Technical sak questions

[Jim158]

Hi
 I am a new member of the forum and a fan of the saks
 I also am a professional technician , with excellent  normal tools. Knipex pliers of several types , facom screwdrivers, etc. I am used to use my tools with force.
 I dont expect my climber and my rangergrip 57 to tolerate similar strength as my normal tools. But i am looking for methods to improve their structural strength
 So
 Would changing the brass rods with stainless steel screws improve the strength of my 91mm and 130mm saks?
 Using steel scales would produce more solid saks?
 Perhaps even replacing some factory  liners with stainless steel liners?
 I am willing to accept a weight increase. In comparison with my professional tools that i carry every day, every minute the weight of the victorinox is a joke.
  The use of screws certainly produces an easier to disassemble tool. On a later stage i would like to try a better steel quality main blade for my climber. What blades are familiar choises for such a task
 Thanks in advance

[Enginears]

Welcome to the forum Jim.

I think particularly in this section you will find SAKs that replace the liners with steel, the scales with Ti, Al, and steel. I personally have used steel rod for some of my mods. The question is did those things really make tool failure less likely? Probably, maybe.

I have watched a lot of destructive knife testing and hard use testing on Saks and tools. The softness on the SS found on Saks seems to prevent some of the catastrophic brittle failures of other blade steels. (Like when the Dutch Bushcraft Knives Channel on youtube tested the MKM Sak-a-like that has titanium scales and an M390 blade and it broke.) Where you can find some “hard use” type test videos of Saks that also baton and don’t fail that way.

That said in my younger years I had a 1 layer Sak with a phillips backtool and I completely destroyed it when the pin and liners all bent. Stronger pin, liners, scales would have allowed me to keep torquing until the SS failed and rounded off.

A lot of people have been swapping in Spyderco blades into their Mods, which come in different steels that you may prefer. In the mean time you could also just run the SAK as is and wait to see where it fails before making changes. If you poke around the “show me your sak mods” thread you will find some of those mods I mentioned.

[powernoodle]

Welcome, Jim.      

[Cleanser]

I think pivots offer minimal strength improvement unless you used 1/8th pivots and full length screws for everything. 2.25 and 2.5mm pivots are pretty weak.

Pivots would be easier to fix everything in case of failure.

[Jim158]

Welcome to the forum Jim.

I think particularly in this section you will find SAKs that replace the liners with steel, the scales with Ti, Al, and steel. I personally have used steel rod for some of my mods. The question is did those things really make tool failure less likely? Probably, maybe.

I have watched a lot of destructive knife testing and hard use testing on Saks and tools. The softness on the SS found on Saks seems to prevent some of the catastrophic brittle failures of other blade steels. (Like when the Dutch Bushcraft Knives Channel on youtube tested the MKM Sak-a-like that has titanium scales and an M390 blade and it broke.) Where you can find some “hard use” type test videos of Saks that also baton and don’t fail that way.

That said in my younger years I had a 1 layer Sak with a phillips backtool and I completely destroyed it when the pin and liners all bent. Stronger pin, liners, scales would have allowed me to keep torquing until the SS failed and rounded off.

A lot of people have been swapping in Spyderco blades into their Mods, which come in different steels that you may prefer. In the mean time you could also just run the SAK as is and wait to see where it fails before making changes. If you poke around the “show me your sak mods” thread you will find some of those mods I mentioned.

Thank tou for the reply.
 I know that even as it is ,it will never fail because A) is quite strong  B) i can feel the limits of my tools and i adjust my handling. But it simply would feel nice to improve my climber.
 Plus my rangergrip 57 should be strong enough to use the hex bit hole . Now the factory allows only the 5 layers , 130mm models use the hex bit hole
 The soft steel may delay catastrophic brittle failures but on the other hand it may allow permamt shape disformations
 I feel that the most important factors are
 a) the rods. In my mind i suppose that steel screws should be better
B) The external liners. Perhaps it would be an improvement to replace the scales and external liners with a unified piece of steel of equal thiknes(liners and scales). No doubt it would be more expensive to built
 But there far more experienced people on this forum that know better

[tattoosteve99]

Have you checked the ranger grip to see if it has stainless pins? I do remember taking some models apart that had those type in it. As far as would replacing the brass pins make it stronger? Yes of course it would. But it would need to be the right type to prevent gauling
If you did decide to change to 1/8 pivots as suggested that’s a give and take. The 1/8 pivots will be stronger but you have to drill out the tools to make them fit thereby making the tool itself weaker. 

[Jim158]

Have you checked the ranger grip to see if it has stainless pins? I do remember taking some models apart that had those type in it. As far as would replacing the brass pins make it stronger? Yes of course it would. But it would need to be the right type to prevent gauling
If you did decide to change to 1/8 pivots as suggested that’s a give and take. The 1/8 pivots will be stronger but you have to drill out the tools to make them fit thereby making the tool itself weaker.

Hi
My rangergrip 57 has brass rods of 3mm diameter. I wish I could insert a photo. Actually the 130 mm knive feels very strong. I believe it's because of the liners configuration that can not use the hidden hex driver
 I totally agree with you that there s no point to drill out the tools if I want more general strength in my climber.
 So, I imagine that I should look for stainless steel 3mm rods. I don't know if they exist or if will be possible to work with them and secure in place
 Currently ,it appears , that my project is not possible with reasonable effort
 I don't want a mod just for better appearance.

[Vidar]

Stainless steel 3xx series 3mm rods are standard stuff in metric countries. So easy to get hold of anywhere but the US, Liberia and Myanmar..  A certain Ali Ex Press in China typically have metric sizes of most stuff. (On average about 3-4% of things ordered there seem to go boom in the night so there is that...)

That said I'm with tattoosteve99 on the potential gauling issue. As normal 3xx 4xx series stainless steel is quite a bit softer and weaker than many other steels. (Many of 4xx can be heat treated though). Of course many other steels rust.. (Duplex steel EN 1.4462 or 17-4 should be better, but they might indeed be hard to come by in the right size in small quantities).