Abstract: A mesh cloth, which does not bring about clogging and has uniform openings throughout the whole surface, and a screen-formed plated article, which can be stably used as a printing screen and a cylinder for rotary printing, and is useful as an electromagnetic wave shielding material and a shadow mask. The mesh cloth is produced by using a core-sheath composite filament using a sheath comprising a component having a lower melting point than a core. A metal plating is applied on the mesh cloth, in which the core threads of the crossing threads at the point of intersection of the crossing threads are adhered to each other by melting the sheath component, the surface thereof is uniformly covered with the sheath component of the crossing threads, and the thickness of the cloth at the point of intersection is from 85 to 60% of the total thickness of the diameters of the crossing threads.

Abstract: A system for forming artistic ink impressions. A case stores ink stamping accessories and/or allows large surface area stamps to be used.

Abstract: A lip stencil plate for placing stencils on a user's lips. The lip stencil plate includes a stencil panel for placing against a user's face. The stencil panel has an inner surface and an outer surface. The outer surface is convex and the inner surface is concave for placement against the face of a user. A plurality of bores through the panel are used for stenciling.

Abstract: A stencil for a printer used to print a substance onto a substrate using a blade that passes over the stencil during printing. In embodiments of the invention, the stencil includes a first section having a first printing pattern formed thereon, a second section having a second printing pattern formed thereon, a seam between the first section and the second section, and a strip that covers at least a portion of the seam to allow the blade to pass smoothly over the seam.

Abstract: A method of preparing a plastic mask for paste printing with a plastic sheet being provided with an area containing a predetermined pattern including one or more through-holes is carried out by the steps of bringing the plastic mask provided with electroconductive material on at least one surface into close contact with a printing material while applying an electrical ground potential to the electroconductive material and then using the mask for paste printing by spreading and pressing a past to cause it to pass through any of the through-holes forming the predetermined pattern for deposit on the printing material and then removing the mask from the printing material to leave the paste printing pattern.

Abstract: A re-useable stencil kit made of a semi-rigid panel material for the application of painted address characters and a decorative painted background on a street curb. A base decorative background stencil (10) having an elongated opening featuring a decorative shape (12, 28) at the right and left sides of the opening. Address characters formed in separate, character stencil cards (18) featuring one address character (20) each, are arranged within the cavity of the opening in the background stencil along with blank spacer cards (22, 24, 26) to form the desired address. The spacer cards fill in void space on either side of, and center the character stencil cards, simultaneously masking the painted background. The stencils and spacers fit closely together to prevent paint over spray and to provide accurate character alignment.

Abstract: A stencil printer of the present invention includes at least one ink drum for wrapping a master around its outer periphery. An ink feed device feeds ink to the master wrapped around the ink drum. A pressing member is movable into and out of contact with the ink drum at a position where it faces the ink feed device. An image is printed on a paper fed from a paper feed section at a print section where the ink drum and pressing member face each other. A belt conveyor includes a belt extending between the paper feed section located upstream of the print section in the direction of paper conveyance and a paper discharge section located downstream of the print section in the same direction through the print section. The belt conveys the paper fed from the paper feed section while causing it to electrostatically adhere thereto. The paper is sufficiently electrostatically adhered to the belt before it reaches the print section, so that air suction, an air knife, a separator or the like is not necessary.

Abstract: A stencil and stencil identification system in which the stencil carries a tagging device capable of storing data corresponding to characteristics of the stencil and the pattern of apertures formed in the stencil. The stencil with tagging device may be utilized in combination with a stencil printing device having a tag reader which reads information data stored within the tagging device and/or writes information into the tagging device relating to characteristics of the stencil or other criteria.

Abstract: The positioning of mesh side features in a stencil mask are controlled to produce a mask which possesses high structural integrity and which exhibits a low service life. Mesh side feature control also eliminates certain unnecessary design side channels and mesh side via openings. Mesh side feature placement at T-shaped design side junctions is also controlled to produce a more uniform distribution of material which is screened through the stencil mask.

Abstract: A multi-layer stencil is disclosed for applying solder paste to a printed circuit board. The stencil is formed from first and second layers of stencil material, e.g., stainless steel sheet, the second layer overlying the first layer in selected areas thereby forming a region of increased stencil thickness in those areas. A first plurality of apertures is defined through the thickness of the first layer only and a second plurality of apertures is defined through the combined thickness of the first and second layers in the selected regions. This type of multilevel stencil is useful for depositing differing thicknesses of solder paste onto a circuit board comprising a hybrid of through-hole and SMT devices.

