The patented, Positive Force Gate Closing System (PFGCS) is the creation of locksmith David Mowery. For years customers wanted a closer that would keep pool area gates closed and latched without slamming or having to be replaced after a few years. The problem is most pool gates and fencing is five feet tall or less and standard door closers would be in the way of access or egress as this limited height has no overhead clearance. For most pool gates, the only closing options are coil style springs or spring hinges.
Coil springs and spring hinges are designed to become longer under a load. When coil springs are in the unloaded condition, the coils are normally touching. These springs have two significant problems when it comes to closing a gate. The first problem is how much force is exerted to stretch a spring is about the same amount of force exerted by the spring to retract. The greatest amount of energy is at the maximum point of expansion, not at the end of the retraction, which is where a door requires the greatest force in order to operate the lock mechanism’s latch.
In addition, gate springs and hinge springs are not available with controllable retraction. Roughly put, the bigger the spring, the shorter the expansion and the faster the retraction. The speed and force of retraction are increased or decreased simultaneously, not separately.
Over time and under the influence of stress, springs slowly deform (technical term creep). They permanently begin losing their storable mechanical energy. The loss is at the end of the retraction.
This will result in the gate not have sufficient force to close and latch, leaving an unlatched gate. In today’s world, a non-closing pool gate is a significant liability to a homeowner, private and public facilities and homeowner associations.
To solve the pool area gate problem, David developed a way to incorporate a door closer as the closing mechanism. When properly operating, a door closer does not slam the door shut. Instead, the closing force is adjusted to safely close and latch the door at the prescribed speeds.
For form and function, the Positive Force Gate Closing System is based on an overhead concealed door closer whose arm can travel in both directions. Locksmiths have installed these hydraulic closers for over 40 years.
The concealed overhead closer style was chosen because of its compact size and capability of double acting. Unlike a surface-mount door closer, the concealed closer is designed to operate in both directions for center-hung door applications. Surface mounted door closers are handed, operating in one direction only.
With this capability, the Positive Force Gate Closing System can be installed in left or right hand single acting door applications and also double acting applications. Instead of using hinges to secure the gate to the fence, this system incorporates a bottom center hung pivot to ensure smooth opening and closing operation with minimal force.
The Positive Force Gate Closing System is designed for gates that are no more than four feet wide and weigh less than 200 pounds. The closers are spring and speed adjustable to make certain that the different size and weight gates properly close and latch.
There are three Positive Force Gate Closing System Kits. The kit that will be installed for the purpose of this article is the bolt-on kit designed for square tube gates and fencing. The bolt-on kit contains all of the components necessary to install the unit onto a two-inch square fence post and one-inch square gate channel.
The kit includes the closer with K-arm, closer housing, end cap, center hung bottom pivot assembly, modified K-arm housing and Tek screws. The closer housing is mounted onto the hinge post and the modified K-arm housing is mounted onto the top channel (horizontal) adjacent to the hinge post. Unlike standard door applications, the closer body is mounted with the spindle and the short end of the body over the gate.
Positive Force Gate Closing System also has weld-on kits for round (chain link) and square tube fence/gate applications.
A square tube metal fence has top and bottom channels (horizontals) and pickets (verticals) located to provide a maximum four inches opening. Depending upon the supplier, many of these fences and gates are available as separate components, enabling fence and gate installation without requiring a welder.
For this article, Positive Force Gate Closing System provided two five-foot tall fence sections with an opening for a three-foot wide gate. The fence and gate components were purchased from a big box hardware store. The supplied overhead concealed closer used in this installation is a Calibre CA3311 adjustable spring power ADA model with 105 degree back stop and no hold-open. The closer comes with a five-year limited manufacturer’s warranty.
Installing the bolt-on Positive Force Gate Closing System only requires hand tools. The closer housing, bottom pivot and the arm housing are secured to the fence and gate using supplied Tek screws. The gate to fence positioning is a one inch opening between the hinge side of the gate and the fence post. This is because the pivot requires one inch spacing. As an added benefit, this spacing provides a “no pinch” opening for small children placing their fingers or hands between the gate and the fence post. The latch side gate to fence spacing varies depending upon the latching mechanism. A gravity latch and striker bar mechanism will have a wider opening requirement than a lock or exit device.
The Positive Force Gate Closing System Bolt-on Kit is designed to be installed onto a square tube fence where the upper channel for both the fence and the gate are at the same height.
To install the closing system, slide the closer housing onto the top of the hinge side fence post. The housing rests against the fence top channel. The fence channel side of the housing is shorter and positions the closer at the correct height for the modified K-arm housing. If necessary, cut the fence post until the closer housing seats at the proper height.
Slide the modified K-arm housing onto the top of the gate’s hinge edge. Slide the pivot assembly onto the bottom of the gate’s hinge edge. Measure the gate’s length from the bottom of the pivot to the top of the housing. Add 1/8” to this measurement. This provides the spacing between the closer housing and the K-arm housing.
Once the closer housing is in position, measure this distance from the bottom of the closer housing to locate the pivot. Install the bottom pivot using the supplied Tek screws. Make certain the pivot is level.
Slide the gate onto the bottom pivot. Determine the distance between the top of the K-arm housing and the bottom of the closer housing. The gap should be 1/16” to 3/16”. This is sufficient clearance for the gate swing and leaves enough spindle in order to attach the arm.
Install the closer housing onto the fence post and the modified K-arm housing and pivot onto the gate using the supplied Tek screws.
Slide the closer into the housing and secure by installing the housing cap and the mounting screws.
Slide the end load K-arm into the housing with the flat side up. Secure the arm at the center of housing using the two top mount screws. The arm will be adjusted once the gate has been installed. The top screw closest to the hinge side should be tightened. This is because once the gate is mounted onto the fence post, this screw is no longer accessible.
Slide the gate onto the bottom pivot. Position the gate in the opening with the closer spindle sliding into the opening in the K-arm. Swing the gate approximately ninety degrees and install the arm block and secure using the two hex head mounting screws. Operate the gate several times.
Note: The gate should be plumb and have a one inch opening to the fence post.
The K-arm is secured within the gate housing by four screws. The screws are installed and adjusted from the exterior of the housing. The two side screws adjust the lateral positioning of the arm in order to have the gate stop at the desired location. Once lateral adjustment is complete, the two top screws are tightened to secure the arm in place.
To adjust the K-arm, loosen the three screws. The side screws must be loosened before making adjustments. Adjust the two K-arm side screws in the direction of the closer swing to center the gate. If the gate is single acting (a stop mounted to the fence post), the arm can be over adjusted laterally to enable a gate mounted lock or gravity latch to close and latch. This way less closing force will be required.
The Calibre adjustable tension overhead concealed closer has three adjustments: spring power, closing and latching. Spring power is adjusted using a 3/16” hex wrench. A straight slot screwdriver is used to adjust closing and latching speeds. There are two access holes in the closer housing for making adjustments. The closer is factory set for the 8-1/2 pound ADA requirement.
The Positive Force Gate Closing System is designed for swimming pool and pedestrian gates that are single or double acting, up to four feet wide and 200 pounds. The bolt-on kit is compatible with any type of mechanical or electromechanical locking hardware. The metal components can be painted to match existing fence color.
For more information, contact Positive Force Gate Closing System, telephone 714-994-0276 Web Site: www.pfgcs.com.