two types of material used for flood moulds:• A. Hot and cold moulding material.• Q. Flood moulds are used because they are:• A. Flexible• Q. Flood moulds are used to cast: • A. Small repeat items• Q. One gauge casting means:• A. Casting small items.
ALAN MASON 54
Method of taking a cast from a mould• Set up your -------------------- and -----------------------• Ensure your mould is ----------------- otherwise this will
create imperfections on the ------------• Remember casting plaster sets within ------ minutes you
need to be organised• Cut your --------- to size allowing an over lap to turn inwards • Cut the ------------ to size and soak in a trough• Set up ----- buckets of water one for ---------, one for
washing out
• Equipment , 2, mixing, cast, materials, laths, 15, clean, canvas
55ALAN MASON
• Put clean water into a mixing bowl• Add the ----------- plaster let a few handfuls just
---------- in the mix with you hands• Using a --------- brush apply a thin coat painted to the
surface of the mould• Next splash the plaster on again using the ----------
covering any traces of the ---------- ensuring the face is covered
• This mix is called the -----------------. • Clean the mould edge, never use --------------
instruments
• Mould, casting, soak, brush, splash, sharp, Firstlings
56ALAN MASON
• The --------------------- will become shiny, when first applied, then it will become ------- when it is beginning to set
Mix the ----------- apply a thin coat over the --------- then put on the ------------ reinforcement lay on the laths and cover them with canvas also.
These laths are classed as bearers to support the cast and are made of wood.
The reinforcement in plaster casts is placed in the second coat.
Brush them over with casting ------------ and ensure the laths and canvas are not ------------of the mould. This allows the mould to sit ----------- on the surface it is to be mounted on.
Matt, flat, firstlings, seconds, canvas, plaster, cast, proud
57ALAN MASON
• Next splash on the remaining of the mix to cover the --------- and laths using the splash brush this gives an even and lighter cast
• Clean around the ---------of the mould and leave to set.
• Clean your --------- and --------• Once set and the cast has become ----- then
cold you can now ---------------- the cast from the ------------- mould
flexible, canvas, edges, release, hot ,area, tools
58ALAN MASON
ALAN MASON 59
http://www.teachers-direct.co.uk/resources/
quiz-busters/quiz-busters-game.aspx?game_id=21786
ALAN MASON 60
FINISH
ALAN MASON 61
Construction of running
mouldsALAN MASON 62
Construction of running moulds
• There are a variety of different ways of constructing running moulds, but we will look here at the method of constructing a simple panel mould for running straight and circular mouldings, and at the running mould required for forming a cornice reverse running mould.
• This method can be used for constructing most running moulds: only very small additions are required for other running moulds.
ALAN MASON 63
Template The template of the profile is made
from the zinc or steel sheet. The profile shape can be drawn on
paper and glued onto the zinc. Cut around the zinc by using a pair of
snips. Place the template into a vice and,
using files, file down to the profile line. Always check your lines and do not go
beyond them. When you have filed up, a good check
is to lay the profile onto an original drawing and make sure it matches.
When you have finished filing the shape, file off the burr at the back of the template and, using a piece of wet and dry paper or nail, remove all the file marks left on the metal.
If these file lines are not removed they will show on your finished moulding run.
ALAN MASON 64
Construction of running moulds
• Stock• This is made from timber, and
supports the soft zinc and stops it from bending during the running.
• Lay the profile onto the stock and draw around it with a pencil.
• Then redraw a pencil line following the template outline back about 5 mm.
• Then, using a saw and a coping saw, cut the wood out to this second line.
• The back edge of the stock should be splayed away; this can be done with a rasp.
• The splaying away stops the wood collecting the plaster or getting in front of the template.
ALAN MASON 65
Horse or slipper & Hand brace
• Horse or slipper• This is the same height as the stock
but 1½ times the length. • It supports the stock, which is fixed
to it at right angles with nails or a housing joint.
• This slipper will run along the running rule that is fixed to the bench.
• Hand brace• This is fixed to the horse and slipper
and helps to keep it firm. • Some larger running moulds need
two hand braces. • The furthest point away from the• slipper is called the ‘nib’, and if this
moves too much it will cause chattering.
• The mould will need to be braced against this movement because, the larger the moulding, the more swell there will be in the plaster upon setting.
ALAN MASON 66
Circular running moulds
• A circular running mould is used for forming circular mouldings.
• The construction of this mould is very similar to straight moulds.
• In fact, you only slightly change your straight running mould to produce one.
• All you need to do is take a piece of wood called a gig stick, slightly longer than the radius of the circle required, and nail it on top of the stock and hand brace.
• Another way of forming this type of mould is to use an extended stock.
• The gig stick or extended stock should reach from the slipper to beyond the turning point.
• On the underside of the gig stick or extended stock, a piece of metal (called the turning eye) should be fixed with a hole in it about the size of a 50 mm nail at the radius distance.
• This will allow the running mould to rotate. The gig stick should be in line with the template face.ALAN MASON 67
Wad – a piece of canvassoaked in plaster whichforms an extremelystrong fixing
Running out a simple panel mould The running out of this type of moulding is the same method as
for the running out of any moulding. It is only the size that changes.
