The installation of the wood floor in the Music Room is now in full swing, for real this time. Here are three perspectives of first twelve diamonds:
Despite the awful spectrum of the mercury-vapor work lamp, these images do show how the wood appears to change color as one moves around the room. It should be even more dramatic once the wood is finished.
So, what makes this such a challenge to install? Read on…
As you can see, each rhombus is composed of 12 boards. At every shared edge, one rhombus presents a single board (which is the definition of straight) and the other presents 12 individual edges which must be cut at an angle and must all line up, both one with another and with the straight edge. Moreover, symmetry dictates that when there are twelve edges on one side, there are twelve edges on the opposite side, which has the effect of doubling any angular error that may exist in cutting these edges. Last week the initial plan was to try to just be very precise, using a jig to get precisely repeatable measurements and just put the floor together, 12 perfect boards at a time. A photo from last week shows such such diamonds:
While those two diamonds did look and measure perfectly, the third diamond showed that we were off by 1/16″, which is approximately 7/100ths of a degree, and we don’t have any tools that can be trusted to measuring and/or setting angles to less than 1/10th of a degree. Nor can we trust that the saw itself will bite into the wood and deliver a cut that’s better that 1/10th of a degree. And should this be a surprise? That’s only 5/1,000ths of an inch across the 4″ diagonal length of the cut of each board. To put that into perspective, that’s 1/3rd smaller than the feature size of the first integrated circuits. It’s not a number one can manage with a table saw.
One of the team went back to the drawing board, or, more precisely, back to his kitchen table to discuss the problem with his daughter, who is majoring in mathematics. She pointed out that equilateral triangles have a marvelous property, which is that they are easy to construct, and when done at large scale, can provide exceptionally accurate 60° angles. This idea was confirmed by Wes Lachot, and a new program was put into place. In the following photo you can see three 8′ long planks screwed into the floor (at different places):
When the time comes, those three boards can construction an equilateral triangle that’s ±1/64th of an inch at each corner. Granting a total error of 1/32nd of an inch, or less than 2/100ths of a degree. Not only that, but the edges can be used as guides against which both the straight edges and the 12-edged edges can be made to agree, and thus our pattern does not diverge as before, but rather follows the template we set for it. In integrated circuit terms, that’s only 1/3rd larger than the minimum feature size of the Intel 4004 microprocessor across the 4″ diagonal of our boards. And that has put us into production mode:
And an alternate view:
Moving along, the Control Room is seeing a lot of action as well, presently from the team that does the acoustic finish work. Here’s the latest at the back of the Control Room:
Above you can see that our TopAkoustic material is so smooth that it reflects the light refracted by the glass blocks as if it were a mirror. But it’s not. You’ll never see this in normal light, but the flash exposes the structure that makes this material an excellent acoustic absorber:
Here are two views showing the 705 rigid insulation now filling the inside of the front control room walls:
Two different opportunities to look into the Music Room! And here’s the other side, looking through Sound Lock 2 into the eQuipment Room:
Outside, the Loggia has now received all its storefront material:
And finally, a check in to see whether it looks like we’re on track for the end of the year. With 10 weeks left in the calendar (8 if you don’t count the Thanksgiving and Christmas holidays), 8-10 weeks ago we were finishing up the Trough Drain and framing the soffits for the booths and the Control Room. We’ve certainly closed the door on the trough drain:
But we have yet to finish all the concrete work. And while we do expect to finish up the trim work in the Control Room in the next few weeks, we haven’t started to trim out the booths. So it’s a challenge, but we are accelerating, so we may yet make our date.
2 thoughts on “Week 146 (Music Room Floor, Part 1)”