Glossary of Terms

We use industry terminology across this website. Whilst the terminology is widely known throughout the framing industry, we appreciate some terms may be unknown to some of our customers. To help we've listed our commonly used terms and their definitions below.


Acidic Browning (Ageing) - Mountboards and Backing Board are commonly produced from wood pulp fibre that have naturally occurring acids and lignins in them. Overtime these acids and lignins may cause the paper to brown. Dependent on their conversation grade, many mountboard and backing boards are chemically treated to remove lignins and neautralise acids. White Core, Conservation, and Museum grade boards are those grades which are chemically treated. The same acidic browning principles apply to other picture framing supplies such as Tape and paper products.

Acid-neutral / ph-neutral - The ph scale from 0 to 14 is used to measure the acidity of a material. 0 is highly acidic and 14 is highly alkaline. The wood commonly used to produce Mountboard,Backing Board, Pulp Board, and other paper products is naturally acidic or may contain lignin. Certain grade papers such as Cream Core still have this acidity present. Other grades, such as Conservation, have their acidity neaturalised.

Aluminium Moulding - Metal frames made from aluminium that are finished with a variety of colours and surface treatment. An advantage of Aluminium Frame Moulding is that it can be stored without fear of warping and that it provides a modern, clinical finish to the framed piece. An Aluminium Mitre Saw is used to cut the moulding to size whilst Aluminium Assembly Kits are needed to join the moulding.

AluWood - Aluminium moulding wrapped in a real wood veneer. AluWood is ideal for commerical interiors and contemporary styles and does not warp, twist, nor bow. 

Aperture (Mount Window) - The size of the beveled hole cut into a piece of mountboard for the artwork to be displayed through a 'window'. A Mountcutter is used to create an aperture. 

Ayous - Timber of choice for most Italian and Spanish moulding manufacturers. Pale in colour with close, indistinct grain, it is economical and takes base finishes and colour well. It is easy to cut and join. Triplochiton scleroxylon is a tropical tree native to West Africa; depending on where it is grown, it is also known as Obeche, Wawa, Samba and Abachi.


Backing Board - Encloses the back of a picture frame 'sandwich'. It is the final layer that seals the glass, mountboard and artwork together. Backing board can be held in place with a variety of methods such as fixing Framers Points then sealing the back of the frame with Backing Tape.

Backing Tapes - Generally brown paper tapes that are either Self Adhesive or Gummed. Applied to the back of the frame to create a seal between the picture frame and the frame Backing Board. This helps to protect the frame contents from dust, humidity, temperature fluctuations, and moisture. Backing tape is available in a variety of sizes, thicknesses, and adhesive properties.

Bevel - The 45° bevel that is cut into the picture Mountboard. The colour of the board exposed by the bevel will differ depending on the mountboard in use. 

Bradawl - A tool commonly found in woodworking with many framing workshop uses. Used for making an indentation in wood to ease the insertion of screws and nails. Picture framers mainly use a Bradawl on the rear of the frame to assist insertion of hanging equipment such as D Rings, Screw Eyes, Picture Hooks, Nails, or other Hanging Hardware.

Burnishing Tools - Used for smoothing rough edges of paper surfaces, usually as a results of a blunted blade or condition of the mountboard. Burnishing tools are available in mainly forms such as the traditional Burnishing Bone.


Canvas - Has had a use in picture framing for many years. In more recent times artwork has been printed directly to a canvas which is stretched in a drum-like fashion, Stretcher Bars and Brace Bars are some of the Canvas Materials needed for this function.

Canvas Frames - Tray Frames are usually the most suitable frame for a stretched canvas. Different finished and functions can be achieved by varying the depth of the picture frame moulding rebate. Canvas Hardware is needed to frame a stretched canvas.

Cutting Mat - A movable surface that is used to cut various materials such as mountboard. Cutting mats protect the framing work bench and also the blades in use.