Abstract: Solder paste is deposited using a solder stencil with an aperture having a concave edge in order to reduce the formation of solder balls. The solder deposit may be formed on a pad such that the paste has a concave edge. Solder paste deposits may be made on adjacent pads with the concave surfaces facing one another.

Abstract: A regenerable stencil printing plate is provided, which can be repeatedly used in master making and printing. The stencil printing plate comprises a film made of such a polymeric material as polypyrrole and polythiophene which shrinks when it adsorbs a specific compound, and numerous fine apertures are formed in the film in cross sectional direction thereof. Stencil printing is performed by providing the stencil printing plate as mentioned above, transferring the compound to the film in such a manner that a desired image is reproduced to expand the apertures selectively at sites to which the compound is transferred, and allowing an image forming material to pass through the thus expanded apertures and transfer to a recording medium. The stencil printing plate can constitute an outer circumferentical surface of an ink-permeable cylindrical printing drum used in a conventional stencil printing apparatus.

Abstract: A stencil for use in fabricating semiconductor devices is disclosed that has an aperture having a first portion extending from a first side thereof and a second portion extending from a second side thereof to minimize the shear stress between the material extruded therethrough and the stencil. The stencil allows for material to be extruded through the top of the stencil to the surface of the substrate and not contact the wall of the second portion of the aperture of the stencil. Since the material only contacts a small area of the first portion of the aperture near the top of the stencil, the material remains on the substrate and not in the aperture of the stencil.

Abstract: A printing screen assembly is provided with an integral shield to protect the ink which is dispensed on the top surface of the screen during the printing process. The mesh material is mounted on a frame member and coated with exposed emulsion with open areas for transferring ink to a glass substrate. A shield is mounted on a second frame member and positioned on the first frame member so that the shield is placed in parallel spaced-apart relationship with the mesh material. The frame members, the mesh material and the shield form an enclosed ink containment area to protect the ink from contamination during the printing process. For water-based ink, water vapor can be added to the containment area to maintain the ink at the desired relative humidity. An ink dispensing strip fits in the containment area between the shield and the mesh fabric of the screen.

Abstract: A dual track stencil system includes a first set of rails and a second set of rails, each of the rails being independently controlled for allowing for independent movement of circuit boards through the stencil system for processing. The stencil system includes a working area at which the circuit boards are stenciled and includes a stencil having two patterns formed thereon. In one embodiment, the stencil system includes a solder dispensing system for dispensing solder paste onto the stencil.

Abstract: A method of fabricating a plastic mask for paste printing with a plastic sheet being irradiated with an excimer laser beam for forming at least one penetrating opening containing area including at least one through-hole in the plastic sheet is carried out by the steps of bringing a polymer film capable of absorbing at least part of the excimer laser beam into close contact with a back surface of the plastic sheet which is opposite to an excimer laser beam irradiation side thereof which is to be irradiated with the excimer laser beam; forming at least one penetrating opening containing area including at least one through-hole in the plastic sheet by irradiating the excimer laser beam irradiation side thereof with the excimer laser beam; and removing the polymer film from the plastic sheet after the formation of the penetrating opening containing area. By use of a plastic mask fabricated by the above method, a paste printing is also carried out.

Abstract: A stencil printing machine includes a main body; a covering openably attached to a surface of the main body and enclosing a space between the main body and the covering for storing a printing sheet and a stencil sheet therein; a flexible sheet attached to the covering so as to face the stencil sheet; a pressure reducing device disposed under the main body so as to communicate with the space and reducing pressure in the space; and a manual operating device for operating the pressure reducing device when being pressed downwardly from an operation start position that is substantially in the same level as the covering.

Abstract: A tensioning frame (1) for stencils (9) formed of metal foils or plastic films, especially for stencil printing, provided at their margins (8) with perforations (10) for tensioning. The frame includes a tensioning device operated by a pressure medium for driving tensioning bars (5) that carry hooking pins (6) that engage the perforations of the stencil. The tensioning device is formed by an elastically deformable tensioning tube (4) disposed in a frame profile (2) and uniformly supplied with a pressure medium. The tensioning bars lie with the full length of their front sides in contact with the tensioning tube and with their back sides resting against fulcrum nubs (17) which in turn are supported against an extrusion (3) which closes the frame profile. The tensioning bars can be pivoted by inflating and expanding the tensioning tubes to stretch the stencil over a bridge (16) on the frame.

