US 2814080 A
Description (OCR text may contain errors)
NOV- 26, 1957 I s. w. 'rvoRlK 'a1-AL 2,814,080
` DRY WALL TAPE Y Filed Jan. 50. 1956 Y United States Patent O "ice DRY WALL TAPE i j Stephen W. T-vorik and Andrew liranni'tzer,
Cleveland, Ohio pplicanxanuary s0, 1956, serial No. 562,059
4claims. (cmo- 92) ldeal tl'iexjo'int-v and anyf' defects inthe material. Thev common material used in closingV the jointsV is paper tape appliedlwith cement. n The cement and paper seal the crevices'aidI unevenness and form a smooth continuation of the surface* ofthe' Wallwh'eniiistalled properly. However, man3/defects later appear in the work as a result of d'r'yingf th'ecement ande'dgies of the panels.
i y; The sheets-p ofplasterboardare often times damaged at tli'efedgs which results in al recess which must be iilleu the cement, covered with theV tape, and recemented teflobtaina-snri'ootiiVl wall surface. In applyingI the tape itis'fi'r'st cveredwith a` cement, after the tape has been placed over the jointi or defect being covered. A broad knife having-a blade,y of considerable width is 'drawn1 over the tape in" order to remove the excess cement beneath the tape whereupon the seams are left to dry and additional coats of cement are applied as required to achieve a smooth, uniform surface. 'After the dry wall installation is complete, the wall may then be painted and wili appear smooth and free of defects.
Certain conditions which alter the surface of the cement occur after the use of conventional taping methods. These result primarily from shrinkage and warpage and are outside the control of the Worker at the time of the installation. In a matter of weeks after the job is iinished, certain defects appear which results in bad appearance and dissatisfaction.
Accordingly, the most important object of this invention is to provide a taping material that may be applied to a joint which will maintain the finish, although shrinkage and warpage of the materials ordinarily used may occur.
Another object of this invention is to provide a finishing process for dry wall construction which will eliminate bad effects resulting from changes in the materials used over a period of time.
A still further object of this invention is to provide a taping structure having characteristics simplifying the installation and reducing the skill required in the workman to obtain results of a better quality than those previously obtainable.
Another important object of the invention is to provide a taping material which controls the warpage and beading of the plasterboard after the installation is completed in such a manner that defects do not later appear and damage the appearance of the wall or ceiling.
Other objects and advantages more or less ancillary to the foregoing, and the manner in which all the various objects are realized, will appear in the following description, which considered in connection with the accomi 2 panying'drawings sets forth the preferred embodiment of the invention'.
In the drawings: Y w
Fig. l isa sectional` view of a finishedl dry wall joint utilizingthe preferredl embodiment of our invention.
.EitgrZf isa' perspective view of the tape;
Fig. Sji's anlen'dlvie'w of the'tape, and y j n Figs 4V is a structural view of a` finished dry wallboard aftert` eshrinkagejand beading has' taken place."
Referring rstf` tohFig.` 1, a typical dry wall `joint is shown therein, wherein; a wallboard 10` and :awallboard 12 are mounted in Ja'lnuttifngY relationship onl the franjej 14. wallboards 10' and 12I areiaiixed to the frame 1'4 by the use'ofnailsv 16'.y j p h The wallboards 10 and 12 are redu'cedi inthickness along the margins thereof which provides a sloping 'snrface 18 recessed from the level of the general wall sur- 4face for receiving the nails 16 in order that theheads of the nails 16 may' be below the surface of the finished wall and completely covered'.
Tofh'id'e the joint and to make a smooth wall surface, aA treatment is applied to the joint area which hides the joint and" forms :a continuation of the smooth surface of the wallboards 10 and 12. Cement is iirst applied to the surface 18 and introduced into the crevice, if any, between the confronting ends of the wallboards 10 and 12. Ai tapeA 20'as' shown in Figs. 2 and 3 is then coated with cementwand placed' over the joint area. The tape 26 is inthe Vform of a strip of paper scarfed at the longitudinal edgesltoobtain a thin orfeathered edge. The tape 20 alsoh'as; ajmetal` tape 22 fixed to the center of the paper tape 20 byfgluing'jtlie metal tape 22 being approximately 5% ofzair inc h" wide' and having a thickness ofV approxirnatelyOZOiof an inch. `The function of the metal tap: 2'2"'isto'provide'a'centralV rigid portion which will rlesi'st bending in a transverse direction and be suicientl'y lli-:xiible in a longitudinal direction to accommodate for unevenness in the wallboard installation. After the tape 2t) is in position, further coats of cement are applied thereover as required to form a level and smooth surface over the joint.
