The Bolting End-Game

I'm just starting to think about getting into rebolting as I've noticed some suspect bolts at a crag I frequent. So yes, this is a total n00b question and I'm sure there is some other thread I could find somewhere on the Interwebs that would answer my question. If you don't want to answer, please for the love of Pete just don't.

Can someone help me understand what the results of bolting and rebolting are going to look like long-term? And how this results to decisions about what strategies to use now?

Here's what I mean--all bolts are temporary. None of them are going to last forever. Right? Does that mean our crags are going to look like Swiss cheese in a couple hundred years? Or are there best practices that allow for bolt holes to be reused indefinitely? I see people going to glue-ins. Can they be replaced using the same holes or are they just buying some longevity for the first rebolting only to require more holes later?

Read into these: climbtechgear.com/legacy-bo…

here's a thread discussing extracting bolts and reusing the holes. that should be the preferred method wherever possible. a few other threads that GreggerMan has contributed to detail their efforts in Eldo.

mountainproject.com/v/inexp…

Read everything on this page, then you will be the Bolting Master:

safeclimbing.org/education.htm

To address glue-ins specifically, if treated with respect (and not directly lowered through, wearing out the hangers), glue-ins have estimated life expectancies from 50 to 100+ years. This means less frequent replacement and fewer holes. Replacement of glue-ins can be achieved by grinding the hanger off and then core-drilling the hole, facilitating its re-use. I'm told this is relatively easy with the right tools but have not done so myself.

As noted above, extraction of mechanical bolts can be done, and while it can be a bit of a pain, the hole can often be re-used. Bolts that are easily replaced, like the legacy, are the way to go if mechanical bolts are preferred.

supertopo.com/climbers-foru…

But to answer your question I'm thinking swiss cheese eventually. Though by then we'll use suction cups or start climbing on Mars.

Derek DeBruin wrote:To address glue-ins specifically, if treated with respect (and not directly lowered through, wearing out the hangers), glue-ins have estimated life expectancies from 50 to 100+ years.

Sorry but no. There are many places around the world where 316 stainless glue-ins won't last 10 years due to corrosion. Thailand, Cayman Brac, Portugal, Hawaii, (many more) are good examples of places with severe corrosion.

Bolts that break in Thailand in 9 months break in Kalymnos in 9 years, so there's a spectrum of corrosive environments. We have yet to see a stainless bolt last 50 years in the Red, Rifle or any other area in the U.S. (and we may never see it) much less 100 years.

UIAA tests are in progress for several High Corrosion Resistant (HCR) steels and all are showing corrosion after only one year.

Only titanium glue-ins have an "indeterminant" lifespan which is the term metallurgists use when they don't want to say "forever". They are truly permanent.

Derek DeBruin wrote:This means less frequent replacement and fewer holes. Replacement of glue-ins can be achieved by grinding the hanger off and then core-drilling the hole, facilitating its re-use. I'm told this is relatively easy with the right tools but have not done so myself.

That often works. There's a good video on (both I think) the AF and ASCA websites on how to remove expansion bolts.

For glue-ins, you can use a torch to heat the bolt eye, soften/melt the glue, pull out the bolt, then re-drill, etc. There have only been "lab" tests of this method but it seems to work very well.

I've removed 2 glue-ins using the heating method. Took about the same time as removing rusted out Rawl 5 piece bolts. Neither were easy but with persistence came out in half an hour. The hardest part was making sure the hot torch didn't touch the rope. I used a long steel cable attached to a jumar attached to the rope, well over my head to add security just in case.

Even with all that heat I still had to use a long pry bar to just barely move it. Then reheat and repeat. Once I was able to get the eye out of the trench, I was able to spin the bolt. Things when quicker after that but still required effort up until the very last inch

On a side note, replacing bolts one for one is rebolting not retrobolting. The term retrobolting more accurately refers to adding additional bolts after the FA.

I also agree with John that 304SS is not going to last 50 - 100 years in most climates. I would say more like 5 - 50 years in most environments. Then again, the Gateway Arch was made in 1963, it's made out 304SS clad, and it's still standing today, but it is also maintained regularly I believe.

