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#56 Mould Maker’s Loom Part 9, Working with Wire

This doesn’t include straightening laid wires or sewing with wire. Both have been covered in earlier posts. In some ways this is a continuation of the last post, #55: Configurations of Laid Wire.

The wire used here is phosphor bronze. It is corrosion and fatigue resistant, stronger and much better for mould making than copper or brass. The wire used for chain wire twists is soft (annealed) and the wire that is straightened for laid wires has some temper. For years I used only spring tempered (full hard) for the laid wires but I have been told that 1/2 hard is what was used at Amies. I have since tried 1/2 hard, 3/4 hard and full hard to make laid wires. All worked well though the harder tempers may be a little more difficult to straighten.

Wire is often supplied in coils. A coil alone is not convenient and needs to be supported on a reel to make it easier to use.

Here is a reel that I made. The base is a thick plywood disc. It has a hole in the center so it can turn on a steel rod mounted in a block of wood.

I made two identical plastic discs to fit the reel. The lower one extends the size of the reel to better support the wire. The upper one floats on top of the coil to keep loops of wire from flipping off the top. This is probably not needed, but I had a bad experience early on with a coil that turned into a rat’s nest. A thin plywood disc can be fastened to the top after the wire is in place..

A closeup showing the coil sandwiched between the plastic discs. It’s important to keep track of the end of the wire so it doesn’t cross under some of the other loops. I always put the tag back on so the end doesn’t get lost.

Spools also need support to make it easy to take wire off for stringing up the loom or when sewing a mould.

This works well too. The end of a long bolt is clamped in the tail vise of the bench.

The vernier caliper makes it easy to identify sizes of laid wire. The micrometer is used to measure chain wire since differences in size can be less than a thousandth of an inch.

How Tightly can Chain Wires be Twisted?

A number of factors are in play here. How soft is the wire? How large is the wire? How heavy are the weights at the bottom of the wires? Another important consideration is the angle that the wires are splayed as they are twisted by the spindles.

This cross-section schematic is drawn to scale to compare the two angles of splay used in this loom. The red lines represent the chain wires. The black V-shapes show the inner surfaces of the wire trough that supports laid wires (one at a time) while the chains are twisted around them. The tightest twists can be made using flat-topped spindles, one of which is outlined on the left in light green. In the drawing you can see that these wires are splayed widely by the holes in the spindle. More relaxed twists are made using spindles with recessed tops, like the one on the right (outlined in turquoise). The recessed area effectively changes the height of the spindle so the wires are splayed less widely. Every spindle has both a flat end and a recessed end, either of which can be placed upright.

Here pink lines have been added to show what happens to the (previously red) wires when they are twisted around a laid wire. The flat topped spindles are used for laid facings; the recessed ones are better for making widely spaced backing wire.

When a laid wire is placed in the wire trough it rests a little less than 9/16″ above the top surface of the spindle rack.

The spindles stick up above the spindle rack exactly 3/8″. After the wire trough is screwed down, covering the spindles, the distance between the top of the spindle and the laid wire ends up a little less than 3/16″. If the spindles are inverted the distance from the top of the recessed area (1/8″ lower) to the laid wire ends up at about 5/16″. The 1/16″ diameter holes are drilled 7/16″ apart. The two angles of wire splay created by these dimensions work well, each for a specific purpose.

Testing Wire on the Loom

Determining how tightly two specific diameters of wire can be combined.

It is helpful to know the tightest spacing possible for different combinations of wire. This lets you choose among spacings that are sure to work and to more accurately predict the results when testing a different combination for the first time.

A Wire Test with Notes

You only have to do this once for each wire combination.

A relatively loose spacing is chosen for the first section of the test. After an inch or so has been made the counting wheel is changed and a slightly tighter spacing is created for the next section. Counting wheels are changed and increasingly tighter test sections made until the wire starts to bulge when it is lowered. When this happens it means that the limit of this combination of laid and chain wire has been reached.

Test for the wire shown above:

Wire Combination: .0254″ laid wire / .0118″ chain wire / tight twist spindles (flat on top)

20 wires were added in each section.

Spacing is in wires per inch.

spacingpins x clickspercentage space/wirenotes
18.207 x 554%/46%worked well
18.3524 x 1753.4%/46.6%worked well
18.4217 x 1253.3%/46.7%worked well
18.4727 x 1953.1%/46.9%worked well
18.5710 x 752.8%/47.2%started sagging but tightened up with twist
18.6923 x 1652.6%/47.4%same as above
18.7813 x 952.3%/47.7%this one sagged noticeably after twist

Conclusions from the test: It is safe to use this combination of wires with the first four spacings (and any of the looser ones before them if you wish). The next two intervals are iffy and the last one won’t work. If you want to use .0254″ laid wires for any of the last three intervals try the next smaller chain wire, (.0113″ in my case). This should do the trick and isn’t much of a change; the wire is only five ten-thousandths of an inch smaller in diameter.

When the spacing is too tight the web of wire will increase faster than the space in the loom does. That’s why the wire begins to bulge. In this photo the splayed chain wires are sitting down hard on the newest laid wire (lying at the bottom of the trough), forcing it to support the wire and all of the 1 lb. weights below. If the loom is working properly the wire and weights should be supported by the steel lift rod alone. The loom can only regulate the spacing if there’s a little bit of slack between the chain wires and each new laid wire. Some slack is needed to allow the wires to conform to the spacing being set by the loom. The section below may explain this a little better.

Start the Wires a Little Loose

The first laid wire of a facing is left loose on purpose This works just fine and is better than starting too tight. The chain and laid wires will even out within a wire or two and the spacing will be regular from then on.

You can see this clearly at the top of the middle section. It’s not as obvious in the bottom section.

It doesn’t matter exactly how loose the wire starts, it just needs to be a little loose. Notice that the chain and laid wires immediately settle into the spacing dictated by the indexing mechanism of the loom. One or two loose wires don’t matter anyway because a few extra wires are pulled out while fitting the facing to the mould.

Wire Weights

The weights should hold the wires taut without being so heavy that they stretch the wire. They should all weigh the same amount. And theoretically they should be just heavy enough to work well with the heaviest chain wire that will be used. I have used 1 lb. weights for many years but can no longer remember what happened when other sizes were used. It is possible that these weights could be a little lighter since now they are only used with annealed chain wire. I was working with 1/4 hard chain wire and this may have influenced the decision to use 1 lb. as a suitable weight.

