1. Field of the Invention
This invention relates to a simplified, potential low cost system for drywall tape installation.
Since the tape is fully imbedded after only one operation, there is a reduction in labor to complete the drywall taping procedure.
2. Background Art
The repetitive and laborious process of taping drywall has lead to several systems of taping, each of which have serous undersirable limitations.
Since the advent of drywall technology, the taping of the seams created when sheets of drywall are nailed in place has been a pedestrian exercise in handling the paper tape and adhesive wet mud. The components are currently sold separately and are combined only upon actual application with all prior art.
In the time consuming manual application of the taping materials, the adhesive mud is manually scooped out of a container and applied with a smearing action to drywall seams with a drywall knife. Then dry paper tape is un-rolled and laid upon the adhesive surface and wiped down onto the wet mud. The tape is later top coated with more mud and wiped smooth after each coat to flatten the surface. The materials are allowed to dry between coats.
One layer of mud goes under the tape to achieve adhesion and at least two layers of mud are commonly applied over the tape to "embed" the tape within the mud. The mud is allowed to dry between coats. Mud is applied to the drywall seams and wiped down until the mud appears smooth and the gap between the drywall panels are made flat.
The predominate commercial taping system in use, is the Ames system. The Ames system consist of a series of tools designed to handle both dry, non-adhesive paper tape and wet adhesive mud to make the application procedure faster than manual installation.
The Ames system tape tools consist of; a manual mud pump, a taper tool, roller, finishers and a standard drywall knife. Many of the Ames tools are complex, rather expensive and require extensive training, adjustment and manual dexterity to operate.
In the Ames system the drywall mud is pumped out of a bucket into a cylinder within the Ames taper. The Ames taper tool holds a roll of dry paper tape. When the cylinder is full of mud the taper is held against the seam and the taper head is rolled along the seam. The cylinder is emptied of the mud it holds, as a wheel on the head which contains a pulley, reels up a steel cable attached to a piston within the cylinder. The mud then exits the tool out a hole at the head as dry paper tape is rolled onto the mud as it is ejected upon the wall.
The seam must be "wiped down with a drywall knife to complete the taping operation with the Ames system. The seam then requires a top coat of mud to fully imbed the tape.
With the Ames system full embedding occurs only after three operations; Tape and mud application to the drywall, wiping the tape down and then top coating the seam.
The previously mentioned tools have various limitations and short comings. The Ames system is very expensive as it requires many unique part be machined and the tools maintained in proper adjustment. The taper tool is heavy and hard to use. The Ames taper requires that many precision parts operate in the hostile environment of gritty, adhesive viscous drywall mud. The tool must be cleaned, oiled and adjusted often to not breakdown or become jammed and stop working. Parts wear out and break requiring substantial maintenance and expense. The Ames taper does not apply mud to the top side of the drywall tape.
A more primitive taping tool called the "banjo" utilizes the concept of a reel of dry tape that is threaded though a chamber of wet mud as it exits the tool and the muddy tape is then directly applied to the drywall for manual wipe down. As the banjo concentrates all the mud under the tape, very little mud ends up on the back side of the tape. With a banjo taper another coat of mud must be applied to fully embed the tape.
The banjo is slow and inefficient as the mud may not properly and fully coat the underside of the tape, leaving a dry blister under the tape. The banjo is heavy and awkward to use and requires that the muddy tape be wiped down after it is unrolled upon the drywall seam. The banjo will not readily do inside corners and does not apply mud to both sides of the drywall tape.
It would be desirable to have an effective labor saving system that is inexpensive to manufacture, easy to use and light weight. The system should be able to operate in the hostile environment of the materials and not be adversely affected by the mud drying and or a failure to thoroughly clean the tools after each use.
The system should utilize current materials and procedures common to the drywall taping industry. Use of the tools should be natural and easy to learn. It would be desirable to reduce the occurrence of blisters of air which occasionally occur under the tape. The system should fully embed the drywall tape in the initial application; thus reducing the number of required steps and eliminating some labor.