Eise Eisinga's Planetarium; Day of the Week Clock

In Franeker, a charming and historically rich town in the Netherlands, the brilliant Eise Eisinga created a remarkable planetarium right in his own living room! Despite the challenging task, he dedicated seven whole years to bringing his vision to life and in 1781, his dream became a reality. Today, this incredible planetarium still functions flawlessly and has earned the honor of being the oldest working planetarium in the world. It's no wonder that it's being considered for addition to the prestigious list of world heritage sites this summer! During my visit, I was so inspired by this incredible feat that I decided to take on the exciting project of rebuilding a portion of it myself. Now you can do that too. Specifically, we willl be working on the section of the ceiling that displays the year and points to the day of the week. With the help of a 3D laser cutter, you can bring this amazing piece of history to life in your living room!

Supplies

You're in for a treat! I've put together a fun YouTube video showcasing the 3D model I made of the incredible planetarium and the replica. The video starts with a playful animation zooming in on the clock for the day of the week and my charming little replica.

The replica is mostly made out of thin basswood. As the laser isn't very strong (only 1.6W), 1.5mm was about the max thickness it could reasonably cut. A small piece of oak is used as a base to stand the clock on. Blue, brown, white, gold and black acrylic paint is used to make the face plate. Some 0.1mm thick plastic (vinyl?) with adhesive backing helps in painting perfectly. Four screws measuring 4x25mm, along with some nuts, securely mount the mechanism and the backside of the clock. Wood glue is used for the rest of the clock. The clock mechanism I ripped from a Ravencourt Days of The Week Clock (currently unavailable, but an alternative could be DayClocks-Hexagon-Black-Clock-Office at amazon.com or this one from ebay.com. For tools (besides the laser cutter) you need a file, to the make a slanted edge for the part that shows the years, and some fine pliers. It's been such a fun and rewarding project, and I can't wait to see you make one and share it with the world!

Step 1: Housing

Get ready to put your laser cutter to good use! The housing for the clock is simple yet effective. All you need to do is use the image I've provided to cut out the parts. The large black square with four holes is the back plate, measuring 75x75mm, and you'll screw it on later. Make sure to scale the image on your laser cutter to match that. Once you have all the parts cut out, simply put them together with some wood glue. To ensure the right distance between the two parts, and prevent the nuts from rotating, glue the four tiny rectangular pieces on the inside corner. Not only do they provide the right distance between the two parts, they also prevent the nuts from rotating. While it's tempting to glue it to the back of the face plate of the clock, hold off on that for now. Paint it dark blue (blue with a few drops of black).

Step 2: Face Plate

Creating this clock is a fun and creative project! With the help of a laser cutter and some basic tools, you can make a beautiful and functional clock face that is sure to impress. The clock face has many intricate details that are too fine to paint by hand, but don't worry, a mask made of adhesive plastic will help you achieve the desired effect.

But first step is to make the plate itself. Mount a sheet of 1.5 mm basswood on your laser cutter's base plate. Mount it in such a way that it can stay there for some time without moving. Use the laser cutter to cut out the big rectanglular face plate. Its size should be 97mm x 142 mm. If you need to scale your image to achieve that, remember the scaling factor, so you can use it later. Remove only the cut out part, and leave the rest of the basswood mounted. It will be used to put the rectangle back in the same spot.

Next step is to completely paint the face plate blue (front and back). Let it dry.

While it dries you need to calibrate the laser cutter. Take a piece of the left-over wood from the first step, and cover it with the adhesive plastic. Now draw a small line using the laser cutter. Adjust its speed and power so, it just goes through the plastic, without burning into the wood (it might be just a bit visible, which is fine).

Next are the white, brown and dark blue circles. Cover the front with adhesive plastic and use the laser to barely cut out the circular patterns and the central hole. Remove the area (but keep the plastic) for the blue part and paint it dark blue (add a drop or two of black to the blue you used the background). Remove the area for the white part and paint it white (add a drop or two of brown to make it a bit off-white). Let it dry. Put the plastic parts back and remove the part for the brown area. Paint it brown. (if the plastic doesn't stick anymore, just cover remove all the plastic, cover it again and use the laser cutter to barely cut the circles again) let it dry.

Remove all the adhesive plastic and cover the face plate again. Barely cut the plastic with the days of the week and scale. In this step I slightly increased the laser power, to engrave the fine details, in case the paint didn't go into all the small areas. Use some fine pliers to remove all the parts that should become black and paint those black. Let it dry.

Once more remove all the adhesive plastic, and cover it again. Time to do the gold part in the same way as the black part.

After it is dry you can use the laser at normal power again to cut the central hole and the rectangle area for the years. The year hole needs a slanted edge, so use a file to make it so. When done, paint the edge of the hole gold.

Step 3: Year Disk

The years are painted on a disk that you need to reposition once a year. Securely mount some basswood on the base plate of the laser cutter. Cut the circle. Remove it, but leave the rest of the basswood in place. Paint the circle white (add a few drops of brown to make it off-white). Cover it with adhesive plastic, and barely cut the plastic with the digits of the years. Use pliers to remove the part that needs to be painted black, and paint the digits black. Let it dry, and do the same with the other side, but with the years starting with 2035.

Step 4: Pointer

Painting the pointer is a simple task. First, paint it with a very dark blue color. Then, paint the tip, end, and central part with gold. As for the small piece on the left, it can be taken from the clock mechanism, cut to size, and painted in gold. This piece will cover the axis of the clock and rotate around once every minute.

Step 5: Mounting It All Together.

The clock mechanism isn't fixed into place using screws, it just fits perfectly in the housing. Leave the rubber washer and nut in place, as seen in the picture. The little housing need four nuts mounted. I used some hotglue to keep them in place, they will be used to to mount the lid.

From the back, but the year disk first, then glue the box to the back plate, make sure the mechanism goes nicely centered. I added a 0.5 mm layer of foam in between the year disk and the mechanism, but I don't think it is really needed. After you put in the mechanism, close the back with the 4 bolts.

To create a stand, use a 60 x 60 x 15 mm oak piece with one slanted edge, and glue the clock face onto it. Congratulations! You have now successfully replicated the day of the week clock from the planetarium in Franeker.