Friday, March 11, 2011

Practice, Theory, and an Angry Inch.

"In theory, there is no difference between theory and practice. In practice, there is." You gotta love Yogi Berra.

The project I'm currently wrapping up has been an exercise in learning real world differences. The project is a stacking bookcase that's designed to wrap around a French doorway. Two lower cases sit on base frames. Two middle cases sit on top of the lower cases. Across the middle cases is a long shelf, and on top of that shelf is another pair of bookcases. It's somewhere around 8 feet tall, and 12 feet wide.

Originally, I thought it would take me a month, maybe a month and a half. But, the problem is that the job was for a friend, and I got carried away on the details. (Frame and panel sides, instead of furniture grade plywood, etc.) Two and a half months later, the thing is finished, and I'm in the process of trying to install it.

Because the tolerances around the thing are fairly snug, there's room to work, but barely, and so I'm having to shim the thing up and down to get everything aligned so it will come together. I took initial measurements, as I mentioned. But what I learned today is that the differences between practice and theory go above and beyond tape measure/ story stick issues. I made the mistaken assumption that I was measuring from a level floor. Silly me. I previously wrote that the door frame had a 7/16" difference in height across its width. But I didn't check to see if it was level. (It is... I checked today.) Across the 12 foot span between the side walls, the floor drops an inch. I figured there would be some variance in the floor contours, but I really wasn't counting on such a drop in altitude. Even if I'd installed leveling legs, (Which I'm totally doing next time) there would still be that missing inch.

The plot thickens.


Anonymous said...

When you say that you've been working on it for 2.5 months, how many hours per week would you say that you put in? I'm about to start a large cabinet project, with frame and panel sides, and I'm trying to estimate how long it will take.

JW said...

In general, they were full time weeks. Towards the end, they were more than that.

If you consider that every frame and panel section replaces a plywood panel, the job is pretty easy to break down. First half, figure out how much time it'll be to mill up the frames and panels, join them all, smooth out the joints, and sand everything. 8 full panels, plus the F/P shelf that spans the two stacks, took me a few weeks worth of milling and fussing about. This takes a lot more time than cutting plywood panels. The second half is a normal cabinet job once you have your side panels, doors, etc... and providing you don't have to re-make any of the F/P sections that you built.

Bear in mind, I also have a lot of weird stuff going on in this project, and that's where some of the time went. In part, some of the design was the result of needing small enough boxes to get past a really awkward stairwell. And everthing was designed to be removable when the client eventually decides to move out, instead of being permanently installed... meaning that the sides that were up against a wall had to look good, too, even if they won't be seen for years.

Bottom cases were built to be stand-alone, with mitered base frames and crown, and a thick top with mitered molding. On top of those sit the middle cases, again with base moldings, which had to be basically scribed to the top surfaces of the bottom cases, so that everything would sit plumb, without gaps. Then there's a shelf that spans the two stacks, and some boxes on top of that, all of which had to be fitted together. Aside from 2 French cleats in the middle layer to help prevent tipping, this whole thing is basically free-standing.

Typical cabinet jobs are a little simpler.

Anonymous said...

Thanks for your answer and for a great blog.

-Chris Foran (Ottawa, Canada)