rusting
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Depends on how long you let it sit... a lot of those plastic housings trap and hold water, and if the knife sits in there for a long time you can start to see some rust. I take my knife out to let it dry by itself.
i got this nice http://www.cressi-sub.it/prodotti.asp?lan=uk&id_c=10&id_p=220 Lama Apnea. It was in the water for 2 dives and, after i pulled it off, has touches of rust all other the place...
Jozefrh
Guest
Hi there,
All SS will rust if it is left in contact with mild steel or iron. The iron molecules suspended in the water will be enough to get the SS to rust. You can clean it back up with particular acids but it will never have that new finish again. Making sure the knife is fully dry before storage is your best option for the next blade. To clean this one use CLR or naval jelly then brush with steel wool. apply a coat of oil.
I watched one of my dive knoves go to rust in the same manner.
Joe
All SS will rust if it is left in contact with mild steel or iron. The iron molecules suspended in the water will be enough to get the SS to rust. You can clean it back up with particular acids but it will never have that new finish again. Making sure the knife is fully dry before storage is your best option for the next blade. To clean this one use CLR or naval jelly then brush with steel wool. apply a coat of oil.
I watched one of my dive knoves go to rust in the same manner.
Joe
Once you get the rust off, before putting it away, put a nice coating of silicone on it. I rarely use my knife, almost aways forget to rinse it, but the coating of silicone keeps the water off it and the blade is rust free.
airsix
Contributor
One of my other hobbies is making custom pocketknives so I have a little background in corrosion resistance and corrosion prevention in tool steels (carbon and stainless).
What' the best knife? The one the NEVER rusts, or the one that can really hold and edge? The one that is really tough and won't chip or break a tip? Unfortunately you can't wrap all those features into the same blade. It's always a compropmise. The best performing steels do not have the greatest corrosion resistance. So you have to find the compromise between adequate corrosion resistance, and adequate toughness/edge-holding. You have to give up some of one to get more of the other. I'd rather have a high performance blade that requires a little maintenance than a highly-corrosion-resistant blade that performs poorly.
One of the ways a knife-maker improves corrosion-resistence on a blade is to reduce the surface area by making the finish very bright (polished). This increases resistance to corrosion, but it also makes it difficult to coat the blade with something like silicon. I'd recommend using a paste wax instead. Post-dive you can wash and thouroughly dry your knife and then wipe it down with the waxed cloth and it should stay bright forever.
If you do get rust spots treat them as soon as you can. You can use Naval Jelly from an autoparts store to neutralize the rust. Then use progressively finer grits of sandpaper on a block (like a paint stir stick) to restore the fine finish. Use wet-dry paper from and autoparts store and try progressive grits from 400 to 2000. Use baby-oil to keep the paper from clogging. Word of caution - restoring the finish with sandpaper as described is VERY labor intensive. Expect to spend some time on it to get it right.
Hope that is useful.
-Ben M.
What' the best knife? The one the NEVER rusts, or the one that can really hold and edge? The one that is really tough and won't chip or break a tip? Unfortunately you can't wrap all those features into the same blade. It's always a compropmise. The best performing steels do not have the greatest corrosion resistance. So you have to find the compromise between adequate corrosion resistance, and adequate toughness/edge-holding. You have to give up some of one to get more of the other. I'd rather have a high performance blade that requires a little maintenance than a highly-corrosion-resistant blade that performs poorly.
One of the ways a knife-maker improves corrosion-resistence on a blade is to reduce the surface area by making the finish very bright (polished). This increases resistance to corrosion, but it also makes it difficult to coat the blade with something like silicon. I'd recommend using a paste wax instead. Post-dive you can wash and thouroughly dry your knife and then wipe it down with the waxed cloth and it should stay bright forever.
If you do get rust spots treat them as soon as you can. You can use Naval Jelly from an autoparts store to neutralize the rust. Then use progressively finer grits of sandpaper on a block (like a paint stir stick) to restore the fine finish. Use wet-dry paper from and autoparts store and try progressive grits from 400 to 2000. Use baby-oil to keep the paper from clogging. Word of caution - restoring the finish with sandpaper as described is VERY labor intensive. Expect to spend some time on it to get it right.
Hope that is useful.
-Ben M.
Your knife is probably made of 420 stainless... note: "stain less" - not "stain proof"
316 stainless won't rust - but it's soft. Like a butter knife in your drawer at home. Never rusts, but you can lean on it and bend it in half.
The best solutions I've seen are Titanium if you want to spend the money, or UK has a new alloy called hydroalloy which has the hardness of 420, the stain resistance of 316, but less cost than titanium. http://scubatoys.com/store/detail.asp?PRODUCT_ID=BlueTangH
Tusa also has a very sharp, very impressive knife that is guaranteed not to rust: http://scubatoys.com/store/detail.asp?PRODUCT_ID=FK230
I'll spend the money to get one that doesn't rust... to keep up one of the others is too much time invested... If you pay yourself 5 bucks an hour for your time of cleaning, drying, oiling, putting on bandages on fingers after cleaning... you'll be ahead on just getting one that doesn't rust and holds a good edge.
316 stainless won't rust - but it's soft. Like a butter knife in your drawer at home. Never rusts, but you can lean on it and bend it in half.
The best solutions I've seen are Titanium if you want to spend the money, or UK has a new alloy called hydroalloy which has the hardness of 420, the stain resistance of 316, but less cost than titanium. http://scubatoys.com/store/detail.asp?PRODUCT_ID=BlueTangH
Tusa also has a very sharp, very impressive knife that is guaranteed not to rust: http://scubatoys.com/store/detail.asp?PRODUCT_ID=FK230
I'll spend the money to get one that doesn't rust... to keep up one of the others is too much time invested... If you pay yourself 5 bucks an hour for your time of cleaning, drying, oiling, putting on bandages on fingers after cleaning... you'll be ahead on just getting one that doesn't rust and holds a good edge.
FredT
Guest
Quick answer:
Go buy a 2 liter bottle of Coca-Cola Classic. Find a non-metallic pan large enough to hold the ENTIRE knife. Cover the knife in CCC. Allow this to set overnight. The rust will be gone. Chemical "seed" where the rust started will also be gone. Finish should be unchanged.
Go buy a 2 liter bottle of Coca-Cola Classic. Find a non-metallic pan large enough to hold the ENTIRE knife. Cover the knife in CCC. Allow this to set overnight. The rust will be gone. Chemical "seed" where the rust started will also be gone. Finish should be unchanged.
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