Rust on washers

Can I assume all 3 of these washers are not stainless? I plan to swap the washers out on my next visits to the routes but am curious what is causing the rust.

The B length bolt looks like it and the washer are plated carbon steel. The nut may be stainless? You see crazy things sometimes.

On the D legth bolt the rust spots are on small dings on the washer that could have come from a steel tool?

The top picture looks to be all SS, the washer just got some dings possibly?

The bottom two shots looks like only the hanger is SS.  

What is the general environment like where these were placed? Wet, dry desert, high alpine?

These bolts are all located at roughly 10,000ft and are on anchors. I should attached a magnet to the outside of my pack for quick metal ID while on a route.

The first “D” bolt should be all stainless and has been in place for 1 year. I don’t know how the washer  was damaged but it’s easy to swap out.

The second and third “B” bolts are 14 years old, maybe a bit less? Is the rust on the third washer concerning enough to pull that bolt?

I’m inclined to remove the washers on the “B” length bolts to get more of the threading exposed. Any objections to that?

Stainless obviously would be better but I bet dollars to donuts those two bottom bolts will be in pretty good shape when you pull them.  

Anna, you've certainly been busy with rebolting this summer! 

The upper photo: Bolt length "D" (3" to <3.5"), has a stainless steel flat washer. Someone struck the washer, multiple times, with a non-stainless steel hammer. That damaged the chromium oxide passivation layer and introduced iron particles. The result is the rust that you see on the washer. The best solution is to swap for a new washer. Or, do nothing, as the washer is not structural and will probably last 30+ years.

Middle photo: The washer appears to be zinc plated carbon steel with mild rust. The best solution is to swap for a thinner SS flat washer. With the hanger off, hammer or chisel away at the tiny crystals and flatten the seat for the hanger. It seems that many or most installers don't prepare a seat for the hanger to sit flush against the surface of the rock, as in this case. I never understood that, it seems lazy to me. That should provide 2 threads above the nut for this bolt when you are done. Note that the bolt length "B" = 2" to < 2.5"  That bolt has very little embedment depth. Subtracting .75" for the thick Fixe hanger, flat washer, nut, and protruding end, that bolt is only 1.25" to <1.75" deep. Subtract another 1/4" from the bottom of the wedge/cone to the point of contact for the expansion action and the "effective depth" is 1" to <1.5". Call me spoiled from using rotohammers, but I don't consider that to be an adequate depth. In my opinion, responsible bolting has a minimum 2" embedment depth in hard rock. 

Bottom photo:  Clearly a zinc-plated carbon steel washer. The sacrificial zinc has mostly expended its usefulness. Replace with a thin SS flat washer. Prepare the mating surface of the rock under the hanger. If there is visible rust contamination of the wedge anchor, the rust may be cleaned and re-passivated with "Bar Keepers Friend". Keep that away from nylon ropes, etc. as it contains oxalic acid.

The length codes may be helpful to have. Overall length of anchor (source Hilti) Length Identification System (standard in construction industry). My comments added for discussion purposes only; not to be considered as advice due to the many variables in nature and materials.

A = 1.5" - up to, but not including 2" (not suitable for climbing)

B = 2" - < 2.5" (questionable for climbing purposes, some manual drillers may disagree? Hard rock only)

C = 2.5" - < 3" (adequate for hard rock)

D = 3" - < 3.5" (a frequent favorite when power drilled)

E = 3.5" - < 4" (inspires confidence for belay/rappel anchors)

F = 4" - < 4.5" (medium-hard rock)

G = 4.5" - < 5" 

Careful on unscrewing the nuts - you may want to file the edge of the end of the bolt before unscrewing, so that you don't have thread damage from the squished-out end of the bolt (thread damage on the inside of the nut). Hard to tell from these photos whether that will be a problem. First looks fine, second might be fine, third might need some filing?

I'm guilty of placing B length 3/8" stainless wedge bolts, all hand drilling good granite, but as ClimbBaja says, they are definitely minimalist for bolt length. Drilling a good hole and placing on slabby rock where high fall forces are unlikely means they're probably fine - I would often place one at an anchor then one stainless 5-piece.

Greg, I wouldn't say "guilty" of placing "B" length, nor lazy. You're out there doing the hard work, amigo. Bosch spoiled me in the late 80s with an additional 10 seconds to drill that extra inch of depth! There is one rule about power drilling in Baja: "Don't leave home without one!"

I just looked at Hilti's building code specs on the KB3 wedge anchor, and learned that they have an "effective minimum embedment" symbol "hef". That is what I mentioned in my post above about subtracting an additional .25" due to the bottom part of the cone (Hilti identifies that cone as the "mandrel"). Figure 2. shows the hef. Table 3. shows the effective min. embedment for the 3/8" SS KB3 is 2"    https://icc-es.org/wp-content/uploads/report-directory/ESR-2302.pdf 

The bolts in my photos are within a wilderness boundary and were handdrilled. They are all anchor bolts in good granite, none are protection bolts.

That's a good idea to bring a file Greg. I wouldn't have considered packing one for a washer swap but I can see now that it might be needed. These are essential anchor/rappel bolts that have to be in working order after I leave so I'll bring a bolting kit too in case things so sideways.