#55 Mould Maker’s Loom Part 8, Configurations of Laid Wire


The Structure of a Laid Facing

Mould facings vary in how closely the laid wires are packed together. What is perhaps an average proportion is represented above with the spaces being a little wider than the wires. A 53%/47% split is shown between the size of the openings (spaces) and the size of the laid wires. Chain wires tend to be roughly half the diameter of the laid wires. The green arrow shows the laid wire diameter and the red arrow the chain wire diameter. The pink arrow shows the dimension of one wire + one space. This is the laid wire spacing. This is described in wires per inch in these posts. The orange arrow shows the open space between laid wires.


Some Traditional Configurations?

Below are some wire sizes used for Amies moulds taken from a copy of a chart that was given to me. The original listed British Standard wire sizes. The sizes are shown here in decimal inches. I added the percentages in the right-hand column to help compare and understand the relative proportions of the various facings. These twelve patterns were excerpted from a wider range of from 11 wires per inch to 46 wires per inch. (I don’t understand what the extremely coarse and extremely fine laid facings would have been used for. An 11 wire per inch facing would have had .040″ laid wires and .018″ chain wires. The extremely fine and delicate 46 wire per inch facing would have been made of .0108″ laid wires and .006″ chain wires. Were these ever made?)

Facings

Below: Amies laid facing patterns from 17 to 28 wires per inch:

Laid Wires per inchLaid Wire DiameterTwist/Chain Wire DiameterSpace : Wire
17.028″.0136″53% : 47%
18.028″.0124″50% : 50%
19.024″.0124″55% : 45%
20.024″.0116″52% : 48%
21.022″.0116″54% : 46%
22.020″.0116″56% : 44%
23.020″.0108″53% : 47%
24.020″.0100″52% : 48%
25.018″.0092″55% : 45%
26.018″.0092″53% : 47%
27.0164″.0092″57% : 43%
28.015″.0084″58% : 42%

For the range of facings shown above 7 sizes of laid wire would be needed. And 7 sizes of chain wire also. The laid wires progress in size in roughly .002″ increments and the chain wire in a little less than .001″. The percentages show a range of variation in the proportion of the wire structure from 50:50 to 58:42.

I’ve been working with these figures, using them as benchmarks to increase my understanding of what can work. I can’t say if these are representative of other European paper mould making traditions and makers.

Backings

These two configurations of Amies backing wire were listed:

Wires per inchLaid Wire DiameterChain Wire Diameter
6.34 Wove Backing.028″.0149″
5.34 Laid Backing.022″.0124″

My Career in Wire

For several decades making moulds I used only a few sizes of wire, all CA510 phosphor bronze. Laid wires were .0254″ diameter (22 gauge), .0226″ (23 gauge) and .0201″ (24 gauge). I have recently added .018″ laid wire stock to expand my range (largely as result of receiving the information above). For years my shop had only four sizes of chain wire; .008″, .010″, .013″ and .015″. I have recently added three more sizes between .010″ and .013″.

My stock of soft (annealed) wire

Five sizes I’ve used for years plus three new ones:

UsesDiameter ordered Tolerances Actual size received
Sewing watermark profiles.005″.0050″
Chain wire for facings
Sewing wire for wove facing
Sewing wire for fine laid moulds
.008″.0080″
Chain wire for facings
Sewing wire for laid moulds
.010″.0102″
Chain wire for facings (new).0108″+/- .0003″.0106″
Chain wire for facings (new).0115″+/- .0003″.0113″
Chain wire for facings (new).0121″+/- .0003″.0118″
Chain wire for wove backing
Sewing wire for wove backing
.013″.0130″
Chain wire for laid backing.015″.0150″

The actual sizes were determined with a micrometer. The three new sizes were intended to evenly fill a ‘wide’ gap between .010″ and .013″. This was a little tricky when taking into account the tolerances (+/-.0003″) that were offered by the supplier. In a worst case scenario by ordering a spool each of .0108″ and .0115″ wire I might have received one spool of .0111″ (.0108″ plus ‘three tenths’) and one spool of .0112″ (.0115″ minus ‘three tenths’). Having two sizes only one ten thousandth of an inch apart wouldn’t have helped much! In the end it worked out pretty well but with a wider gap than wished for between the .0118″ and .0130″ sizes. Adding .009″ wire would fill another gap but it likely wouldn’t get much use.

My stock of tempered wire

Wire temper will be covered in the next post.

Gauge (AWG)Actual sizeTemper
Close to 25 gauge.0183″ 3/4 hard
24 gauge.0201″3/4 hard
23 gauge.0226″1/2 hard
22 gauge .0254″Full hard

It is possible to purchase tempered wire pre-straightened. I used pre-straightened wire exclusively for decades. One difficulty is ordering the right lengths to avoid excessive waste (you must plan carefully to avoid too-short leftover pieces). It can be expensive to ship long pieces.


Some facings and backings I’ve made

spacinglaid wirechain wirecounting wheel‘clicks’arithmetic*
118.57.0254″.010″ (1/4 hard)*10 pins710 x 13 = 130
130/7 = 18.57
220.8.0254″.010″ 8 pins58 x 13 = 104
104/5 = 20.8
321.67.0254″.010″5 pins35 x 13 = 65
65/3 = 21.67
47.8 backing
(wove)
.0254″.013″3 pins5 3 x 13 = 39
39/5 = 7.8
55.78 backing
(laid)
.0254″.015″4 pins94 x 13 = 52
52/9 = 5.78
620.8.0226″.0113″8 pins58 x 13 = 104
104/5 = 20.8
721.67.0226″ .010″5 pins35 x 13 = 65
826.0226″.008″2 pins)113 x 2 = 26
921.67.0201″.0113″5 pins35 x 13 = 65
65/3 = 21.67
1022.0201″.0113″221322 x 13 = 286
286/13 = 22
1125.0183″.0106″251325 x 13 = 325
325/13 = 25

*The reason that 13 is used in every calculation is that the lead screws have 13 threads per inch. Thus, if you turned the crank (and the two linked lead screws) one full turn each time you add one laid wire you would create a spacing of 13 wires per inch. (It would take thirteen 360 degree, full-turn adjustments to lower the twisting mechanism one inch). Turning the crank 1/2 turn would double the number of adjustments per inch thus yielding 26 wires per inch. Using counting wheels (with different ratios of pins to ‘clicks’) to turn the crank fractionally yields many in-between spacings. 88 of these are listed at the end of the post.

Notes on the above:

#1: About 90% of the moulds I sold used this spacing and combination of wires. I no longer use 1/4 hard wire for this 18.57 wire per inch facing. I use .0118″ diameter soft wire for the chain wire. This wire is only .0016″ larger diameter but about 33 % stronger than .0102″. The chain wires are the most delicate part of a paper mould so this is welcome.

#2 and #3: The laid wires start to get a little tight here compared to the Amies patterns. Facing #2 is about 47%/53% with the spaces less than the width of the wire. Facing #3 is even tighter with a 45%/55% split. In retrospect these facings seem heavier than necessary with undersized chain wires.

