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Glue in Bolts Vs. Expansion Anchors in limestone


Original Post
Jimmy Yammine · · Ehden, LB · Joined Apr 2015 · Points: 359

I am currently developing a crag and am using expansion bolts.

My question to this enlightened community is why glue-ins are seen in a more favourable light?

More importantly, does this difference, which I'm assuming is its attachment to the rock around the bolt, warrant the mess of glue-ins.

P.S this has to do with limestone bolting in the mountains. NO humidity, SS bolts and cool temps.

Kristoffer · · North Bend, Wa · Joined Feb 2006 · Points: 51

I would think it all boils down to the quality of limestone you are dealing with and how dimensionally correct of a hole you are able to drill within that rock.  I have placed glue-ins (Chem-Stud), wedge bolts and Cobra SuperSleeves, the latter ended up being *my* preferred bolt for the limestone we were climbing.     

Taylor Spiegelberg · · Lander & Sheridan, WY · Joined May 2012 · Points: 1,466

I decided to start using glue in's in limestone for several reasons:

1. Lots of it is soft. Ours has about a 1" crust that's bullet hard, then a soft (in comparison), spongey core. Expansion bolts like powerbolts and wedge bolts can't grab in that spongey rock. A glue in creates an insanely strong bond with the rock, eliminating that problem.

2. Glue in's are more sustainable in the long run. We will have to replace fewer bolts in the long term as most stainless steel glue in's have estimated life spans of 50-150 years depending on who you talk to.

3. I love the idea of place it and forget it. I didn't like thinking about routes I put up developing spinners with wedges bolts and becoming unsafe. Less anxiety for me!

4. Glue in's look SEXY on the wall! They can be camo'ed up real nice and are great for multi use areas.

5. Stainless steel glue ins are actually a pretty cheap option. Most people seem to be able to get glue in's for anywhere from $5-$8 after glue is factored in! Thats cheaper than a stainless powerbolt/hanger combo.

6. They're not messy once you get good at it. After you dial in how many pumps of glue it takes for it to just squeeze out of the hole, you will cut down on the mess and save glue.

Jim Titt · · Germany · Joined Nov 2009 · Points: 490
Jimmy Yammine wrote:

I am currently developing a crag and am using expansion bolts.

My question to this enlightened community is why glue-ins are seen in a more favourable light?

More importantly, does this difference, which I'm assuming is its attachment to the rock around the bolt, warrant the mess of glue-ins.

P.S this has to do with limestone bolting in the mountains. NO humidity, SS bolts and cool temps.

Freeze/thaw is a big hassle, the German Alpine Association only reckon on 10 years for mechanical bolts in Alpine environments. The second issue, especially in limestones is that the extremely high pressure at the contact point of the expansion cone combined with water in the rock could produce rapid erosion of the rock, there are some theories about regarding this but no real decision on whether this occurs, just we know the things keep coming loose. Glue-ins are generally cheaper and certainly have a lower visual impact. And they are stronger.

Edit.And of course you can rap straight off them if you need to retreat or whatever.

Jake Jones · · Richmond, VA · Joined Jul 2011 · Points: 1,729
Taylor Spiegelberg wrote:

I decided to start using glue in's in limestone for several reasons:

1. Lots of it is soft. Ours has about a 1" crust that's bullet hard, then a soft (in comparison), spongey core. Expansion bolts like powerbolts and wedge bolts can't grab in that spongey rock. A glue in creates an insanely strong bond with the rock, eliminating that problem.

2. Glue in's are more sustainable in the long run. We will have to replace fewer bolts in the long term as most stainless steel glue in's have estimated life spans of 50-150 years depending on who you talk to.

3. I love the idea of place it and forget it. I didn't like thinking about routes I put up developing spinners with wedges bolts and becoming unsafe. Less anxiety for me!

4. Glue in's look SEXY on the wall! They can be camo'ed up real nice and are great for multi use areas.

5. Stainless steel glue ins are actually a pretty cheap option. Most people seem to be able to get glue in's for anywhere from $5-$8 after glue is factored in! Thats cheaper than a stainless powerbolt/hanger combo.

