Petzl Croll L - cam not engaging?

[mikem]

According to this comparison (US), the spring tension on Croll L is lowest of any chest device &:

A lower spring tension will create less drag as the ascender is advanced up the rope, but it may also fail to grab the rope as positively

See bottom of: https://www.derekbristol.com/ascenders

So you do need to compare it to another (modern) L - although it should be about 3x the pantin

 

[Steve Clark]

Crude test - chopstick on some kitchen scales. Upside down. No peer review.

'Weight' needed to open the cam to about 10mm :

Pantin - 125g (before the 2nd spring comes into play)
New Basic - 375g
Newish Croll S - 325g
Newish Ascension - 380g

Newish Croll L I had the problem with - 170g

Seems to agree with how it feels. But, as above, it may be designed to be like this. It's not getting stuck in any way now when it's clean.

 

[mikem]

That test won't mirror the tension results in graph, but the L should be much closer to the figure for the S, than the pantin!

 

[Steve Clark]

Took it into Inglesport for them to look at today. Thoughts seem to be be it's similar in spring tension to a normal new Croll L and not obviously defective. I can only conclude it must have been some mud or grit between the cam and the frame holding the cam back from the rope slightly. I've not managed to repeat the problem now it it's clean.

Will keep a close eye on it and carry a spare.

 

[Ian Ball]

What diameter rope were you using?

 

[Steve Clark]

10mm. Old-ish club rope, but not heavily used. Clean when rigged. Two muddy folks climbed before me.

I?d worn the Croll as far as Fall pot and continued to near oxbow corner and back via the high level route. There was a fair bit of mud caked on the front of the suit.

I can only think there was something behind the cam or there was a fold in the oversuit pressing on the back of the cam catch adding some friction.