Sunday, May 06, 2007

Monitor cross-bar

Now here's a thing. After a year or so in the shed, wood warps. No, really, I kid you not. You thought it was machined nice and straight and it would stay that way? not so.

Net result is the cross-bar that holds the monitor in place and prevents it sliding off the angled supports, despite being precisely cut by a delightful if grumpy old giffer at B&Q, looked too short. However, I know I measured the cuts and they were right on.

Taking a good look at the wood, I could see it had bowed out between the hinges of the back door. So the quesion is, go with the bow and leave a bit of naked screw thread hanging in a gap, or take the opportunithy to pull things together and try to reverse the process?

I believe that, a bit like Jenga, it's best to keep things as straight and precise as you can, for as long as you can get away with it. Once things get wonky and you start operating (with some imprecision) relative to a wonky reference, it gets messy in a hurry. So I decided to pull things into shape.

At this point, I had to ask Jenny to lend a hand because, having fitted the back door, I couldn't now reach around it to push in the side of the cabinet whilst holding the cross-bar in position for tacking. I was glad to be able to involve her.

Having tacked both sides, I set about getting the left side screwed in properly, with pilot holes and countersinks. Once this was done, it was time to try for the other side. What I have found with tacking is that it tends to leave a gap because the screw is threadding its way throuih the first piece of wood, but dos not immediately catch onto the adjoining piece so, for a turn or so, it pushes the second piece away, leaving a gap.

This isn't normally a problem as the objective is to hold the other end of the wood in place whilst you are properly and precisely fixing the first screws - it just stops it moving around and getting damaged. The end you are working on can generally be unscrewed and re-tacked, this time without a gap, whilst you seat the first screw.

In this case, the door got in the way again, and Jenny was into her dress-making so I didn't want to disturd her. Given that one side was already screwed in flat, I decided to lie the cabinet on its side and put the monitor on top. Needless to say, the weight of the screen was certainly enough to apply the necessary pressure to finish the job.

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