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2.5. The ball hinge emulation

The universal rest with the ball hinge is the best equipment for setting a bolster or a flat pillow. However its main assembly (the ball hinge) quite often is not available in domestic workshop. In that case the main unit can be emulated with own plate for every plane of controlling.

This idea many years is realized in devices for navigation of ships, airplanes, rockets, space vehicles. The device named “gyroscope” creates a bearing coordinate system on a moving object. The authors of the book naturally came to the same idea after testing numerous rests.

Despite of very “scientific” name the “gyroscope platform” can be domestic made of wood details. Drafts of a rest emulating the ball hinge were shown on the site klk.pp.ru at Russian lace maker’s request in 2006.

The rest contains three movable platforms. The first (lower) platform rotates on a table. The second (middle) platform is set on the thirst one and rotates at two pin axes. The third (upper) platform is set on the middle platform as well on two pin axes (Fig.2.38).

Fig.2.38. The rest for small bolsters

The tray for the bolster is attached to the upper platform. The bolster is plunged into the tray down to 0.3 … 0.4 of its radius. This depth is enough to fix the bolster without any additional contrivances. Variants of the rest are ahown on Fig.2.39, Fig.2.40.

Fig.2.39. The rest for small bolsrters

Fig.2.40. The rest emulating the ball hinge

The details of braking on heel and elevation angles are not shown. Brakes are fulfilled as metal sectors with soft plastic gaskets. Braking effect is achieved by squeezing sectors with screw-nut. The same effect would be created with an off-center device. It is desirable that bolster controlling would be pedal. Steadiness of rest is ensured with frames or skis attached to tables.

2.6. Rests for flat pillows

Lace makers in west Europe and north America prefer to set patterns on wide flat pillows instead bolsters that are so popular in Eastern countries. In western lace making technique a pillow stays practically immovable. It makes possible to held the pillow on knees and use the simplest contrivances to fix its incline (Fig.2.41).

Fig.2.41. Support for a flat pillow

Nevertheless a flat pillow as well must have three degrees of freedom to deliver the following manipulations with pillow:

- rotating around the center of a pillow;

- inclining towards a lace maker;

- lifting a pillow along vertical axe.

That is why rests are invented for flat rests too. A study table and dinner one is inconvenient as rest since it is immovable in the room. It would be better if a lace maker had an independent rest for the pillow. Such a tool naturally could be set at the best illuminated place of the room.

Examples of pillow rests are shown in books [4] and in the WWW. They origin out of two prototypes:

- racks (”horse”, “goat”) having four leg;

- reading (music) stands having one leg.

A designer of the rack (Fig.2.42) created a hard and steady rest.

Fig.2.42. “Goat” for flat pillows

An author of the “music-stand” (Fig.2.43) seems to make an elegant rest; staying aside steadiness of the device.

Fig.2.43. “Music-stand” for flat pillows

During experiments with equipment for lace making authors of the book made a rest for a disk pillows too. It is alike the known construction (Fig.2.44).

Fig.2.44. A steady rest for disk pillows

The author’s model (Fig.2.45, Fig.2.46, Fig.2.47) provides two regulations:

- shift at 60 … 80 cm (24 … 32 inches) along vertical;

- incline at 0 … 60⁰.

Fig.2.45. Author’s rest for disk pillows

Fig.2.46. Units of the rest

Fig.2.47. Mushroom pillow on the rest

The bearing post moves between two flats. The height of a disk is fixed by means of squeezing the flats. The incline of a disk provides a hinge braked with a rubber washer. The steadiness of the rest is guaranteed by size of platform. There is enough room for lace maker’s feet. The bearing post is fastened with three inclined flats.

3. EQUIPMENT FOR PREPARATION OF THREAD FOR LACE MAKING

3.1. The techniques of thread untwisting

Modern Russian laces are plaited of different threads according to local traditions in provinces. There are bleached and unbleached linen, silk, artificial (synthetical) fibre, cotton thread (”moulinet”), rarely - woolen and metallized thread.

The high quality laces technique demands the finest thread. When fine thread is not available, lace makers are to untwist “moulinet” (Fig.3.1).

Fig.3.1. A clew, “moulinet” and bobbins

The untwisting technique is extremely labor-intensive in domestic conditions. The authors of the book attempted to find own means to solve the problem. Process of “moulinet” untwisting is dismembered at three consecutive operations:

- winding of thread out of a skein to an intermediate clew;

- untwisting of “moulinet” out of the clew at three doubled threads and winding each of them around intermediate spool;

- rewinding of the thread out of the intermediate spool to a reel that keeps the thread up to the moment of plaiting (winding on lace bobbin).

Authors made contrivances for each of the operations mentioned above.

3.2. The contrivance for rewinding of thread
out of skein to the clew

An advance notice is to be said: the operation is so simple that it can be done with a tool made of materials at hand. Such contrivance is named usually as “a small cunning”. For instance one can take a plastic bottle approximately 10 cm (4 inches) in diameter with a cone neck.

The skein is to be put on the neck of the bottle filled with water to enlarge the mass that makes the bottle to be steady. The easy skein rotates around the bottle neck when thread is rewound around the clew. Of course one can feel the winding uncomfortable because of primitiveness of the tool but the goal is achieved tolerably.

The more skilful master can make a specialized tool for rewinding that eliminates grave shortcomings of the “bottle construction”. It is recommended to use a spool of a spinning rod. The spool with 10 cm (4 inches) in diameter is set on a ball bearing (Fig.3.2).