#4: This the backing wire configuration used for all of my wove moulds based on a wove mould examined early on. This is a finer spacing than the Amies pattern.

#5: Both of these backings have three half-twists between laid wires. This chain wire (.015″) is the heaviest used so far with this loom.

#6: Note that the same spacing was used with #2 above. But in this case the more widely spaced laid wires would be slightly lighter weight with stronger chain wires. Facing #6 roughly mimics the 21 wire Amies facing.

#7: This spacing works well with the new .0113″ chain wire which I think is better than the .010″ shown.

#8: I sold some moulds with this wire combination. Now I think the .008″ chain wire is pretty delicate and best avoided. This spacing could use .0183″ laid wires with .0102″ chain wires to be closer to the Amies pattern. These wires are tightly packed. They worked though.

#9: Notice that this is the third use of this laid wire spacing. It is the closest to the 22 wire Amies pattern and I think the best of the three. The laid wires are less densely packed and have heavier (stronger) chain wires.

#10 and #11: I was recently asked to make two very large facings based on the Amies patterns for 22 wires per inch and 25 wires per inch. Both worked very well with this loom.

Conclusion: I wish I had known about the Amies patterns early on. I would have spread the laid wires a little wider and used heavier chain wires. I didn’t have as much information as I should have had. On another note, it might have been helpful to work closely with papermakers to learn more about the relationship between wire (sizes and spacing) and the formation and ‘look’ of paper made on them. (As mould makers at Amies presumably did). Alas, most of my business was conducted from afar and this was not practical.


A Ridiculous Number of Possible Spacings between 15 and 32 Wires Per Inch.

Why is This Important? Only a few of these are likely to be used by any one mould maker but all are potentially useful. If you are trying for a certain spacing using only the various diameters of wire that you already own, having the ability to adjust the spacing by minute amounts can be very useful. One of these spacings could turn out to be ‘just the thing’ to work well with the characteristics of the wire at hand.

wires per inch
(pins x clicks)
wires per inch
(pins x clicks
wires per inch
(pins x clicks
wires per inch
(pins times clicks)
15.00: (15 x 3)18.20: (7 x 5)21.27: (18 x 11)25.07: (27 x 14)
15.17: (7 x 6)18.35: (24 x 17)21.36: (23 x 14)26.00: (1/2 turn)
15.60: (6 x 5)18.42: (17 x 12)21.67: (5 x 3)27.00: (27 x 13)
15.74: (23 x 19)18.47: (27 x 19)21.94: (27 x 16)27.08: (25 x 11)
15.89: (11 x 9)18.57: (10 x 7)22.00: (22 x 13)27.44: (19 x 9)
16.00: (16 x 13)18.69: (23 x 18)22.10: (17 x 10)27.63: (17 x 8)
16.06: (21 x 17)18.78: (13 x 9)22.29: (12 x 7)27.86: (15 x 7)
16.42: (24 x 19)18.91: (16 x 11)22.45: (19 x 11)28.17: (13 x 6)
16.47: (19 x 15)19.00: (19 x 13)22.75: (7 x 4)28.36: (24 x 11)
16.61: (23 x 18)19.06: (22 x15)23.00: (23 x 13)28.60: (11 x5)
16.71: (23 x 18)19.12: (25 x 17)23.11: (16 x 9)28.89: (20 x 9)
16.90: (13 x 10)19.50: (3 x 2)23.21: (25 x 14)29.25: (9 x 4)
17.00: (17 x 13)19.93: (23 x 15)23.40: (9 x 5)29.55: (25 x 11)
17.11: (25 x 14)20.00: (20 x 13)23.64: (20 x 11)29.71: (16 x 7)
17.33: (4 x 3)20.09: (17 x 11)23.83: (11 x 6)29.90: (23 x 10)
17.55: (27 x 20)20.22: (14 x9)24.00: (24 x 13)30.33: (7 x 3)
17.59: (23 x 17)20.31: (25 x 16)24.14: (13 x 7)30.88: (19 x 8)
17.64: (19 x 14)20.43: (11 x 7)24.38: (15 x 8)31.57: (17 x 7)
17.73: (15 x 11)20.58: (19 x 12)24.56: (17 x 9)31.78: (22 x 9)
17.88: (11 x8)20.65: (27 x 17)24.70: (19 x 10)31.91: (27 x 11)
18.00: (18 x 13)20.80: (8 x 5)24.82: (21 x 11)
18.06: (25 x 18)21.00: (21 x 13)24.92: (23 x 12)
(next column)21.13: (13 x 8)25.00: (25 x 13)

The table above is based on a set of 12 double-sided counting wheels. The smallest number of pins (around the circumference of a wheel) is 3; the largest number is 27. The 26 pin wheel is left out because it turns out to have little value. (A 26 wire per inch spacing can be made simply by turning the crank 1/2 turn for each laid wire added.) Otherwise the set is complete with all numbers from 3 to 27 included.

#54 Mould Maker’s Loom Part 7, Some Other Important Parts

The larger structures and functions of this loom have been described in the last six posts. Some small but essential parts have not received much attention and these are more fully explained here.

Spindles and Spindle Drive Weights


Spindles

A spindle is required for each pair of chain wires so a lot of them are needed to produce a large facing. The most tightly spaced spindle rack has spaces for 43 spindles, that’s the most that could ever be needed for this loom.

The spindles are made of 5/8″ diameter acetal plastic rod. They are 7/8″ long.

Each spindle has a flat end and a one that is recessed 1/8″. The spindles are placed with flat ends up when making laid facings. This splays the chain wires at a wide angle to twist the chain wire tightly. The spindles are turned over with recessed ends upward when making backing wire. This causes the wires to be splayed less widely to help create the wider spaces between backing laid wires. This is not strictly necessary but gives a better looking result with the twists being more even.

Above, the twists are more symmetrical if the recessed spindles are used. (Laid backing made with .0254″ laid wires and .0150″ chain wires.)

Here with the spindles’ flat side up the twists are tighter and the twisting less symmetrical. The ‘eyes’ are larger and don’t grip the laid wire as tightly.

The holes for the wire are 1/16″ diameter and are spaced 7/16″ on center.


Spindle Drive Weights

A drive weight is needed for every spindle so a lot of these are needed too.

The ones that are used weigh 2.2 ounces. The next smaller size (1.75 ounce) didn’t work well.

All of the drive weights have a length of braided fishing line attached. The 14″ length used here isn’t critical but all should be the same so the weights will line up evenly along the front of the loom. Each knot is fixed with a drop of cyanoacrylate glue. As shown in this photo the free end is tied to a cotter pin. The pins are altered a bit; they’re clipped short and the eyelets smashed shut with vise grip pliers so they don’t stick out as far when inserted into the attachment holes in the cord reel.

