Large Egg Made From a Single 2x4

On the Instructables website I saw the "One board contest". In the description of the contest it said: "We want to see how you can maximize material usage through smart, efficient designs."

It made me think: what can I make from a single 2x4 framing stud, using the entire stud efficiently?

While I was thinking about what I could make, I was looking out of the window and our chicken came to sit just in front of me. I thought: I am going to make a large egg from a single 2x4 and try to make it as large as possible.

If I would make the egg of solid wood, the egg would not be very large, so I decided to make a hollow egg by cutting the 2x4 in many small pieces and gluing them all together.

Wouldn't it be easier to start with eight 1x1s instead of a 2x4?

Yes. Absolutely!

But the contest is about making something from a single framing stud, so buying eight 1x1" studs would not be in line with the intention of the contest. Therefore I bought a single 2x4.

Do I need this egg?

No, of course not. I just liked the challenge to design and build something large from a limited amount of materials.

I am also not really sure what I am going to do with the egg. I like it the way it is already. I could add a simple light or I could use the egg to store something inside, for example some colorful wool for knitting. Or I could put a plant inside and let it grow through the openings of the egg.

But I am thinking to make something that is hanging in the middle of the egg, for example a butterfly or a bird with a lot of color. Or maybe I will make more than one butterfly or bird and let them fly inside and around of the egg. Anyway, that is something for the future.

I wanted to maximize the size of my egg, so let me explain how I calculated the size of the egg that I am going to build. (If you do not like math, just skip this step and continue reading at step 2.)

I am going to buy a 2x4 with the standard sizes of 4.4 cm x 9.6 cm x 240 cm. The volume of wood at the start of the project is therefore 4.4 x 9.6 x 240 = 10,138 cm3

Since I am going to cut the 2x4 into many small pieces, I estimated that I would loose about 10% of the wood as saw dust, so that would leave me roughly 9,000 cm3 of wood in small pieces.

I am going to cut my pieces 2 cm thick, so the thickness of my egg shell will be 2 cm and that gives me 9,000/2= 4,500 cm2 as surface area of my egg that will actually be wood. The rest will be gaps.

Now I had to calculate the surface area of an egg. I had no idea how to do that, so I looked on the internet for an egg size calculator. I tried some dimensions and decided to go for the values you see on the screen shot. When my egg is 66 cm (26") high and 46 cm (18") in diameter, the surface of the egg will be 8,662 cm2. This is almost double compared with the estimated 4,500 cm2 that I have available as pieces of wood, so only 50% of my egg surface will be wood and the rest will remain open.

This looks challenging but I think it is possible.

I am a beginner in using Tinkercad, but decided to use it to make some drawings to help me check the size of my egg.

The first drawing is to visualize the egg that I could make if it would be solid wood. My 2x4 is 240 cm long, so if I would cut it in eight pieces of 30 cm long and place them as the red and blue pieces on the drawing, I would get a solid box of 20x20x30 cm (8x8x12"). If I made an egg from that, the egg would be 30 cm (12") high.

With a hollow egg, the size can be much larger. I wanted to do that by making rings of wood with many openings in between and just enough overlap between the pieces to be able to glue them together. In the second drawing you see that I sliced the eggs to make many rings.

I made the third drawing to compare the size of my hollow egg of 66 cm (26") high next to the size of the solid egg of 30 cm (12") high. It demonstrates how much larger my egg can be if I maximize the size by thinking about the design.

My shopping list for this project was quite short. I just needed to buy 1 single two-by-four.

Two by four inch would be 50x100 mm, but that is not a standard size here in The Netherlands. So I bought the standard size which comes closest and that was 44x96 mm.

The shop had 2x4s in three different lengths: 210 cm, 270 cm and 330 cm. The longest one would not fit in the car anyway, so I had to chose one of the other two lengths. I checked what the standard length of a 2x4 is and according to the internet that length is 96 inches. That is just slightly longer than a standard length which we normally have and that is 240 cm. Since the shop did not sell 2x4s of 240 cm long, I decided to buy one of 270 cm long and to cut it to 240 cm to really start my project with a standard 2x4.

Fortunately my 2x4 of 270 cm just fits in the car without touching the wind screen.

I cut two pieces of 15 cm each off the 2x4 which I bought. Since I started with 270 cm, I ended up with the standard length of 240 cm or almost 96 inches.

