Archive for the ‘Tools’ Category
I just finished a simple carpentry job: drilling a 4 cm hole through a 6 cm desk for a connector on the end of a PC video cable to go through. My 16-year old son worked with me, and made any number of helpful comments to save us making errors. We avoided most of those errors thanks to him. Part of the story is that risk identification isn’t enough — there has to be risk analysis (likelihood and expected cost), risk prevention planning (pre-plan for how to avoid the risk becoming a reality) and mitigation planning (pre-planning what we will do if the risk does become a reality). And estimate the cost of fixing as feedback a recheck on the original cost in the risk analysis. Needless to say, I didn’t complete all steps for all risks, and some damages did occur. I made an arc-shaped scratch on the top surface of the desk, and a piece of bottom surface wood detached under the desk. There are many steps in risk analysis and people often check it off as done after doing just the risk identification.
But that wasn’t really the point of the story. The point of the story is related to one of the risks my son identified: “Dad, the circular saw is not deep enough to cut through the entire desk thickness.” I responded, “Good point — I’ll have to complete the circular cut from the bottom after doing most of it from the top. At least the saw is deeper than half the desk, so it should work out.” But after a successful half-cutting from the top, when I went under the desk I realized the significance of something else my son had pointed out. He had said, “Dad, the circular frame for the circular saw is a larger diameter. You won’t be able to cut from the bottom because you’ll hit the drawer frame under there.” For that risk I also had an answer: “OK, I’ll do the entire cut from the top.” (More about risk analysis: mitigation plans must all be cross-checked to make sure none contradict.)
Realizing that I wouldn’t be able to complete the job from under the desk, I went back to the top of the desk and figured (totally illogically — just emotions here) I might as well cut as deep as the saw will let me go, and then figure out what to do next. Fine — I got another 3 mm and then the circular frame for the circular saw made contact with the smooth desk surface and made that arc-shaped scratch. My son was not happy, but he forgave me.
But here’s the point. The right response to the “saw isn’t deep enough to cut through the desk” would have been simply, stop, go to the store with the saw as example and the desk measurement, and buy a deeper blade or circular saw set. Then come back and do the job with the right tool.
But since it was Independence Day and (I assumed that) the stores were closed, I forged on using a set of hand chisels. Fun enough. Nostalgic for the days of my youth when carpentry was without power tools. I did succeed. Took an hour instead of 2 minutes. The hole is correct and smooth but not as close to perfect as if done with a circular saw. And yes, the chiseling is what detached the piece of wood from the bottom surface of the desk, though circular saws can do that too if you’re not careful.