As far as replacing old bolts go, reusing the hole is preferable when possible. There are various ways to do this, all of which are documented online. When replacing bolts you should also use stainless steel, dont replace old carbon bolts with more carbon steel...

John Byrnes writes:
"Sorry but no. There are many places around the world where 316 stainless glue-ins won't last 10 years due to corrosion. Thailand, Cayman Brac, Portugal, Hawaii, (many more) are good examples of places with severe corrosion."

My apologies; I should have been more specific. Titanium will last seemingly forever; stainless steel will last a really long time absent maritime environments. The OP is in Utah, where I imagine a stainless glue-in can have a long and healthy life. Also, someone should tell the Access Fund. They seem to think glue-ins will last 200-500 years (second to last paragraph has the relevant bit): https://www.accessfund.org/educate-yourself/for-advocates/managing-fixed-anchors/best-practices-for-bolt-removal

There are ways to make old bolts almost disappear. Here is a picture I took of an old anchor I moved. I'd be pretty impressed if someone could find where the old bolts were.

Old anchor location. Good luck spotting the old bolts.

Obviously, not all rock is complex in pattern and texture but there is a right combination of glue and rock dust for any hole.

Thanks for all the info everybody!

20 kN wrote:I also agree with John that 304SS is not going to last 50 - 100 years in most climates. I would say more like 5 - 50 years in most environments.

I strongly disagree with this statement. If you are referring to sea cliffs or a seaside environment then your statement is correct. But, that is not the case for the majority of the climbing areas in the United States. I have been removing and replacing bolts for 28 years and have removed a lot of makes and models. Most of the bolts, especially the ones in hard rock are difficult to remove and I am referring to bolts that have been placed as far back as the 1940's!

Paul Helyiger, a professor of engineering at Colorado State University at Fort Collins, has been testing a lot of the Grade 5 carbon steel bolts(5-piece Powers/Rawls) that have been removed for replacement and even the ones displaying a lot of rust after almost 20 years still test out at 5000lbs shear for 3/8" diameter which is the rating from the manufacturer when new.

As I said before, in seaside environments all bets are off unless you are using titanium. But, in the climates found at the majority of the climbing areas in the USA stainless steel is going to last a long, long time and Grade 5 carbon steel(or better) will also last many, many years.

A similar discussion underway on ST
(and one of those participants,'couchmaster', owns a high tech fastener company).

Derek DeBruin wrote:John Byrnes writes: "Sorry but no. There are many places around the world where 316 stainless glue-ins won't last 10 years due to corrosion. Thailand, Cayman Brac, Portugal, Hawaii, (many more) are good examples of places with severe corrosion." My apologies; I should have been more specific. Titanium will last seemingly forever; stainless steel will last a really long time absent maritime environments. The OP is in Utah, where I imagine a stainless glue-in can have a long and healthy life.

While you are correct that maritime environments are the worst, inland stainless bolts can, and will, corrode as well. Limestone will cause corrosion. Sandstone is highly suspect but the jury is still out. Both are sedimentary rocks formed in seas (salt) and Utah has plenty of both.

Granite and other igneous rocks are better, but not immune. The least corrosive environment would be alpine granite because temperature plays a major role.

Derek DeBruin wrote:Also, someone should tell the Access Fund. They seem to think glue-ins will last 200-500 years (second to last paragraph has the relevant bit): https://www.accessfund.org/educate-yourself/for-advocates/managing-fixed-anchors/best-practices-for-bolt-removal

I've actually spoken at length to the AF on this issue. It takes time to make the official stuff change. Give 'em time.

Bruce Hildenbrand wrote: I strongly disagree with this statement. If you are referring to sea cliffs or a seaside environment then your statement is correct. But, that is not the case for the majority of the climbing areas in the United States. I have been removing and replacing bolts for 28 years and have removed a lot of makes and models. Most of the bolts, especially the ones in hard rock are difficult to remove and I am referring to bolts that have been placed as far back as the 1940's! Paul Helyiger, a professor of engineering at Colorado State University at Fort Collins, has been testing a lot of the Grade 5 carbon steel bolts(5-piece Powers/Rawls) that have been removed for replacement and even the ones displaying a lot of rust after almost 20 years still test out at 5000lbs shear for 3/8" diameter which is the rating from the manufacturer when new. As I said before, in seaside environments all bets are off unless you are using titanium. But, in the climates found at the majority of the climbing areas in the USA stainless steel is going to last a long, long time and Grade 5 carbon steel(or better) will also last many, many years.