The two pieces of 15 cm each might be used in one of my next projects. I did not want to use them to make the egg because I only wanted to use the material of the standard length of a 2x4.

I used a small circular saw with a guide rail attached to it and started cutting the wood.

I used clamps to clamp the 2x4 to the workbench and first made intermittent cuts leaving the clamps in place and after that I relocated the clamps and made the rest of the cut. Then I rotated the wood, made the next cuts and so on. It works best to first make a shallow cut and then a deeper cut as the saw struggles a bit to make a deep cut in one go. This probably has to do with the fact that I am cutting parallel with the grain.

If you look at all the photos you see that the shaded area in our yard is getting smaller as the sun is rising higher, so you can see all of this cutting took some time. It took about one and a half hour to make eight 1x1s out of the single 2x4.

With a table saw this cutting would have gone much faster, but I do not have a table saw. Fortunately I do have a circular saw, because cutting the wood with hand tools only would have been a real workout.

On the photos above you can see that I now have 8 pieces of approximately 1x1" (actually 21x21 mm) and two thin strips of wood. I did not use those thin strips, so besides the saw dust, these strips are the only part of the 2x4 that I did not use.

I enjoyed making the 1x1s outside, because it was a sunny winter day after several weeks with lots of rain.

After all the cutting from the previous step, it was now time for some variation: more cutting but with another saw. I did not measure the pieces and just randomly cut them into short pieces. The shortest ones ware about 2" and the longest ones about 5".

I made this jig a few years ago based on these instructions:

MAX CUT 2 Circular Saw Crosscut & Miter Jig : 11 Steps (with Pictures) - Instructables

The wood had rough sides from all the cutting, so it was time for sanding.

My routine was:

• Sand all four long sides and edges.
• Sand the edges of the first short side.
• Sand the edges of the other short side.
• Sand the flat side of the short sides.
• Put the finished piece in the bucket.
• Grab the next piece and repeat the procedure.

I could do 2 pieces per minute and I had many pieces, so sanding all the pieces took about 2 hours. I do recommend to make sure the pieces are sanded well, so they are smooth, because when all pieces are glued together it is much harder to do any sanding.

Anyway, I was very happy that I have a sanding machine...

I wanted to know how many pieces I had exactly to check if there are enough pieces to make my egg. I placed all pieces on a towel grouped by 25 in a row, so it would be easy to count all the pieces. There are 10 rows of 25 pieces and 6 remaining pieces so in total there are 256 pieces.

You can also see a photo of the side of the pieces. The shape is not a perfect square. This is because my small circular saw tended to tilt a bit when I was cutting.

Fortunately an egg does not have to be square...

In this step and in the next step I show my drawings of the egg. I made these drawings on large pieces of cardboard on a scale of 1:1, so the actual size. In this step you see the top view and in the next step the side view.

I drew several circles with different diameters and I checked how many pieces fit in each circle. This gives me an idea about how many pieces of wood will be needed for each row of my egg.

Only for the lowest row I will fill the entire circle with pieces of wood, so the egg gets a flat base and does not roll over.

Here I drew an egg based on the dimensions I determined in step 1 and 2, so 66 cm high and 46 cm in diameter.

I drew a vertical line through the center of the egg and divided it in steps of 2 cm each, because that is the size of my pieces of wood. I numbered the rows from the bottom up and measured the diameter of each row.

Example: row 14 has a diameter of 46 cm. I checked in the drawing with all the circles that in a circle of 46 cm diameter there will fit 16 pieces. On the second photo of the drawing you can see in red how many pieces will go in each row if I place them with only a small gap between the pieces.

I used a calculator to add up all the red numbers and came to a result of 405 pieces.

I only have 256 pieces, so it is clear that I have to use many gaps. This is as expected, because in step one I already calculated that about 50% of my egg could be wood and the rest would have to be gaps.

I decided to start with as many gaps as possible and if I end up with left over pieces, I will glue them in the gaps.

If I make a ring of 2 rows, the pieces in this ring are overlapping, so I can glue them together. Then I can skip 2 rows, only using 4 pieces per row to gain height and glue the next ring to these pieces. This will become clear in the next steps as now it is finally time to start the assembly.

I collected all of my clamps that I could use in this project, because there is a lot of gluing to be done.

