HISTORIC IRONWORK REPAIRS IN TIMBER-FRAMED BUILDINGS.

 

Appendix 1.

 

Glossary - Historic Ironwork in Timber-framed buildings.

 

Term

Description

Aspect ratio

The ratio of length to section.

Bar

Long metal member of high aspect ratio, any cross-section except hollow (tube).

Beetle

coll. Old name for a wooden mallet. Head is often iron bound to prevent splitting.

Billet

A slab of iron from the furnace before it is rolled (wrought) into bars and sheets.

Binder

Hewett's term for a U-strap.

Blacksmiths joint

coll. Any joint that has been made, reinforced or repaired with ironwork from the forge.

Bolt

A metal fastener with a cylindrical plain shank and enlarged head. The other end may be slotted for a key or threaded for a nut.

Boss

(of metal) A thick, metal circular plate. Acts as a terminal for tie rods or bars.

Bracket

(of metal) A fastening that joins two members by their inner faces.

Broach

Roasting spit hence coll. Large spike or pointed rod.

Carriage bolt

A type of bolt with a round head but square shoulder to prevent rotation.

Carriage screw

A heavy duty square headed screw for fixing woodwork by self-tapping. Modern ones have hex heads.

Cast iron

Iron that is poured molten from the furnace into pre-designed moulds according to the component required.

Charcoal iron

Very pure wrought iron produced in charcoal fuelled furnaces before the C18th industrial revolution.

Clamp

Horizontal timber plate pegged or bolted to the frame to support an inserted floor or rafters.

Cleat

Victorian word for a short piece of wood or metal nailed on transversly to secure a joint (cf. cramp or staple).

Clenching (Clinching)

The turning back of a nail passed through thin section timbers to prevent pulling out. Clenched nails are sometines passed through roves in shipbuilding work etc.

Clout

A short, large headed, thick section nail designed for driving into hard timber.

Conversion

The fashioning of building timber from the raw material I.e converting the tree into structural timber.

Cotter(s)

A wedged iron key used in pairs to secure a stirrup with gibs..

Cramp(s)

Long thin section metal rods bent at both ends to form a staple holding joints in place when driven in (also called dogs).

Crook

The curved portion of an ironwork tie. Bent either in or across the plane of the arm.

Die

Round or square tool for cutting external threads on rod.

Die stock

Hand held tool for holding dies for cutting external threads on rods.

Dogs

Heavy metal staples used to hold joints in place, known from roman times. Also called joiner's dogs, iron dogs.

Draw rod

A rod threaded at both ends to draw two timbers together.

Draw tie

A tie made from a rod threaded at one end and forged to a plate and pierced at the other. Used to draw tie beams to wall plates.

Drawbar

A tapered metal rod used to test timber joints before final assembly.

Fishplate

Flat plates used in pairs to reinforce or repair joints by clamping on either side with bolts or nails, metal or wooden.

Fitting

Generic name for any unspecific type of added metalwork.

Flitch plate

(of metal) A plate inserted into a slot within a timber and bolted into position to effect a hidden joint or repair.

Forelock bolt

An iron pin with a peined head and a tip slotted to take a triangular key (forelock).

Gib(s)

A square bar with nibbed ends acting with cotters to secure a stirrup.

Gusset

A flat plate linking two or more timbers by nailing or glueing.

Hex nut

A nut with six bearing faces for the wrench. Indicates an intervention after the C19th.

Iron-sick

A C17th nautical expression meaning that the iron-work fixings have corroded so badly the joints are no longer sound.

Iron-smith

The C14th name for the blacksmith (someone who works black metal as opposed to white metals like tin).

Joiners dogs

Heavy metal staples used to hold timber to be worked in place during conversion.

King bolt

A wrought iron rod used in place of a king post.

Lag screw

American name for carriage screw. Originally used to secure wooden jackets to lag hot vessels or barrels with.

