Panel Glue Press: The Reluctant Project

I am currently in the middle of a rather interesting project that requires two rather wide panels produced from rather thin stock relative to their width. This project therefore justifies the acquisition of a panel glue press clamping system shown here in the photo. The experienced woodworker will know that wide panels are rather difficult to glue up without having them bow across their width due to uneven clamping pressure applied by typical bar clamps even when those clamps are alternated on both sides of the panel during the glue up process.

I call the project to build a panel glue press a reluctant project because I rushed the production of its large supporting frame through the workshop. I rushed it because even though it will support a client commissioned project, it impacts the timeline for that client commissioned project which in this case just luckily happened to be slightly ahead of schedule.

But if the client based project happens to go south as projects sometimes will, then I may need that extra margin which now is no longer available because I spent it on building the new panel glue press. I think that every woodworker I know who operates his or her organization within any sort of business model must often make workshop upgrades within the time allotted to client based projects without seriously impacting the timeline for those projects. This is often difficult to do.

I rushed through the panel glue press project to minimize the impact it had on an ongoing client based project even though it ultimately improves the quality outcome of that project. The glue press frame turned out well, but with minor flaws that could have been avoided if I had taken more time to complete it with greater care and patience.

I find it somewhat difficult to balance that tradeoff between making a workshop change to benefit a client based project against the time it takes to effect that change though in the end, I usually value a better design or build outcome at the expense of the client project timeline. Communication with the client is very important in this instance. Some people will understand, want a better outcome, and tolerate a minor delay. Some though will emphasize the importance of schedule despite the fact that their project has durable value.

Functional Design and Unintended Consequences

I often design something for one purpose only to have it used for something quite different than that for which it was originally intended. My recent drop leaf drawer unit design has taken that familiar path. I added a drop leaf top to a drawer unit that I had built so that I could use it from the couch as a laptop workstation or alternative dinner table. It spends its time these days doing none of that though.

I have a comfortable leather office chair that sees a lot more use lately because the drop leaf drawer unit that sits beside it now features one of my iPad stands placed atop it. The iPad is held at a perfect viewing angle and height for me while I sit on that leather chair.

The drop leaf extension added to the drawer unit can support my laptop without interfering with the iPad stand while located on the center of the table top. I can use the iPad to look up reference information while using the laptop for design work, a very efficient, compact, and comfortable work solution ergonomically integrating multiple resources which I had not originally intended to combine.

I like functional design not only for its ability to provide solutions to known problem requirements, but also for its ability to open new doors to creativity by providing unintended solutions. I saw this in the pipe organs I built where players with different musical backgrounds would use innovative stop registrations to perform music in ways I had not considered.

More often, we who build things will come up with a unique idea and get the you-cannot-do-it-that-way-because-it-has-never-been-done-before argument back in return. It is refreshing when a design is actually used to do something that has never been done before by someone who is willing to experience things in a fresh, new way.

The Molly Project: Iterations

The Molly Project is an attempt to build a tap dance floor that can be used as a percussive device during the performance of live music by building the floor upon a hollow yet enclosed box.

Molly is a singer and dancer in addition to being both friend and in this case client. One of her requirements is that the floor must be as light as possible yet built to minimum dimensions with certain materials that will enhance its resonant qualities.

My first design iteration had the box constructed of four side aprons joined to corner posts using mortise and tenon joinery. I was doing projects with that construction technique lately so it was natural to begin the design there. But that is not how a box is typically built.

The first true box iteration I explored was based on box joint construction. I built a couple of drawers and a few audio speaker system boxes using that method. I sometimes think of it as a signature style. But I think I am going to settle on another method that has worked well for me in the past. That method is the half blind dovetail.

I have some small speaker boxes I have to complete when time prevails that are built with through dovetails. Through dovetails present a good looking trapezoid profile on one side, yet a not as good looking rectangular profile on the opposing side. Through dovetails are still considered the pinnacle of fine woodworking.

Half blind dovetails present that same good looking and instantly recognizable trapezoid profile on one side. The opposing side is clean across its surface. It is a good look I think in addition to having just about as much prestige as its closely related through dovetail relative.

All of the three traditional box joinery techniques mentioned in this entry qualify for the appropriate strength requirement by presenting enough face grain surface area for gluing. I think I will use the half blind dovetail method on this project. It uniquely represents the principles of fine woodworking inherent in my work.

The Molly Project: Planning Stages

A friend contacted me a few weeks ago asking about the possibility of having me build something for her. Her name is Molly. We soon met to talk over the project and some of its details. It sounded interesting enough that I knew I had to find time to fit it in if I could develop a workable design based on her concept and requirements. I worked out the design, and recently met with her to discuss details and cost. We have a preliminary agreement to build as a result.