Abstract: A method of screen printing on to a hard non-absorbent substrate (1) involves using a screen (10) which has an ink permeable area (B) whose pattern corresponds to whatever is to be printed. The area B is divided into two parts (X and Y). Part X is of normal, maximum, ink carrying capacity and part Y is of reduced ink carrying capacity. The ink carrying capacity of the reduced ink carrying capacity part Yis determined by the extent to which it is coated with ink/impenetrable emulsion (20), the size of the pores (18) in the screen (10) and the type of ink used. The ink carrying capacity of the part Y reduces with distance away from part X. The emulsion coating (20) may be in the form of dots (200), with the dots (200) increasing in diameter with distance away from part X. During printing, the reduced ink carrying capacity part Y is located over the edge region (E) of the substrate (1), and the substrate is printed up to but not on to its edge (6).

Abstract: Solder paste is deposited using a solder stencil with an aperture having a concave edge in order to reduce the formation of solder balls. The solder deposit may be formed on a pad such that the paste has a concave edge. Solder paste deposits may be made on adjacent pads with the concave surfaces facing one another.

Abstract: An alignment aid for golfers consisting of a rigid hemispherically shaped body having two intersecting slits therein for making a mark on a golf ball which indicates the intended path of the golf ball and the preferred orientation of the club face for obtaining the intended path of the golf ball.

Abstract: A stencil sheet unit includes a stencil sheet having a rectangular area and a mount paper substantially equal in configuration to the stencil sheet, wherein the stencil sheet is adhered in part onto the mount paper by an adhesive portion provided between the stencil sheet and the mount paper, wherein an area of the adhesive portion is smaller than half of the rectangular area of the stencil sheet, and a printing-preparation is made on a portion other than the adhesive portion of the stencil sheet.

Abstract: A foil screen is held in registration with a printed circuit board during the application of solder paste on the printed circuit board, within a frame assembly with a prescribed tension by providing a rigid frame for juxtaposition with the foil screen, engaging the foil screen with at least one coupler, engaging the one coupler with a tensioner for resiliently biasing the one coupler to exert a tensioning force of prescribed magnitude upon the foil screen to tension the foil screen with the prescribed tension, and selectively applying an actuating force to the one coupler, the actuating force being opposite to the tensioning force, and selectively releasing the actuating force from the one coupler, such that upon actuation of the actuator to apply the actuating force, the tensioning force is overcome for release of the foil screen from the one coupler, and upon actuation of the actuator to release the actuating force, the one tensioner resiliently biases the one coupler to exert the tensioning force of prescr

Abstract: A stencil of sheet metal for enabling solder paste to be applied to circuit boards includes a main body portion and opposite side regions which are apertured so as to be more flexible than the main body portion, and so as to enable these opposite side regions to be bent without kinking or other deformation during tensioning. The invention further includes an apparatus for enabling solder paste to be applied to a circuit board by a stenciling process, the apparatus including a stencil as described together with a support therefor, the stencil being attached to the support and being detachable therefrom. The side regions of the stencil are flexed for attachment to the support, so that the interconnection between the support and the stencil does not project beneath a lowermost planar surface of the stencil.

Abstract: A disposable screen used in a screen printing system for printing onto electronic devices is formed of a non-metallic material. The screen is patterned from a foil. The material can be selected from a group consisting of plastic, nylon, paper, and resin. A disposable screen is mounted in the screen printing system, after which a paste material (including solder or an adhesive such as polyimide, bismaleimide, or a thermoset or thermoplastic compound) can be printed through the screen to a target structure. The used screen is discarded after one or more uses and a new screen is mounted in the screen printing system. A teaching sheet having a disposable transparent film is also used to set up the screen printing system. The film is detachably attached to a frame. After one or more prints, the used film is detached and replaced with a new film.

Abstract: An engraved recess (4) is formed in a resin stencil (1) at a position on a surface of the resin stencil where the resin stencil, when registered with a circuit board, agrees with a fiducial mark of the circuit board. The recess is formed by a laser (3) and serves as a fiducial mark.