The cotter pins start out like this. Plain wire can work but the half round wire of cotter pins is ideal.

This fishing line works well. The cord should be flexible and soft so it can flatten to grip the sides of the spindles.


Wire Spacers, Wire Slides and Weights

Below the spindles and drive weights are the wire spacers, wire slides and wire weights. The foam board wire spacers hold the wires apart to prevent them from twisting around each other. The wooden wire slides also have this function but are made for their lengths to be adjustable. A couple of inches of free, bare wire needs to be maintained just below the twisting mechanism. The adjustable wire slides make it possible to keep this space from being too big or too small as the wire spacers are removed a row at a time. The bottom bars of the slides also serve as attachment points between the chain wires and the weights.


Wire Spacers

These are just pieces of foam board, 3/4″ wide and 3″ long.

This little saw was chucked into a drill press and a fence was clamped to the table to cut slots into the sides of the spacers. The slots are just deep enough to match the spacing of the holes in the spindles, 7/16″.

Hundreds of these are needed, as many as a dozen for each pair of chain wires for the very largest facings. If you don’t accidentally step on them they last a long time. I made a box of these 40 years ago and haven’t needed to make more since.


Wire Slides

This photo shows the adjustable function of the wire slides. The wire slides also serve to attach the chain wires to the weights. The ends of the chain wire are twisted together below the lower cross piece next to the little screw eyes.

The small holes are spaced a little closer than the holes in the spindles (a little less than 3/8″ apart). This way when the top bar of the slide is pushed up against a foam board spacer a slight binding action is created. This helps hold the two parts in place on the wires.

The 1/8″ diameter dowels are glued into the upper part of the slide. These wire slides also need to be made in quantity; one for each spindle.

The slides are 4″ long and 7/8″ wide and can adjust about 3″. The length of the crossbars limits the minimum chain spacing for this loom to just over 7/8″; any closer and the parts would bump into each other as they turn. A 15/16″ chain wire spacing can be made with no problems. Making anything smaller would require some research and a whole new set of parts; smaller spindles, spacers and slides.


Wire Weights

The weights attach to the slides like this. The cord attached to the weight should be long enough that the dowels can’t reach the weight when the slide is fully closed.

These weights are 3/4″ diameter steel rods 8″ long. They hold the chain wires under tension as they are twisted into place. These one pound weights work well for all sizes of wire from .008″ to .015″.

The weights need to hang from cords so they can spin freely. When the spindles turn the motion is carried down the wires to the weights. These develop momentum (like flywheels) so they turn a little too far before starting to spin back. While a facing is being made the weights continuously oscillate at the bottom ends of the wires. The length of flexible cord mostly isolates this action to the weights so it doesn’t interfere with the wire twisting action happening above.

Unfortunately these weights turned out to be slightly magnetic. Sometimes it is necessary to slide a little piece of hose over a weight to keep it from sticking to the one next to it.

#53 Mould Maker’s Loom Part 6, More on The Wire Twisting Mechanism

This is a self contained mechanism that is fastened to the front of the traveling beam of the loom. The spindle rack is the base of the twisting mechanism; all the other parts are attached to it. It is made from a single piece of wood, as long as the longest laid wire. It has 5/8″ holes bored through it at regular intervals to hold the spindles. A cord reel passes from end to end. It is attached by end plates to the spindle rack. A crank is affixed to the right-hand end. The crank’s back and forth rotation is limited to about 180 degrees, between the fixed stop and the adjustable stop. This hand powered crank supplies the effort to turn as many spindles as are required to make any size facing or backing. A drive weight and cord are hooked up for each spindle used. The back end of each cord is fixed in the cord reel and the front is tied to a 2.2 oz. lead weight. Each cord wraps three times around a spindle to turn it by friction. When the crank is rotated back and up it ‘reels in’ the cords causing all of the weighted spindles to turn clock-wise simultaneously. This allows all of the chain wires to be twisted at the same time. This simple cord/spindle mechanism has a couple of important qualities that I will attempt to describe in the following text, photos and videos.

Spindles are normally placed in the center of the spindle rack when a wire facing is being made. For these photos a single spindle has been hooked up near the crank so most of the working parts can be shown together. The wire trough has been removed to reveal the spindle, weight and cord.

Some of the parts are identified here.

The left hand end of the mechanism showing the plywood end plate, and a washer, cap and machine screw that hold this end of the cord reel in place.

A spindle is rigged by wrapping a cord three times around it. The 1/8″ brass rod at the front of the spindle rack holds the front of the cord up to keep the loops from crossing over each other.


Understanding How it Works

The crank is limited to turn (back and forth) about 180 degrees. The reel is a larger diameter than the spindles so the spindles end up turning a little MORE than 180 degrees. This is important and will be explained later. As you can see above when the spindles have no load on them they will simply turn back and forth with the crank.

A repeat of the first video showing an unloaded spindle turning back and forth.

I am placing gentle pressure on the side of the spindle with my finger. Under load the spindles turn clock-wise and do not ‘back up’. This is the first ‘beauty’ of this simple mechanism; a simple back-and forth motion of a crank can be converted to a ‘one way’ rotation of the spindles. This allows wires to be twisted in one direction to form chain wires. But if you look closely you can see that the spindles gain a few degrees with each rotation of the crank.

These extra few degrees of rotation are intentional and the stops of the crank are set to provide it. This video attempts to show the constant ‘re-calibration’ of all of the spindles (the second beautiful thing about this simple string and weight arrangement) that happens when a facing is being made on the loom. I am using my finger to simulate the stopping action usually provided by the pairs of (as yet untwisted) chain wires being raised (by the treadle and lifting mechanism) to engage the slots in the wire trough. (If the trough were in place you wouldn’t be able to see anything. ) My finger is allowing the holes in the spindle to re-align each time the crank is released, clumsily simulating the regulating action that is normally provided by the lift mechanism.


Repeating Cycle of Twisting Mechanism Only (other actions of the loom not included here)

(1) At Rest

The crank is ‘parked’ against the lower stop and the weight has dropped as far as the cord will allow; the resting position for the entire mechanism. The pair of spindle holes are oriented front and back with hole “a” in back.

(2) Crank Reels In

The crank has been rotated up to the fixed stop (and held there), reeling in the cord and causing the spindle to rotate a little more than 1/2 turn. Hole “a” has moved around to the front. The holes are not aligned directly front to back, having rotated past the center line. I’ve added imaginary chain wire here (red) and an imaginary wire trough slot whose sides are described with the parallel black lines.

