Stretching a titanium leaf spring .

Frank Niro

KNIFE MAKER
There are times when you cut that liner lock spring just a hair short. For some it means having to make the liner over again. For me I lengthen the spring. What I do is use a triangular piece of hardened metal about 1/8" on each side. I place the liner so the side that goes next to the scale is up, place one of the edges of that "tool" across the leaf spring say 1/4" from the locking end and give it a tap with a hammer. That was a tap. not a rapp. Did you see a line right across ? If not your liner is now positioned a bit up or down from the original position. Another tap with the tool leaning on the shasllow side of the V groove and you may have it done. Try an assemly with the blade and washers, pivot, spacer and screws. If you need a bit more move just a bit behind the first adjustment position and tap again. Once you have a proper fit, taper that same side of the lock with less thickness towards the front, to remove the marks. The tapered tang will now allow more room to pass the detent ball when moved over to close the folder. No, I haven't found that this weakens the spring to make it bendable it you try closing the blade without disengaging this locking spring. I hope this helps someone, some where. My next posting will be on an aid to smoothing up blade movement. Frank
 
Frank, is it possible to get some pictures of the process and tools?

I didn't see this moved, so I asked the question here.
 
Ron.
I appologize again to everyone but I don't do pictures. I've been holding off on posting a neat grinding jig but Tracy, Boss Dog is going to help me.
I'll try to help with just words. Here is an example with a piece of scrap or stainless, make a strip a couple of inches long and about 1/4" wide. Measure the length . Place it on a metal base. Now if you have a cold chisel place that on the strip and hit the cold chisel but not too hard with a hammer. If necessary flatten the strip and remeasure. Well you won't have to since you know it will be longer. Now in the case of the locking leaf tha's just a bit short do the same thing but by laying a small triagular hardened metal strip across the leaf and hitting it on the op flat. Don't try to make the necessary adjustment all in one spot, and do practice with the triangular piece on a piece of scrap.The smaller triangle will cause you to take more care when doing this adjustment. I hope this helps . It can be a very helpful way to go and if taper your leaf springs it is just a bit more to do. Frank
 
Frank, I am sorry, but I must be dense. Attached is a sketch I did. Is the tool like shape A or B? Do you hit the Ti with the area circled in red? For shape A is it red area 1 or 2?
 

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Frank, if you can send me pictures, I'll get them posted.
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Frank heres another way to do it.If you cut a half-round relief at the rear of the lock you can use a piece of pipe,tubing,drill bit,etc, the same size as the relief to lengthen the lock without leaving any kind of marks.
 
"A" is the tool I use. The makes should be removed when the leaf is tapered. Hey, now I'm the dense one. Mcahon please explain more.
Boss Dog, I hope to get my "act" together and some help from my wife by the first part of the week. Thanks again Tracy.Frank
 
When I've made liner-locks,I often use a ball mill or 1/2" wheel to cut a recess at the rear of the lock spring near the rear end of the handle.I do this if the Ti is .090 or over as I find too thick of a spring can lock up too tight sometimes.So if the lock has too much play,I can use a round object placed in the recess and hit with a hammer to lengthen the lock spring without leaving any noticeable marks.If thats still not clear,let me know and I'll get you a pic.
 
mcahon, where here it is, even though I can't do the picture thing I would appreciate one now, and thanks much for asking if I would. Frank.
 
Frank the technique that I use is to mount a cross peen hammer in a vise and place the titanium on that edge and tap the titanium to leave a neat little line in it. This stretches the lockbar a thou or two each time I repeat the proceedure.

George
 
Does a cross peen hammer have a rectangular head, George? If it is the meathod and results would be the same. Thanks. Frank
 
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