Replacement of springs in a cheap knife.

[ged]

I have a stainless folding knife/shackle key/rope spike which was given to me as a present. It wasn't expensive, but I became very comfortable with using it when sailing. It had everything that I needed, and over the years it's been important in resolving a couple of tricky situations involving ropes. So I'm fond of it.
Sad git.

One day I decided to give it a wash to clean out all the salt from the innards. I hung it over a radiator in the house to dry overnight with the blade and tools partly open so that as little water as possible was trapped between the parts.

In the morning, the springs which hold the tools open and closed were all cracked, and the whole tool is now useless. The people at the shop which supplied it were unhelpful. Rather than throw it away, I've kept it in my desk drawer at work for years, hoping that one day I'll find the time to repair it. I now think that I will never manage to justify the time.

It seems like this might be one place to find someone who can fix it. I have all the parts of the springs but they will need to be replaced with something more durable than the cheap originals. It's riveted together with a few stainless rivets, similar to this probably slightly more upmarket 'Ibberson' model:

http://www.shop4leatherman.co.uk/sailing_sailors_yachting_knife.html

I could probably replace it for little more than a tenner, but I don't want to do that, I have several other similar tools for sailing anyway. I just want this one fixed. I wouldn't expect the cost of the repair to match the cost of a replacement.

Any takers?

I'll expect you to be able to demonstrate your competence before entrusting you with the tool.

 

[bushwacker bob]

The cost of repair will easily double the price of a new one. The springs could be remade but as its a sailing knife you will probably need stainless steel at twice the price of O1 steel, then hardened without warping. The stainless rivets would need to be drilled out with precision to avoid scratching the scales and the whole lot reassembled. It can be done but I'd suggest contacting a proffesional penknife maker such as Russell White or Steven Cocker on British Blades.

 

[ged]

The cost of repair will easily double the price of a new one. The springs could be remade but as its a sailing knife you will probably need stainless steel at twice the price of O1 steel, then hardened without warping. The stainless rivets would need to be drilled out with precision to avoid scratching the scales and the whole lot reassembled. It can be done but I'd suggest contacting a proffesional penknife maker such as Russell White or Steven Cocker on British Blades.

Yes, I'm prepared for the shock, and yes, the new springs will need to be stainless. I could have bought another identical model for the springs, but no doubt they would have the same problem, so a repair done like that would probably be a waste of time -- I'd still have had to drill out the rivets and replace them. The scales already show signs of use but I can easily remove the rivets myself without damaging them, and the scales can easily be polished. The difficult bit is going to be making decent springs. I'm just not set up for stuff like that so it would take me days at least, more likely weeks, and I'd have no idea how they'd turn out at the end of it! Thanks very much for the names, I'll contact them.

 

[_scorpio_]

stainless steel is not rust proof, just rust resistant, so if it stays covered in salt water for a while it will still rust and fall apart.

 

[ged]

stainless steel is not rust proof, just rust resistant, so if it stays covered in salt water for a while it will still rust and fall apart.

That's why I washed it.

Stainless steels vary greatly in their resistance to rust. The 'household' cutlery grades are at the lower end of the scale of rust resistance because 18/8 or 304 (or whatever it is) is on the cheap end of the scale of material costs. Low end stainless isn't usually very good in strong chloride solutions, especially if there's a low oxygen concentration because stainless is stainless by virtue of a hard layer of chromium oxides formed on the surface almost immediately the oxygen in the air reaches the steel. If you put stainless steels in a wet, low-oxygen environment (like a couple of stainless plates bolted together, or the springs and scales on my Sailor's Friend) then you can have problems with what's called 'crevice corrosion'. Stainless steels commonly pit in chlorides. Sea water is about 3.5% sodium chloride and carries less oxygen than fresh water. Oh dear.

Some stainless isn't _very_ corrosion resistant because that's not the first priority. Many knife blade materials come into that category, things like taking a keen edge, toughness and wear resistance might be much more important. It's horses for courses and it often has to be a compromise. There's are links to much more information in the FAQs in this forum.

Never mind, corrosion takes a while to get established so if you're careful you can keep it at bay even on cheap cutlery like mine. Most sea-going stainless is 316, which is a lot better in salty atmospheres but not very good for tools. I work with it quite a bit, I think of it as the metallic alternative to plasticine.

 

[_scorpio_]

...if you say so then
is 316 going to make a good spring though?

 

[ged]

...if you say so then
is 316 going to make a good spring though?

Most unlikely! I wasn't planning to use it for that, I use 316 to make yacht fittings.