Abstract: In order to improve a stencil holder for stencils made of metal films, preferably for screen printing, comprising a frame, at least two stencil receiving means arranged on the frame and detachably holding the stencil and a stencil tensioning device, with which the stencil can be tensioned in at least a first tensioning direction, such that the stencil can be tensioned as evenly as possible, it is suggested that the stencil have holding strips extending on from a stencil section, that these holding strips extend at the most over the respective length of an edge of the stencil section in the respective longitudinal direction thereof, that each holding strip be detachably securable on a respective stencil receiving means and that the stencil be tensionable in a first tensioning direction and a second tensioning direction extending transversely to the first by means of the stencil tensioning device acting on the stencil receiving means.

Abstract: A heat-sensitive stencil sheet, and a method and a composition for perforating the same are provided, in which photothermal conversion materials transferred to the stencil sheet do not blur or spread but are fixed thereon faithfully to desired images, and clear images are printed. The heat-sensitive stencil sheet has on a side thereof a liquid absorbing layer to which the photothermal conversion material is to be transferred, and the liquid absorbing layer comprises a hydrophilic resin and a water-repellent compound, and optionally organic and/or inorganic particulates. The hydrophilic resin and the water-repellent compound may be mixed at a proportion sufficient to provide a contact angle of 20 to 150 degrees between the liquid absorbing layer and the liquid. The liquid, in which the photothermal conversion material is contained, can comprise water and/or a hydrophilic solvent. The liquid absorbing layer preferably has a softening or melting point of 40 to 120.degree. C. and has a thickness of 0.01 to 20 .

Abstract: A material deposition contact mask is disclosed in which apertures formed therein have a larger dimension in lower openings in a bottom side of the mask contacting the substrate than in constricted openings located near the top side of the mask. Apertures of the contact mask have knife edges located within the upper sidewalls thereof, e.g. within the top 25% of the mask thickness above the substrate. A mask is disclosed which, in addition, is thermally compensated to the substrate temperature at which the deposition is performed. Methods for fabricating the mask by differential etching are disclosed.

Abstract: A drum and an ink holding member for a stencil printer and capable of obviating offset effectively, and a stencil highly resistive to printing are disclosed. The ink holding member constitutes the outer periphery of the drum and allows the stencil or master to be wrapped therearound. The ink holding member is implemented as a sintered sheet of fibers. At least the surfaces of the fibers are constituted by metal.

Abstract: There is disclosed herein a self-shearing stencil for use in applying solder paste or other bonding material atop a printed circuit board (PCB) in a predefined pattern. The stencil 50 has a top surface 12, a bottom surface 14, a first surface cavity 16 in the top surface, and a second surface cavity 18 in the bottom surface proximate the first surface. The cavities 16/18 overlap in a predefined manner so as to be in open communication with each other. When the stencil is placed on the PCB, the cavities are filled with solder paste and the PCB is then lowered away from the stencil, whereupon a bottom ledge 26 (defined by the stencil material underneath the first cavity) shears off the solder paste in the first cavity from the paste in the second cavity.

Abstract: A printing drum of a stencil printing machine is formed of a base member having two annular members spaced apart from each other and a transverse bar connecting the two annular members; a flexible multi-porous sheet having a filled portion at at least a part of a peripheral portion except a central portion thereof and being wrapped into a cylindrical shape around the outer peripheral surface of the base member, and around which a stencil sheet is wrapped; a spring member situated between one end of the flexible sheet and the base member to attach the flexible sheet resiliently on the base member; a stencil clamping device provided on the transverse bar for selectively clamping one end part of the stencil sheet; and an inner pressing device situated inside the flexible sheet for supplying ink outwardly. The inner pressing device pushes the flexible sheet radially outwardly when the base member and flexible sheet assembly rotates.

Abstract: A method for applying solder paste on tape carrier package component sites of a printed circuit board is disclosed. In accordance with a method and system of the present invention, a stencil having multiple openings for each device pad on the printed circuit board is provided. Each of the openings is approximately 0.012".times.0.0053" in size. The stencil is then secured in a fixed position directly above a printed circuit board. Finally, solder paste is selectively applied to the printed circuit board through the stencil with an applicator.