1. First repair any damage and hollows in the bench by using casting plaster and a joint rule. The bench should be slightly wetted before making good. When the plaster has set and dried out, give the bench three coats of shellac.
2. Grease the bench well, including the running rule and running mould.
3. Mark with a pencil the length of moulding you need to run out on the running rule.
4. Along the run length, put a nail at the highest point of the template, in the bench.
This is to stop the moulding slipping off as it begins to swell. Use either a headless nail or one with a small head, over which should be a piece of clay in the shape of a pyramid to help with easy release of the plaster from the nail at the finish of the run.
ALAN MASON 68
5. Now you will need to mix up your plaster. The amount of plaster you need depends on the size of the moulding. Put clean water into a bowl and sprinkle plaster into the bowl until it is just below the surface of the water. Allow it to soak for a couple of minutes. Grease up your arms and hands using barrier cream and mix up the plaster making sure that there are no lumps.
6. At the bench, pour a small amount of plaster along the length of the run. Take your running mould and, with the template facing the direction you are going, stand in front of it at right angles to the bench.
With your left hand holding the nib and resting on the bench and your right handholding the hand brace, walk backwards pulling the running mould.
Your left hand will feed the plaster back into the running and will push it into the running rule. Your right hand does the pulling. Hold a bowl at the end of the run for catching the unused plaster.
This can now be used again and cuts down on waste.ALAN MASON 69
7.Repeat the process, adding more plaster each time, building up to match the profile.
It will be necessary to clean the running mould in between runs by using a small tool or an old piece of lath.
8. When the plaster becomes too old, re-mix another mix for finishing off. This mix needs to be a bit wetter.
9. Once you have reached a good quality of finish, clean down the bench with a joint rule and saw the plaster to the required length.
If the bench is well greased, the moulding can be slid across the bench, or use a gauging trowel to slide along the length of the moulding to release it from the bench.
The moulding can now be lifted on its edge to the storage area.
ALAN MASON 70
ALAN MASON 71
Running out a simple panel mould The running out of this type of ............... is the same method as
for the running out of any moulding. It is only the ..... that changes.
1. First repair any damage and hollows in the bench by using ............ ....... and a ........ .... . The bench should be slightly wetted before making good. When the plaster has set and dried out, give the bench three coats of ........... .
2. ............the bench well, including the running rule and running ........... .
3. Mark with a pencil the length of moulding you need to run out on the ............. ......
4. Along the run length, put a ...... at the highest point of the .............., in the bench.
This is to stop the moulding slipping off as it begins to ......... Use either a headless nail or one with a small head, over which should be a piece of ...... in the shape of a ............. to help with easy release of the plaster from the nail at the finish of the run.
ALAN MASON 72moulding size
casting plaster joint ruleshellac
Grease
mould
running rule
nailtemplateclay
pyramid
swell
5. Now you will need to mix up your plaster. The amount of plaster you need depends on the ....... of the moulding. Put clean water into a ........ and .............. plaster into the bowl until it is just below the ............. of the water. Allow it to soak for a couple of minutes. Grease up your arms and hands using ............ .......... and mix up the plaster making sure that there are no .......... .
6. At the bench, ........ a small amount of plaster along the length of the run. Take your .............. ........... and, with the ............... facing the direction you are going, stand in ........ of it at right ........... to the bench.
With your left hand holding the .... and resting on the bench and your right hand holding the hand .......... , walk backwards pulling the running mould.
Your left hand will ........ the plaster back into the running and will push it into the .............. ...... . Your right hand does the pulling. Hold a bowl at the end of the run for .............. the unused plaster.
This can now be used again and ....... down on .......... .
ALAN MASON 73bowl
sprinklesurface
barrier cream
lumpssize
pourrunning mould
template
front anglesnib
brace
feed
running rulecatchingcuts
waste
7.Repeat the process, adding more plaster each time, building up to match the .......... .
It will be necessary to ......... the running mould in between ........ by using a small tool or an old piece of lath.
8. When the plaster becomes too ..... , re-mix another mix for finishing off. This mix needs to be a bit ......... .
9. Once you have reached a good ........... of finish, ........ down the bench with a joint ..... .... and saw the plaster to the required .......... .
If the bench is well ........... , the moulding can be slid across the bench, or use a ............. trowel to slide along the length of the moulding to ........... it from the bench.
The moulding can now be lifted on its ....... to the ............. area.
ALAN MASON 74profile
cleanruns
oldwetter
quality
clean
joint rule
length greased
releaseedgestorage
gauging
ALAN MASON 75
The ornate centre piece base is formed
The semi-circular cornice section is run insitu
Making a reverse cornice running mould• The construction of
this running mould is the same as the panel mould described on previous slides.
• Note the difference in the template and the use of an additional brace for the cornice running mould.
ALAN MASON 76
Running mould for a reverse cornice mould
Back of stock splayed back
FINISH
ALAN MASON 77
ALAN MASON 78
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Internal mitre Running a reverse mould
The finished cast taken from the reverse mould.
ALAN MASON 82
The ceiling stripped back to the timber "split lathing"