Problem making a lockback

[ErikB]

Hi All,

I am experiencing some difficulties in making a lockback (I think that's what they're called). Here's an image of the kit: http://www.prixusine.fr/images/Uplo..._poche_Aurillac_(11cm_fer)_003_200306_000.jpg

Here's the site: http://www.prixusine.fr/PrixUsine/FicheProduit.aspx?ProdId=1864

Anyway, the problem I am having is that the sides seem to open up away from each other when I open and close the blade a few times. My theory is that there is some sort of an angle between the spring and blade that pushes the spring to one side and the blade to the other. I cannot tell, though. I don't see anything but that is how the pieces are behaving.

I have only test-fitted, perhaps this will become a non-issue after I hammer the pins into the bolsters and blade. But it seems to me that if there is a problem now then banging on that pin to thicken it and tighten the sides together is only a band-aid over a real problem.

Any ideas?

Any photos of spring/tang interfaces and some of the problems people experience with them? And how to solve it?

Thanks heaps in advance, folks.

-E

 

[MSCantrell]

Sounds like your pivot hole in the blade isn't quite exactly 90 degrees

 

[ErikB]

That's what I am afraid of.

Any way to fix that?

Would it probably making the hole bigger, wouldn't it?

 

[ErikB]

Alright, I think I figured it out.

The spring has a slight bend in in (laterally) so it looks a little like the letter "C".

It is also a bit wider than the tang.

So, I sanded the spring on its sides until it was straighter and narrower. Now, with the pins in and (what's the word?) hammered with the round hammer until the ends mushroomed, the action of the knife is a lot better. I think the problem is solved.