Chop Service - We provide a popular service of chopping your wood and aluminium picture frame mouldings to your bespoke sizes. The Lion Chop Service saves the hassle and expense of mitring the moulding yourself as there is no wastage to allow for, nor any mitre machinery needed.

Clip Frames - Frameless picture frames that consist of glazing, mountboard, artwork, mount backing board, and frame backing board. This sandwich of materials is held in place with Clips around the edges.

Conservation Framing - The FATG (Fine Art Trade Guild) sets requirements for picture framers wanting to produce work at conservation level. Conservation level framing involves best framing practices that help achieve a high level of protection for the framed artwork or objects. In ideal conditions this level of framing should be good for 20 years, however this is dependent on the environment of where the framed piece is hung. Visit the FATG website for further information.


D Ring - A versatile and popular choice among framers, D Rings vary in size, finish, and use. Screw this small piece of framing hardware into the back of a frame (as a pair) and attached Cord or Wire. D Rings are the most common way to hang a picture frame as they offer a more robust hanging solution than a simple nail.

Double Mount - The common method of using two Mounts in a frame. Used as a way of enhancing the artwork, the inner and outer mount board usually differs in colour. This aesthetically pleasing practice draws the eye into the artwork and compliments the Frame Moulding.

Dry Mounting - Permanently sticking down the artwork to a sheet of self adhesive paper, Mountboard, or Foam Board. This method avoids the use of wet adhesive which can become messy if not used correctly. Dry mounting is a useful way of flattening a print or photograph. Air bubbles can form across the artwork if the dry mount isn't applied uniformly, care is advised. A hot press machine is used for apply Hot Mounting Film, alternative Cold Mounting Film can be used.


Embossing - The process of making small indented patterns. To achieve this effect an Embossing Tool is needed, this is similar to Bradawl but with a balled/rounded head. Press the embossing tool into the material and draw to create subtle embossed lines or indentations. Embossing is used primarily for decoration as it adds visual depth towards the framed artwork.


Fillets / Slips - This term is used when referring to a small piece of frame moulding, used for inside the rebate of the frame or between the picture mountboard and artwork. Filltets are primarily decorative as they provide a clean line and also add depth between the artwork and the glass.

Finger Jointed Pine - Pine is cut into shorter lengths to remove knots. Interlocking ‘fingers’ at each end are routed out and glued together. This gives base timber for moulding that is knot free, straight and economical. Finger Jointed Pine will become more popular as a base timber due its availability, price and sustainability.

Foam Centre Board / Foamboard Foam Board is a versatile material that is widely used in the framing industry. Uses include mounting artwork for display purposes and acting as a barrier board between the artwork and frame Backing Board. Foam board is available in a variety of thicknesses and can come with a self adhesive backing. 

Foil - Hot foil stamping is a process developed in the 1930s as a substitute for traditional gilding, although foils are now available with many other effects including wood grain. The decoration is printed by on a polyester film treated with a release agent and a protective varnish. The decoration can be subsequently metalized and finally the thermo-adhesive is applied. Foil is applied using heated rollers to a moulding previously finished with trafila or gesso. Foils can be applied in combination or to one part of the moulding only, such as the sight edge.

Framer's Tabs / Points - Sharp, flat pieces of metal that are fired into the side of frame moulding rebate to hold the backing board in place. Points come in a variety of shapes and are also available in flexible or semi-rigid finish.

FSC - Forest Stewardship Council TM is an independent, non-governmental, not for profit organisation established to promote the responsible management of the world's forests.


Gesso – Also known as compo or clay. Forms a smooth surface over wood grain using a combination paint mixed with chalk and pigments, ready to finishing. Fine layers of gesso are used by manufacturers in the Naples area of Italy as a base for gilded and foiled mouldings. In the Far East, thicker layers of gesso are often used as a base for all finishes. Mouldings with thicker layers of gesso tend to cut better on a saw.