Abstract: A frame is disclosed for stretching a printing screen quickly and with uniform application of tension to the screen. The frame includes a base portion that defines a stretching plane in which the workpiece is stretched. A swingable portion of the frame pivots relative to the base and moves from a relaxed position in which the swingable portion defines a plane that intersects the stretching plane, to a stretching position in which the swingable portion is fixed in the stretching plane. A retainer secures the edges of the screen to the frame such that the screen mesh is uniformly stretched as the swingable portion is pushed into the stretching plane. A tension cable extends through the frame over a series of pulleys spaced several locations through each leg of the frame. Increased tension on the cable pulls the swingable portion of the frame into the stretching plane and holds the frame in that position to maintain tension on the screen.

Abstract: A differential thickness stencil (14') integrally formed from two sieves (601 and 602) having different thicknesses (701 and 702) for a two-stage solder printing process for printing the solder mask for a fine-pitch component alongside that of a larger component. The differential thickness stencil (14') includes a first sieve (602) having at least one through-hole (142) of a first height (702) from a top surface portion (722) of the stencil to the bottom surface (714) of the stencil. This first sieve (702) has at least one inverted well (742) having an opening on the bottom surface (744) and having a second height (746) lower than the first height (702) starting from the bottom surface (714) to an underside ceiling (746) of the top surface of the stencil.

Abstract: Printing screens are registered using a photosensitive position locating sensor which is affixed to a pallet and aligned with the image of a register mark on the first of a series of printing screens. The location of the image is stored and signalled in a display device. The pallet is then roughly aligned with a second and subsequent screens of the series. The subsequent screens are each moved until the display image of its register mark is superimposed upon the stored image. The signal output from the sensor is applied to a microprocessor which controls the display device.

Abstract: An arrangement to prevent loosening of a stencil which is wound round a core in the shape of a roll. The stencil roll has at least one side surface thereof applied with a paste. This is effective in preventing the stencil from becoming loose by an inertia force of the stencil roll when it is unstable during its rotation. Thus, the stencil can be paid out from the stencil roll without becoming slack.

Abstract: A mask stencil (112) is made with at least one indicator line (204, 205) of material pre-removed from a wear surface (212) of the mask stencil, the depth of the line is approximately the amount of stencil mask material that can be worn from the wear surface of the mask stencil by a squeegee (110) without adversely affect an amount of solder paste (114) that accumulates on a printed circuit board substrate (116) through openings (201) in the mask stencil. In another embodiment, the mask stencil (112) is made with at least one indicator line (304, 305) of material pre-removed from a surface opposite (314) the wear surface (312). The amount of stencil mask material that remains above the indicator line is approximately equal to the amount of material that can be worn from the wear surface of the mask stencil by the squeegee without adversely affect an amount of solder paste that accumulates on the printed circuit board.

Abstract: A cartridge squeegee head for solder paste machines. A squeegee blade is fixed to a coupling block. The coupling block is characterized by a coupling slot formed therein. The coupling block pivots and puts the squeegee blade into a print stroke position. The squeegee blade is then driven across the stencil foil surface.

Abstract: An method and apparatus for forming adhesive and solder pads on a printed circuit board to surface mount electrical components to the board. In accordance with an embodiment of the invention, a solder paste is deposited onto the printed circuit board through a first stencil that has a plurality of first openings. The solder paste forms a plurality of solder pads on the board. A second stencil is then positioned on the printed circuit board. The second stencil has a plurality of second openings, and a recess in its bottom face configured to receive the plurality of solder pads. After the second stencil is positioned on the printed circuit board so that the solder pads are received in the recess on the bottom face of the second stencil, an adhesive material is deposited onto the board through the second openings of the second stencil to form a plurality of adhesive pads on the board.

Abstract: A drum, stencil and ink holding member for a stencil printer are disclosed. The stencil is made up of a porous substrate and a thermoplastic resin film. The side of the substrate contacting the film has a surface roughness of 5 .mu.m Rz to 45 .mu.m Rz, preferably 5 .mu.m Rz to 35 .mu.m Rz or more preferably 5 .mu.m Rz to 25 .mu.m Rz.

Abstract: A method of forming a fiducial in a stencil for screen printing and the stencil so formed is described. A target fiducial thru-hole of a first size is formed in the stencil, the surface of the stencil in an area around and larger than the size of the target thru-hole is electrochemically etched, and the target fiducial thru-hole is filled with a filling material. The target fiducial thru-hole, included as part of the stencil pattern, is used as a target to which the fiducial mask, used in the electrochemical etching, can be aligned to. The target fiducial thru-hole may be made smaller than previously feasible because the fiducial is electrochemically etched, which means that it cannot fall out of the stencil. The filling in the target fiducial thru-hole is less likely to fail since it has a drastically decreased surface area to wall thickness area ratio compared to conventionally formed fiducials.

