|Forum topic by Charlie||posted 06-06-2012 05:40 PM||1206 views||0 times favorited||9 replies|
06-06-2012 05:40 PM
My kitchen remodel involves installation of Blum Tandembox drawers. While they do provide some SAE equivalents, they are primarily a metric system. The conversions don’t work out exactly. I was cutting a piece of 1/2 inch plywood on my table saw and checking to see if everything was square, making little adjustments, etc. I had ONE tape measure that was marked in both SAE and metric.
I checked my crosscut sled. Good
How does it cut? Smoooooth. OK so I start measuring the piece I’m cutting. Using the metric side of the tape. Keeps showing me a 3mm taper in about 14 inches. Huh?
Recheck this and that. Adjust this and that. Try the crosscut sled again.
Long story short, it was the way I was holding the tape! The hook measures differently if you tilt the tape over to one side. The piece is square as it can be. I was using the TAPE wrong! Or expecting too much.
So I measure out 120mm from fence to blade. Make a cut. Measure piece. It’s 123mm.
Tape measures are made to measure OUTSIDE, not INSIDE, and the hook on the end was adding 3mm.
OK, I’ve had enough. I went to Lowes and bought a “yardstick” marked in mm and cm, and a digital caliper that does both metric and SAE.
My reasoning is that this drawer system is metric. They make reference to SAE equivalents in the instructions, but when you start adding things up in SAE, they get farther and farther off from the metric measurements. I’m not going to be crazy obsessed (I do that easily), but I know these drawer systems expect pretty tight tolerances and the closer I can get to being right on, the better time I’ll have installing everything.
So I bought a couple of more accurate measuring tools for the work. I don’t think that’s crazy. :)
Moral of the story: Don’t take something as simple as measuring for granted. Tapes measure outside. Rules measure inside.
The upside of this little adventure is that my saw is now off my about 1/2 of a mm in 12 feet! :)