Been lurking, need a bit of help... Broken Picks

[dragonriot]

Hi all, I started being interested in locks about 5 years ago, and worked as an apprentice for a while until I couldn't stand him not paying me anymore... (He was actually training me to take over the business, but I needed a job now, not in 6 months.) Anyway, I just made my first set of picks this morning, consisting of a long and short lift pick, a long rake, a snake rake, and a tension wrench. The picks were made from the cheapest hacksaw blades I could find, which ended up being $3.00 for a pack of 5. The don't snap nearly as easily as I would have expected, but they do break fairly clean. I cut them down to blanks with a dremel grinding bit, and finished them with a dremel cut-off wheel. I have a "remote" dremel, so I have the motor part hanging from my basement pipes, and the remote is clamped into one of my bench vises... I made sure to continually keep the metal cool while grinding, and I thought I had done a great job when all was said and done. I took my work upstairs to try out on the front door.

I put in the tension wrench at the bottom of the key-way, and started with the long lift pick... it was too big of a curve, and while I could get to each pin, it just wasn't working right. I moved on to the snake (W) rake and thought I was being quite gentle, but as I pulled out the rake after a few jiggles and strokes, I found that it had broken inside the lock. After completely removing the door knob from the door and using a magnet to pull the broken piece out of the knob, I reinstalled it and tried with the long rake. After a few strokes, I saw a crack just before the first rake point, and slowly pulled the pick out of the key-way. It broke off in the lock again, but I had enough metal to grab onto and remove it without taking the knob apart again.

I don't understand why my picks broke though... I followed the instructions found here and in the pick making video by Pyro1234321. I don't believe there were any stress fractures in the steel before I started picking. I used very light tension on the tension wrench, but there was enough tension on it to somewhat twist the wrench at some point, likely while I was trying to get the broken piece out of the cylinder.

I just printed off a bunch of templates, so when I get home tonight, I'm going to try making some more picks, but this time I'll try a file instead of the dremel. It may take me longer, but at least it won't be brittle from the heat of a 10,000RPM grinder disk.

[FiapFiak]

could u post the pictures of the broken picks?

as well, it could be
a) bad hacksaw blades (most likely)
b) maybe your technique, (are you putting any pressure on the side? hacksaws cant take side pressure)
c) your pick design

but since u can see the cracks before...
i'm really betting on bad hacksaw blades.

And you're going to use a file? on hacksaw blades?
do you know how much of a workout that is?

[dragonriot]

hehe... I can stand to lose a few pounds and build a bit of muscle... I've become a bit flabby since I got out of the Marines. =)

Anyway... good point about filing hacksaw blades... they eat cutoff wheels like candy... suppose its a good thing I have about 50 wheels... I'll probably buy some plumbing snake from the local hardware store... in fact, I think I'm going to head over there now!! =)

[dragonriot]

Well, the hardware store didn't have any flat stock except "starter spring" for lawnmowers, which I suppose would work... but it wasn't wide enough in my opinion. I ended up getting copies of a few of my keys made while I was there, and I'm going to make a bump key out of my new front door key, just for testing purposes. While I was out, I stopped at the auto parts store for a headlight for my wife's car, and found a needle file set in the "Bargain Bin" for $4.99... not bad... bought it.

So, I might head over to Menard's or Home Depot tonight to see if I can find some flat plumbing snake or wider spring steel... Any other suggestions on where to buy stock would be wonderful...

Oh yeah, the saw blades I bought were "DoItBest Carbon" blades, 24TPI. They seem to flex way too much when I'm breaking them, but then after manufacture, they are brittle as hell... so since I just watched the tempering video (thanks unbreakable) I'll try tempering a new rake tonight...

[arris]

one thing the guy i work with allways tells me

"you cant have hardness without britlleness"

rember that hacksaw blades are very hard to cut thru other metals..

[FiapFiak]

Really, try to post a few pictures of your broken picks here, it can help us help you way better.
if we see it, we can maybe tell you more accurately what the problem is.

You seem to be going to hardware shops... try feeler gauges? they work well