Tuesday, June 2, 2009

Converting our old entertainment center to HD

It's a common problem, of course. Our old entertainment center was sized for the TVs of yesteryear. We bought it when we bought our first house (in Schenectady NY) and we've dragged it along ever since -- Bill (Thing 1 for long-time readers) was less than 2 years old when we first set it up, and Thing 2 was probably 3 or 4 when we bought our last TV, a whopping 31" set, the largest that would fit into the "hole" in the middle.

Times change, sets have grown, and worst of all, the aspect ratio has changed. Now, some of our favorite shows are shot in 16:9 and the huge 31" screen is whittled away with letterboxing; 2001 was a thin stripe given its 2.3:1 aspect ratio.

So, we wanted a new set. The aspect ratio made it tough -- a set that was small enough for the space wouldn't have a screen appreciably larger, although it would be wider so that l'boxed shows would look better. But size always trumps common sense.

The other problem was that I didn't want to move the contents of the entertainment center; I'm embarrassed to show the whole thing, but there are records (LPs), cassettes, books (mostly graphic novels and coffee table books), ancient stereo components, laser disks, and much more. Most of the possible replacements lack the sheer capacity, and I was worried that we would succumb to creeping upgrade syndrome -- make a single change and everything else needs to be updated and improved to match. Let's see: new stereo, new DVD, digitize the old records and tapes -- it was too much to consider.

Luckily, I realized we didn't need the TV to fit in the hole -- if it covered it, that was probably sufficient. First I considered extending the shelf outwards -- a simple addition of some plywood and trim, probably. But this wouldn't be quite large enough for the TV of our dreams. I could let the TV overlap the clunky edging, gaining a few inches of width and height, but any more and the TV would block the stereo doors and the components on either side. I also realized that the TV would be difficult to reposition, and given the reduced viewing angle of an LCD TV, it would be difficult to watch while exercising (hah! as if that was likely). A movable arm would be the perfect solution and would allow us to get the seemingly huge 46" set of our dreams. In normal use, the TV would float in front of the hole -- it looks surprisingly good that way -- but could be shifted for access to the components or the storage above and below the hole.

And I love an engineering challenge -- it makes me feel like a real man. After much thinking, I managed to solve the problem of where to mount the arm with scrap plywood. The two columns are unneeded bookshelves (leftovers from when we used two of our bookcases for paperbacks and could fit the shelves 8 or so inches apart instead of at hardcover-friendly intervals). To make sure they were stiff enough -- the arm and TV are close to 100 lbs and much of that weight might be extended close to 26", I used a stack of plywood offcuts (roughly 1-1/2" by 3") strips of plywood to reinforce each piece vertically. There's also a long piece of hardwood next to each stack, although I can't remember why it thought this was necessary -- probably to counteract any tendency to creep under load. The columns ended up with a shallow "T" cross-section. They were assembled with lots of screws and glue, although the shelves were previously finished so the reinforcement is mostly mechanical. The shelves were already edged (on the front) with a nice oak bullnose, so they only needed to be cut to fit the height of the hole. It's an interference fit even without the sag caused by the weight of the laser disks above the hole -- probably not necessary, but I thought it would help reinforce things.

After I made the columns, I mounted 2x6 blocks (more scrap) at the top and bottom of the hole, set back about 5" to accommodate the folded thickness of the arm. There's an inch or so between the columns for cables, and to avoid the need to join the two shelves. I used a heavy rawhide-headed hammer to "adjust" (bash) the columns into place. Rows of screws attach each column to the blocks, and the blocks in turn are screwed to the shelves above and below. I ran a few screws through the top shelf into the top block -- screws have lousy holding power in particleboard and I wanted to make sure that the block wasn't pulled out by the weight of the arm and TV.

The end result is exactly what I wanted -- the arm can be fully extended and the TV turned to face the treadmill, or placed back against the entertainment center -- the set is only a few inches thick. The arm also allows us to tilt the TV if Wii users want to set on the floor (the controller cable is only 6' long, although an extension cable is likely to be ordered soon).
The arm also gives me full access to the connectors on the back of the set; a real luxury after years of reach-behinds and precarious set rotations.

Warning: our entertainment center is really heavy (the main piece is about 55" wide) and is loaded with lots of really heavy stuff. It doesn't shift a bit when the TV is fully extended, but even so, I plan to add a strap to keep the whole thing from tipping over in the unlikely event that someone trips, catches the arm and adds his body weight to the lever arm. Or if a visiting child decides to do pull-ups on the arm. Anyone that tries to duplicate this arrangement do so at his or her own risk, and should attach their entertainment center securely to the wall.

Details:

Columns: roughly 9" x 25" each, oak plywood with reinforcements.
Screws: Spax. #8x2"
Arm: Sanus Systems, 26" max extension. Mounted with the supplied lag screws, but through bolts might have been better.
TV: Samsung LN46B640
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