• Can Sleeping on Your Rope Cause Damage?
  • Will Dog Urine Harm My Rope?
  • What's the Point of Spotting Highball Boulder Problems?
  • Closet Car: Is it Safe to Store Climbing Gear in Your Vehicle?
  • Do Twists in a Figure-8 Knot Reduce Its Safety?
  • Can a Belay Device Jam Open?
  • Marking the Middle of a Rope
  • Fitting Rock Shoes to Problematic Feet
  • Defining the Cheater Stick and Stick Clip
  • When Your Partner Steals Your Gear...
  • Can You Climb on a Wet Rope?
  • Can You Decrease Fall Factor?
  • Should You Be Allowed to Practice Lead Falls in the Gym?
  • Rope Certifications: Twins, Doubles, or Both?
  • Are Cam Placements Compromised in Wet Rock?
  • What's the Correct Way to Girth Hitch to Your Harness?
  • Choosing Ice Screw Length
  • The Holding Power of Nuts
  • Should You Clip the Belay As Your First Lead Pro?
  • Should I Worry About Spinning Bolt Hangers?
  • Belay-Loop Myth
  • Rock Cleaning Made Easy
  • More, on the EDK
  • Why Not Clip Directly to Cam-Stem Loops?
  • Can You Recommend A Self-Release Knot?
  • What's The Protocol For Naming a Route After Yourself?
  • Is Dropped Gear Still Safe?
  • Can Ropes and Slings Be Contaminated By Essential Oils?
  • Is It Okay to Wear Socks with Rock Climbing Shoes?
  • How Should You Test Gear Placements?
  • Can You Use Adhesive Tape on Ropes, Cords, Webbing?
  • A Better EDK?
  • What's the Difference Between a Double and a Single Rope?
  • Does It Count As a Free Ascent If You Grab the Anchor?
  • Can You Use Cams As Passive Pro?
  • I Found a Rope - Is it Safe to Use?
  • Am I Using a Daisy Chain Wrong?
  • Should I Buy a Plastic or Foam Helmet?
  • Why Doesn't Anyone Climb in Knickers Anymore?
  • Is Weight or Range More Important in Cams?
  • The Mysterious Phenomenon of Rope Shrinkage
  • Worst-Case Scenario - A Factor 2 Fall
  • The Trouble With Glue-In Bolts
  • The Nuts and Bolts of Nuts and Bolts
  • Why Are Climbing Shoes So Expensive?
  • Flaws in the Yosemite Decimal System
  • How Durable is Trad Gear?
  • Using Super Glue on Your Fingers
  • The Worst Gear Ever Invented
  • Rap Ring Strength
  • Spinners and Losers
  • Why Do People Use Oval Biners?
  • Is it Ethical to Clean a New Route?
  • Aid Climbing = Moped Riding
  • Cam Care and Maintenance Guide
  • Will Sweat Harm My Harness?
  • Should You Use Rope or Webbing to Connect to an Anchor?
  • Choosing Between C4s and Friends
  • Can You Lead On a Static Rope?
  • Can I Use Climbing Bolts For Anchors in a Gym?
  • Are My Modified Crampons Safe?
  • Are Falls Held or Breaking Strength More Important In a Rope?
  • Does Poop Harm a Climbing Rope?
  • Are Homemade Draws Reliable?
  • Shopping for Economy Carabiners
  • When You Fly, Can You Carry On Climbing Gear?
  • Can I Trust Fixed Draws?
  • Which Helmet WIll Fit My Big Head?
  • Are Adjustable Leg Loops Useful?
  • Should I clip Ice Screws with Screamers?
  • How do I Make a Bomber Anchor?
  • Can I Modify my Crampon Without Compromising the Integrity?
  • How to Place Ice Tools and Crampons - Will Gadd's Tips
  • How to Place Ice Screws - Will Gadd's Tips
  • Hot Versus Cold Forging
  • Caring For Your Fingertips
  • Are Sewn Slings Stronger Than Knotted Ones?
  • When to Replace Climbing Webbing
  • Using Grip Dip To Color Code Gear
  • The Benefits of Cotton
  • How to Pull a Rappel Rope
  • How to Properly Orient a Carabiner Gate
  • Are My Fuzzy Quickdraws Safe?
  • How to Stretch Climbing Shoes
  • Are 1/2-inch bolts really better than 3/8-inch?
  • Should I Resole My Rock Shoes?
  • How to Hand Drill
  • Lonely Climber Looking for Woman
  • Is My Invented Knot Safe?
  • Difference Between Double and Twin Ropes
  • Dealing With an Argumentative Partner
  • Will Antifreeze Ruin Rope?
  • Why Is a Rack Called a Rack?
  • Rock Shoes For a Big Guy
  • Do They Kill Geese To Get Down?
  • How to Wash a Rope
  • Do Cam Teeth Do Anything?
  • Can I Fix Delaminated Rock Shoes?
  • Can I Mix a Static With a Dynamic Rope for Rappelling?
  • Should You Lower Or Rap Through Anchors?
  • How Should The Middle Man Tie In?
  • How Do I Get a Good Climbing Man?
  • Do Falls Weaken Bolts?
  • Should I Rope Solo?
  • Should I Angle Ice Screws Down?
  • How Should Old Climbers Train?
  • Can I Make a Belay Loop?
  • Reusing Ice Screw Holes
  • Overcoming the Fear of Falling
  • Choosing a Stove Fuel
  • Will My Hiking Boots Work With Crampons?
  • Do Heavy People Shock Load the Rope?
  • Can Offset Cams Subsitute for Regular Cams?
  • Can I Resling My Cams Myself?
  • Are Older Alien Cams Safe?
  • Will sports drinks freeze more slowly than water?
  • The Truth About Climbing Supplements
  • Can I Make My Leashed Tools, Leashless?
  • Rope Stretch Facts
  • How To Cut a Rope Without a Knife
  • Secrets of the Toprope
  • How to Sharpen Crampons
  • Should I Become a Climbing Guide?
  • Preventing Climbing Rope Wear
  • How to Remove an Old Bolt
  • How to Customize Ice Tool Picks
  • Double Rope Facts
  • Do It Yourself Fruit Boots
  • Climbing Rope Sheath Slippage
  • Rockfall Safety
  • Do Screamers Work?
  • Climbing Skin Care
  • Selecting a Gym Rope
  • Quick Links for Climbing
  • Are Russian Cams Good?
  • When To Retire Climbing Gear and Ropes
  • Should I Get a Link Cam?
  • How to Get a Climbing Mate
  • Using Steel Carabiners for Fixed Quickdraws
  • Petzl Tibloc and Climbing Rope Sheath Damage
  • Overcoming Anger
  • Fixing a Spinning Bolt
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    The Trouble With Glue-In Bolts


