It depends. Whats the type of rock, breaking strength of the nut, quality of the placement and length of the fall? Also, who is belaying me and is it on the first pitch or is the belayer anchored in?

Any chance you'd have stats on failure rates or test results. (or links obviously). Thanks.

The biggest size of micro is stronger than the smallest regular nut and the smallest of anything is for aiding climbing.

No. Even the smallest micros get used for trad protection.

Cruxes on quite a few classic climbs at Arapiles are only protectable on micros. RPs were made specifically for these sorts of climbs.


(Of course European regulations mean anything less than 5kN is designated Aid only.)

No. Even the smallest micros get used for trad protection.

Cruxes on quite a few classic climbs at Arapiles are only protectable on micros. RPs were made specifically for these sorts of climbs.


(Of course European regulations mean anything less than 5kN is designated Aid only.)

I used and sort of fell on a 1 rp once. I wouldn't want to do it again though.

I just bought a couple of BD micros but usually have had HB brass offsets. So now I'd like to know more since I can make the choice.

IME, on shallow placements, the hard BD micros tend to skitter off hard crystals, allowing the placement to fail, where the softer brass would deform around the crystal and stay in place.

GO

That seems in keeping with what I've previously heard. In the other case, a harder piece will burrow into the softer rock somewhat (assuming it doesn't blow). I'm still a little confused on the disadvantage of softer piece in softer rock though. Too hard to extract?

I know you've just bought the BD micros, and I hate to rain on the parade, but to be perfectly blunt, I've never yet seen a placement where I'd rather have a BD Micronut.

The only thing I can think of is a situation in which you've got a perfect bottleneck placement in good hard rock, but imperfect contact with the rock, and the possibility of taking a big whip on it. In that case, the extra hardness might keep the piece from deforming and pulling out of the rock. Can't say as I've ever been in that position, though (nor would I want to be, lol).

GO

It's funny, I have seen the same statements and arguments surrounding micronuts for years yet I rarely see any factual data, just anecdotal evidence.

Manufacturers are pretty tight-lipped about the hardness of the materials they use. The only reference I have come across is a Clyde Soles article in Rock and Ice #66 back in 1995. He sent out batches of nuts to a lab to determine the Rockwell rating. The results are below.

BD Stoppers, Aluminum, 56.
BD Micros, Copper/Iron, 41.
HB Offsets, Silicon Bronze, 25.
Pacific Crossing RPs, Brass, 51

As you can see, the BDs are actually softer than the RPs, and both are softer than a standard BD aluminum nut.

In the end, effective use of micronuts is much more dependent on the quality of the rock and the placement, and not the hardness of the material.

I know you've just bought the BD micros, and I hate to rain on the parade, but to be perfectly blunt, I've never yet seen a placement where I'd rather have a BD Micronut.

The only thing I can think of is a situation in which you've got a perfect bottleneck placement in good hard rock, but imperfect contact with the rock, and the possibility of taking a big whip on it. In that case, the extra hardness might keep the piece from deforming and pulling out of the rock. Can't say as I've ever been in that position, though (nor would I want to be, lol).

GO

For each type of micros there is a "as good as a micro placement can get" for them depending where you climb. I bet in most if not all cases, they are all about fit and have little to do with metallergy (just like other gears). If sandstone or whatever rock is indeed "soft" then I doubt if any small micros would be useful. So talk with your local. Generalization claiming about one type over another is useless.