Any info on these hangers??

Hi! I have had these petzl hangers for awhile now (when I bought a used box of climbing holds I found 7 of them at the bottom) and I've been wanting to get into bolting. I've been learning and practicing a bunch and I'm almost ready to go out and bolt. The hangers are in really good shape (besides a little brown paint on them) but I need to make sure they are stainless steel. They are only slightly magnetic, (the magnet doesn't stick but I can feel some attraction)  and I have been reading articles that contradict each other about whether or not SS is magnetic. They are not shiny and I don't believe they are zinc plated. I cant find any stamps that say SS or anything on them. The bolts also show no signs on rust but to bare slight scratches on where you would bolt them so I know they have been placed before. My question is if anyone knows if these are stainless or not, I would love to use them before having to buy some. *The holds they came with where definitely placed on a outdoor wall* 

All I know is scrap yards won’t pay stainless price if a magnet sticks to it. 

Maybe lesser quality stainless is magnetic or is it possible that cold or hot worked stainless becomes magnetic? No clue on that part just thinking out loud. 

and I have been reading articles that contradict each other about whether or not SS is magnetic.

"Stainless steel" is a general and vague term. It can be used to mean any steel that is more corrosion resilient than mild carbon steel. There are literally hundreds of types of stainless steel, maybe more. However, when you consider how much of each type is produced only a few alloys make up the large majority of these stainless steels. The most common are the 300 series specifically 304 and 316 SST. The 300 series is an Austenitic stainless steel, these are not magnetic.

Other types of steel like the 400 series are Ferritic stainless steels (409, 430), these are magnetic.

There are many other types of stainless steel, I cannot comment on whether each is magnetic or not as I am not familiar with them: Martensitic stainless steels, Duplex stainless steel, Precipitation hardening stainless steels, etc.

For your reading pleasure:

https://en.wikipedia.org/wiki/Stainless_steel#Stainless_steel_families
https://en.wikipedia.org/wiki/SAE_steel_grades

Oh, and even 304 is slightly magnetic. Like 100X less than normal carbon steel. I have used a big rare earth permanent magnet with about 50 lbs of pull (on mild steel), with a 304 SST disk it can barely hold its own weight, maybe .5 lbs.

They don’t look like they are zinc plated, they do look to be stainless when compared to the stainless hangers I use.  

I bet those Petzl hangers are from back when they were 304. Newer ones that look like that are 316 but have date codes - however I'm not sure if there were 316 hangers before they started the date codes, there could well have been. 304 are slightly attracted to magnets, 316 very slightly.

The FFME is a big French climbing/mountaineering organization.

Greg Barnes wrote:

I bet those Petzl hangers are from back when they were 304. Newer ones that look like that are 316 but have date codes - however I'm not sure if there were 316 hangers before they started the date codes, there could well have been. 304 are slightly attracted to magnets, 316 very slightly.

The FFME is a big French climbing/mountaineering organization.

Quick question Greg. Were these ones engraved FFME used widely in the US? I found a mystery bolt ladder of these things. I do know it dates circa 2000s. Would one assume it was European tourists or would Americans have been using FFME-engraved hangers around that time? 

Won't know without XRF at a minimum but current Petzl stainless steel hangers are 316L and marked accordingly. 

Any 2 to 3 digit number beginning with a 9 on the rear of the hanger? E.g. 97?

The mild magnetism is likely to be the result of manufacturing (because of the change in grain structure from austenite into martensite) not because of the grade itself. Austenitic stainless is generally not magnetic and becomes magnetic once worked by a manufacturing process. I can take a magnet to bolts from different anchor manufacturers and some are mildly magnetic while a select few made from 316 are not.

I had several hangers with the same appearance as yours analysed in a materials lab under the UIAA Safecom / Crag Chemistry project and they were similar to 304 grade and contained a high amount of Marstenite grain:

"All hangers you supplied are made of 17Cr-7Ni stainless steel. Most probably, it is EN 1.4568 (17-7 PH), a precipitation hardening grade with high strength and hardness a somewhat worse formability. In view of corrosion resistance, it is similar to 304".