When the tape 20 is in position as shown in Fig. l and the cement shrinks at the seam area, the tape 22 has sufficient lateral strength to support the surface cement while allowing the cement beneath the tape to break away, thus maintaining the surface of the wall in unaltered condition and unaffected by shrinkage which results from ultimate drying of the cement, for weeks, after the job is completed.
The metal strip 22 tends to support the paper strip 20 in such a manner that the pressure of the broad knife used to apply and smooth the cement is not critical. Without the metal strip 22, it is possible to press too hard, therefore, forcing out the cement from beneath the tape 20 with the result that due to unevenness in the plasterboard 10 and 12, dry spots will occur where there is insuilicient cement to form a bond and the tape being unbonded, tends to blister or raise from the wallboard. The metal tape therefor, operates as a gauge and reduces the skill requirement for the Workman to do an adequate job in installing the tape by distributing an optimum quantity of cement in the tape area.
The wallboards 10 and 12 are formed from gypsum, having a paper cover which extends around the abutting ends of the board. When the wallboard is taped, moisture from the cement enters the board and softens the paper. After the cement dries, which may take weeks, depending upon the humidity and location of the wall, the extreme edges of the wallboard tend to raise, which, without the use of this invention would produce an objectionable line across the finished surface of the wall.
The effects of the drying and aging of the finished joint s best illustrated n Fig. 4 which shows the upturned beading 24 at the edges of the boards 10 and 12 and also the shrinkage of the cement 18 in the joint area. It is noted that the surface of the joint is unaffected by any changes which take place immediately below thestrip 2-2 since the joint treatment is supported inthe previously finished condition. Without such a strip, the outer surface of the joint would follow the contours of the shrunken material and the beaded ends with the result that an irregularity would appear on the surface which would be readily noticeable under normal lighting conditions especially when found in the ceiling construction. Also with the metal strip 22 in place, a few thousandths of an inch spacing results which will accommodate the twisting action of the wallboard if it ,takesy place beneath the center tape. The smooth, uniform surface established by working the cement in the ordinary installation is not affected therefore, and the unsightly lines which would otherwise appear due to the twisting of the wallboard are eliminated, It is possible, therefore, to produce a permanent iine nish and eliminate ditlicult and expensive reworking of the joints some time after the walls have been tinished and decorated.
It is to be understood that the specific nature of the present disclosure is not intended to be restrictive or coniining and that various rearrangements of parts and modiications of design may be resorted to without departing from the scope or spirit of the invention as herein claimed.
Having thus described my invention, what We claim and desire to be secured by Letters Patent is:
1. In dry wall construction a pair of panels attached to a supporting member in abutting relation to form a joint, a strip of thin metal over said joint secured by cement, a web of thin pape-like material covering said strip and being cemented to said panels at each side of said strip, and a coating of cement applied over said Web to form a smooth continuation of the surface of said panels.
2. In dry wall construction a pair of panels attached to a supporting member in abutting relation to form a joint, a strip of thin metal over said joint secured by cement, a web of thin pape-like material covering said strip and being cemented to said panels at each side of said strip, and a coating of cement applied over said web to form a smooth continuation of the surface of said panels, said strip being atiixed to said web along the center line thereof.
3. In dry wall construction a pair of panels attached to a supporting member in abutting relation to form a joint, cement on said panels adjacent said joint, a strip of thin metal over said joint, a web of thin paper-like material covering said strip and having a portion at each side of. said strip respectively, a coating of cement applied over said web to form a smooth continuation of the surface of said panels.
4. In dry wall construction a pair of panels attached to a supporting member in abutting relation to form a joint, cement on said panels adjacent said joint, a strip of thin metal over said joint, a web of thin paper-like material covering said strip and having a portion at each side of said strip respectively, a coating of cement applied over said web to form a smooth continuation of the surface of said panels, said strip being affixed to said web along the center line thereof.
References Cited in the file of this patent UNITED STATES PATENTS 1,703,667 Green Feb. 26, 1929 1,970,989 Walker Aug. 2l, 1934 1,999,741 Schultz Apr. 30, 1935 2,181,530 Davenport Nov. 28, 1939 2,231,529 Dey Feb. 11, 1941 V2,314,523 Speer Mar. 23, 1943 FOREIGN PATENTS 580,999 Great Britain Sept. 26, 1946