(3) Chain Wire Lifted into Slot

The crank is still being held against the upper stop so the rotation of the spindles continues to be ‘frozen’. However the loom treadle has been stepped on, lifting the upside down “Y” up, engaging the splayed wires in the ‘slot’. The wires are bent sideways a little by the edges of the slot because the holes aren’t directly below. The blue line shows how far ahead the spindle has turned compared to the green line which is drawn straight across.

(4) Crank Returned to Lower Stop, Spindles Re-Calibrated

The operator’s foot remains on the treadle holding the wires up so they are still engaged in the slot. The crank is on its way back down to the lower stop thus unreeling the weighted cord. This causes the spindle to reverse by a limited amount. At a certain point the engaged wires prevent the spindle from turning further and the cord begins to slip. By the time the crank has been released completely to rest against the lower stop the spindle has re-calibrated (a tiny bit behind the center line which is OK). Each time this cycle is repeated all of the many spindles in use will automatically re-align. That way spindles don’t get behind or ahead and all are always ready for the next twist.


Two laid wires are being added here. One is already in place. If you watch the white wire spacers behind the weights you can see them reverse a little just as the weights drop down. This shows the spindles re-aligning.

#52 Mould Maker’s Loom Part 5, The Wire Twisting Mechanism

Assembly of the Mechanism

Examining the parts as they are put together may be one way to understand its workings.

I don’t usually assemble the parts on the loom as I will do for this post. Normally the various spindle racks (a different one is needed for every chain spacing) are pre-assembled except for certain parts that they all share. For instance there is only one cord reel and crank needed for this loom. There are enough spindles and drive weights to make the largest possible facing. When a facing or backing is made only the number of these actually needed are attached.

Spindle Rack

This spindle rack started out as a long piece of yellow birch with a simple rectangular cross-section (3″ wide by 1-1/8″ thick). These pieces should be the same length as the frame cross-pieces and the traveling beam, 42″ in this case. After the large spindle holes were bored two cuts were made on the table-saw to create the shape shown here. The thick back side provides support when screwed to the traveling beam; the front side is narrowed to 1/2″. This is the amount that the (7/8″ tall) spindles are set down into the rack.

A strip of polycarbonate screwed to the bottom prevents the spindles from dropping through the holes and provides a slippery surface for them to turn on. These holes were bored with a 5/8″ forstner bit and the spindles had to be turned down a bit on a lathe to turn freely. A simpler method is described at the end of the post.

The strip overlaps the hole just enough to support the spindles without blocking the small holes through which the chain wire will pass.

The partially completed spindle rack can now be fastened to the loom; specifically to the traveling beam of the indexing mechanism. The dark colored spot is one of five acetal ‘plugs’ sunk into holes. They are cross-drilled and tapped to receive the threads of the machine screws. Two of the five machine screws are visible here.

The rack has been attached at the center only.

All five of the machine screws have been tightened to firmly attach the spindle rack to the traveling beam. Wood screws could also be used but would be difficult to drive from behind.

A view from beneath.

End Plates

These blocks are screwed in place; one at each end.

They provide a way to fasten the end plates in place.

The end plates are mirrors of each other.

The right-hand end plate has a few extra holes for attaching the two stops.

These limit the motion of the crank to about 180 degrees (back and forth only). The top one is fixed and the bottom one is adjustable.

Cord Reel and Crank

The cord reel is made of 3/4″ diameter acetal rod. A line of holes has been drilled into it for nearly its full length. The spacing of the holes isn’t too important. (about 1/4″ is good).

At one end a crank is attached by a machine screw in a threaded hole. The square shank and mortise allow the crank to be re-positioned. This makes it possible to correct the orientation of the reel after attaching the cords and drive weights.

Two pairs of metal posts (located at thirds) keep the reel from being pulled forward when drive weights are attached. The reel needs to be elevated above the top of the rack to provide room for the cords. Plastic shims placed over the posts elevate the reel in the middle. The ends of the reel are already held up by the holes through the end plates.

The cord reel is ready to insert through the big hole in the end plate. A large washer keeps the crank from rubbing against the end plate.

The reel passes through the left-hand end plate in the same way.

It is held loosely in place by another washer, a plastic cap and a small machine screw.

Wire Trough

This is the wire trough which covers the row of spindles. The V shape makes it easy to slide laid wires in (one at a time). The cross-wise slots allow the pairs of chain wire to remain spread out (when lifted) so laid wires can pass between them. The slots also engage the lifted chain wires to prevent the spindles from turning backwards as the crank and reel are reversed.

This design is more complicated than it needs to be and I will show a simpler version at the end of the post. These were made this way to solve a problem; it was possible for the loops of cord that are wound around each spindle to slip up off the top. This happened when a drive weight was accidentally bumped from below. Two changes were made. First, the spindles were lengthened from 3/4″ to 7/8″ so they would stick up farther above the cord loops. Second, the wire trough was shaped to enclose the tops of the spindles and prevent the cord from slipping up that high. Both work very well to prevent these occasional accidents but simply lengthening the spindles may have been enough.

The trough lying on its side. The very narrow saw cuts were made with a Japanese style backsaw held in a cross-cut jig.

The wire trough is laid upside down to show how the top of the spindle is enclosed to prevent the cord from slipping off the top.

The holes in the cord reel receive these tiny cotter pins to connect the weighted cords to the reel. The cotter pins start out too long and have to be snipped off a bit. The knots at both ends of the cord are fixed with ‘Crazy Glue’. As mentioned the spacing of the holes is not critical, the location of each cord attachment just needs to be fairly close.

The cords are fitted with the holes in the reel pointing straight up. (Just to make it easy to put the cotter pins in). After all of the spindles are hooked up the crank can be loosened and slipped out of its square mortise so that the weights can be reeled in the right amount. (If they hang down too low they get in the way.) After the adjustment is made the socket of the crank is firmly tightened over the square shank of the reel.

The ends of the cotter pins should start at the back and end up in the front when the weights are cranked up fully. This way the pins and knots stay on top as the reel is turned back and forth. The purpose of the 1/8″ brass rod fastened along the front is to elevate the cords at the front of the spindles. This prevents the cord loops from lapping over each other.

This photo provides a good illustration of the problem mentioned a few photos back. If a weight is bumped from below the loops of cord might loosen and slip off the top of the spindle. This was even more likely with the original spindles which stuck up only 2/3 as far as these do. The more elaborate wire trough I now use prevents this from happening.

Chain wire is added with the wire trough elevated. This process is covered more fully in other posts.

When the wire trough is lowered over the spindles and screwed down the assembly is complete. For this post only three chain wires have been used. Normally there would be many more chain wires, spindles and weights.

Older, Simpler Parts

When it came to time to make a second loom I tried to refine the design using everything I had learned over the years. But some of the original features were very functional and easier to make.

