aking dream on Bukit Nenek Semekut, Pulau Tioman, has at least four generations of bolts:

  • those installed by the first ascentionists
  • intervening additions
  • ancilliary expansion bolts added in 2013, and
  • glue-ins added in 2013.

All these bolts are at different stages of degradation. We know of at least one party which bailed due to conerns around bolt integrity. We thought we’d document what we saw to give future parties more certainty.

1. First Generation Bolts (1998-2000)

All the bolts marked in the original topo show material signs of oxidisation, and appear to be combinations of carbon and/or galvanised steel. They have thin (6mm? 8mm?) threads, and seem variously RAWL and Pin-drive expansion bolts. Although none failed under our body-weight loads, we recommend proceeding with extreme caution – and not relying solely on these bolts in critical locations. We have replaced these bolts at crucial stances.

Additionally, the first ascentionists installed rivet ladders on pitches 3 and 5. These appear to be galvanised steel. All rivets held our body weight despite looking badly oxidised. We advise proceeding with caution and using these for upwards progress but not for protection. In the likely event that a rivet fails, we would encourage replacing it with a bat-hook placement.

2. Intervening Additions (2001-2012)

We encountered at least 20 bolts not marked on the original topo. Some appeared similar to the first ascentionists’ bolts – badly oxidised (carbon?) steel with thin threads. Most seemed to be stainless steel hangars and expansion bolts with 10mm threads. We suspect these to be 10mmx80mm SS304 similar to other equipment popularly used to bolt sports climbs in Malaysia in the early 2000’s. Some of these were starting to show mild discolouration, but others appeared fine. We used few of these bolts, but those we did use held body weight. Given the age and location of the bolts, we consider all these bolts to be candidates for failure through bulk corrosion, crevice corrosion or SCC.

(One of these bolts held our portaledge overnight – with multiple back-ups, of course!)

Many (if not most!) of these bolts are unnecessary and can be removed.

3. Expansion bolts (2013)

While our fixed lines were on the wall, another party ascended the route. They added a bolt at the end of P5 and another at the end of P6. Both appear to be stainless expansion bolts – we suspect SS304. Currently appearing reasonable, please consider the potential for crevice corrosion or SCC in these bolts.

4. Glue-ins (2013)

One of our expedition aims was to make the route safe not only for ourselves, but also of future ascentionists. We chose the best materials we could obtain – to ensure longevity and also to minimize further anthropogenic degradation of the rock.

All our additions were glue-ins with Hilti RE-500 (which is identifiable by its red colour). Glue samples were taken regularly, and all had tangibly hardened within 24 hours. We used three types of bolts:

Anchors on pitches 2 to 6 and 8 are equipped with one Thaitanium and one GPS10-100A4 bolt. Additional GPS6-100-A4 at anchors 2 and 4. The rappel descent is possible on double 60m ropes using trees (pitches 10,9 and 1) and the glue-ins installed.

Thaitanium protection bolts added on pitches 5 (x2) and 9 (x1).

Installing these bolts was time-consuming and costly. We request that climbers not top-rope or otherwise run a weighted rope through these glue-ins, as this increases wear on the bolt. Please only use for rappel anchors or clipped protection.

Legal disclaimer: We have no professional qualifications in inspecting or installing bolts – only experience. This information is no guarantee of the integrity of the bolts, and is intended only to inform future climbers of the materials used. Climbers are advised to inspect all bolts before use, and to use at their own discretion. When in doubt, avoid the bolt and use your own equipment. All bolts used at climbers’ own risk.

5. General Comments

Bolting of sports routes became accessible and practical in Europe starting in the late 1970’s, following Bosch’s introduction of the SDS drill; regular and popular bolting of sports climbs dates to the late 1980’s/early 1990’s. The clibming community has approximately 25 years’ experience of metal fatigue in climbing bolts.

In the 15 years since Scotty and Nick first explored Bukit Seminyak, the climbing world has learned much regarding bolt longevity – or lack thereof. In particular, failures of SS(304) expansion bolts in Thailand and Cayman Brac are well documented; there have been isolated cases of failures in South African and the Dominicaln Republic (and possibly further afield too).

Tropical maritime limestone crags have proven extremely corrosive. There is a general consensus that neither SS304 bolts nor expansion bolts are appropriate for such crags. Glue-in bolts appear to be preferred in these conditions, using either SS316 or Ti-1.4257- both with Hilti RE-500 glue.

Bukit Seminyak is the only tropical maritime bolted granite area that we are aware of. From our experience, the crag is exposed to persistemt maritime breezes with regular mist – which suggests a possibility of chloride build-ups. We witnessed intense corosion of carbon steel bolts as well as massive exfoliation on aluminum carabiners, and suspect there is a possibility of Stress Corosion Cracking here.

From this trip

  • Recommend that Bukit Nenek Semekut be considered a tropical marine environment – i.e. highly corrosive
  • Request that future development use, as a minimum, Class 1 HCR bolts for anchors, and Class 2 bolts otherwise
  • Recommend that all visiting climbers consider the UIAA advisory on tropical marine environments
  • Suggest that a fund be established for the purposes of financing safer bolts on Pulau Tioman

Note: we are not materials engineers, and are not professionally qualified to certify any safety apparatus. This advice stems only from our personal experiences and reading

An interesting article has been recently publish on climbing.com on climbing anchors and corrosion.

6. Further comments on Waking Dream

The second ascent added many bolts to the route. Having repeated the route and witnessed the bolting first-hand, here are a few comments:

  • We see no evidence (guarno, nests, feathers, etc) of birds above the catwalk, and view the bolts up to the pendulum as a pointless distraction from the original line
  • We find the crack leading to the Alcove as safely protectable on aid and free, and consider the bolts here redundant
  • We thought the excessive bolts on P5 reduced the crux into a bolt ladder

Other than anchors, we only replaced three bolts on the route:

  • One (new) bolt next to the rivets on P5, where a rivet failure would result in a dangerous fall onto the belayer
  • Replaced one FA bolt on P5 before entering the aid crux, which is otherwise unprotectable
  • Replaced one FA bolt on P9 where a fall would be dangerous/deadly, and which is otherwise unprotectable.

We encourage and subsequent parties to remove the unnecessary bolts. Unfortunately we did not have time to do this ourselves.

7. Other areas in Tioman

We don’t have any information on the bolts used on the Nipah and the Juara sector. And we don’t know what is the current status of these bolts. From some reports (please treat this carefully):

  • In Nipah, bolts are older than 5 years old and show material signs of oxidisation.
  • In Juara, Karang Balau, “bolts look very recent and in good condition as of 2013”. Please consider the potential for crevice corrosion or SCC in these bolts.
  • In Juara, headland cliffs,  bolts show material signs of oxidisation.


The Dragon’s Horns on Tioman Island, Malaysia, Part4: bolt status
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