Quote Bwillie: ”Looking at these dividers reminds me that I always struggle here to get the dimensions spot on. Especially since I use felt on the ends that touch the sides of the box, I have to account for those. Usually on every box on some portion of the dividers I compound an error, and before I know it, I’m all out of whack.”
When I read this comment in my last episode in this series, it caused me pause. What Bill was describing was exactly my experience; small errors compounding each other until the divider grid was nowhere near perfect. I don’t know if Bill could observe these errors or just being honest about his own experience.
However, as I hold him in high esteem as a box maker, I decided to re-make my divider grid. And to be honest about this second attempt, it was no more successful. There it was again, not quite perfect, joints that didn’t quite fit, and segments that were out of square. Now I’m not talking about large errors, in fact they were so small, I couldn’t photograph them for this blog – when I tried, they didn’t show.
Some of my best wood working is done in bed. I normally fall asleep at night thinking about my current project. Often I rehearse in my mind the steps I need to take next in a project. That’s when it occurred to me. It I cut all of the half-lap dadoes at the same time with each like piece ganged up against the next, make one pass over the dado blade, move to the next cut, (ie. notch), then each would have to line up with the next. So that’s exactly what I did and it worked.
Below I have lined up all of the component parts for the lower dividers to test for fit and accuracy.
I still found it easy to make a mistake during assembly, because, although each piece in theory was the same end for end, I found in practice this wasn’t quite the case. A discrepancy of .025mm is enough to throw things out and that is the kind of mismatch I’m talking about when you flip a piece end for end – not much, but enough to spoil a good fit.
To avoid this, I drew arrows and made notes on the bottom of each piece. I needed to be certain that the advantage gained by cutting all of the dadoes together wasn’t lost by inadvertently swapping one piece end for end.
Close-up showing markings to avoid confusion.
The fit is so exact and snug, I only glued up the perimeter pieces.
Here’s the third and final attempt. If I do say so myself, it’s a perfect fit, and absolutely square at all intersections of the dividers.
-- CanuckDon "I just love small wooden boxes!" http://www.hillsbiblechurch.org/