Machine screw

A metal fixing that is threaded with a constant helical screw the length of its shank to allow it to be inserted flush into an appropriately housed thread.

Mild steel

Alloy of carbon and iron discovered in 1856. Similar properties to wrought iron but prone to corrosion.

Nail

A short metal spike with a fashioned head at one end and a point at the other. Used to fix by hammering into timber. From the Anglo-saxon naeyl.

Neck

A section of bar that has been narrowed to receive a staple for fixing.

Nut

An internally threaded metal fixing for attaching to bolts. Can be square or hexagonal in form.

Pattress plate

The collective name for the terminal plates used in conjunction with tie-rods or bars. Can be any shape.

Peg

A wooden peg of tapering form, usually round tapering to a square shafted head. Used to fix timber joints into place.

Peining

Enlarging the end of a metal rod or bar to form a head by hammering hot or cold.

Pin

A wooden peg of constant circular diameter.

Plate

(of timber) A large worked timber comprising either the top or sole (base) of a wall.

Plate

(as strip) Of ironwork, a flat, wide, rigid sheet without bends; of various forms pierced or formed to take nails, bolts, spikes or staples.

Puddled iron

Wrought iron produced in mass production coal fuelled puddle furnaces where a lake of molten iron is stirred (puddled) with a rod. Late C18th onwards.

Rabbit

(of carpentry) A long thin incised slot in a timber to receive the edge of a board, modernly called a rebate.

Repair plate

A timber that is nailed or bolted to another failing timber along its length to reinforce it, may resemble a clamp but takes no vertical load.

Rivet

A metal fastening bar which is secured by passing through two or more sheets of material and peining over both ends.

Rod

Long metal bar of high aspect ratio, circular in section.

Rove

Square slotted washer to receive nails before nail is bent over, used in early shipbuilding.

RSJ

Rolled steel joist.

S-plate

A metal plate made in the shape of the letter S. Acts as a terminal for tie rods or bars.

Screw

A metal fixing carrying a tapered helical thread the length of its shank to allow it to be driven into a material to secure a fitting. See machine screw.

Shank

The portion of a bolt or screw between the head and the tip.

Shoulder

(of metal) A raised section of a metal fastening designed to house a staple and prevent pulling out.

Spike

A large nail, greater than 5 inches in length.

Square nut

The original form of nut with four bearing faces for the wrench.

Staple

A U-shaped metal fastening with pointed ends. Can be squared or rounded in form. Driven into woodto retain joints.

Stirrup

A U-shaped band with eyelets forged into the two ends to take gibs and cotters.

Strap

Any kind of thin section metalwork of high aspect ratio that has been used to make, reinforce or repair joints.

Strip

(as plate) Of ironwork, a flat, narrow, rigid sheet before being bent; of various forms pierced or formed to take nails, bolts, spikes or staples.

Tap

Spiral metal tool for cutting internal threads.

Tap wrench

Hand held tool for holding taps for cutting internal threads.

Tie rod(s)

Long metal rods that have fixings at both ends to tie two distant members together.

Treenail, Trenail

A cylindrical pin of hardwood used in fastening timbers together especially where materials are exposed to water action.

Truss rod

Metal rod used to replace or reinforce a carpentry truss or girder. Always used in tension.

Turnbuckle

A metal fastening that is threaded at one or both ends. The buckle is turned to draw two threaded tie rods together.

U-clamp

A U shaped strap whose terminals are threaded to receive a collar fastened by nuts. Used to envelope two or more timbers to close a joint.

U-strap

A U-shaped band pierced or formed to take nails, bolts, spikes or staples.

Wrought iron

The purest form of production iron having less than 0.15% carbon inclusion, malleable, tensile and corrosion resistant. Puddled or charcoal forms.

X-plate

A metal plate made in the shape of the letter X. Acts as a terminal for tie rods or bars.

 

 Appendix 2.Salzmanís Nail Types from 1208 to 1540.

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