[4] Drilling, Bolting and Learning

This story is part of a series on route development. Click this tag to see all

I was excited, it was my first time… hauling a dense and heavy pack containing a 36V hammer drill, two charge packs and hunks of metal. My first day out bolting was not quite a success but at least I accomplished bringing the heaviest pack yet up the loose dusty hill to the cliff. Luckily, I learned the hard way so you don’t have to.

How to Fail at Bolting

I jugged the line and hauled up my bag of equipment. I spent about 15-20 minutes trying to find the right place for anchors that would serve the lines below with minimal rope drag. My options were either to place more anchors with no rope drag or place a single, more versatile anchor. I ended going with the single, thinking that if the area gets more traffic I can add more anchors. 

I got setup, a little trouble getting the long drill bit to seat straight into the drill without wobble. As every other time I do work on the upper tier, I was on my static line in rappel mode with a third hand. Meaning I was alone and hands free into my mega webbing anchor.

A Test in Patience

I started drilling on ‘high torque’ mode because I figured drilling rock I want all the torque I can get. Half an hour later, I had drilled half an inch. I switch it to ‘high speed’ mode and started making at least twice the progress. However, I saw the heat scaring rising up the drill bit. I thought the only kind of rock that should take this long was Quartzite (Metamorphic Granite) which is super hard and can take down a drill bit in 1-3 holes. My volcanic rock was so less dense than Granite I thought it would be less than half hour a hole. However, after 1.5 hrs I had drilled 3” and still had a half inch before I could hammer in my first expansion bolt.

I looked at my drill bit and it almost looked like the carbide coating had worn off. So I called it day after it was unclear if I was really making progress and contacted Fixe to see if they could offer some advice. The owner in the installation videos always says to call if you have a question. 

I was sore from putting all of my weight into the drill for hours while trying to maintain awkward positions. You ideally want to be a statue, but it is hard to keep such a position for a couple minutes without concerted effort. Any little shift of weight, esp. in the beginning, can change the orientation of the drill.

My hands were vibrating for the next 24 hrs. Which is important because there is vibrational disorder from using hand tools which can get quite bad. While they say ‘let the tool do the work’ the tool wasn’t really doing the work so I had really pushed into it with harder grips then might be advised. My two solutions were to get anti-vibration gloves and reach out to Fixe to see if I can figure out what went wrong with my technique. 

How to Go About Bolting

A solid anchor on a route I’m developing with each fixed piece made of Stainless Steel.

After speaking with a few people who have bolted for a couple decades, I realized I probably needed a stronger, more powerful drill. I purchased a Bosch RH328VC-36K-RT 36V Cordless Lithium-Ion 1-1/8 in. SDS-Plus Rotary Hammer and my 1.5 hour disaster was replaced by 1-5min drilled holes.

I also updated my drill bits to get some of the most hearty SDS Bulldog Xtreme Rotary Hammer Bits in 3/8″ and 1/2″ so I could drill both bolt sizes.

Where to place a bolt

The things to pay attention when drilling a bolt are:

  • Lay out the hanger so you can see if it will be flush against the rock
  • Ensure minimum spacing between bolts (typically 4-6″, mentioned in the bolt technical specs)
  • Choose solid rock quality and go to glue-ins if there is concern around strength
  • Ensure you drill deep enough, you don’t want to have to pull a bolt out (if even possible)

Choosing the Bolts

After the excitement of buying a drill, the next equipment consideration is what kind of bolt/hanger/anchor to use. While the speaker can get side-tracked a bit in the videos… I watched Fixe’s installation videos to help understand how to select the equipment and install it. I landed on getting a couple glue-ins and several 5-piece bolts. Rock quality would dictate which one I would use. Onsite, I felt the rock was hard enough for a 5-piece and didn’t need a glue-in.

Options with bolts are type (glue in, 5-piece, etc.), material (plated steel, stainless, titanium), diameter (3/8” or 1/2”) and length (2-4”).  For this rock it seemed hard but had cruft so I chose:

  • 5-piece expansion bolts with a couple glue-ins in case there was a weak area
  • Stainless steel, even though plated steel is probably fine in the Eastern Sierra High Desert… I didn’t want anyone to have to replace an anchor because of rust or damage when I could have just paid for stainless steel
  • 3/8” Diameter – smaller holes drill faster and seemed good enough for the rock
  • Smaller lengths – the longer lengths might be for much less quality rock like sandstone.

WARNING: DO NOT MIX METALS. Plated Steel (PS), Stainless Steel (SS/PDX) and Aluminum used together will cause one of these metals to wear and weaken due to Galvanic Corrosion at their contact points.

Brice’s Quick Equipment Checklist/Reference

A good haul of new climbing equipment!

We already discussed the basic drilling equipment choices above:

  • Drill and SDS drill bit
  • Blow tube (for clearing dust) and wire brush (for cleaning dust)

Whenever we buy equipment that is not UIAA rated for climbing, we need to be very careful. Things like chain can be one example. I developed the following guidance for chain:

  • 8000+ lbs (35 kN) breaking limit and 2800-4000 lbs (12-18 kN) working limit.
  • Stainless Steel is going to have a higher weight vs. plated for the same strength
  • Inside diameter needs to be > 0.5″ to allow all ropes to pull through

This may be overly built out, but without a UIAA rating under climbing conditions this was what I was comfortable with. I also realized that I could go down significantly to just body weight for rappelling with the chain, but I was concerned someone might use the chain instead of bolts as the anchor. I’d hate for my equipment to cause anyone injury due a misunderstanding.

My Go-To Equipment

Additional Needed Equipment

  • Torque Wrench needed for hour bolt’s technical specs. and a 1/2′ socket for the 3/8″ bolt
  • Chain cutter large enough to handle our heavy chain
  • Aid Hammer to tap the bolt into its new hole.
Big chain needs a big cutter… and actually two cuts because I couldn’t bend the chain.

Special Needs for Glue-ins

  • Adhesive: Powers 286ml Acrylic Glue Cartridge
  • Duct tape to tape in the bolt / glue, esp. when overhung
  • Rag to mop up any spilling over glue

Want to see some bad drilling in action? Watch me spend far too much time trying to drill a hole with the wrong drill in this short documentary on the development of Storybook Cliff.