Fig.3.2. Spool for a spinning

Thread is rewound easily without entangling. It remains only to fasten the spool to a platform or to the table with a screw-clamp.

At last one can cease looking for ready devices that are made for solving other technical tasks. It may be more productive to design a device intended for rewinding exclusively. Such a device must have small friction of rotation and adaptation to changing of skein size. It is proves to be possible to realize the tool even in domestic workshop.

The contrivance for rewinding of thread from the skein to the clew is shown on the cinematic scheme (Fig.3.3).

Fig.3.3. Rewinding of thread out of skein to the clew

The vertical axe of the disk plate 1 is fastened to the ball bearing 2. Four wedges 3 are set on the plate 1 along radius with step 90 grades. The wedges slide on the plate surface when the thrust plate 4 moves upwards and downwards. Every wedge has a ledge at the external side.

The ledges are intended for packing of the skein 5. The wedges take position in accordance with skein sizes. Plate 1 and wedges rotate together with the skein when thread is rewound.

Two important features of the device are not shown on Fig.3.3:

1. The wedges are tightened with springs toward the axe of gyration.

2. The thrust plate 4 is fixed in position according to the skein diameter. When fixation is released, the plate 4 are pushed upwards with the wedges which moves toward the gyration axe. As a result the distance L between external sides of the wedges shortens.

Every wedge has a cover plastic plate having mirror surface to weaken friction between the wedge and the plate 4.

The rewinding device is shown on the photo (Fig.3.4). It is fulfilled as an autonomous unit that can be set apart or can be mounted together with other tools on the working place.

Fig.3.4. The device for rewinding of “moulinet”
out of the skein to the clew

Details of the device are made of accessible materials. For the plates 1 and 4 is used plywood. The wedges are cut of wood flats. Guides for them are made of aluminum profile. The gyration axe is substituted with four short pillars mounted into the plastic body of the roller (a detail of skate board). Two ball bearings are pressed into the roller.

3.3. The contrivance for untwisting of thread

The “moulinet” is twisted of 6 or 12 cotton threads. More thin threads are needed for lace making. They can be made by splitting (untwisting) the “moulinet”.

Manual untwisting does not prove to be simple as it seems at first sight. It becomes just clear that an operator ought to have the third and fourth hands. In other words this work can not be done without an assistant.

Splitting technique consists of three operations:

- pull out of the clew a part of “mouline”, untwist it and split at three flows of two-, three- or four-fold thread;

- rewind split threads around three intermediate spools keeping equal tension;

- stop splitting every time when the next part of “moulinet” is being pull out of the clew.

It ought to keep strictly the rule - avoid excessive touching the thread by fingers to save its cleanness.

The problem of keeping thread tension constant arises because of growing difference in length of untwisted threads. The greater is difference, the less is tension. The state of emergency takes place. One must stop splitting and eliminate thread sag in the emergence channel by means of additional rotation of the spool. Of course it is impossible in this case to avoid needless touching the thread.

Authors of the book suggest method of splitting that provides automatic compensation of thread sag using gravity strength. The principle can be seen on the cinematic scheme (Fig.3.5).

Fig.3.5. Compensation of thread sag

Mass of the clew 1 is enlarged up to 150 grams (0.33 pound) with a metallic ball inserted into it. The clew works as a plumb. It hangs at pulled out thread (L » 1.5 meter or L » 5 foots) and rotates untwisting the “moulinet”.

The comb 2 splits the “moulinet” at three threads. The split thread moves towards the comb 3 going under the roller 4 that is pulled down with gravity strength F₁.

The split thread moves farther above roller 5 and under roller 6, both being set on the disk 7. The gravity strength F₂ turns the disk 7 clockwise.

It is to be noticed that using two different compensators 4 and 7 is not obligatory. The matter is both realize the same principle. On this reason it would be possible to change the disk compensator 7 with falling roller like the roller 4. However author saved both compensators as they are to demonstrate possible variants of tension controlling.

After the roller 6 the split thread goes through a guiding comb 8 to the intermediate spool 9 set on the main roller which is rotated by hand of an operator i.e. a lace maker.

If tensions of three threads are equal, the balance of all strengths (gravity and friction) takes place. The roller 4 moves up to level of the combs 2 and 3; centers of the rollers 6 and 7 are at the horizontal line.

As soon as one of three threads becomes longer then other two, thread tension relaxes and the balance of strengths comes at other position of rollers. The roller 4 falls and the disk 7 turns clockwise. Movement of rollers stops when tension restores at this channel and becomes equal tension in other channels.

When the current piece of the “moulinet” is split, it is necessary to stop movement of disks 7 and spools 9. The pause is needed to pull the next “moulinet” piece out of the clew 1 and to untwist it.

There are many methods to work out a cinematic scheme according to the compensation principle. One of methods is presented on Fig.3.6 (front view) and Fig.3.7 (plan view).

Fig.3.6. The contrivance for untwisting of “moulinet”. Plan view

Fig.3.7. The contrivance for untwisting of “moulinet”. Side view

All basic units are seen on Fig.3.6 including:
- the main shaft with three spools and the fly-wheel;
- the reducer (on the left from the shaft);
- the eccentric mechanism and three guiding forks;
- three disk compensators and the brake lath in front of the disks;
- the frame and two combs on it;
- three lever compensators that can be seen through the frame;
- the box intended to save the clew; besides the clew there are three spools saving the split thread.
Fig.3.7 shows the following units:
- the brake of the fly-wheel;
- the lever compensators under the combs;
- the levers tied to the disk compensators with the cords