An example of the original wire trough made of pine from a lumberyard.

Pairs of screws work as little ‘jacks’ which are adjusted to hold the bottom of the trough just above the spindles. If longer spindles were used (7/8″ or even 1″) longer screws could easily be adjusted to fit. This might solve the ‘cord over the top’ problem mentioned earlier in this post.

The wire racks were also a little crude but worked well for as long as this loom was in service.

These were also made of pine which has some advantages. The original spindles were cut from 5/8″ diameter acetal rod and filed smooth on the ends. (I didn’t have a lathe). This material is manufactured slightly oversize so the 5/8″ holes drilled in the wood fit too tight. The holes were easy to enlarge with a strip of coarse sandpaper and dowel chucked into an electric drill. As you can see above the spindles can be quite loose.

#51 Mould Maker’s Loom Part 4, The Lift Mechanism

The purpose of the lift mechanism is to repeatedly lift the wire facing so that laid wires can be added at the bottom. A treadle and lift lever (not pictured, at the bottom of the loom) pull down on the middle of a “V” of rope. (The top ends of the V are visible here.) The ends of the rope pass up and over a pair of large wooden pulleys. The wooden pulleys reverse the rope’s direction to lift two smaller steel pulleys attached to the short upper lift beam. This raises the entire lifting beam assembly one half inch. Attached to the bottom of the long lower lifting beam is the steel lifting rod. Weighted wires will hang over this rod to form chain wires when making a laid facing (or backing) on this loom. When pressure on the treadle is released the rope relaxes and the lifting beam drops back to its lower position.

Large Wooden Pulley Assembly

Two large pulleys are made from layers of birch plywood. Each one is a sandwich of one smaller disc and two larger ones. Steel washers and nuts are added to both sides of each pulley to bind all of the parts tightly together. Both pulleys turn together as a unit and only rotate (back and forth) a few degrees, about an inch at their perimeters.

Loosely placed at the sides of the cross-piece above are two wooden blocks which attach the pulleys to the frame. Each is fitted with a nylon bushing for the threaded rod/axle. It might seem sub-standard to use threaded rod as an axle and nylon bushings as bearings. But it is a simple solution that has proved to work very well. The original pine loom had no bearings at all and worked for decades without any problem. Nylon bushings are more durable than pine and have the advantage of being easily replaced.

The wooden pulley assembly in the process of being slid into place over the four carriage bolts that secure it to the frame.

3″ Offset from Front of Loom Uprights

The plywood pulleys are sized and placed so that the rope passing over the back is centered over the treadle lever at the bottom of the loom. More importantly, the rope coming down off the front of the pulleys should be exactly centered over the lifting beam. A wire facing being made on the loom will take the form of a vertical plane hanging directly below the lift beam. This loom is designed for that plane to be located exactly 3″ in front of the faces of the loom frame uprights. The lifting beam and all its moving parts must be centered in this plane as shown above. The red line indicates the front face of one of the uprights. The green line shows the centerline of the upper lifting beam (and other attached parts below). The purple arrows indicate that the rope is also centered in this plane.

Later when the twisting mechanism is attached the spindles (that fit in these holes) will also be centered 3″ in front of the loom uprights.

Lifting Beam Assembly

Here the lifting beam is off the loom and partly assembled.

The protruding ends of the bolts fit into holes drilled into the lower part of the beam.

The small steel pulleys are bolted to the upper lift beam with nuts recessed at the bottom.

Directly below each steel pulley a steel bushing is flanked by a pair of washers. When the 5/16″ carriage bolt passing through them is tightened (to connect the lower lift beam to the upper one) the three separate steel parts (washers and bushing) are squeezed tightly together to act as a unit. The bushings are 5/8″ long with a 5/16″ bore. The washers are more precise than average washers, all having the same thickness and snug fitting holes.

This shows the purpose of the washer and bushing ‘units’ after the lift beam assembly has been installed on the loom. The bushings slide smoothly up and down (through holes drilled in the steel angle) to guide the lift beam. The washers at the top and bottom limit this motion to one half inch. The beam was set to be neither up nor down just for the photo; normally (with the treadle released) the upper washer rests on top of the steel angle. When the treadle lifts the beam the lower washer is pulled up against the underside of the angle.

Transferring Motion from Treadle to Lift Beam

When the treadle is pushed down with the right foot the lever pulls both halves of the rope down the same amount. This is about 1-1/2″ (the rope stretches a bit when pulled tight). The large steel weight serves only to lift the lever and attached treadle when foot pressure is released.

The upper ends of the rope pass over the wooden pulleys from the back. The motion of the rope is reversed by these pulleys to lift the beam assembly at the front. The lower steel pulleys give some mechanical advantage since they only lift the beam 1/2″ for the full inch that the rope travels under them. This makes it easier to raise the facing and attached wire weights which can weigh as much as 45 lbs. if the facing is very large. The ends of the rope are fixed to the top two carriage bolts where they are clamped between washers and extra nuts. These bolts are extra long for this purpose. This is where the rope is adjusted for length to work properly.

The loom frame equipped with the complete lifting mechanism.

#50 Mould Maker’s Loom Part 3, The Indexing Mechanism

The purpose of the Indexing Mechanism is simply to control the downward motion of the Traveling Beam (above). This beam is supported at both ends by square nuts; each fits into a notch created for it. These in turn are supported by a pair of Lead Screws, which are just full length pieces (3′ long) of 1/2″-13 threaded rod, available at hardware stores.

The lead screws are attached to 1/2″ x 4″ Machine Screws with connecting nuts. These machine screws have been inserted down through the Chain Sprockets and fastened to them by set screws. The sprockets are supported by the Chain Race and Upper Cross-Piece. The lead screws (and traveling beam) essentially hang from these two sprockets. A Timing Chain made of a loop of roller chain connects the sprockets so they always turn together and at the same rate. The Top Crank, on the right, is turned by the operator’s hand to create the motion. Each complete turn of this crank (counter-clockwise) lowers the traveling beam 1/13th of an inch. The Counting Wheel Assembly at the top left regulates the incremental downward movement of the traveling beam so that a variety of laid facings and backings can be made.

As the lead screws are turned square nuts move down, carrying the traveling beam and attached twisting mechanism with them.

Chain Race

The chain race is simply a piece of 1/4″ plywood with holes in the right places for the lead screws and for screws to fasten it in place. It provides a wider surface to support the loop of chain. The circular oil stain was left by a steel washer, one of a pair at each end on which the sprockets turn. The washers lift the sprockets up to mesh smoothly with the chain, reduce friction and bear the weight of the traveling beam and the twisting mechanism.

