REMOVING RESIDENTIAL WINDOW SECURITY GATES, “QUICK AND DIRTY”

REMOVING RESIDENTIAL WINDOW SECURITY GATES, “QUICK AND DIRTY”

PART 2: AN ENGINEERED SOLUTION

BY MARTY VITALE

After discussing the window gate problem and the tool ideas with my brother Vic in June 1995, I contacted some of the firefighters we routinely use as consultants on firefighting problems and tools in various areas and our engineering staff.

The information we gathered showed that there is no “standard” window gate installation, but a variety of gates and anchoring methods are used. The first thing that became evident was that the term “gate” is incorrect when describing the majority of these window coverings. A gate by definition is a doorway, an opening, an entrance, a portal, or a passage. Very few of the typical window gate installations are hinged or capable of being opened in the conventional sense.

The window coverings could be an ornamental wrought iron grillwork or a framework of angle iron filled with a heavy welded wire mesh screening or simply a series of iron bars welded in a frame to similar bars running the opposite direction that serve as anchor points for the assembly. Any of these assemblies could be anchored in a masonry building by drilling holes in the bricks and inserting iron rods to which the grille assembly is welded, if the assembly is set into the window opening. Or they could be part of an installation in which the gates sit away from the wall; the anchor points are often “L”-shaped and set into holes drilled in the brick work. In both these installations, the anchor holes often are filled with molten lead that was tamped down to make a strong anchor. The gates could also be bolted in place with lag bolts if the building is of frame construction and with any number of different style masonry anchor assemblies set into drilled holes if the building is brick. There is no rhyme or reason to the number of anchor points used, but the minimum usually is four, two on each side of the grille. Most installations use many more anchor points.

Some installations using angle iron as the perimeter of the “gate” may be anchored using the latest pop rivet-style anchor. A small-diameter hole is drilled into the building; a special nail and sleeve, about the same size as the hole, are placed in the hole; and the nail is driven in the installation. In most of these installations, multiple rivets are used; and the “gate” has many anchor points.

We also found that it probably takes less than 1,000 pounds of force to pull the “typical” anchors from an unreinforced masonry (ordinary constructed) building if the bricks have been cracked by striking them with a tool at the anchor point.

THE HALLIGAN FORK GATE PULLER

The Halligan Fork Gate Puller–so named because the cable locks into the root of the fork of the halligan–was the original prototype tool developed with these parameters in mind. It is constructed of aircraft-quality stainless-steel wire rope cable. It has a grab hook with a one-inch capacity on one end, which has been swaged to the cable for a smooth union. We built the stops for adjusting the tool`s length by swaging four one-inch-long stainless-steel stops on the other end of the cable 212 inches apart. This allows the length of the cable to be changed in 212-inch increments to a total adjustment of 10 inches.

The cable has a rated working strength of 6,600 pounds and a safety factor of four. We felt that covering the cable was right for this tool. The cable is smooth enough. As an additional safety factor, we ruled out a coated cable. If the working limit is exceeded or the cable is severely strained, it would tend to show it by becoming rough or appearing to be a loose weave at the strain point. If the cable was covered, it might be difficult to see this damage to the cable. The complete tool is very light, weighing about 2.5 pounds. Since the cable is very flexible, the tool can be rolled up and carried in a pocket.

In test and evaluation, the average firefighter could pull the gates off the building using this tool on a 30-inch halligan tool, generally in a shorter time than with most power tools. We used the 30-inch for tests because it is the standard size halligan of FDNY and if the 30-inch length was ample, then the longer 36- and 42-inch models would also work as the leverage bar for the tool by increasing the cable`s length.

I sent the prototype tool to my brother in July. He showed it to the group that played with the idea and then gave it to Buckheit for evaluation.

EVALUATION RESULTS

Buckheit`s evaluation showed the tool worked but needed some fine tuning. When it was built, it was felt the adz would be the fulcrum point and the cable would run over the striking surface for the adz. In practice, it was found that if the point of the adz blade and the horn of the halligan were used as dual fulcrum points, the halligan tool was very steady and resisted any rocking motion. This position caused the cable to slip off the adz striking surface. Buckheit solved this problem by filing a small notch into the corner where the striking surfaces for the adz and the horn meet to act as a cable guide. He used a file made to sharpen a chain saw, which, unlike a rat-tailed file, is a constant diameter. This works out very well; the cable remains in this notch. He also added a clip on the cable, similar to that used to hold the brake cables to a bicycle frame, allowing the cable to be clipped to the shaft of the halligan to keep it in alignment.

