Jacques Mattheij

Technology, Coding and Business

The belt sander and the battle for privacy. A body hack.

My government has gone nuts. It’s tough to admit it, but they’ve enacted laws here that would have made the former Stasi, the VoPo’s, KGB, and other secret services in the former SovBloc countries drool with envy.

And if those countries had adopted laws such as these we’d have condemned them roundly for the privacy violations against their citizens, and we would have pitied those citizens for having to live under such regimes.

Since a few years we now have to file 4 fingerprints when applying for a passport or an identity card, as per the EU directive on ‘biometric passports’.

Supposedly, this is to guard us against criminals falsifying passports. One slight problem with this theory is that nobody ever checks those fingerprints. But they do want them.

My government goes one step further (or maybe they’re just a bit more open) in that they not only want your prints, they also file them, in case you might become a criminal at some later point in your life. The idea here is that, since you’ve got nothing to hide, you should not have anything to fear.

Tell that to Brandon Mayfield, whose only crime was that he converted to Islam, and whose print turned up in the aftermath of the Madrid bombings:



http://en.wikipedia.org/wiki/Fingerprint (section ‘criticism’).

Two people here have started lawsuits against the government, one of them died while waiting for a ruling (for the conspiracy nuts: no, he died of natural causes), the other is still waiting.

Having nothing to hide is not good enough. Even if you have nothing to hide you can easily become a suspect in a crime committed many years later with which you have absolutely nothing to do.

To avoid getting into situations like this, and because I do not actually trust my government to be able to store my fingerprints without losing them to parties unknown (or having them copied by compromising the data store), I resolved to do without a passport / identity card.

Technically that’s against the law here and lots of people have been fined over the years for being unable to identify themselves, but I thought that was the lesser evil.

Unfortunately, my business depends to some extent on my ability to travel, and I simply do not like to be without a passport, so I decided to hack the problem.

Everybody has fingerprints, right?

So what about someone that lost both hands?


What about old people?


What about people with a genetic mutation that causes them to have no fingerprints?


People using certain drugs:


And on and on.

It is estimated that 1 in 50 people do not have prints or prints clear enough to be registered by the fingerprint readers currently in use.

That’s a lot of people, and I decided to artificially increase that number a bit. I’m not sure if the following is legal, but frankly, I do not care. I’ve got nothing to hide, but I refuse to cooperate with the current security craze fueled by fear of terrorism and criminals. The country where I live has one of the highest incidences of death-by-the-grim-reaper-of-old-age, and I think that we have far more important things to worry about than either terror or crime. An out of control government, for instance, that seems to think nothing of violating the privacy of its citizens.

Enter the belt sander.

After thinking about the problem for a while, I decided on trying the most simple and direct way that I could think of to simply remove my fingerprints. The belt sander is a pretty simple tool, I have one in my toolchest and it did the job quickly and relatively painlessly. The way to do it is very simple (of course I’m not responsible if you get jailed, tortured or executed by doing this, or if the authorities refuse you a passport):

  • set the belt sander down upside down with the moving belt exposed;

  • have a glass or small bowl of water handy;

  • sand your prints off one finger at the time pressing down very lightly on the fingertip;

  • whenever your finger feels warm or hot, immediately dunk it in the water, that way you avoid burning your finger;

  • check your prints using a mirror and some cinnamon or other fine powder. If it works, you’ll see just a smudge instead of a clear print. Try comparing with a finger that you have not done yet to see the difference;

  • make sure you spend about the same amount of time on all your fingers;

After about 30 minutes of work you should no longer have prints. Touching stuff will feel very strange at first, specially smooth surfaces. Since the prints allow the oils that coat your fingers an escape when you press down on them (the whole reason we have fingerprints), you’ll notice when your fingers are smooth that when you try, for instance, to lift a glass, that you have noticeably less grip.

To see how well it worked, I applied for a passport. Several times the scanner completely refused the print, one finger (left thumb) came up clear and three others were clear enough to be registered as ‘prints’ but they looked pretty bad to me. So, partial success in my case, if I had known how good the scanner is I would have spent some more time on sanding them off, the method does work, I just did a sub-optimal job of checking the result, it seemed good enough at the time though, so when you think you’re done, add another 10 to 20 minutes or so to make sure you got it right.