Abstract: A stencil sheet having a solvent-soluble resin layer is made by a plate-making apparatus, which is formed of a holding and moving device to hold and move the stencil sheet, a solvent supply device for supplying a solvent to the stencil sheet, and a control device. The solvent supply device is disposed at a predetermined distance away from the stencil sheet held by the holding and moving device and is moved with respect to the stencil sheet at least one of a horizontal scanning direction and a vertical scanning direction intersecting with each other. The control device obtains image signals of an image to be produced on the stencil sheet and controls the solvent supply device so that an amount of the solvent to be fed to the stencil sheet by the solvent supply device is changed based on the image signals to thereby perforate holes in the stencil sheet. The sizes of the holes perforated by the solvent is changed by the amount thereof to alter gradation of the image.

Abstract: A screen printing apparatus for printing a printing material to the front surface of a work that has a protrusion portion, comprising a stage for mounting the work, a screen frame formed on the upper surface of the stage, a screen mask secured to the screen frame, the screen mask having an opening portion at a particular printing position and a protrusion portion that covers the protrusion portion of the work, and a squeegee member moving in a particular direction for squeezing the printing material on the screen mask to the opening portion of the screen mask. In addition, the side surfaces of the protrusion portion of the screen mask are inclined to the main front surface for 90 degree or less. The portion that contacts the protrusion portion and the portion that does not contact the protrusion portion are separated by a slit.

Abstract: This invention is aimed at achieving a high-tension combination stretch screen. First, a print screen-mesh is bonded to a supporting screen-mesh at a bonding area. Then a portion of the supporting screen-mesh overlapping the print screen-mesh is removed. Then a new supporting screen-mesh is bonded to the bonding area, and again, a portion of the supporting screen-mesh overlapping the print screen-mesh is removed. Doubly fixed supporting screen meshes thus provide sufficiently increased tension to the print screen-mesh.

Abstract: An integrated circuit (IC) package includes solder paste inter-layer and alignment apparatus 100 for applying and aligning solder paste 150 with corresponding solder pads 160 on the IC package carrier 200. The apparatus 100 includes a thin layer 100 which is composed of high-temperature-resistant, non-solder-wetting, and electrical-insulating materials. The apparatus further has a plurality of apertures 110, each disposed on and penetrating through the thin layer 100 for applying solder paste 150 therein and for aligning with the corresponding solder pads 160 on the IC package carrier 200. The apparatus 100 further includes a removable thin film tape 120 disposed on a bottom surface of the thin layer 100 for temporarily maintaining the solder paste 150 in the plurality of apertures 110.

Abstract: A print pattern is formed on a glass plate 1 by using a screen plate in which a second ink-permeable region 7 having a lower ink-permeating rate than a first ink-permeable region 4 is formed in a screen region which corresponds to a space between the flat edge portion of the first ink-permeable region 4 and the outer end portion of the glass plate 1, whereby the formation of a locally raised portion in the film formed by printing at its end portion is avoided, and a decorative print is formed by a simple method without leaving a space in a flat end portion of the glass plate.

Abstract: A stencil for applying solder paste in a desired pattern for mounting electronic components on a surface of a circuit board, said stencil including a sheet having holes therethrough in a pattern corresponding to the desired pattern, a smooth upper surface for receiving the solder paste thereon, and a smooth lower surface for contacting the surface of the circuit board, the upper surface having relieved portions so as to increase the friction between the upper surface and the solder paste being squeegeed thereover.

Abstract: A stencil printing sheet and a process for perforating the same. The stencil printing sheet is perforated by using a solvent-soluble resin in the range of 0.1-100 .mu.m in thickness with a solvent which has a solubility of 100 seconds or less and a viscosity of solution of 1000 cps or less at 20.degree. C.

Abstract: The carrier of the screen printing stencil is mounted onto an auxiliary frame which holds the entire structure stable in the shape of a plate. Due to specific design of the longitudinal profile bars of the frame as bendible metal profile bars which return on their own into the outstretched shape, made e.g. of a springy sheet metal, a cylinder can be shaped from the relatively stable plate at any time.