3D printing - the future of lock manufacturing?

[ninjalectual]

I was trying to explain to my dad how picking works. He comes from a field where he uses precision manufacturing techniques, and mechanical tolerances are exceedingly small. He flat out didn't believe me when I explained that the pins on a commercial lock aren't all in a straight line until I demonstrated it.

But say I were to design a lock in CAD and print it on a printer with mechanical tolerances measured in microns (printers like this can be had for under $3,000 now). Obviously it's still pickable, as the pins need spaces in order to move up and down, but if the pins were made to the same tight tolerances, is there a level where there essentially isn't a discrete binding order? Assuming you can't (or don't want to) rake or bump it, how would you go about picking this lock?

Is there something I'm missing? I can't believe this kind of precision manufacturing is that far away, any large corporation should have this ability now, for not much more than consumer locks cost to manufacture already. Is there a reason this wouldn't be objectively better?

[MacGyver101]

Such a lock might not have a clear binding order when it first comes off the line. However, you need to make the pins slightly undersize to the pin chambers (otherwise you run the risk of failure as dirt builds up inside) and the elements at the front of the lock are subject to more wear than the ones at the back. As a result, I think you'd find that the tolerances will start to pretty quickly degrade due to usage.

[TNEtechie]

All the people I work with are just thrilled about the "future" of 3D printing, and I am constantly pulling them back down to earth.

3D printing is a lot like machining, except it is a deposition process instead of a removal operation. The tolerances in machining processes are to accomodate the limitations of precision and repeatability in machine motion and numerous other variables. A 3D printer is a mechanical device subject to the same variables... i.e. thermal expansion, and raw material and tooling, which are themselves manufactured products with tolerances...

The real promise of 3D printing is fast and economical production of protype or low-volume parts. Moving from a CAD drawing through CAM software to machine motion is incredibly fast and easy.

Measuring in microns is one thing. Manufacturing parts that are consistently within a few microns of ideal dimensions is another thing altogether. A $3,000 printer will not repeat motion or product with this level of precision. Even the best 3D printers today and in the foreseeable future will not repeat motion or product with this level of precision.

Though you may soon be able to print any mechanical lock that you can visualize, it will be just as pickable as locks currently machined or formed by other processes.

[floridaguy]

I think that also because 3D printing is mostly just in plastic, the tolerances are way lower than what an actual metal lock would be. Plus, plastic is softer and wears down faster so the tolerances would fall that much quicker. Cool idea though, printing a lock! I've tried is and it doesn't work as well as you would think. There more friction with plastic than metal and so it locks up really easy. Opens smoother by picking than by key! lol

[TNEtechie]

[quote="floridaguy"]I think that also because 3D printing is mostly just in plastic...

No, it's not just plastic anymore... In selective laser sintering, lasers are used to fuse various powders into solid form, including steel and titanium. Part geometries are not limited by the constraints of tool geometry. In other words, you can easily design and produce a lock mechanism that would be impossible to machine or cast.

[quote="floridaguy"] the tolerances are way lower than what an actual metal lock would be.

You have your high/low thinking backwards. Don't feel bad. This is common outside of manufacturing.

Think of tolerance as the amount of imperfection or error you can tolerate. If we could produce a part with all dimensions exactly per the print, we would not need any tolerance. However, there are no perfect parts, and the closer you need to stay to spec, the more it's going to cost you.

So, a "precision" part is LOW tolerance, and it's expensive. If your manufacturing cost has to be low, you will want your tolerance to be HIGH. This is one reason cheap locks are easier to defeat. High tolerance parts often need more clearance in the design to accomodate the range of possible fits, and this makes a "sloppy" mechanism.

All that said, 3D printing is really just another manufacturing process subject to all the same physics and economics that make today's locks so much fun.

[TNEtechie]

3D printing promises more immediate and useful implications to lockpicking:

Restricted keyway? No problem, print a blank. Even better, print a working key from a drawing made from a photograph of a key.

Want a special pick made of an exotic material? Print it. Want to modify an angle or change the handle? Edit the drawing and print.

Yes, this is scifi... (My old Nextel flip phone was initially conceived as Captain Kirk's communicator.)

[overWeight]

New here, so please forgive me. Wouldn't 3D printing be useful for keys or at least temporary (plastic) keys? Seems like impressioning would be easier and quicker with a key printed in ABS plastic. Not sure if anyone does this, or if its already popular.

[KPick]

New here, so please forgive me. Wouldn't 3D printing be useful for keys or at least temporary (plastic) keys? Seems like impressioning would be easier and quicker with a key printed in ABS plastic. Not sure if anyone does this, or if its already popular.

I actually thought about this idea before. How would this workout? Has anyone tried this?

[Ehr160]

Wouldn't a plastic lock really lower exterior security. I mean A blowtorch would have it open/destroyed in seconds.

[KPick]

Yeah lol. Just imagine getting home and you see your lock destroyed. I would be happy to see all my stuff gone after it's been stolen. Thank god the plastic lock held them up for about a minute. Ooops it's been melted I see. It's okay. I only paid 2 dollars for it. I'll get another haha. :p

[bembel]

TNEtechie already mentioned that there are also metal printers, not only plastic printers. But they're terrible expensive, slow and I'm not sure if the metal quality is the same. I also don't know how 3D printing can be more precise than a good CNC production line (but I'm not an expert here).
Either way, there will be tolerances.

[voronoip]

It's popular to use the plastic 3d printed model to create a plaster negative, which is then used to cast the metal. I don't know how effective it would be for making locks though, but it sounds like a wonderful way to prototype some wacky lock ideas.