Gilding - The application of gold leaf, paint, or wax to a picture frame to give the appearance of a continuous layer of gold. A large range of Gilding materials is stocked.

Glass Cutter - The go to tool for picture framers wanting to cut glass by hand. Use a Straight Edge to run the Glass Cutter along to guide the incision into the glass.

Glazing (Glass) - Glass or acrylic glass sits in front of the mountboard, artwork and backing board. Glazing protects the framed artwork or object from dust, humidity, moisture, and temperature fluctuations.


Hangers - There is a huge variety of methods available to picture framers when hanging a picture or mirror. The selection of Hanging Hardware depends on application, weight, personal preference, and hanging environment. Such picture hangers include D Rings, Screw Eyes, CWH Hangers, Panel Hanging Plates, Heavy Duty Hangers, Lightweight Hangers, Security Hangers, Cord, Wire, Picture Hooks, Self Fix, and Hanging Plates.

Hardwood - Many of the woods used in Picture Frame Moulding are the softer or medium hardness variety. However, some woods such as Oak are class as hardwoods which as dense and can be more problematic to work with, i.e. harder to cut on a Morso. Hardwoods are still very workable but require the correct skill, technique, and materials.


No entries


No entries


No entries


Lacquer - Seals and protects the finish, and can add a matt, satin or gloss finish.

Leaf - Very thin gold or silver coloured metal applied onto a smooth gesso base, either mechanically or by hand. It is usually either finished with a patina or distressed to show the base, and then lacquered.

L Style - A moulding designed to frame a stretched canvas or panel, as opposed to a traditional glass and image package. The canvas sits inside the ‘L’ rather than underneath the lip of the rebate.


MDF - Medium Density Fibreboard has many uses in the framing industry, most commonly as Backing Board. MDF is relatively inexpensive but may be prone to warping if not stored under the correct conditions.

Mitre Guillotine - Picture Frame Mouldings must be accurately and precisely cut to size at 45° angles, referred to as mitres. The most precise and popular method of mitring is to use a Mitre Guillotine which can be foot operated or power operated, depending on production volumes.

Mitre Joint - In order to make a picture frame, the moulding needs to be cut into accurate lengths. Cuts at 45° angles are joined together using Frame Joining Adhesive and an Underpinner firing V Nails.

Mitre Saw - Cut at various angles using a Mitre Saw. Aluminium frame moulding can only be cut on certain mitre saws.

Mouldings - Picture Frame Mouldings as lengths of material (wood, aluminium, or polymer) used to make the picture frame. Mouldings are stocked in a huge variety of sizes, colours, finishes, materials, and styles. They are usually supplied in 3m lengths and can be mitred in a framing workshop or cut to size using the Chop Service.

Mountboard - Wood pulp or cotton based boards that are cut to size with a Mountcutter. Mount Boards are graded using FATG standards, these are Cream Core, White Core, Conservation, and Museum.

Mountcutter / Mount Cutter - A tool that should be present in any framing workshop. A Mount Cutter cuts a straight or 45° bevel in the mountboard, used for cutting a sheet of mountboard to size to mount the artwork. Mount cutters vary in size and function to suit every framers needed, for mass production a workbench mounted machine is recommended, for small production and hobby framers a hand held mountcutter may suffice.


No entries


Offsets - Canvas Offsets are S shaped steel clips that fit a stretched canvas to a frame moulding. Screw one end to the back of the stretched canvas and the other to the reverse of the frame moulding.

Oval Mount Cutter - Specialised machinery is needed for cutting an oval aperture into a mountboard, many of which are computer programmable to cut a variety of shapes and sizes.


Paint - Over a trafila base give a smooth, opaque finish, while on open grain it is often applied in layers to given different effects.

Patina - A generic term used to refer to a wide range of finishes added to the surface of a moulding. This can include brushing on finely ground pigment to give an aged effect and applying a pale wash or a wax over a base colour.