6. They're not messy once you get good at it. After you dial in how many pumps of glue it takes for it to just squeeze out of the hole, you will cut down on the mess and save glue.

7.  A big benefit to glue-ins is that holes from extracted 5 piece bolts can be cleaned and re-used for glue-ins often times.  I know this has no bearing on new development, it's just another plus to glue-ins.

The Morse-Bradys · · Lander, WY · Joined Aug 2012 · Points: 3,493

8 - The in the rock portion is incased in glue lessing the chance of corrosion

9 - Better quickdraw interface no gouging no chance of it getting snagged on a bolt stud

10 - Glue ins needs very little to no maintence never need tightening or resetting to have correct orientation 

Francis Haden · · Unknown Hometown · Joined Dec 2016 · Points: 9

Glue-in fixings have numerous advantages over expansion fixings:

  • Significantly stronger bolts than a comparable depth expansion bolt
  • Cannot be stolen
  • No parts that can rotate loose
  • No karabiner damage
  • Can be abseiled from by directly threading the rope through the eye
  • Typically have greater corrosion resistance - this a general statement however crevice corrosion is less of an issue with a glue-in
  • Single piece unit - dissimilar metal corrosion is not an issue
  • Can improve holding power by installing a longer bolt - off the shelf, longer expansion bolts are not available (unless you contact Jim)
  • Best overall system for long life
  • The only sustainable fixed protection system (titanium resin bolts) for stress corrosion cracking affected regions
  • The only type of fixing suitable for ALL rock types
  • Once cured they form a tough, chemical resistant, stress free fixing making them ideal for ‘close-to-edge’ fixings – a major advantage over traditional expansion bolts
  • Visually less obtrusive as they are a '2D fixing' versus a hanger which makes it easier to be seen from all angles (due to the 'L')
  • Can respond to irregular hole quality - any internal pits are filled with adhesive
  • Generally the cheapest fixing when used in bulk

Perhaps stating the obvious but this type of fixing does requires additional competencies and experience to install glue-ins safely and efficiently. That said, it's like most things in life, source training from an adhesive supplier and combine that with a local area mentour so as to adapt work practices to climbing.

With time, most people can place an adequate number of glue-ins per day so then it really becomes an issue that fixings cannot be immediately loaded (generally as this is adhesive dependent). In the 'big picture' however, I rarely find waiting a day to be an issue considering the end product is a much better user experience and longterm outcome.

Jimmy Yammine · · Ehden, LB · Joined Apr 2015 · Points: 359

I would like to thank you all for the soberest and most to the point thread I've seen on MP.

I like your reasons and will be converting to glue-ins in the future.

Jason Todd · · Cody, WY · Joined Apr 2012 · Points: 1,114

One of the downsides is the practical inability to move your bolt placement, should the clipping stance prove less than ideal.  Carefully sussing out placements prior to putting the drill mitigates this, but mistakes in bolt placements are not uncommon.

michalm · · Boulder, CO · Joined Jun 2014 · Points: 207

Admins, this thread should become a sticky on the advantages of glue-ins over mechanical bolts! 

Josh Janes · · Unknown Hometown · Joined Jun 2001 · Points: 9,015

I see “rapping directly from them by threading the rope through the eye” as a disadvantage.

Any experienced installers have tips for keeping nozzles clog-free when equipping a route where there are unplanned or unavoidable delays between each bolt installation? I realize that doing as much prep work as possible beforehand minimizes this but it isn’t always avoidable. My current method is to squeeze a little more epoxy through the nozzle into my plastic bag holster every few minutes if I encounter delays.

Harumpfster Boondoggle · · Between yesterday and today. · Joined Apr 2018 · Points: 133
Kristoffer wrote:

I would think it all boils down to the quality of limestone you are dealing with and how dimensionally correct of a hole you are able to drill within that rock.  I have placed glue-ins (Chem-Stud), wedge bolts and Cobra SuperSleeves, the latter ended up being *my* preferred bolt for the limestone we were climbing.     