Chain Sprockets and Modified Machine Screws

The chain sprockets have 14 teeth and a 3/8″ pitch. The number of teeth doesn’t matter much as long as both sprockets are the same. They were purchased with a 1/2″ finished bore and each have two set screws. High grade 1/2″ diameter x 4″ long machine screws were chosen because their true 1/2″ shank diameter closely fits the sprocket bore to ‘run true’ (unlike standard hardware store bolts which tend to be under-sized). Flats were filed for the set screws and the heads were drilled and tapped for 1/4-20 threads.

Top Crank Attachment

Two washers elevate each sprocket so the teeth will line up with the roller chain. A hexagonal recess chiseled in the top crank provides a positive connection to the crank.

The right hand sprocket assembly in its place. It will be linked to the other sprocket with a loop of roller chain.

Counting Wheel Attachment

A circle of birch plywood with a hexagonal hole provides a firm base to attach counting wheels using a 1/4-20 machine screw like the one used for the crank.

Timing Chain

The timing chain is intentionally a little loose and is kept within bounds by the plastic post and a small strip of wood nailed to the front. The roller chain doesn’t need much lubrication and will run freer if the grease is cleaned off.

In use the front side of the loop runs straight since the right hand crank is turned counter-clockwise. The crank can be turned the other way (clock-wise) to return the traveling beam to the top of the loom.

Counting Wheel Assembly

This is a device that makes noise (clicks) that can be counted to lower the traveling beam a very specific amount, the distance of one laid wire plus one space. Depending on the diameters of laid wire and chain wire used this can vary a lot.

A rubber band is wound around and around so the pawl will click as it passes steel pins on the counting wheel. In this photo the pawl is disengaged.

I made a complete set of these counting wheels having from 3 pins to 27 pins so I can experiment with different sizes of wire and different spacings. Most of these wheels won’t get used. This makes it possible to make any even number facing (17 wires per inch, 18 wires per inch, 19 wires per inch, etc.) all the way up to 27 wires per inch. Even number backing is also possible with three half-twists between wires. (5, 6, 7, 8, and 9 wires per inch more than covers this need). Many in-between sizes are also possible. It’s just a matter of doing the arithmetic, calculating the number of pins to use and how many clicks to turn the crank (and pairing this with the right wire sizes).

A counting wheel with 10 pins is given 7 clicks to lower the traveling beam the distance of one laid wire and one space. If a facing was actually being made this would make a laid wire spacing of 18.57 wires per inch. This video only demonstrates the counting wheel action and the the other mechanisms are not being used.

The upper part of the indexing mechanism completed.

Connecting the Lead Screws

The lower end of each machine screw is connected to this extra long nut with a 3/32″ roll pin. As you can see these pins are also used to attach the upper end of the lead screws to the connecting nuts. It’s a bit tricky to drill these small holes through the layered steel parts without breaking a drill. It helps to snug the parts up with added hex nuts (maybe pack the lead screw in teflon tape?), to clamp things securely on the drill press and to use cutting oil. (The cutting edges of the twist drill tend to catch when exiting the inside threaded surfaces.) After assembly these parts should be a little loose; the lead screw and machine screw ends shouldn’t quite touch. The amount of force put on these parts is minimal and having some play helps them run smoothly.

A piece of plywood holds the traveling beam level while the lead screws are hooked up.

The bottom ends of the lead screws are held in place by the bushings in the bottom cross-piece. Only about an inch hangs down into the hole.

Calibrating the Lead Screws and Beam

After the lead screws are attached the notches in the beam can be lowered down over the square nuts, ‘trapping’ them so they can’t turn. The beam can be leveled (calibrated) simply by lifting one end of the beam and turning the square nut one way or the other. Each quarter turn raises or lowers that side 1/52″ (.019″) so the beam can easily be leveled to the frame within that tolerance (which is close enough for all practical purposes).

If you want to get closer the connecting link can be removed to shift the chain slightly on one of the sprockets. This lowers or raises that side between .005″ and .006″ per tooth.

Traveling Beam Backing Iron

The traveling beam slides along the front of the two loom uprights. It has a tendency to sag forward at the top so this piece of steel angle is bolted on to limit this. This metal rule is used to gauge a small space which must be left as the steel angle is cinched tight between two nuts (the back nut is hidden behind the steel angle). The rule is .020″ thick (.5mm) which works well. The traveling beam is made of a heavier wood (Oak) to help it move down the loom smoothly.

#49 Mould Maker’s Loom Part 2, The Frame

Designing and building a functional loom requires working out details of how all of the mechanical parts interrelate before starting construction. This post is limited to decisions and dimensions that must be incorporated into the parts of the frame. Many of the dimensions used are somewhat arbitrary but I will emphasize those that directly affect the capabilities of the finished loom.

The frame of this loom is fairly simple. The four main parts are made of Tulip Poplar; final dimensions of these were largely determined by the the larger planks they were cut from. Upper and lower cross-pieces, 1-7/8″ x 1-7/8″ x 42″ are bolted to two uprights, 1-3/4″ x 3″ x 71″ tall. These are spaced 22-1/4″ on center. Two 1/4″ thick plywood panels are screwed to the back to brace the structure. The loom is lag bolted and screwed to the wall. As mentioned many of these dimensions are not critical but in order for the loom to work well there are some important things to consider.


Size of the Largest Wire Facing?

The length of the two horizontal members of this frame, the cross-pieces, determines the longest laid wire that can be used and thus the length of the largest facing. For this loom I chose 42″. These cross-pieces could be made shorter (or longer) depending on the sizes of mould you intend to make.

The distance between the upper and lower cross-pieces limits the width of the largest facing. From its starting position (shown here by the upper red line) the bottom of the 4″ wide traveling beam can be lowered 29-3/4″ before it bumps the top of the lower cross-piece. This allows a wire facing width of about 29″ (after accounting for starting and finishing twists). Another important dimension that is built into this loom frame is shown by the green arrow (22-1/2″ long here) indicating an additional space that is sized to provide enough height for the weighted wires should the loom be used to its maximum 29″ width.


Sufficient Wire Length and Enough Space for It to Hang

When preparing to make a laid facing lengths of soft wire are hung over the lift rod and attached to weights at the bottom. These chain wires get twisted around the laid wires as these are added, one by one, and as the upper parts of the chain wires get more and more ‘squiggly’ the unused, straight parts below will seem to shrink, pulling the wire slides and attached weights gradually upward. This ‘mock-up’ (pictured in the next few photos) of the largest possible facing tries to show why it is important to take both the wire length and ‘shrinkage’ into account. The mock-up is limited to only two wires, one full length and the other shorter. This second, shorter wire is included just to show how much the first would have moved up had a 29″ facing actually been made here.