    Here in New Mexico's volcanic rock we sometimes use glue to keep the rock from crumbling around the bolt. In one instance, glue was used in a vertically placed bolt in basalt to increase the pull-out strength, but this bolt actually pulled out! In other areas I have seen a silicone glue used in the hole to keep water out. Is there a rule for when to put glue in a bolt hole? Should we be specific about the types of glue?

    —Aaron, Santa Fe, NM

    Properly placing glue-ins ranks up there with replacing the brakes on your car—it takes tools and know-how, and it is easy to botch the job.Not to be indelicate, but the situation you detail makes me never want to climb in New Mexico. Glue-in bolts may be the strongest, longest-lasting and most bomber of all bolts, but I’d rather cut myself and free swim off the Great Barrier Reef than clip glue-ins that are someone's science experiment.

    Properly placing glue-ins ranks up there with replacing the brakes on your car—it takes tools and know-how, and it is easy to botch the job.

    For a glue-in to be strong, the glue has to stick to the bolt and to the rock. Getting these bonds isn’t as easy as you might think. Hole cleanliness is paramount. Unlike mechanical bolts, where a quick toot on a piece of aquarium tubing suffices to clear the drill dust from the hole, glue-ins require a hole that is absolutely spotless. Think of your colon prepped for a colonoscopy.

    To ram home how important the cleaning process is, tests conducted by Bolt Products show that a dirty hole can reduce a glue-in’s holding power by 90 percent.

    To answer your question about the glue type, yes, there are specific glues to use with specific bolts. Bolt glues are resins. Some are two parts and you mix them with a special caulking gun. One popular glue is the suppository-like ampule that breaks and mixes in the hole. The manufacturers of this type recommend spinning the bolt in the hole at a minimum of 250 rpms, a task that requires mounting the bolt in the chuck of a power drill and spinning it at full bore. Spinning the bolt mixes the glue with the hardener. Since most bolts won’t fit in a drill (use threaded rod and get a rod-to-SDS chuck adapter from Hilti), climbers simply hand spin these bolts. As you can imagine, it is impossible to hand spin a bolt at 250 rpms—we can bet that 100 percent of bolts placed by hand did not have the glue mixed to specification.

    That these bolts are not failing by the droves is testament to the massive overkill built into them by the construction industry.

    The bolt failure you had in New Mexico could have been caused by a poor glue bond, but probably the glue gummed up the bolt’s workings and it didn’t tighten. Putting any type of glue or caulking in a mechanical bolt (Powers five-piece, for example) hole is for this reason a no-no. Logically, gluing a mechanical bolt would seem to fortify it, but any mechanical bolt fits in the hole so snugly that most of the glue will either get pushed to the back of the hole, or forced out of the hole. There will be little, if any, glue on the bolt shaft or along the length of the hole. If you are going to use glue in soft rock, use actual glue-in bolts, such as 1/2- by 6-inch threaded rod. I’ve placed a bushel-full of this type bolt in rock that was no better than soap and 25 years later they are still in use.

    You probably noticed that silicone caulking—the stuff you said you saw—is not on the list of approved bolt glues. Silicone caulking is sealant, not glue. Getting silicone caulking in the hole will compromise the bolt’s frictional grip and/or jam up its mechanical workings. Don’t use it!

    Silicone caulking (or a rubber washer) might serve to temporarily seal over the hole and bolt, preventing water from getting in, but I think caulking causes more problems than it solves. The caulking hides the bolt, preventing you from visually inspecting it, and the caulking eventually cracks and pulls away from the rock, letting water in and making it harder for the bolt hole to dry.

    Everything I have just noted is only an outline of what it takes to install glue-ins. Before you attempt to place a glue-in, read everything on the website bolt-products.com. This site covers bolting gear, design, glues and glue systems and installation tips in great detail. It also gives results for various tests on glue-ins—the data is often eye-opening. Gear Guy has spoken!


    This article was published in Rock and Ice issue 205 (October 2012).


    GOT A QUESTION? E-mail Gear Guy! rockandicegearguy@gmail.com

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