#19 Straightening Paper Mould Laid Wires

Wire can be purchased in coils or on spools. In either case the wire comes off curved. In order to make a laid paper mould facing or backing it is necessary to make it much straighter.

Above, a piece of .0226″ diameter 1/2 hard phosphor bronze wire right off the spool resting on some of the same wire that has been run through a straightener and cut into lengths. While not perfectly straight, the processed wires can be made into a laid facing.

The major curve of the wire is called ‘cast’. This corresponds roughly to the diameter of the spool or coil. Another way that the wire is curved is called ‘helix’. The helix can vary, from very slight as shown above, or very ‘steep’ as shown below.

The same two pieces laying flat. The smaller circle of wire is the 1/2 hard wire mentioned above, while the larger circle is ‘full hard’ or ‘spring tempered’ wire of the same diameter. This wire has a more pronounced helix shape and won’t lay as flat.

A traditional way to straighten wire. The wire straightening blocks above and below are from Ron Macdonald’s collection of tools. These photos were given to me by Serge Pirard who studied with Ron and now makes moulds using many of Ron’s tools.

I tried to straighten wire this way but soon gave up!

Above and below are photos sent to me by Sergey Nasaev of Russia.

This is the wire straightener that I made using the information sent to me by Sergey. Ball bearings are stacked in pairs to create grooves which guide the wire back and forth to remove the cast. I expected that the wires should come out almost perfectly straight, like the pre-straightened wire I had been using for years. So, I was a little frustrated at first when the wires weren’t as straight. In retrospect this turns out not to be necessary or even desirable. If you try to make perfectly straight wires this way you may go crazy!

I made a second straightener out of steel with bronze rollers. The base plates of the first design were made of plastic. Steel, being much harder, can be more accurately calibrated. Now I can record the best settings for various sizes of wire so this unit can be used for all sizes of paper mould laid wire. Wire straighteners can be purchased but I chose to try to improve on what I had instead. (Besides, I like to make things and this looked like a fun challenge.)

A closer view of the steel and bronze wire straightener. The first set of seven rollers is used to remove the cast. The second set is used to remove any remaining curve caused by the helix.

The horizontal bank viewed from above. You can see that the rollers are set to bend the wire back and forth and less aggressively as the wire moves from left to right. Adjusting screws are located at either end of the slot between the rollers and are accessed through deep holes in the front plate. The two tightening screws are visible at the bottom of the photo.

The vertical bank. I have the best luck using five rollers here. Wire this light requires only 7 or 5 rollers per bank; heavier or harder wire needs more rollers.

The wire enters the horizontal bank of rollers. The cast is removed and slightly reversed by the first three rollers. Each trio of rollers creates a bending action as the wire is forced around the middle one. The remaining rollers form overlapping groups of three that apply a gradually diminishing amount of force. The wire is forced first one way, and then the other, to gradually change its shape from very curved to nearly straight.

After the first set of rollers are adjusted the wire will look fairly straight when viewed from directly above. But it may still have a noticeable curve when viewed form the side. This curve is a result of the helix and the second set of rollers have the job of removing it. Since this is much slighter they don’t have to push as hard. The wire lengths seldom turn out completely straight. If the straightener is calibrated right the wires repeatedly cycle from nearly straight to less straight and then back again; but fortunately staying within a useful range. I don’t fully understand all that is happening but think the wire has acquired some slight variation in the spooling or coiling process. Also wire twists slightly as it is unspooled. Either may cause the wire to shift slightly in the rollers, affecting the final shape. (This is my current theory.)

I pull the wire with this pair of wire cutters.

One jaw rides along the fence to keep the pulling angle constant.

When the outside handle hits the back stop the handles are squeezed to nip off a length of straightened wire. Then the cutter is moved back to the front stop to grab another length to begin again.

The top three bundles are .0226″ diameter 1/2 hard wire and will be made into laid facings for three moulds, two 12″ x 18″ moulds and one 10-1/2″ x 15-3/4″. The lower three bundles are .0254″ diameter wire and will be used to make the backing wires for these moulds. They are all to be “double-faced laid” (also known as “modern laid”) moulds.

Wire straightening is fairly new to me. I made moulds for about 25 years using wire that I purchased pre-straightened in lengths. After seeing a video of Ron Macdonald pulling wires from a coil I was inspired to try again. I like the idea of not needing a source of pre-straightened wire. I think that the hand pulled wires give a more interesting surface which carries over to the paper made on the mould (though this is pretty subtle).

I have tried to convey this information clearly. If something doesn’t make sense or if you would like further clarification let me know. I often have extra photos that can be posted and can also try to state things more clearly if I am aware of your questions.

Order of Operations

Paper Mould and Deckle Construction

Following is a list of the topics I plan to cover as I document some European style moulds and deckles that I am making. As you can see this is a big topic. Some fairly simple steps are covered but others will be rather vast. I won’t follow a strictly traditional method of making moulds; instead I intend to extensively document the method I have arrived at after almost 40 years in the trade. If all goes well over the next few months pages will be added to cover all of these steps in detail.

