How to fix a Lock back that doesn't close?

[LDF Knives]

I have a knife that won't close on my Lock back, is that a defect? I've had this knife for 30+ years but this is a Frost (that might be why) so what's the trick if any Thanks

[cudgee]

I have a knife that won't close on my Lock back, is that a defect? I've had this knife for 30+ years but this is a Frost (that might be why) so what's the trick if any Thanks

Is it locked in the open position, or closes but not completely?

[LDF Knives]

I have a knife that won't close on my Lock back, is that a defect? I've had this knife for 30+ years but this is a Frost (that might be why) so what's the trick if any Thanks

Is it locked in the open position, or closes but not completely?

It is locked in the open Position, cannot close it

[Jeffinn]

The standard lock back knife is fairly simple (at least the ones I’ve worked on so far have been). The mechanism on your knife should look something like this:
[attachment=0]E739A137-699D-42AB-AB23-C7D72F94F436.jpeg[/attachment
This is a Ka-bar mechanism but the Schrades I’ve worked on are similar. I haven’t had a Frost apart but I’d assume they’re similar as well.
Jeff

[ea42]

Can you depress the lock bar? if not try giving the portion that you press a smack on the edge of a table, or alternately lay the knife down with the spine facing up place some type of punch or dowel against the lockbar, then hit the punch with a hammer or mallet. You don't want to smash it, put don't go too light either. Just make sure that only the bolster or liners are in contact with the table and not the blade edge, bone or something brittle. You could even hold it in you hand an hit the bar with a mallet. Seems like something might have frozen or bound up. There's also a chance that something got under the lockbar and is jammed between it and the butt piece. Try scraping under there with a toothpick.

Eric