Fitting a few panes of glass after vandalism, I measured and subtracted 1/8" off a length & a width for expansion. Popped along to the glaziers, a round trip of 24mls. Gave him the measurements. He asked if I wanted it that size and I confirmed the numbers. He asked if I'd subtracted the 1/8" and I said yes. He cut the panes, 4 or 5 and off I went.
I'd prepared the frames and applied the bedding putty but when I offered up the first piece. I found he'd cut all of them 1/4" too small. Back I went to complain and have the new pane redone at his expense. He seemed surprised to see me return. I went over the measurements again! And what did he say, "When I asked you before whether you'd taken into account expansion and reduced the size. I naturally assumed you were lying to me, because everyone does. And subtracted an 1/8" plus a bit all round for your error. Everybody has a tape but no one knows how to use it."
I assured him I did and gave him the figures for the third time. Explained that he could have the first panes back and that I wasn't going to pay for the replacements, plus I wanted him to stump up for the extra putty I would now need.
He agreed to cut the panes at no extra cost and gave me a tin of putty. But I still had to pay for the extra fuel. I watched as he measured the glass and had to stop him as he nearly cut the first pane 1/4" too small. I then had to check the next four before he cut them. The panes were duly fitted and I had putty left over. An interesting way to spend a morning. But due to his error, it was a more a case of measure once and cut twice, with a bit more measuring in between; 48mls on the road and it threw my schedule out for the rest of the day.