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Five-piece Bolts   

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The five-piece, such as the Power-bolt (also known as the rawl bolt) and the Hilti HSL, is easy to spot on the rock by its flat hex-head with no visible threads. Originally developed as a construction bolt, they are available in many different sizes and materials. Powers and Hilti have done extensive research on their strength in various concrete mediums, providing more specifications than many of the climbing-specific manufacturers.

Five-piece bolts with 3/8” and ½” diameters are strong and well suited for climbing. In many cases they can be removed from their hole, inspected and replaced if needed. Because the sleeve runs roughly the length of the bolt, their longitudinal holding power is stronger than a comparable wedge bolt in any given rock type. In the 1/2” diameter, five-piece bolts are also well suited for soft or inconsistent rock (if the appropriate length). With so many variations, care should be taken when selecting a sleeve bolt. Stainless and plated steel versions are both available and should be paired with a like metal hanger in order to avoid accelerated galvanic corrosion.

Stainless ½” five-piece Power-bolts have a plated steel cone. The engineers at Powers apparently found that plated steel is better suited for the pressure exerted on the cone in the larger sizes, and that this added strength outweighs the risk of galvanic corrosion. However, this configuration may shorten the life of the bolt relative to units that do not mix alloys. Today, stainless ½” five-piece bolts are becoming more popular, as they are very strong and their size makes them easier to work with.

The sleeve of the five-piece bolt can become lodged inside the hole, either resulting in a botched placement or a hole that cannot be reused. This issue is of greater concern with the smaller 3/8” diameter bolts, when placing the bolts on lead, or when using long versions that have a separate extension sleeve. Additionally, two hands are usually necessary when placing sleeve bolts, which can be an issue if bolting on lead.

A lot of conflicting information has circulated concerning the proper hanger size and the use of the washer on five-piece bolts. While a 10mm hanger will fit between the sleeve and the head, Kevin Daniels, owner of Fixe USA, strongly recommends that all ½” power bolts be paired with a 12mm hanger to be placed over the sleeve. He also strongly recommends that they be used with the washers, which are placed between the hanger and the bolt head.
Placement: Five-piece bolts are placed much like any other mechanical bolt. It is important to thoroughly clean the hole in the rock before the bolt is placed. Rock dust can easily cause the sleeve to bind inside the hole or cause problems getting the bolt to engage. Use a hole brush and air to clean the hole before installing the bolt.

Rock Climbing Photo: Rawl five piece bolt

Rawl five piece bolt
Removal: Five-piece bolts are generally removable. The bolt is loosened and tapped with a hammer to free the cone from the sleeve. At this point, the bolt may just slide out. However, if the sleeve is at all stuck or bound against the inside of the hole, the process is a bit more involved.

To remove five-piece bolts that have a stuck sleeve, first completely unscrew the bolt and remove it from the hole. Now use a tool to grab the sleeve and pull it out. Longer versions may require pulling the sleeve extender before the sleeve itself can be pulled from the hole. This can get tricky due to the small diameter of the hole (especially with 3/8” bolts). One method involves the modification of a 7/64” t-handle hex wrench. Basically, the end of the wrench is bent at a 90° angle, within either 3/8” or ½” of the end depending on the bolt diameter. Heating the wrench with a torch may be necessary in order to get a clean bend. Use a grinder to shorten the end if the tool will not fit in the sleeve. You will finish with a t-handle hook that can be inserted and hooked onto the stuck sleeve. Power-bolt sleeves have a triangular hole on the side that will accommodate the hook. The cone will be the only remaining thing in the hole. Fish it out with a tool or screw the bolt back into the cone until it can be pulled out.

Rusted or off-center sleeves may not pull easily with the hook method described above. Leave the sleeve in and patch the hole or attempt to extract the sleeve using an appropriately sized tap fashioned into an extraction tool. There are many ways to approach this technique, most of which will require some fabrication of a self-tapping extraction tool. At the most basic level, a tap is screwed into the sleeve until it has sufficient grip on the inside of the sleeve. Using leverage or funking, pull the tap out with the attached sleeve. Be sure to free the cone from the sleeve first via a hammer blow to the partially removed bolt. Otherwise, these efforts will prove futile.

ClimbTech is currently in the development phase for a sleeve extractor adapter for use with a rotary drill. Using a method similar to the self-tapping technique described above, the drill turns a threaded rod which forces the sleeve from the back of the hole. This tool will hopefully prove much faster and more reliable than other methods currently in use and will make sleeve removal a possibility for those not inclined to invent their own methods.

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