cock/tumbler fit question

[Sean]

So I'm working on a lock that needed a bit of tweaking.  I talked with the company about some stripped screws it came with and elected to get the parts sent out to me instead of waiting a 2-3 weeks to have the shop look at it.  They did that in a timely manner, but once I got a little further in a couple other things came up.  As a result I have a couple of questions for y'all who have more experience with locks than me.

1) When the builder fit the cock on the tumbler they had to tighten the hole in the cock a bit with a punch.  When they did that they drove a tiny bit of metal out into the hole such that it lays over the top of the tumbler shaft.  That means the cock is not square on the tumbler and there is a tiny bit of play between the cock, tumbler and plate.  Before I go filing on this thing, should there be?  Should I just file that off so I can seat the cock a bit lower on the tumbler shaft. 

2) Also, how much play is too much between the tumbler shaft and plate?  I can wiggle the tumbler shaft a tiny bit in the lock plate.  Should I be concerned about that in terms of wear.  If so should I try tightening it a bit with a punch or just harden the plate?

Am I being too anal here?  I realize these questions may be difficult to answer without having the lock in hand, but I will be grateful for any responses.

Sean

[J.D.]

I'm a novice at lock work, but since no one has replied, I'll throw in my tuppence.

IMHO, ideally,there really shouldn't be any play between either the tumbler and the plate, or between the cock and tumbler. However, a little doesn't really hurt all that much.

One fix for the tumbler hole, in the cock, is to file off that extruded metal and using a large ball bearing placed on the square hole in the cock, smack it good to evenly bump metal from all sides to reduce the size of the square. Then file, very carefully, until the cock presses onto the tumbler, with some small pressure.

Both sides of the cock may need this treatment to get it to fit snugly.

As to the play between the tumbler and axle hole in the plate? To my knowledge, there isn't a whole lot that can be done about that, other than welding the hole in the plate and redrilling, or installing a bushing.  Installing a bushing will obviously require machining, but is no big deal if you have the tooling at your disposal.

If the tolerance isn't too bad, say not over .010, I would just harden the plate and live with it, unless you have the equipment to do the necessary work.

IMHO, considering the cost of a new lock, I would send it back and buy a Chambers.
I have only used a coupla Chambers locks, but they have only needed minor tweeking to get 'em as right as I know how.

God Bless,
J.D.

[Acer Saccharum]

The fit of the cock on the tumbler shaft should be a tight fit. No play, no wiggle. This is in the ideal world.
If you have room between the cock and the lockplate, you may be able to fit the cock further onto the tumbler shaft. That's what I'd look into first. You maybe able to braze the hole to add material for fitting; or weld it up and re-file. I think you could also heat the whole end of the cock up, and hit it with a hammer to close the hole up. This will make the cock thinner, though, which you may or may not be able to get away with.

It's pretty nigh impossible to tighten a tumbler hole in a lockplate without bushing it. if it's only a little play, I'd leave it.

Acer

[Sean]

Thanks guys.  I will say this is not a Chambers lock.  I've never had a problem with those that wasn't my own !@*%&@ fault.  In fact, I talked to Barbie recently and told her that it was apparent that the guys who assembled their locks loved their jobs and took pride in their work.   Anyway, after I got this thing reassembled I was less unhappy with the tumble to plate fit.  At least under spring tension it doesn't seem so much.     I'll probably cook the lock plate in bone meal or charcoal to harden it with all of the advice Jerry and Acer have provided here in the past.

Sean