Buckheit also wanted greater adjusting ability for length and suggested putting two additional stop positions in between the existing ones. He wanted these additional stops to be free on the cable so that one or both could be positioned to ride inside the fork for almost infinite length adjustment. The other change he wanted was to shorten the hook swaging area by three-quarters of an inch if possible so the hook would not ride on the halligan when the cable is in the shortest stop. He did not want to increase the length of the cable between the first stop and the hook, although it would have the hook clear the halligan and make the tool longer. He felt that in some operations, the shortest cable position was just right; but the hook interfered by riding on the halligan. He wanted the hook`s length shortened.

After working with this tool, Buckheit also had some ideas for other versions that were shorter and used the other working parts of the halligan tool to anchor the cable.

In the original idea, the blade of the adz would serve as the starting point for the fulcrum, and the tool would rotate and pull the striking surface for the adz away from the wall. His new idea was to use a much shorter cable and anchor it in a notch or slot that would be placed in the adz blade. This cable would be similar in design to the one we made up and would include the sliding stops he wanted for the existing tool. In this configuration, the fulcrum would be the driv-ing surface for the fork; and with the cable locked up about six inches above the fork, a greater leverage force could be achieved. This tool would require modifying the adz to create the locking slot for the cable stops.

He also thought the horn of the halligan could be used as the anchor point if a chain with a link large enough to drop over the horn were used. The problem with a typical oval chain link is that it must be very large to be able to drop over the horn`s diameter–making it heavy and difficult to store in a pocket. On the plus side, the halligan would require no modifications to use the tool. If the chain could be used on the horn of the halligan, thousands of halligans already in use could be used with the tool without having to make any modifications.

THE HALLIGAN ADZ GATE PULLER

While we worked on the second generation of the Halligan Fork Gate Puller, we started on the tool we call the Halligan Adz Gate Puller. Since we manufacture halligans that have an optional “A” lock puller machined into the adz, we had the means to lock the cable into this slot with only some minor machining changes. These changes do not affect the ability of the “A” lock puller to pull a lock cylinder, nor does the “A” lock puller affect the forcible entry capability of the halligan adz. This tool is constructed of the same cable-and-hook assembly and has the same swaged stop design and sliding stops for greater adjustment capability as the second-generation of the Halligan Fork Gate Puller. For us, this project was relatively easy; most of the groundwork was done with the first tool, and we already had halligans with the “A” lock puller that serves as the cable-locking slot.

THE HALLIGAN HORN GATE PULLER

The other concept, using the horn to anchor a chain, was more difficult to develop. As Buckheit had stated, a standard chain would be too big and heavy. After much research, we came up with a round link chain that will fit over the horn of a halligan without being big and heavy. The Halligan Horn Gate Puller is a short length of special round link chain with a one-inch grab hook on one end. The overall length of this tool is approximately 10 inches, and it folds up into a compact package that can be carried in a turnout coat pocket. These round links slip over the halligan horn and drop down to the bottom of the horn where the link joins the tool`s shaft, the strongest part of the tool`s horn. The special round link design makes it possible for any link to slip over the horn. Links not in use can be moved out of the way, so the horn will pull only on the link in use. This provides a greater range of adjustment for the halligan to achieve the best pulling angle for the operation and also provides a very stable pull. Because the extra links not in use can be moved out of the way, there is no extra link behind the horn on which the horn can ride, eliminating the chance that the horn will slip when pressure is applied. The striking surface for the fork, on the adz of the halligan, provides the fulcrum point for the halligan horn gate puller.

Prototypes of these three halligan tool-based gate-pulling tools have been built and are being field tested by firefighters in various locations. Initial response has been good; the tools are easy to carry and use and are effective for removing typical residential window gates in situations where the firefighters have a platform from which to work. Where a ladder is required to gain access to the window, it will take longer to pull the gate from its anchor points because the ladder will have to be repositioned.





You must first strike the bricks at the anchor points to crack them with the back of an axe or the adz of the halligan. Then the Halligan Fork End Gate puller is used by placing the adz and horn ends against the building wall, hooking the cable hook to the gate near the anchor point, and running the cable to the fork end. Position the halligan for the best pulling angle, and use the stop position in the fork that will achieve this angle. Levering the halligan fork end will pull the gate free. If you are using the halligan adz gate puller, the striking surface for driving the fork is placed against the wall, the hook is placed on the gate, the halligan is angled for the best pull, and the cable stop that achieves this angle is dropped in the slot behind the adz. Levering the fork end removes the gate. The halligan horn gate puller is used in similar fashion, dropping the chain line that best achieves the best pulling angle over the tool`s horn.



The halligan horn gate puller will work with any standard halligan tool–no modifications to the tool are required.


The halligan adz gate puller can be used with a halligan after grinding a notch into the blade for the cable to pass through so the stops on the cable ride on the underside of the adz blade.

MARTY VITALE is an engineer with Iowa-American Firefighting Equipment Co., Inc., in Osceola, Iowa, manufacturer of specialized firefighting tools and equipment. He has a degree in metallurgical engineering from Lehigh University.

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