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Designs Explored - A Trestle Table Design Broken Down
By Kevin Sullivan

Click on any picture to see a larger version.


I have wanted to build a trestle style farmhouse table for a while and designing the table seemed so overly simple. Why not just make the mortises 1 inch, 25 mm wide? I could make the posts 3 inches, 75 mm square. It works. It is simple. If one is skilled to an extent, they could probably make one and never draw plans.

While thinking about this project, I couldn't help but run across many of the trestle table designs available on internet image search results and videos. I noticed so many of the pieces had slightly different dimensions. Almost no designers or builders used the square block design. Their measurements were nearly arbitrary, yet many looked nice. How did they do it?

A distinction needs to be made before moving forward; I wanted to design a trestle table that could look good standing on its own. If I were designing a table for a specific room I would handle things differently. I would balance my measurements off the proportions of the room.

I designed a few versions of the trestle table before I feel I got it close to where I am comfortable sharing this design. In this case study of design we need to start with at least one dimension and a ratio to balance everything around. For my first design, I used the Golden Ratio, 1.618. I knew a dining table had to be a certain height, 30 inches or 764 mm, which is most typical in modern construction. We can take that dimension and multiply it by 1.618 and get our width, about 48.5 inches, 1236 mm. Multiply it again and get our length, nearly 78.75 inches, 2000 mm. It is a visually pleasing volume on the page, and likewise in a room, but in a dining room in a home I can afford, 48 inches is a bit wide. A length of 78 inches is a bit short for entertaining even my immediate family, let alone in-laws, children, nieces and nephews. Visually pleasing, functionally inadequate.

I interject to say measuring or cutting to a specific 1236 millimeters may be a little lofty for some of us. I reference the nearest millimeter in this article for those who want to check their arithmetic. This is woodworking, take some personal liberties when making your own project and measure and cut to the nearest 1/8 inch, or even whole centimeter, if it is more appealing to work like that. Moving on...

“What size does work?”

A table that is a bit narrower at 44 inches, 1120 mm wide and 96 inches, 2438 mm long would be great.

We can stick with the 30 inch, 764 mm start point and change the ratio from 1.618 to 1.21. The math does not work in exact increments from one to the next of 30, to 44, to 96. It does, however, hit close to those numbers over a series of increments, missing the 96 mark at about 94.375 inches, or 2397 mm. As Vonnegut might say, “So it goes.” Or cut your table to be 96 inches and don't tell anyone.

A quick and easy way to figure out these steps and have them around for quick reference is to create a spreadsheet in a software. One could also spend a minute or two multiplying or dividing 30 inches, 764 mm, by 1.21, writing the answers as they go. For our sake, see Figure 1.

Figure 1.

This gets us the overall table, seen in Figure 2.
Figure 2.

Notice the width, 1139 mm, is not what our spreadsheet specifies, which is 1119 mm. Let's discuss why that number is different, and why it may work well in this situation.

For starters, that is 2 centimeters, about 3/4 of an inch, less than 2% of the width. We can compromise because we are going to pick up some aesthetics with what we have going on with the boards that make up the top. The boards in the center are not all the same width. The center board is 201 mm wide. The two boards bordering that are 166 mm wide. Out from that is two boards at 137 mm wide. The outermost boards are again 166 mm wide. Our breadboard end is 166 mm wide.

All these numbers come from our chart and it gives our table's top a visual appeal. Conversely, one could cut 3 mm off each of the widths of the boards and get 1 mm off that 1119 mm overall width and likely not notice the difference.

Our result breaks the grain of the top such that it conforms with the rest of the features of the table. It also allows for different woods or woods with different stains to be used and sized in a way that is, again, visually appealing.

Moving down to the feet and the legs we will consult Figure 3 and Figure 4.

Figure 3.

Figure 4.

The angled leg brace is 344 mm long, or at least the section we will see once the table is finished is this long. 344, that doesn't seem to work. It's not going to be laying flat when it is finished, it will be on a 45 degree angle. It's actually going to stand about 243 mm vertically. Consult the chart, and it works.

The angle brace could be adjusted. Shorten the long 344 mm edge so it is only about 307 mm, and stands 217 mm tall when on the table. 217 does not work, but add it to the 78 mm height of the base footing, and they work together quite nicely, standing at a combined 295 mm. Or make that long length a number similar to something in the chart.

Even the measurements from our center beam come from the chart. The center beam is 1637 mm (chart says 1638, so it goes), 114 mm tall and 64 mm wide. If you wanted to pick two closer numbers on the chart, go for it.

In one version of this model, I went so crazy as to make the mortises dimensions from the chart. That was too much, in this case, and really doesn't make any sense. Since the mortises in this design are not going to be seen, it would make more sense for the person building this table to stick with some dimensions that corroborate with their tooling. Example, a mortise width of 3/4 inch to 1-1/4 inch, 32 mm in this case, mortise to pair with a specific chisel in your arsenal should be fine.

One could also break this project down a tad, and use the Golden Ratio, or any other ratio, to design the legs in relation to the 30 inch height, or any other measurement. In this case, the top could be however big it is going to be and our designer not be overly concerned about it. Like we discussed with the top before, the designer could still use a ratio, likely the same as on their legs, to divide the center boards on the top to specific widths that add a visual appeal to the top. The length of the top could determine the breadboard widths.

I'll spare walking through the rest of the parts, and leave it more as an exercise for those of you who found this interesting and worthwhile. Keep in mind, some parts are somewhat arbitrary because they work with something else to complete an aesthetic across a distance not dimensioned in the drawings. I intentionally broke a few rules of dimensioning (sorry Dr. D.). When making the table parts myself, I know how I will have to locate that feature and it will not involve a granite surface plate and a couple hundred dollars worth of instruments to locate a hole. I will most likely be using hand tools.

Designing something like this, with features increasing and decreasing in size incrementally, doesn't have to happen in 1/2 inch or 10 mm increments. We can easily move away from that and get an array of dimensions that will give us plenty of options to choose from, that will also be visually pleasing. The intention of this exercise is to design aesthetically pleasing standalone furniture.

Moving forward, one could apply the same ratio to a whole room of furniture, only changing that base value. This practice allows one to uncover a sort of style of sizing of features that can help someone more easily make a room full of furniture look nicely together.

I am the designer of the drawings for the table and I am including them for free distribution. Use them as you see fit in your personal work.


Kevin Sullivan is a high school Applied Technology teacher. Along with engineering, engines and automotive courses, he has taught woodshop courses in his high school on and off for eight or so years. He has experience working with hand tools, power tools, and CNC. His first foray into woodworking was building an electric bass guitar in high school and he has been hooked ever since. He can be reached directly via email at atwiniam@gmail.com.

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