Machining a TI-89 Out of Aluminum

TangoMargarine writes "Sometimes, expensive calculators hit the floor. It's happened to almost anyone with a graphing calculator from TI or HP. Sadly, they don't always bounce. After this happened to [Howard C.], an Industrial Engineering student from U. of Iowa, he decided to spend $50 on milling his own replacement case out of aluminum rather than trashing the device over a broken battery compartment."

Re:ok but

[Desert Raven]

Agreed, I went through a couple of TI calcs before buying an HP. I've never had an HP break. That's not to say I haven't dropped them. My poor HP 11C is now over 25 years old, and has been dropped too many times to count. It's still my favorite calculator. My 48G has likewise seen some rough handling, it is also still running fine.

TIs are decent from a functionality point of view, but they are unable to take any kind of rough handling.

My wife used TIs in college, and went through a couple of them as well.

cost

[donnyspi]

I can't begin to understand why these calculators, which have been around for many years and still have the same features and functions, cost the same as they did when I was in school about 15 years ago. http://xkcd.com/768/ [xkcd.com]

Awesome. How do I do that?

[vadim_t]

I'd like to do the same thing. So I'm hoping somebody could give me a few hints on it.

First, how did he manage to come up with a design for the new case matching exactly all of the buttons? Do you just take some calipers and start measuring? The curved layout of the buttons, and the shape of the buttons themselves look tricky. Also I imagine that accurate positioning of screw holes is critical.

And second, how does one get such a thing manufactured? Are there places available to normal people that would take an order for a single piece or a small run, and what file format would they require? Or a place where I could get access to the hardware and operate it myself?

I would be really appreciate some pointers about how to get started.

I'm working on an aluminum HP 11

[NixieBunny]

but it will use Nixie tubes for the display, just to make it interesting. It's fun to do the CAD design. Someone else will have to help me with the software, as I'm more of a hardware guy.

Re:ok but

[Chris Burke]

Yeah, and according to the comments he left, since he really needed a calculator he ended up buying a new one before finishing this project, so the aluminum TI-89 sits at home instead of traveling with him. So the lack of shock resistance in the new case is probably not a big issue anyway.

Re:cost

[soupforare]

They're test-legal and a de facto standard in schools. It's ridiculous but it's kept prices high as hell. The casio graphers are speedy, work well and are cheap. Unless you expect to be taking a placement test anytime soon, there's no reason to stick with TI.

Re:cost

[MightyYar]

The casio graphers are speedy, work well and are cheap.

I used Casios for years until I was converted into the RPN religion. Casio had a algebraic entry system that was ALMOST as fast and clear as RPN, and the calculators were much, much cheaper than the TI models.

Of course, now I've gone RPN and I'm spoiled - even have to seek out software RPN calculators for all my computers and devices :)