Season Wood

Rough Wood to just over final dimensions

Sharpen Tools

Prepare Frame pieces

Cut Frame Joints

Waterbar Mortises

Prepare Ribs

Drill Sewing Holes

Fit Ribs to Frame

Fitting Stays

Assemble and Glue Mould

Clean up Mould Frame and fit Brackets and Rub Strips

Pin Ribs and flatten Ribs

Straighten Laid Wires

Make Backing and Facing on Loom

Fit Wire Facing and Backing to Frame

Sew down Facing

Make Deckle Parts

Deckle Joints

Deckle Camber

Deckle Glue Up

Deckle Final Fit to Mould

Repairing a broken paper mould

A lot of gorgeous paper was made on this mould before it broke. I undertook to return it to a useable condition and learned a few things in the process.

The bottom of the broken side with rub strips removed. The insertion of the brass brace rod may have helped cause the break.
This frame was put together to hold the mould flat and to enable a router to cut a true surface on which to glue strips of new wood.
The first layer glued and screwed with epoxy and then machined (with the router) and ready to receive the next layer.
Beginning to repair the top of the mould. The (blue) blocks were clamped in place to guide the router to protect the chain wires where they overlap the frame. Notice that the wood that has been exposed is ‘just like new’. This mould has been in and out of water for years and has no remaining finish to keep water out. Yet beneath the darkened surface the wood is perfectly sound.
The frame has been cut away to just above the rib pins. You can see that the broken part of the mould has been almost entirely replaced, leaving only the narrow part in which the rib pins are inserted.
A longer area is routed away for the final top layer which will end up flush with the original top of the mould.

The mould had problems with sides that warped outwards. Braces had been added to restrain this but weakened the mould frame, resulting in a break which made the mould unusable. I decided to repair the mould by replacing parts of the mould frame with staggered strips of new wood which would be screwed down and glued with epoxy. The first step was to rough out a long area on each side to prepare a space to add the first layer.

The mould was then clamped into a specially made temporary frame. This provided a reference surface to enable a router to machine a true surface for glueing the new wood strips to.

New braces were installed along with the first layer. These are of a different design and should be much stronger than the ones they replaced.

After two layers of wood were added to the bottom, the second longer than the first, the mould was flipped over and clamped in the frame with the wire side up to repeat the same process of cutting away old wood and adding new strips but working from the top of the mould.

Great care was taken not to let the router bit contact the laid or chain wires. The remaining parts were carefully chiseled way to leave a good surface for gluing the next strip in.

A final layer was then added to bring the ‘patch’ flush with the top of the mould. The copper edging was tacked back into place, finishing the top repair.

One more layer of wood was added to the bottom and given a rounded shape to match the remaining original parts of the mould frame.

The first cut has been roughed out freehand with a router fastened to a long base to span the sides of the mould. The little ‘pedestals’ were left to give the router a surface to ride on. They were chiseled off before machining a smooth surface with a router in the temporary frame.
Two new braces were installed along with the first layer of wood. Threads were cut on both ends of 1/8″ brass rods. Each end was then threaded into a tapped delrin block. This gives a very strong connection.
A second layer has been added to the bottom of the mould.
The router is attached to a long base that spans the width of the mould.
The first top layer glued and screwed
The broken side of the mould showing the repair. One more layer will be added to the bottom to finish the repair.
Gluing on the last strip on one side of the mould.

What I learned.

The sight of the ‘like new’ wood that was exposed during the repairs reinforced my suspicions that any kind of finish which attempts to ‘protect’ a paper mould from water is most likely pointless. I think if the wood is allowed to dry thoroughly between uses the mould will be fine. I think wet wood (wood is ‘hydrophilic’) allows water to flow better (along the surfaces of the mould while sheet forming) than wood that has been covered with a water resistant (‘hydrophobic’) coating.

Preparing and testing wood before using it is important to prevent the mould from distorting when wet. Unproven wood can lead to multiple problems due to warping; deckles that don’t fit well, difficulty couching, and uneven stresses on parts of the mould which can shorten its life.

Questions

Rub strips made of boxwood or hornbeam (I can’t tell the difference) are nailed to the bottom edges to protect the mould from wear. On this mould (and others I’ve seen) these are attached in short sections that have gaps between them. The gaps seem intentional and it’s hard to see what purpose they serve. You can see here that a single piece of wood was nailed in place (the grain is continuous) and THEN sawn in two! The saw cut goes down into the mahogany frame. Was this to keep the strong, hard, possibly ‘ornery’ boxwood from distorting the frame? There may be another reason but I can’t think what it would be. The nails used to attach it are ring shank nails; possibly bronze boat nails.

Note

This my very first blog post. The choice may seem arbitrary and, in fact, it was! I hope to share a lot of stuff I’ve learned over the years but the order of topics will likely follow no discernible pattern. I hope some of these posts will be interesting to you.