Please be sure to use SS hardware.

In softer stone appropriate size wedge anchors (1/2") and length (4") can be entirely adequate and are reasonable. YMMV depending on your stone (limestone is generally fine).

Glue ins become more and more reasonable when many routes are going up at the same time to take advantage of glue issues. Wedge types more useful for a bolt here, a bolt there, sort of approaches (or hand drilled).

Jim, you got any glue-ins that fit a 3/8" or 10mm hole?
Michael Schneiter · · Glenwood Springs, CO · Joined Apr 2002 · Points: 8,829
Josh Janes wrote: I see “rapping directly from them by threading the rope through the eye” as a disadvantage.

Any experienced installers have tips for keeping nozzles clog-free when equipping a route where there are unplanned or unavoidable delays between each bolt installation? I realize that doing as much prep work as possible beforehand minimizes this but it isn’t always avoidable. My current method is to squeeze a little more epoxy through the nozzle into my plastic bag holster every few minutes if I encounter delays.

+1 for that. I also, in general, try to keep the glue as cool as possible by placing bolts while in the shade, at cooler times of the year and/or by keeping it in a soft-sided cooler, sometimes on route. As I'm sure you know, some glues cure faster than others. I know people who stay away from certain glues due to their respective cure times.

Bobby Hutton · · Gold Country CA · Joined Aug 2013 · Points: 824
Harumpfster Boondoggle wrote:




Jim, you got any glue-ins that fit a 3/8" or 10mm hole?

I believe Jim offers solid leg bolts that fit a 10 mm hole. Scroll down to the 8mm Rod Solid Leg Bolt.

Harumpfster Boondoggle · · Between yesterday and today. · Joined Apr 2018 · Points: 133

Gotcha, thx Bobby.

GA Friday?

Francis Haden · · Unknown Hometown · Joined Dec 2016 · Points: 9
Josh Janes wrote: I see “rapping directly from them by threading the rope through the eye” as a disadvantage.

Any experienced installers have tips for keeping nozzles clog-free when equipping a route where there are unplanned or unavoidable delays between each bolt installation? I realize that doing as much prep work as possible beforehand minimizes this but it isn’t always avoidable. My current method is to squeeze a little more epoxy through the nozzle into my plastic bag holster every few minutes if I encounter delays.

Why is that a disadvantage? It's one reason (amongst others) why Jim developed a round bar hanger for mechanical expansion anchors when there is a need to retreat from a high point on a route. Glue-ins do not present an issue in this regard.

The alternative is manky crap left behind on a hanger when people bail e.g.manky quick links that corrode shut and require a cordless angle grinder to remove.

For lower offs or abseil stations then obviously replaceable wear components should be fitted.
eli poss · · Durango, Co · Joined May 2014 · Points: 523
Francis Haden wrote:

Why is that a disadvantage? It's one reason (amongst others) why Jim developed a round bar hanger for mechanical expansion anchors when there is a need to retreat from a high point on a route. Glue-ins do not present an issue in this regard.

The alternative is manky crap left behind on a hanger when people bail e.g.manky quick links that corrode shut and require a cordless angle grinder to remove.

For lower offs or abseil stations then obviously replaceable wear components should be fitted.

I think he was referring to people rapping or lowering through the eye of a glue-in normally, not as a way to bail. In Durango, we have a fair amount of glue-ins for TR anchors at one crag and they are getting worn from people rapping and lowering through them. Obviously this is not good because it is not easily replaceable. After several failed attempts, some of these anchors now have additional hardware to service the wear from descending, but several sets of hardware have been stolen off these glue-ins in the past. 


Also, I've used Jim's rod hangers to rap directly through the hanger and I would reccomend it unless you're bailing as it will twist your rope somewhat. If you're installing a rap station to be used for descending the route then you should add a 2 quicklinks or a quicklink and a rap ring. 
Guideline #1: Don't be a jerk.

Fixed Hardware: Bolts & Anchors
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