Computer I/O shield Experiment, Take 2

I just wasn’t happy with the experiment, so I tweaked the file a bit and milled a second one. This is on the back of the computer and nobody will even give it a second thought, but it was annoying me nonetheless.

Milling

Done.

Comparison, old one on top.

In place. I probably could have moved the USB cutouts over another .01” but it’s much better now.

Happy kitchen PC. Running Xubuntu.

Computer I/O shield Experiment

I recently came across a large pile of new in the box computer parts at a garage sale ("at pennies on the dollar", said I to my suffering wife). I ended up with a processor (Core 2 Duo, 2.2Ghz), 120 GB hard drive, 4 GB DDR2 ram, Antec case w/ power supply, all of which were hypnotically commanding me to make a complete PC.
So I looked around online for a cheap Socket 775 motherboard and bought one from Geeks.com. It was refurbished and I didn’t notice that the description stated “Cables, I/O shield and Driver discs are not included.”. The I/O shield serves several functions, blocking off excess airflow, grounding the I/O ports and most importantly, shielding RF noise (these are all the fodder for much debate on computer forums). This last become apparent as a buzz on the audio line when I hooked the PC up to the kitchen TV.
Small detour: Did you know that most flat panel LCD and plasma displays usually have standard PC VGA inputs? Yup, they are all waiting expectantly to be hooked up to a computer. You can watch online content (Youtube, Hulu, Netflix, etc) as well as streaming audio from your network or the internet. In most cases all you need at a VGA cable and a 1/8” audio cable. (leaving aside the subject of HDMI which has vexed me of late on our living room TV).
So I figured I would attempt to make an I/O shield. I have come across this problem (missing I/O shield) several times before so I figured that what I learned from the experience would probably pay off later on. I did learn several things, most importantly to not buy motherboards without the I/O shield. (Mom, I/O means “input / output”.)
   
I took a picture of the back of the case. That curve to the motherboard is not a camera artifact, the motherboard is warped. What did I expect for $20?

I cropped and tried to get the sides parallel in Paint.net

I brought the picture into Rhino and scaled it to suit the ATX standard (6.25” x 1.75” +/- .008”) for the I/O shield hole. Then I drew some boxes around the various components.

I generated the toolpaths in MadCam (an excellent CAM plugin for Rhino, which was generously donated to yours truly by the fine folks at MadCam.

Beginning the milling operations on the Taig CNC mill.

Almost done.

Attached to “sprues”.

Cut free and cleaned up. I spent some time deburring.

It didn’t quite fit in spite of being within the specifications. So I filed the edges a bit and got it into place. So my second lesson learned is to reduce the edge dimension by .004” on all sides. Still within specifications but with some wiggle room.

Not quite what I was expecting…Seems that I miscalculated or otherwise managed to locate the cutouts slightly to the right of where they should have been. This is with the motherboard shifted left as far as possible. I said it was an experiment…My third lesson is to take some other reference measurements, which I thought I could avoid by working from the picture.

But the USB cable fits in the connector so all is good. I may remove it and file the openings slightly larger on the left side, or I may just leave it. Maybe I’ll make a new one later.

So there it is. Hooked it back up in the kitchen and there is now an absence of buzz on the audio output.
UPDATE: I decided to try again with better results, link to post.

To LA And Back, Part 3

On our way back home.

Victoria drove us to the train station. LA traffic is wonderful.

Outside Union Station.

Henry had a Wetzel’s pretzel for lunch. He enjoyed it.

Coming back along the coast at high tide.

It was  a bit gloomy but beautiful.

Some lunch.

Another stop. The couple in the foreground live in Oakland and were coming back from LA. He works at a large US Mail distribution center in Oakland.

The guy walking towards me is on his way up to UBC to study for a masters in Forensic Psychology. His main field of research is surfer and skater culture.

The “horseshoe” curve between San Luis Obispo and Paso Robles.

That’s highway 101. The train is pretty high up on the hill.

Back in Oregon, so green. The train was late getting into Klamath Falls so we were able to enjoy views of Mt. Shasta. I had a long conversation with a sheep farmer from New Zealand as we wended our way through the cascades.

Goodbye parlor car. That’s Angelina, our porter on the left.

To LA And Back, Part 2

Morning in LA, or Alta Dena.

Peter, Charlotte and Shadrach relaxing on the couch.

Their back yard has a nice view of the mountains.

Harry, Max & Henry playing Wii.

Peter shoveling out the chicken coop.

We went to their swim club.

That guy on the right is an actor I recognize but I can’t place his name or what he’s been in. Which probably explains why he belongs to a relatively inexpensive swim club rather than some posh country club. Harry is enjoying a shaved ice.
Edit: Peter found out who he is, it's John Michael Higgins. He was Mentok the Mind Taker in Harvey Birdman Attorney at Law! Not that I recognized him from that role.

The next day we went to the California Science Center.

The kids enjoying a zoetrope.

Some thermal imaging.

Charlotte in a hurricane chamber.

Felice learning to fly.

Hanging out by the fountain.

Peter is really excited.

Everyone shoehorned into the Odyssey for the trip down to Legoland. I will stress at this point that the idea of visiting a theme park was none of my doing.

Such a happy guy.

Ewok and my nostrils.

I’m happy I can deny piggyback rides.

At least there was something cool there.

It’s a nice mold.

I can only imagine how many molds Lego uses.

Some girl vandalizing Churchill.

I don’t think that’s the Vietnam Veterans memorial. It’s the tomb of the unknown hot dog.

The models were pretty cool.

And it was a dream come true for Henry.

I need to get one of those for home.

Still having fun…

A girl and her droid.

More steamboats. There was also sunburn and puking.

Shadrach

He has three legs, as do all cats, but is missing the fourth one.

Peter and I cobbled together a simple launcher for paper rockets.

Charlotte counted down from 100.

Harry donned safety gear.

There was a bit of dribbling as well.