So... I wanna try bumping :\

[Solomon]

What can I say, I'm curious. I'll probably get bored of it once I get the hang of it, but I have an itch right now and I wanna give it a go.

Some say there's no skill involved, others say there's a bit of a knack to it. Either way, I wanna at least try for myself. I'm gonna get an old key copied and make a bump key out of that... I don't wanna use the key I have because if I mess it up, it means I won't be able to get another copy to try again. Apparently it's a very precise thing, however I saw a video where Hans Fey was demonstrating the use of bump keys, and he recalled how he had seen some awfully made keys which worked just fine. I wanna do the best job I can though, and for that, I need you fine gentlemen.

Here's my idea. I'll measure the valleys and draw a line from the centre of each one, at 90 degrees to the bottom of the key, as follows... this will ensure I am filing in a straight line and the valleys will be even (hopefully, lol):



From here I will file down using a square file, keeping each valley with a 45 degree angle each side - this is kinda to scale, the file is roughly that size:



Here's a pic of the file in one of the existing valleys, want you guys to know as much as possible to make sure it's suitable



My only real question at this point is, how far down do I file? As far as I know, it's down to this point... please correct me if I'm wrong:



The finished product should look like something like this:



As far as I know, you're supposed to remove 0.5 to 1.0mm from the end of the key aswell as some of the shoulder. What are your thoughts on this? I'll try it out before I make these modifications anyway, but from what I hear, it works better that way. Thanks for all the help, guys!

[datagram]

You will file down tot he lowest bitting depth, which varies from lock to lock. Most keys stop their bitting at the first warding, or just below it. Your picture of the bump key looks much too low, I'd guess it would instead stop cuts right around where that lowest cut is on the normal key. You can look up the key specs for the lock and find out what the actual lowest bitting depth is to be precise.

dg

[barbarian]

Looks way too low. I bet that one won't even touch the pins.

The deepest cut before you started was probably deep enough.

[Solomon]

Alright, so it doesn't look *too* bad... not for my first try, anyway. It doesn't work, although I can hear a few pins dropping back into the plug when I stop applying tension so it's definately doing something in there. I think the valleys just need to be a bit more uniform, ie. all the same depth as the first one. There is also a chance that I took too much of the shoulder off, I was taking it away bit by bit during testing.



Thoughts?

[sparkster]

you will get a few pins setting in the lock, but the spacing of your key is way out, they have not got to be absolutely perfect but you need to try agn with another key, removing some metal from the shoulder is just a simple process of drawing the file across it a couple of times, using the minimum movement method is made easier by this, but you can pull the key back one click and bump using that method, i have bump keys around that have had nothing taken from the shoulder and work fine, get your cuts equally spaced first then work from there.

[Solomon]

Yeah, looking at it now I can kinda see how bad the spacing is... I think I'm gonna just fold and just buy a set, that way I have something to actually look at properly if I decide to make my own again. I was never the best at making things, but if I do decide to make anything remotely technical I really need to see it from every side so I know exactly what I'm doing, otherwise I get muddled up and it ends up looking like... well, you can see.

[sparkster]

Dont give up on trying to make your own tools, its part of the fun and it boosts your confidence when you make something by hand that actually works, keep at it.

[ridinplugspinnaz]

Might I suggest a different approach? On occasion, I've cut keys with a hand file with the desire to make them look aesthetically more like a code-cut key than a hand-filed one. The way I do this is to take the short side of a flat file and file directly down to the desired depth, then take the longer side of the file at an angle to the cut I've made, so as to manually recreate the ramps that a key punch would normally make.

It does take some practice to do effectively (the smaller the flat file, the better off you likely are), but the results are pretty pleasing. Given that a well-made bump key is usually just a key that's code-cut to all 9s with modifications to the tip / shoulder as needed, you might do well to try to replicate the kind of cut that a key punch makes as closely as possible. If you do it right, you'll have a bunch of nice little pyramids between the pin positions that act as perfect bumping surfaces.

[adrenalynn]

Not bad for a first try!

You don't need to take so much off the shoulder. If you're not trying for the zero movement method (and if you're just starting, you probably ought to consider not doing so), then you really don't need to take anything off the shoulder. Just pulling back one click before the rap avoids needing to file the shoulder down. But that does look (in addition to spacing and depth) like you've taken too much off, so it will never line up [even more] and may damage the mechanism, depending upon the lock design.

[christmas8371]

hi, i'm wanting to make my own bump keys too and found this video tutorial which seems to be very helpfull. will have a go at making my set sometime next week and will post results. http://www.tvlesson.com/video/26915_how ... p-key.html