Plexiglass - A trading name for plastic/acrylic Glazing, an alternative to glass glazing. Acrylic is shatter resistant so is much less likely to break whilst in transit and is a safe alternative for certain environments where safety is key, such as schools, hospitals and public buildings.


No entries


Ragboard - A term used to describe a 100% cotton based mountboard. Rag Board is usually conservation or museum grade due to it's natural ph neutrality. This is the preferred material for framers wanting to reach a conservation or museum grade standard.

Rebate - Mouldings have a lip to hold the glass and image package in place. From the lip to the base is known as the rebate. Some mouldings are made with a deep rebate to accommodate spacers when framing objects.


Shadow Box Profile - This is Picture Frame Mouldings that have a deep rebate and therefore are ideal for framing three dimensional objects. Such objects include sports shirts, memorabilia, and sports objects such as golf balls, cricket bats, etc. A Tray Profile or Deep Rebate frame moulding is the ideal choice for such a job.

Slips / Fillets - Narrow, shallow ‘mini mouldings’, used either in combination with the moulding or underneath a mount. Aesthetically, they add a space between the frame or mount and the image, while practically they create a space between the image and the glass. Slips are also known as fillets.

Softwood - Refers to the density of the Picture Frame Moulding. A softwood is malleable and easy to cut with a Mitre Guillotine.

Spacer - A strip of wood that fits inside the rebate, under the glass, Spacers are used to create space to accommodate an object, textile or thicker artwork.

Stain - Adds a colour while leaving the wood grain visible. The grain may be open or closed.

Straight Edge - The inner edge of a moulding, sometimes highlighted with a gold or silver foil. See the range of Straight Edges.

Stretcher Bars - Are used to stretch a canvas print. The slightly sloping edge of stretcher bars ensures the canvas onto comes into contact with the outer edge, this helps prevent the tearing of the canvas print. Stretcher Bars are available in a variety of sizes and finishes, Brace Bars are needed for bars over 762mm in length.


Trafila - Closes the wood grain by applying fine layers of a thickened lacquer base, for a smooth surface ready to be finished with lacquer or foil. The moulding passes through the trafila template, forcing the lacquer into the grain. Typical of mouldings made in the Tuscany region of Italy. Trafila finishes cut well on a Morso because the fine layers do not chip.

Turnbuttons - Flat pieces of steel that are screwed into the back of picture frames to hold the backing board in place. They are ideal for when artwork needs to be removed and replaced. Turnbuttons come in a variety of finishes to compliment the picture frame.


Veneer - Very thin slices of wood, applied to a base timber. Besides giving the effect of an expensive wood at a much lower cost, veneers also offer the look of a hard wood such as Oak, but on an easy to work base timber, such as Pine.

V Nails (Wedges) - V shaped pieces of steel that are fired from an Underpinner to join Frame Moulding Lengths. A small amount of Frame Joining Adhesive is applied to the end of moulding lengths to make the ends rigid. Two lengths are then slid into the underpinner and joined with multiple V Nails. Care should be taken to ensure the V Nails are the correct sizes for the moulding being joined, if they are too long they may break the moulding surface and protrude out of the moulding face.


Wood Glue - A suitable adhesive should be used in conjunction with V Nails to ensure a robust join of frame moulding lengths. A popular Frame Joining Adhesive is a PVA based wood glue.

Working Loads - We test much of our stock Frame Hanging Hardware with a purpose build load testing rig. Two icons are used to show working loads, the black one is a load figure that is untested and based on experience and best judgement. The other icon, black with a red dot, indicates the SWL (safe working load) that is tested in on our rig. Typically the figure displayed is 25% and 33% of the load at failure.


No entries


No entries


Z Bar Hangers - Aluminium profiles that interlock to provide a stable and level means of hanging pictures and mirrors. Z Bars are a popular choice among trade installers and display contractors due to the ease in which hanged art can be swapped.