Then I looked on my plan and I wanted to combine row 1 and 2 to give the egg a flat bottom. Row 2 had to be 23 cm in diameter so I placed several pieces on a circle of that size. Then I added wood glue on all the joints and clamped all the pieces together. The vertical piece on the photo is not glued to the rest. It is just there to help me place the clamps on all the joints.

As I wanted to use many gaps in the egg, I made several rows with just 4 pieces per row. On the photos above I made row 3&4. I looked on the drawing how the diameter of the egg was increasing in these rows and glued 4 sets of 2 pieces so they would fit the shape of the egg at this point. (Later when I knew that I had some leftover pieces, I added 4 additional sets of 2 pieces on row 3&4.)

To allow the glue to set properly, I left all the clamps at least half an hour in place. I spent the next 3 days of placing pieces, adding glue, placing clamps, doing something else or going to work in between and then coming back for the next round of gluing.

I made several rings, each consisting of 2 rows of wood. The process to make all of the rings was similar except for the diameter. So for each ring I first checked on my drawing what the diameter of the rings should be. Then I placed pieces of wood on my cardboard template in the right diameter. On top of that I glued a second row of pieces in the right diameter for that row.

In the bottom section of the egg the second row was larger, so I used some other pieces as support. Then I placed something heavy on top of the ring and let the glue set. The rings needed more than an hour for the glue to get strong enough.

When the ring felt strong, I glued it onto the 4 pieces of the previous row.

The next rows of the egg are mainly just repeating the last two steps. I continued to make rings and between the rings I placed 4 sets of 2 pieces glued together.

In this table you can see how many pieces I planned to use per row. Please remember that row 1&2 is the combined bottom row and row 33 is the top row.

In step 10 I checked how many pieces would fit in a full circle and I mentioned those numbers in the second row of the table. If I wanted each row to be filled, I would need 405 pieces, but I did not have that many pieces.

In the third row of the table, I planned to use only 4 pieces in all the rows that I marked in yellow. Then I would need 268 pieces, which is still a few pieces to many.

Since I only had 256 pieces, I decided to try to skip a few pieces in the other rings too. That worked very well and at the end of the build I even had a few pieces left over so I added them in the rows that originally only had 4 pieces. In the fourth row of the table I mentioned the pieces that I actually used in each row.

You might wonder how I could use 261 pieces, while I only had 256 pieces to start with. That is because some pieces were a bit too long to use, so I cut a few of my longest pieces in two halves, which gave me 5 additional pieces.

Here are some photos showing how I assembled more rows. The method is the same as for the previous rows.

Since the glue needs time to set and I only have a limited number of clamps, the assembly process needs to be done with a lot of time in between. The actual gluing only takes a few minutes, so in the evenings after work and early in the morning before going to work, I just glued another row.

I decided not to glue all rows, because then I would not be able to reach the inside of the egg later on to stain the wood.

Also the fact that the egg is in two parts, gives me the possibility to place something inside the egg later.

For the top side, I cut one large piece into 4 tiny pieces to help support the top row. I glued and assembled it and placed some weight on top to allow the glue to set. Then I had to check carefully that the top rows would fit on the egg, so I placed the 4 connecting pieces after I made the top rows and when I was confident that it would fit, I added the glue and clamps.

Since I had about 16 leftover pieces after I finished the top rows, I decided to fill some of the larger gaps in the bottom half of the egg with the remaining pieces. I added 4 sets of 2 pieces on row 3&4 and on some other rows I also added a few pieces until I had used all the pieces that I had. That made the egg look better.

In the table that I added to step 15 I have mentioned all the pieces that I used, so including the leftover pieces that I added here.

Finally all pieces are glued in place so now I have an egg. During the build I was a bit concerned that the egg would not look like an egg, but now that it is complete I am quite happy with how it looks.

As you can see it was again dark outside, so the window reflects the top side of the egg. On the cardboard at the left you can see the shadow of the egg.

With a bit of color the egg will look much better, so I decided to stain the wood. This was again quite time consuming, but I sat there listening to some music, so I enjoyed the process.

Staining the wood usually results in a rough surface as little wood fibers will stand upright. Therefore I used 180 grid emery paper and sanded the pieces a little bit, just enough to get a smooth surface but not that much that the color would disappear.

Some of the pieces really have a beautiful pattern. I did not expect that from a simple piece of construction wood.

Now the egg is ready and I can enjoy the result.