A light pull from a magnet is typical of many austenitic stainless steels (304, 316). 

Duplex steels, while often magnetic, aren't super common outside of some specific manufacturers and areas.  400 series includes both ferritic and martensitic grades are even less common. 

If it is plated low alloy steel it will likely ping onto a magnet with some snap. 

Francis Haden wrote:

What’s the story behind the cracking on that hanger?

a beach wrote:

What’s the story behind the cracking on that hanger?

Crevice corrosion initiating chloride induced, low temperature SCC in the hanger.

Coastal sport climbing crag in Hong Kong.

Brian Campbell wrote:

0/10 would whip

A local climber had the same opinion regarding the state of the hangers, took a short lead fall, snapped the hanger and hit the deck. His belayer took a fair share of the impact too.

Amazing what rust will hide.

Check if the bolt hole they are 3/8” or 1/2”. They look like the 1/2” I use at anchors sometimes. 

Francis Haden wrote:

Won't know without XRF at a minimum but current Petzl stainless steel hangers are 316L and marked accordingly. 

Any 2 to 3 digit number beginning with a 9 on the rear of the hanger? E.g. 97?

The mild magnetism is likely to be the result of manufacturing (because of the change in grain structure from austenite into martensite) not because of the grade itself. Austenitic stainless is generally not magnetic and becomes magnetic once worked by a manufacturing process. I can take a magnet to bolts from different anchor manufacturers and some are mildly magnetic while a select few made from 316 are not.

I had several hangers with the same appearance as yours analysed in a materials lab under the UIAA Safecom / Crag Chemistry project and they were similar to 304 grade and contained a high amount of Marstenite grain:

"All hangers you supplied are made of 17Cr-7Ni stainless steel. Most probably, it is EN 1.4568 (17-7 PH), a precipitation hardening grade with high strength and hardness a somewhat worse formability. In view of corrosion resistance, it is similar to 304".

I found a number stamped on the back, its marked 98.3 for the 12mm(1/2) size, and 98.4 for the 10mm(3/8)

Zach Greene wrote:

I found a number stamped on the back, its marked 98.3 for the 12mm(1/2) size, and 98.4 for the 10mm(3/8)

Finally 'allowed' to reply  

Based on the year and month stamp, my guess (and only a guess without analysis) is that the material is closer to 304 stainless more so than anything else e.g. 316.

Zach Greene wrote:

Hi! I have had these petzl hangers for awhile now (when I bought a used box of climbing holds I found 7 of them at the bottom) and I've been wanting to get into bolting. I've been learning and practicing a bunch and I'm almost ready to go out and bolt. The hangers are in really good shape (besides a little brown paint on them) but I need to make sure they are stainless steel. They are only slightly magnetic, (the magnet doesn't stick but I can feel some attraction)  and I have been reading articles that contradict each other about whether or not SS is magnetic. They are not shiny and I don't believe they are zinc plated. I cant find any stamps that say SS or anything on them. The bolts also show no signs on rust but to bare slight scratches on where you would bolt them so I know they have been placed before. My question is if anyone knows if these are stainless or not, I would love to use them before having to buy some. *The holds they came with where definitely placed on a outdoor wall* 

Those look a lot like several hangers I've pulled off routes down here in TX that were probably around 20-25 years old. Rust was from a PS 5 piece washer - I used some lemon juice and Barkeepers to polish them back up and will re-use at some point.  They looked brand new after the cleaning.

I've placed those hangers in the past:

Believe I picked them up from someone in Europe.  I think Petzl made a bunch for the Fédération Française de la Montagne et de l'Escalade.  I've seen some of their outdoor testing rock blocks that they do aging and pull tests on in France.  Extras were let go is my guess.  I had a pile of them from somewhere.  

I think Greg is right...those are probably 10 or 15 years old and most likely 304 series stainless.

mattm wrote:

Yea that looks exactly like the ones I have.

Thank you everyone for the awesome info and help!