Categories
Idle Tech

Extending the life of an old TV

Paula and I bought our first flat panel HDTV back in 2005. The 32″ Samsung was initially installed in our San Jose kitchen before making the trip to Dublin, Ireland and the finally to out home in Bellevue. Back in early 2011 we started noticing some weird artifacts on the screen, it looked like the TV was switching all the images to 8-bit color.

TiVo screen showing compression error
Do you like the left or right better?

It’s not the biggest TV at 32″ and it’s only 720p, but it fits perfectly in our bookshelf so I decided I’d try to fix it. I’m no electrical engineer, but I have a screw driver and an inquisitive spirit. What else would I need… other than a night in a Holiday Inn Express?

I started trying to debug it and pretty quickly came to the conclusion it was a heat issue. My first guess was dust had built up on a heat sink somewhere inside the set. I couldn’t see anything obvious through the vents in the top or bottom, but I tried a few blasts of compressed air to see if it changed anything. It didn’t. If I couldn’t clean it from the outside I’d clean it from the inside, so I opened up the TV. I learned something that is probably obvious to most: opening up a television is a lot like popping the hood on a broken car… it’s satisfying but also pointless act for 99% of the population (and I’m certainly not in the 1%).

What did I find when I opened up the TV? What I didn’t find was dirt. Sure, it was a little dusty, but nothing that looked like it would be choking the life out of our TV. I was, however still convinced the issue was cooling I decided to try increasing the airflow. My plan was simple, slap some small PC case fans on the top of the TV and block off the rest of the top vents to make sure air was pulled from the bottom and not just flowing in from around the fans.

Armed with a sheet of black polypropylene from TAP Plastics and a set of four 50mm case fans I went to work on my TV. I carved up the plastic, screwed the fans in place then duct taped the whole thing to the top of the TV. My improvised fan and baffle worked (almost) perfectly, the TV can now run as long as we like without the picture going all wonky on us.

I say it was “almost” perfect because it was a prototype… the plastic was too thin and the duct tape wasn’t a great hold and had to be redone every couple months. It was, however, good enough that it was on the back of the TV keeping it going for the past three years.

Comparison picture of thin polypropylene to thicker acrylic.
New baffle will be much more rigid

The solution was great in concept but lacking in execution. It was high time to turn the prototype into a finished product so I headed back to TAP plastics and picked up a piece of scrap acrylic for the bargain price of $0. Because I already had a great template in the form of the prototype it was quick to transfer to the new plastic stock.

The finished product is solidly built and screwed directly to the TV (no more slipping!). It actually has way more attention to detail than a hidden hack has any right to be. I suppose I’ll just have to spend more time looking at the back of our TV.

Fans mounted on TV

Categories
Art Idle

Quick home foundry to melt aluminium

Today I decided to take a creative break and turn our old Weber grill into a foundry… because who doesn’t want to melt down old hard drives and turn them into art?

Aluminum ring
A quick and dirty “ring” cast from aluminium

There are a number of ways to build a home forge using paint cans, flower pots, chimney pipes and more, but while planning out my strategy last night I came across a YouTube video by “LifeBuzzN” which used an old grill. Our old grill sitting behind the trash cans was just asking to get the treatment. First to Goodwill to pick up an old hair dryer then a quick trip to Home Depot (and then the requisite second trip to get the part I overlooked) and I was ready to go.

Grill turned into a foundry
Home foundry courtesy of Weber and Vidal Sassoon

The setup is pretty simple, 1.5″ pipe is bolted to the bottom of the grill and an old hair dryer acts as an always-on bellows to get the coals extra hot. I used an old cast iron pot I also picked up at Goodwill to act as my crucible. After a half a day of tinkering and learning I figured out just what was needed to turn old hard drives into aluminum mini-muffins (ingots, if you must).

Aluminum ingots cast in a muffin tin
Aluminium ingots ready for reheating and casting.

Since I had the forge going and a bunch of molten metal I had to try a quick casting. I made a hasty form out of some foam insulation and buried it in a bucket of sand. This “lost foam” casting process is quick and easy, leveraging the low boiling point of foam to have it boil away when molten metal is poured in. If you’re careful with your foam form and use a coating to keep the sand out you can get really clean results. I wasn’t careful, I was just to enthusiastic to try out my new toy. The result wasn’t pretty, but it was mine.

Cast aluminum ring held in pliers
My aluminum ring with sprue still attached.

 

Next up I’m going to try getting refined and use the lost wax casting process. I’ve ordered some casting wax from Amazon, so I should be ready to try to create something a bit more refined this weekend.