I am still working on that large shelving unit project for myself, but its project timeline can slip some though. This project is core to my workshop mission, and the first entries I write here will discuss the build process before I discuss the specific need that this project addresses. It is definitely one of the more interesting projects that I have been asked to be a part of.

Shelving Units: Expecting Too Much Sometimes

The machine pictured here is a combination planer-jointer. It can easily convert between one machine or the other. It is configured as a jointer in the photo here. I love this machine. I also hate this machine sometimes. I purchased it because I was doing smaller work in this not-too-large workshop of mine. It was perfect for that work.

I replaced the combination planer-jointer last summer by dedicated machinery with more accuracy and capacity to handle projects like the large shelving unit side frames pictured below. Yet the planer-jointer stays where it sits because it can surface a board flat that is 10" wide. I use it now almost exclusively in that capacity to surface one side of a board completely flat before running it through the dedicated planer or drum sander. Doing so helped create almost perfectly aligned mortise and tenon joints used in the construction of the shelving unit side frames pictured here. I love it for that reason.

This particular planer-jointer was designed with some limitations that make it more attractive to a woodworker like me with a smaller shop and budget. It has tables made from aluminum rather than cast iron for instance, and only the outfeed table is adjustable using simple set screws which periodically go out of alignment like they did today, and then are rather difficult to adjust. I hate it for that reason.

I like perfection in my machinery and in my work too, but with respect to the planer-jointer, I decided I had to accept the fact that it was not designed to offer perfection, but rather capacity and functionality within the reasonable price I paid for the machine. I therefore pay closer attention to its alignment now, and make adjustments when required. I accept this imperfection because of what the machine can do for me within the limitations of my workshop space and budget. It has a very welcome place here as a result.

Shelving Units: The Engineering Case for Quantifying Quality

Tolerance stack-up is an engineering concept defined as an accumulation of dimensional variations in a part or assembly made up of multiple parts. No part can be made perfect, and many mechanical drawings include dimensions with specified tolerances such as 15.000" +/- 0.005" to convey an acceptable range within which the dimension meets specifications.

The usually accepted tolerance range for most professional woodworkers is +/- 1/64" or  +/- 0.016". This degree of accuracy is not hard to obtain given experience and good equipment. The problem lies in a design that combines multiple parts in such a way that the dimensional variations add or subtract. The accumulation of dimensional variation can become significant if many parts are used to make up a single assembly as in the shelf unit side frames pictured here. Viewed in another way, if four sequentially assembled parts are off by only 1/64", the final accumulated dimension represented by their assembly will be off by 1/16". And that is significant. The same holds true for angular dimensions and perpendicularity.

I am not able to measure the shelf unit side frame diagonals during the glue-up process because the many clamps required interfere with the measurements. I rely on taking measurements with an accurate square in each of the internal frame openings and adjust clamping pressure where required to get good readings. The side frame diagonals are within 1/16" of each other or better when the clamps are removed.

Diagonal measurements within 1/16" or better are generally good enough to consider larger assemblies acceptably square. My designs often rely on ultra-accuracy to insure the overall object assembly comes together well. The Alice Table comes to mind as a good example.

Tolerance stack-ups are analyzed in terms of either a worst case scenario where an assumption is made that all dimensions will end up at one of the outer extremes of the specified tolerance, or statistically where a probable average of variation is assumed. I will often consider my woodworking technique and shop equipment good enough where I assume a probability of small average variation.

I should maybe consider playing it safer the next time I evaluate a particularly complex design by using a rough worst case analysis. It might save an unpleasant surprise. The computer screen might tell me I can build something, but reality might dictate otherwise. So far though, the shelf unit side frames are gluing up well.

Shelving Units: Starting Out

The last two projects I wrote about were items I built for myself. The next few posts will be about a set of four shelving units I started to build this weekend also for myself. I decided that a set of shelves will best and most economically hold my growing collection of integrated technology that includes the computing, audio, and display systems I use in my work and life at home. One of the shelving units will also act as a bookcase.

I had two goals in mind as I set out to design the four shelving units. Each should reflect the quality my workshop is capable of producing so that they properly communicate my design and skill level during their lifespan, and yet the construction of each should attempt to minimize schedule and cost burden as much as possible.

I achieved the first goal by using mortise and tenon joined frame constructions for both side and shelf frames to give the shelving unit assemblies a simple and unified yet professional look. I am going to achieve the second goal by using as many commonly dimensioned parts as possible to minimize machine time and setup. Each shelving unit is therefore part of a product family based on a nearly common product platform.

You know how difficult this winter has been especially if you live and work in the upper Midwest as I do. I made a wood run for the project this morning sorting through a pile of lumber in an enclosed but unheated shed with the air temperature still in single digits looking for boards that were as straight as possible. I quickly stickered them on two even saw horses when I arrived back at the shop to minimize their chance of warping.