Wednesday, June 3, 2009

Shiny New Toy

I forgot how enjoyable it is to come to work when no immediate deadlines are demanding attention. I really do love what I do - I like research, I like my labmates, I love building stuff.

But you know what I like best of all?

Shiny new toys.

My lab just got a new piece of equipment - a micromilling machine. This is a fantastic piece of precision equipment that can make cool stuff with very tiny features out of metal or plastic. It's functionally just like a regular milling machine, but it looks different. And it comes with a special high-speed spindle, extra stiff bearings and frame to minimize errors, and it uses little tiny drill bits.

Seriously, how cute are these?



I know how to use all sorts of machining equipment, but this is my first time learning something that has to be this precise. I need to cut metal molds that have features about the width of a human hair, so it takes some special coding and procedures. I've been trained on this machine, but that was four weeks ago, and I can barely remember my name from one week to the next.

So another labmate and I tackled the project of getting something machined this afternoon. We decided to start in plastic, which is easy to machine, and to use a 1/8" end mill, which is the largest size end mill we have for this one (which is tiny, for a regular milling machine).

We were happy when we completed all the setup without a hitch, and thrilled when our test piece actually was running.

Then I noticed the piece we were making was ugly.

Really ugly.

We let the program finish, and when we pulled it out we discovered why the part was so ugly. Instead of the end mill looking pretty like this:



The end mill looked like this:



Apparently we chose a feed rate that was a little too fast, and it melted the plastic chips onto the drill bit as it went. Whoops! Big ol gob of gook on the end means the end mill doesn't cut so well...

Have to try that one again tomorrow...

1 comment:

  1. This remind me of the machining courses I took at high school; I never got to machine plastic but I worked mostly with steel, aluminum and stainless steel (my brother provided me with big amount of culinary grade stainless); only problem that I had was with the stainless, it was very ductile and so, the entire mill vibrated through the floor and shook everything around (the piece of stainless were on average 4x4x8 inches).

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