Do I really have to cut through the lock?

October 30, 2007 4:50 AM

Bicycle was locked outside (it's against the rules to bring it inside the apartment where I live). It rained, and the bicycle wasn't used for some time, and now the lock won't budge (it rusted, I think): key goes in, but doesn't turn. I tried WD-40 but it didn't work. Before I cut through the lock, are there any other solutions I could try?
posted by sailoreagle to Travel & Transportation (21 answers total)

Maybe you didn't wait long enough. Let it soak overnight in WD-40 (or Ballistol may be better) and then try giving the lock a few sharp raps (without hitting and breaking off the key).
posted by pracowity at 5:09 AM on October 30, 2007

A ball point pen?
posted by LakesideOrion at 5:10 AM on October 30, 2007

You may have to apply and re-apply WD-40 (I like Liquid Wrench too) - sometimes it takes several applications over a few days.

That said, if your lock is cheap then go ahead and hack through it. Attack it from the "barrel" side (near where the key goes in.) You can try cutting the loop part, but it'll take a while.

Also, shame on your building for not allowing you to bring your bike in or providing sheltered (secure) storage! My bikes sleep with me...
posted by wfrgms at 5:24 AM on October 30, 2007

What kind of lock? Oh, and use a LOT of WD--both in the cylinder and where the hasp goes in.

Other things to try: heat, as in from a blowtorch. Tapping with a hammer. Heat + tapping with a hammer. All these as you try to turn the key.
posted by TomMelee at 5:38 AM on October 30, 2007

OK, here's something interesting which I tried once with success when I had no WD40 and was in a bind: I poured generic coca-cola over the lock (if you can make the lock sit in cola, even better I guess) and waited a few hours. It worked like a charm! The lock was a bit sticky though, but it was worth it. Good luck!
posted by mateuslee at 5:42 AM on October 30, 2007

If WD-40 doesn't work, hit up your local auto parts store for a bottle of PB Blaster; it's made for stuff like this. Soak it a couple times then smack with a hammer.
posted by bizwank at 6:02 AM on October 30, 2007

Oh, I asked just this thing once. In the end, what worked for me was a lot of Liquid Wrench, hitting with mallet, and forcing with key. Eventually the rust loosened.
posted by thirteenkiller at 6:05 AM on October 30, 2007

On your next lock put a few drops of oil inside before you leave it outside for any length of time.
posted by JJ86 at 6:06 AM on October 30, 2007

I haven't tried it myself, but I've heard good things about Mouse Milk from aircraft mechanics. Looks pricey though.
posted by cardboard at 6:11 AM on October 30, 2007

Seconding Liquid Wrench and seconding a light bit of reasoning from a hammer.
posted by yerfatma at 6:27 AM on October 30, 2007

Yeah, make sure you give it a few good whacks with a hammer or other large heavy object. You gotta jar it enough so it un-siezes.
posted by lohmannn at 6:42 AM on October 30, 2007

Naval Jelly is fantastic for this sort of thing.
posted by iconomy at 6:46 AM on October 30, 2007

If the lock is rusted shut now, even if you do get it open without destroying it, it will seize up when it gets wet again. Just use a cordless drill to bore out the barrel, and then buy a new padlock designed to withstand the wet.
posted by roofus at 7:07 AM on October 30, 2007

I've found graphite powder to be much more effective than WD40
posted by goshling at 7:25 AM on October 30, 2007

Assuming it's a U-lock, even the best models have pretty chintzy key/lock mechanisms. Hammers and mallets and trying to otherwise force the lock open will probably just break it. My boyfriend's U-lock key broke off inside the lock not long ago, fortunately while we were outside a hardware store. It took an amusing number of pretty hefty tools, weilded by the hardware store employees on our behalf, to finally break through it.

An angle grinder finally worked. Good luck!
posted by hollisimo at 7:54 AM on October 30, 2007

Seconding PB Blaster from an auto parts store; it's what's usually recommended for the same sort of thing on a car. May require repeated applications (spray, try, spray, wait, try, spray, wait, try, open).
posted by RikiTikiTavi at 8:55 AM on October 30, 2007

One note mentione by TomMelee, not only should you spray the keyhole, but spray where the other parts come together. Those could be rusted together as well, preventing the key from moving.
posted by advicepig at 9:35 AM on October 30, 2007

My vote: Much soaking (either with WD40 or PB blaster or the like) and heat. Rusted metal expands as it corrodes and has jammed up. It will also knit into every single surface imperfection creating a more complete lock than just a smooth thing in a smooth hole (no smut intended).

Heating and allowing to cool causes the two parts to move relative to each other, and also makes the hole bigger. Thus there will be less friction/interference. Soak it, heat it, let it cool, repeat. As soon as you get any movement of the key, soak heat and repeat with wiggling. Rust is brittle and will not be able to cope with too much constant small movements (from your wiggling and the heat) and will eventually give in - especially after so short a time in teh rain.

Then throw the lock away and get a better one. You'll only get it open (hopefully), not fix it.
posted by Brockles at 9:46 AM on October 30, 2007

2 nd. goshling's use of powdered graphite. When, and if, you free it sluice it through with dismantling fluid to wash away sticky oil residues, blast or two of compressed air, let it dry out and apply powdered graphite. Oil is no good for locks.
posted by Dr.Pill at 9:51 AM on October 30, 2007

PB Penetrating Catalyst has always been my more-successful WD-40 equivalent of choice. Good luck!
posted by thejoshu at 10:58 AM on October 30, 2007

If you've got room to work on it, I'd suggest using a car jack to pry the thing apart - A lot quicker than hacksawing it.
Not BikeThief-iest
posted by Orb2069 at 8:26 PM on October 30, 2007