It Depends (tm). The lifespan of any steel bolt depends on the rock type, annual rainfall, mean temperatures and the size, type of steel and design (glue-in or expansion).

Personally, I wouldn't place any non-stainless bolts in Colorado, and I know that the AF and ASCA agree.

rocknice2 wrote:I've removed 2 glue-ins using the heating method. Took about the same time as removing rusted out Rawl 5 piece bolts. Neither were easy but with persistence came out in half an hour. The hardest part was making sure the hot torch didn't touch the rope. I used a long steel cable attached to a jumar attached to the rope, well over my head to add security just in case. Even with all that heat I still had to use a long pry bar to just barely move it. Then reheat and repeat. Once I was able to get the eye out of the trench, I was able to spin the bolt. Things when quicker after that but still required effort up until the very last inch

That's good information! I hadn't thought about burning the rope. And another good reason to NOT recess the eye.

Do you know what brand/type of glue it was? What torch did you use? A common butane torch? What kind of rock?

John Byrnes wrote: While you are correct that maritime environments are the worst, inland stainless bolts can, and will, corrode as well. Limestone will cause corrosion. Sandstone is highly suspect but the jury is still out. Both are sedimentary rocks formed in seas (salt) and Utah has plenty of both. Granite and other igneous rocks are better, but not immune. The least corrosive environment would be alpine granite because temperature plays a major role. I've actually spoken at length to the AF on this issue. It takes time to make the official stuff change. Give 'em time.

Basalt is igneous and about as bad as it could possibly get for corrosion.

There goes John Byrnes touting his Ti bolts again. His bolts are fantastic for any type of coastal/salt water/corrosive environment. I am certainly not trying to sway anyone away from using his products, they are great. It is however hard to justify their expense for areas where they aren't necessary. Let's not leave out the fact that for the majority of areas (perhaps 90%) 316 SS is more than acceptable and a heck of a lot cheaper than Ti. It's reasonable to assume that areas like Red River Gorge should see 50 year lifespans out of SS glue-ins. Many carbon steel bolts here lasted 20 years after all... Most of the bolts I've replaced in RRG with a 20 year old carbon steel bolt and SS hanger show virtually no signs of corrosion on the SS hanger even when the 5 piece bolt was HEAVILY corroded. As previous posters have said it is possible to reuse glue-in holes with the grinder and core drill technique. John I know you have done a lot of research with this, so how long can we trust the epoxy used for glue-ins. I've heard manufacturers say 50 years, but is this a conservative estimate? Though the Titanium may have an indefinite lifespan can we say the same for the epoxy?

John Byrnes wrote: That's good information! I hadn't thought about burning the rope. And another good reason to NOT recess the eye. Do you know what brand/type of glue it was? What torch did you use? A common butane torch? What kind of rock?

Fixe bolt and Hilti re500. I don't remember what gas it was but I bought it in the local hardware store. It was a light weight canister (think aerosol can) but had a very hot flame.
I still trench the eyes, I think it's a must for that bolt in particular.

I replaced 20 year old Rwal carbon bolts with stainless hangers. The head and washers were covered in surface rust. Once extracted I could see that they were completely covered in surface rust. The threads between the bolt and cone had no rust. Oh and the cliff was Poke-O-Mooneshine in NY state. I think from this point the rust would have moved quite a bit faster. I would guess that they would be junk in another 10 years.

So stainless steel in this environment could last a very long time 50 years plus.

DrRockso wrote: I've heard manufacturers say 50 years, but is this a conservative estimate? Though the Titanium may have an indefinite lifespan can we say the same for the epoxy?

Epoxy has been around since the 1950s so we have had time to learn if it lasts 50 years or not. I suspect it does. Epoxy is extremely inert and it doesent seem to react with very much.

engineeringtoolbox.com/chem…