Small knife rust resistance experiment

J-sews · **Reply #60 on:** May 20, 2011, 05:50:32 AM

This has been the best blade/corrosion test ever.

Sea Monster · **Reply #61 on:** May 20, 2011, 10:00:57 AM

Very nice test.

665ae · **Reply #62 on:** May 20, 2011, 11:05:48 AM

I'm no science major... But wouldn't the movement of water (tide) hinder the formation of rust on the surface of the blade? (I could be way wrong...)

Sea Monster · **Reply #63 on:** May 20, 2011, 11:12:31 AM

Quote

I'm no science major... But wouldn't the movement of water (tide) hinder the formation of rust on the surface of the blade? (I could be way wrong...)

Rust needs air, as well as salt and water, so putting it in the tide is necessary to give it all three magic ingredients.

HawkeyX · **Reply #64 on:** May 20, 2011, 09:13:05 PM

So for the grand finale, how did they clean up...
(again, sorry for quality, pics taken late at night under lamp)

So not bad overall, but the once invincible 'fresh' blade really didnt like that line being tied around its pivot, and the other blade never fully recovered from the rust at the tip.

Considering how little the 'fresh' blade rusted until late in the play, its quite disturbing how bad that pivot rust got. I dont think it backs up it being because its a high wear/friction zone however, since as mentioned the steel is the same throughout, its not coated + the other pivot was fine. Also, largely neither blade got much rust on the sharp edge which is wear point. Having the line on it without a doubt acted as a cover of sorts, perhaps keeping the salt content constantly on the blade throughout the tide cycles. The soak test at home didnt affect that blade, but did the other to a larger degree than its time in the ocean...

So a salute to these two little blades, they have come away scared, but not dead!

jatrias · **Reply #65 on:** May 22, 2011, 04:36:00 AM

thank you for posting the experiment!

Huntsman · **Reply #66 on:** January 14, 2014, 11:12:01 AM

Quote from: HawkeyX on April 17, 2011, 12:30:12 PM

I chose a place you can only access at low tide, but who knows, a scavenger may find them and take them.
(Image removed from quote.)
So...its either an update next week, or...

Hey Hawkey,
Some one posted a link to this thread in a more recent post - So I enjoyed reading about your very interesting experiment. Nice one - Well done.
I think the next test would be to leave them in the sea for six months - then to see what happends!!

I worked in Auckland for a few months last year - and it was very nice to see Rangitoto framing the background of your experimental site

For anyone reading this thread who does not know Auckland Bay - Rangitoto is the flat, conical (is that a contradiction) island in the background of the shot.
And yes it is volcanic - And what is really interesting is - If Hawkey had taken this shot 600 years ago the island would not have been there!!