Based on experience I’ve found a standard calculation that works to figure raw chain wire length: width of facing times 2.5 plus 16″. This provides enough length without creating too much waste. The calculation for this (fictional) 29″ wide facing went like this: 29″ x 2.5 = 72.5″. 72.5″ + 16″ = 88.5″. After a piece of wire was cut to this length it was draped over the lift rod. The two ends were passed through the twisting mechanism and twisted together at the bottom of a wooden wire slide. With a weight attached it looks like the one ON THE LEFT above. You can see that the wire can’t be longer since the weight needs to swing free above the floor. This is how this weighted wire would look at the beginning BEFORE the addition of laid wires.

The shorter weighted wire ON THE RIGHT shows how the first one would look AFTER it had been ‘used up’ by twisting in enough laid wires to make a 29″ wide laid facing. The bottom would have risen a little over 7″ from its starting position.

Now the twisting mechanism has been cranked all the way down (as it would have been to finish this fictional super-wide facing). Even though the weight and wire slide have ‘risen’ about 7 inches there is still room beneath the spindles for the remaining wire to swing free as the last twists are added. (The weights, wire and wire slides all need to turn freely as twists are added.) This is important; you don’t ever want the bottom of the twisting mechanism to interfere with the top of the wire slide.

Another view of the waste wire that would be left in the wire slide. This is a good amount.


Locating Holes for the Lead Screw Bushings

The traveling beam is exactly 1″ thick and the lead screws should pass right up through its center…

…so the holes for the lead screws should be set exactly 1/2″ in front of the uprights. ‘A’ shows the plane established by the front surfaces of the two uprights. ‘B’ shows the center line of the lead screws (and the traveling beam). The upper part of each hole is drilled large enough to accept standard nylon bushings.

The lateral distance between these holes is figured out in a different way. Upper and lower crosspieces are virtually identical with holes spaced exactly the same.

To find this spacing a loop of roller chain is cut to get the twin chain sprockets very close to the preferred spacing. This would put them near the ends of the frame cross-pieces. (Unlike in the photo the linked sprockets and chain would simply be set out on any flat surface in order to do this. I may replace this photo when I have a better one.) The actual center-to-center distance is measured from the sprockets to determine how widely to space the holes drilled down through the cross-pieces. All four holes should be the same distance (left or right) from the center line of the loom. The chain should be a little loose. The two lead screws on this loom ended up just shy of 38-1/4″ on center.


A Place for the Lift Lever

Slots are cut in the frame to accommodate the lift lever. The exact placement isn’t too critical; it needs to be high enough for a weight to be attached to the far end as shown here. The weight serves to return the lever to its starting position when the treadle is released. The bottoms of these uprights are shaped and drilled so that a base can be attached if the loom needs to be free standing. This makes the loom somewhat portable, and able to be set up almost anywhere if needed.

#48 Mould Maker’s Loom Part 1

This series of posts should allow for a better understanding of how this loom works. This first post is an overview of the four basic parts of the loom; the frame, the wire lifting mechanism, the indexing mechanism and the chain wire twisting mechanism. Later posts will give more detail on each of these in turn.

Above, the loom complete, with all its mechanical parts attached. Other essential parts are added when the time comes to make a laid facing or backing. These include wire weights, wire spacers and wire slides.

The Frame

Here is the loom frame stripped of all of the moving parts which are normally attached to it. Two mechanical assemblies will be fastened directly to this frame; the lift mechanism and the laid wire indexing mechanism. The third mechanism, the one that twists the chain wires, is not attached directly to the frame. The loom is fastened to the wall in the photo. This takes up much less space than the free-standing option.

The Lift Mechanism

In the photo above only the lift mechanism is installed on the loom. In use it has a simple function; to lift the entire web of wire a short distance (1/2″) to make room for laid wires to be slid in at the bottom, one at a time. When the lifting mechanism is released the wire facing drops back down. The chain wires are then given a half twist to incorporate the new laid wire into the facing. This cycle is repeated hundreds of times to make a facing.

Above are shown the two positions of the lift mechanism, up and down. When the foot treadle is depressed (a brick supplies the force here just to demonstrate) the lifting beam at the top is raised by means of rope and pulleys. The middle of a length of rope passes under a lever which is attached to the treadle on the right. This creates a V shape with two upper ends. Each of these (rope) ends passes up and over the top of a wooden pulley, then down and through a metal pulley and back up to the very top of the loom where it is firmly attached. The inch or so that the rope is pulled down by depressing the treadle lifts the beam and all the wire and weights attached to it a half inch. The lift beam returns to the lower position when the treadle is released.

In both photos above the upper line (red) passes through the (fixed) axle of the wooden pulleys and the lower line passes through the axles of both steel pulleys (movable). Hopefully this makes it easier to see that the metal pulleys (and the beam they are attached to) move up and down when the treadle is depressed and released.

The motion may be easier to see in these two photos. Notice the smaller beam being lifted up from the angle iron which supports it. There’s only 1/2″ of movement and it’s hard to see in the photos so I’ve added arrows to show the gap.

The Indexing Mechanism

In this photo only the laid wire indexing mechanism is installed on the frame. The purpose of this assembly is to lower the chain wire twisting mechanism a precise distance for every laid wire added. The twisting mechanism will be bolted to the top edge of the horizontal ‘traveling beam’ by means of the five holes along the beam’s edge. Identical vertical lead screws are linked with sprockets and roller chain. When the crank at the top right is turned (CCW) the two screws will turn together and lower both ends of the beam the same amount. As laid wires are added the beam gradually ‘travels’ down, ending up near the bottom if a large facing is being made. A counting wheel attached to the top of the left hand lead screw makes it possible to precisely control how far the crank is turned each time. This is done by counting audible clicks as the pins of the counting wheel pass a pawl; the same number of clicks are counted out each time to produce uniformly spaced laid wires. There are many of these wheels, each with a different number of pins, so that a counting wheel can be selected to create a specific spacing.

The Wire Twisting Mechanism

In this photo the loom (with both previously discussed assemblies attached) is ready to receive the twisting mechanism which will be bolted to the traveling beam. The twisting mechanism is self contained and activated by a hand crank at its right hand end. The whole thing moves gradually down the frame of the loom as the wire facing grows larger.

The twisting mechanism is composed of many parts. Above are shown five ‘spindle racks’; a separate one must be made for each different chain wire spacing. Each of these provides the main structure for the mechanism. All of the moving parts are interchangeable and are only installed to complete the spindle rack that is currently in place on the loom. After it is bolted to the traveling beam of the loom and completed the mechanism functions to add twists to the chain wires. The crank twists all chain wires simultaneously. The twisting mechanism is the most complicated part of the loom and will have its own post; probably the last.

The Complete Loom

Once again, the complete loom, with all of the mechanical assemblies attached.